Browsing by Author "Sreekala, G S"
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ThesisItem Open Access Biomass production and partitioning of photosynthates in ginger (Zingiber Officinale R.) under different shade levels(Department of Horticulture, College of Agriculture, Vellayani, 1999) Sreekala, G S; KAU; Jayachandran, B KA pot culture experiment was conducted at the College of Agriculture, Vellayani during the year 1997 - 1998 to study the effect of shade on biomass production and partitioning of photosynthates in ginger cv. Rio-de-Janeiro. The experiment was laid out in completely randomised design with five shade levels (open, 20, 40, 60 and 80 per cent) and four replications. Artificial shade was provided using high density polyethylene shade nets and calibrated using quantum photo sensors. Two months after planting, ginger plants were labelled using 14C . After tagging, one set of samples were collected immediately. Subsequently, harvesting of the tagged plants were done once in sixty days after labelling. Monthly observations of various growth parameters were taken from two months after planting. At six months after planting photosynthetic related parameters were measured using leaf chamber analyser. The various growth parameters like number of tillers, leaf area, leaf dry weight, dry matter production, crop growth rate, relative growth rate, net assimilation rate at final stage, leaf area index which contributed to yield was highest under 20 per cent shade. This shows that the plant prefers low shade intensity compared to open. The yield recorded under 20 per cent shade was significantly superior compared to open. But the yield at open and 40 per cent shade were on par. Higher shade levels decreased the yield. This shows that the crop can tolerate shade up to 40 per cent. Different shade levels influenced the quality of ginger rhizomes. While volatile oil was maximum under heavier shade levels in general ( 60 and 80 per cent ), non- volatile ether extract was higher under 20 per cent shade. Starch as well as crude fibre content was more in plants grown under open condition. The photosynthetic rate and related parameters of ginger were measured at six months after planting using leaf chamber analyser. Photosynthetically active radiation on leaf surface as well as stomatal conductance was high under open condition. But leaf internal carbon dioxide concentration as well as stomatal resistance was high under heavier shade levels (60 and 80 per cent). Photosynthetic rate as well as the transpiration rate was maximum in plants grown in open. Though, at 20 per cent shade, the photosynthetic rate was less, the yield was high. This might be because of the photo oxidation that has taken place at high light intensities or due to the inefficient translocation of the photosynthates in open condition compared to 20 per cent shade. Radio tracer analysis done using labelled 14C has shown that under open condition, though initial intake of carbon dioxide was more, most of the carbon dioxide taken are seen in the above portion itself. While in 20 per cent shade most of the carbon dioxide taken in has translocated to the lower portion. This shows that under low light intensity the photosynthates produced has translocated efficiently to the lower portion while in open condition efficient translocation has not taken place. The results indicate that 20 per cent shade level is favourable for growing ginger plants to get higher rhizome yield. The yield at 40 per cent was on par with that of open. This shows that crop can tolerate shade upto 40 per cent. Thus the partially shaded coconut gardens can be exploited for increasing the area under ginger which may help in doubling the production.ThesisItem Open Access Characterisation of boron deficient coconut palms (Cocos nucifera L.)(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2017) Athulya, S Nair; KAU; Sreekala, G SThe experiment entitled ‘‘Characterisation of boron deficient coconut palms ( Cocos nucifera L.)” was undertaken at farmer’s field in Kalliyoor panchayat of Thiruvananthapuram district during the period from April 2015 to March 2016. The objective of the study was to identify boron deficient coconut palms and predisposing factors responsible for deficiency based on the visual diagnosis and to study the morphological characters of boron deficient and healthy coconut palms. The survey was conducted among hundred coconut palms in Kalliyoor panchayat of Thiruvananthapuram district to identify coconut palms deficient in boron based on visual symptoms listed by CPCRI. Based on the symptoms a ten scale score was developed and boron deficient palms were categorized as mild, moderate and severe intensity and compared with soil and plant boron status . The field, soil , plant characteristics and management aspects of coconut palms deficient in boron were identified based on questionnaire prepared. The morphological and yield parameters were observed at 45 days interval for one year in five palms each from mild, moderate and severe intensity and was compared with healthy palms. The results of the survey showed that the boron deficiency in palms were restricted to age group between 20-45 years grown on red loam soil with pH 6.0-7.5. The deficiency symptoms were common in coconut fields where intercropping was practiced (63 %) and in other fields with poor agronomic management (37 %). Mite and coreid bug attack were prominent ( 89 % and 53 % respectively). Diseases among deficient palms were restricted to 26 percentage and leaf rot was the major one. Common visual symptoms of palms with mild intensity were reduced leaf size, length. hooked leaves, fused leaves, and leaflets with relatively higher internodal Necrotic inflorescence, reduced nut set, poor nut size, nuts with hen and chicken symptoms and crowded crown were prominent in moderate to severely intensity groups. The morphological and yield parameters of selected palms of four groups indicated significant difference between palms of healthy and severe intensity for number of leaves, leaflet internodal length, number of female flowers per bunch of unfertilized inflorescence, opened and unopened spadices, bunches per palm, malformed nuts, volume of nut water, weight of embryo and shell throughout the observation period . The cortical cells of root were loosely packed for boron deficient palms of moderate and severe intensity. Nuts from healthy palms when compared with that from the mild, moderate and severe intensity differed significantly with respect to weight of unhusked nut, weight of husked nut, nuts set per bunch, nuts per palm per year, polar and equatorial diameter of unhusked nut, thickness of husk , weight of opened nut, thickness of meat, weight of kernel ,weight of copra and oil content and the difference was proportional to enhancement in intensity of deficiency. The available boron status in soil and plant were significantly superior in healthy palms. Identification of predisposing factors revealed poor agronomic management, intensive cultivation and low organic matter resulted in B deficieny in Coconut growing areas. The results indicated that B had marked influence in enhancing the yield characteristics of coconut particularly of thickness of meat, weight of kernel, weight of copra, oil content etc. There is a significant reduction in the yield of deficient coconut compared to that of healthy palms. The study thus substantiate the importance of boron in the nutrition of coconut palms.ThesisItem Open Access Characterisation of coconut palms (Cocos Nucifera L.) showing general yellowing(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2017) Aparna, K; KAU; Sreekala, G SThe study on “Characterisation of coconut palms (Cocos nucifera L.) showing general yellowing” was undertaken in selected coconut palms coming under Thiruvallam of Thiruvananthapuram district from March 2016 to March 2017. The objective was to evaluate the field characteristics and nutritional status of soil and coconut palms showing general yellowing and to formulate a management strategy. Coconut palms of variety WCT showing general yellowing which advance from lower to upper whorls of leaves were identified from farmer’s field of Thiruvallam. Fifteen palms showing uniform pattern of general yellowing and five healthy palms were selected from five farmer’s fields. Field, soil, plant and management practices followed by farmers were studied in the selected palms to identify the pre disposing factors leading to general yellowing. Observations on morphological and yield characteristics of selected coconut palms were recorded for one year at 60 days interval. Soil and plant samples were collected and analysed for macro and micronutrients. Based on soil test results the quantity of deficient macro nutrients were calculated and applied as per package of practices recommendation of Kerala Agricultural University. The soil and plant sample was again analysed six months after the application of fertilisers. Data generated on field characterization revealed the type of soils as red loam soils with good drainage in all the selected coconut palms. High soil organic matter was seen in all the healthy coconut palms while eighty percentage of coconut palms showing general yellowing were under medium status of organic matter. Of the coconut palms showing general yellowing, fifty three percent belonged to the age group of 31-35.The disease and pest incidence in the healthy palms was only twenty percent while it was more than fifty percent in palms showing general yellowing. The morphological, physiological and yield parameters of selected palms indicated significant variation in number of leaves showing yellowing, chlorophyll content, membrane integrity, relative water content, number of bunches, number of female flowers per bunch of inflorescence, number of nuts set per bunch, weight of nut, weight of copra and oil content in coconut palms showing general yellowing compared to healthy palms. However after the application of nutrients significant increase in chlorophyll a content, total chlorophyll content, membrane integrity and relative water content was noticed in coconut palms showing general yellowing. The soil and leaf nutrient analysis revealed a significant variation in N, P, K, Ca, Mg, S and B content between coconut palms showing general yellowing and healthy palms. However, observations made at six months after the application of manures and fertilisers revealed a significant increase in soil pH, organic carbon, N, P, K, Ca, Mg, B and Cl in the soil and N,P,K of index leaf of coconut palms showing general yellowing. There was no significant variation in the S, Fe, Mn, Zn and Cu before and after the application of manures and fertilisers. The present study based on nutritional status and visual symptoms revealed that low soil nutrient status of N, P, K, Ca and Mg have resulted in the general yellowing in coconut. The application of fertilisers as per average management recommended by KAU (2016) could only enhance the soil N, P, K and Mg status to medium level while for calcium it still remained in low status. Thus a higher dose of N, P, K, Ca and Mg are required for the palms showing general yellowing to substantially improve the nutritional status of the palm.ThesisItem Open Access Characterization and quality analysis of black pepper (Piper nigrum L.) genotypes of Kerala(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2021) Reshma, P; KAU; Sreekala, G SThe present study entitled “Characterization and quality analysis of black pepper (Piper nigrum L.) genotypes of Kerala” was taken up with the objectives of survey, characterization and quality analysis of black pepper genotypes of Kerala based on morphological and biochemical parameters. The survey conducted in black pepper plantations and homesteads in fourteen locations of six Agro-Ecological Units (AEUs) identified twenty one genotypes. Five genotypes designated as G1 (Wayanadan), G2 (Chumala), G3 (Vellayaranmunda), G4 (Nadan), G5 (Nadeshan) from AEU 21 (Wayanad Eastern Plateau), six genotypes designated as G6 (Karimunda), G7 (Neelamundi), G8 (Cheppukulamundi), G9 (Vattamundi), G10 (Thulamundi), G11 (Manjamunda) from AEU 12 (Southern and Central Foothills), three genotypes designated as G12 (Chengannurkodi), G13 (Vellanamban), G14 (Jeerakamunda) from AEU 14 (Southern High Hills), three genotypes designated as G15 (Kuthiravally), G16 (Kottanadan), G17 (Arimulak) from AEU 3 (Onattukara Sandy Plains), two genotypes designated as G18 (Padappan), G19 (Karivilanchy) from AEU 8 (Southern Laterites) and two genotypes designated as G20 (Narayakodi) and G21 (Panniyur 1) from AEU 4 (Kuttanad) were selected for the study. Twenty one genotypes were morphologically characterized for both qualitative and quantitative characters. Thirty four qualitative characters were observed and among those only twenty two characters showed variability. Characters such as runner shoot production, pubescence on stem, type of veining, leaf texture, spike colour, spike orientation, spike shape, spike fragrance, spike proliferation, colour change while fruit ripening, fruit taste and seed texture were uniform in all the selected genotypes. The UPGMA dendrogram divided all the genotypes into 15 clusters at 73 per cent similarity. Sensory evaluation of the selected black pepper genotypes showed a significant variation for colour, odour, taste and flavour. G16 (Kottanadan) was significantly superior in taste while G15 (Kuthiravally) was superior in odour and flavour. Thirty four quantitative characters were recorded for plant, leaf, inflorescence, fruit and seed characters. Summarizing these quantitative characters using descriptive statistics revealed wide range of variability in number of well developed fruits per spike, number of spikes per 30 cm2 , number of spikes per vine, bulk density and specific leaf area. Principal component analysis was undertaken to examine the variation and to estimate the relative contribution of various trait for total variability. The principal component analysis for twenty three yield related characters revealed seven principal components at 85.53 per cent variability. The eleven quantitative characters such as juvenile leaf length, leaf length, leaf width, number of spikes/30 cm2 , number of spikes per lateral branch, number of spikes per vine, number of nodes per lateral branch, number of well developed berries per spike, berry diameter, support height and vine column diameter contributed more to the yield. The score plot identified fifteen clusters in which genotypes with superior yield namely, G1 (Wayanadan), G4 (Nadeshan), G5 (Nadan), G15 (Kuthiravally) and G21 (Panniyur 1) formed unique clusters. Minimal data set generated for black pepper included four characters namely, number of nodes per lateral, number of well developed berries/spike, number of spikes/30 cm2 and berry diameter. The principal component analysis for five physiological parameters revealed one principal component at 73.34 per cent variability. Genotypes with high leaf thickness, high relative water content, high epicuticular wax, low specific leaf area and low stomatal density were associated with drought tolerance in black pepper. Sixteen clusters were identified based on score plot. Biplot analysis identified genotypes G16 (Kottanadan), G13 (Vellanamban), G6 (Karimunda), G7 (Neelamundi), G18 (Padappan) and G20 (Narayakodi) as most desirable genotypes for drought tolerance. The principal component analysis for six quality attributes revealed two principal components at 66.62 per cent variability. The genotypes were grouped into seventeen clusters based on score plot while the biplot identified genotypes G16 (Kottandan), G15 (Kuthiravally), G21 (Panniyur 1), G19 (Karivilancy), G17 (Arimulak), G13 (Vellanamban) and G6 (Karimunda) as the high quality ones. The genotypes studied for qualitative, quantitative, physiological and quality traits showed a moderate variability and can be used in the selection of suitable parents for breeding purpose and gene mapping studies.ThesisItem Open Access Cost effective technology for home scale and small scale production of virgin coconut oil(College of Agriculture, Vellayani, 2015) Thanuja, T T; KAU; Sreekala, G SThe investigation on “Cost effective technology for home scale and small scale production of virgin coconut oil” was carried out during the period 2013- 2015 at the Department of Plantation Crops and Spices, College of Agriculture, Vellayani, Kerala to standardise the cost effective technique for home scale and small scale production of virgin coconut oil through fermentation, induced fermentation and centrifugation and to compare the technology developed with the traditional boiling method. The study was conducted in four experiments and the coconuts for the experimental purpose were collected from the variety WCT (West Cost Tall). Standardisation of fermentation method was done by extracting coconut milk with coconut water (CM+CW 1:1) and with water in the ratio 1:1 (CM+W 1:1) and 1:2 (CM+W 1:2) and kept for 24, 36 and 48 hours for fermentation. The oil recovered was subjected to drying at 40, 45 and 50°C and the sensory parameters and percentage oil recovery were significantly superior at 50°C. The fermentation method was replicated during June- July, Nov- Dec and March- April. The atmospheric conditions was not congenial for the VCO production during Nov- Dec. The oil recovery was nil below an atmospheric temperature of 31.05°C. The maximum relative humidity when the oil was separated ranged from 90.50 per cent to 97 per cent. The minimum relative humidity during that period ranged from 67 per cent to 83 per cent. For the standardisation of induced fermentation method, isolation of microorganisms from fermented coconut milk at 24 and 36 h was done and the best isolate identified belonged to the genus Lactobacillus. Induced fermentation with one per cent of Lactobacillus broth showed significantly higher oil recovery compared to natural fermentation. Standardisation of virgin coconut oil production by centrifugation was also carried out by extracting coconut milk after 10 hours of chilling at different revolutions per minute (rpm) and time. The coconut milk extracted with coconut water at 12000 rpm for 15 minutes and dried at 50°C recorded significantly higher oil recovery (28.087 per cent). The virgin coconut oil produced by fermentation, induced fermentation and centrifugation were compared with traditional boiling method. A higher oil recovery and B:C ratio with minimum refractive index was observed under centrifugation while moisture content, specific gravity, relative density, acid value, peroxide value, iodine value, polenske value and saponification value did not vary significantly between different methods of extraction. The yellowing index and sensory parameters like odour and taste were significantly superior for traditional method while unsaponifiable matter, total phenolic content, free radical scavenging activity, total antioxidant capacity and the reducing power were significantly superior for fermentation method. The shelf life of the VCO produced by different methods was less than 3 months. The fermentation, present study implies that virgin coconut oil produced by induced fermentation and centrifugation had better quality parameters, antioxidant properties and cost effectiveness compared to traditional boiling method. Fermentation method can be adopted for home scale production while centrifugation and induced fermentation can be suggested as a better method for small scale production of virgin coconut oil.ThesisItem Open Access Effect of pre treatments and curing methods on the quality characters of processed cardamom (Elettaria cardamom (L) Maton(Department of processing technology, College of horticulture, Vellayani, 2012) Sonia, V; KAU; Sreekala, G SThe research on “Effect of pre treatments and curing methods on the quality characters of processed cardamom (Elettaria cardmomum (L.)Maton” was undertaken at Department of Processing Technology, College of Agriculture, Vellayani with the objective of developing a pre treatment for cardamom which can retain good quality green colour having better flavour, texture, appearance and acceptability. The experiment was done at Cardamom Research Station Pampadumpara and the analysis was carried out at Department of Processing Technology, College of Agriculture, Vellayani. The experiment was laid out in factorial completely randomised design with three replications. The cardamom capsules were treated with different chemicals and dried under two curing methods. Pre treatments consisted of 1% of sodium carbonate, potassium carbonate, sodium hydroxide, sodium bicarbonate, magnesium sulphate, copper acetate and 0.1% of ascorbic acid, citric acid, polyethylene glycol and 500 ppm of naphthalene acetic acid. An untreated control was also included in the experiment. These cardamom capsules were then dried under conventional and modern drier and evaluated for physical, chemical and sensory qualities. The effect of pre treatments and curing methods on physical qualities of cardamom was evaluated. The boldness, bulk density and instrumental measurement of texture were not affected by the pre treatments as well as by curing methods. The greenness and total colour difference were influenced by the pre treatments. The cardamom capsules treated with 1% sodium hydroxide and sodium carbonate were superior in imparting greenness to the capsule colour. The result of total colour difference also substantiates this. The chemical parameters such as moisture, chlorophyll and essential oil content were significantly influenced by different pre treatments. The curing methods did not influence the chlorophyll and essential oil content of cardamom capsules. Flavour profiles of essential oil content of small cardamom were analysed using Gas Chromatography Mass Spectrometry. The major ten chemical components (1,8-cineole, α -terpinyl acetate, limonene, linalool, sabinene, trans nerolidol, α-terpineol, linalyl acetate, myrcene, α- pinene) present in essential oil of small cardamom were statistically analyzed. Cardamom capsules treated with 1% sodium hydroxide and 1% sodium carbonate showed better flavour profile with respect to α-terpinyl acetate, linalool and linalyl acetate in essential oil of small cardamom compared to other chemical pre treatments. The moderate content of 1,8-cineole with higher α -terpinyl acetate, linalool and linalyl acetate might have resulted in better flavour as noticed by sensory evaluation of cardamom capsules pre treated with 1% sodium hydroxide and 1% sodium carbonate. Conventionally cured cardamom capsules showed better retention of flavour compared to modern curing method with respect to 1,8-cineole, α - terpinyl acetate, limonene, linalool, α-terpineol and linalyl acetate. The pre treated cardamom capsules were analysed to find the residue content of the pre treated chemicals. The residue of sodium, potassium, magnesium, ascorbic acid and citric acid analysed were below the toxic level and would not cause any harm since they are needed in trace amounts in human body. The presence of heavy metal copper was also below the maximum residual level. The naphthalene acetic acid (NAA) content was a bit slightly above the normal level recommended for apple, pear, quince and pineapple. A significant level of residue of polyethylene glycol (PEG) was noted compared to control. The sensory tests carried out revealed better colour, flavour, texture, appearance and overall acceptability for the cardamom capsules treated with 1% of sodium carbonate and sodium hydroxide compared to other pre treated capsules as well as control. The flavour, texture and overall acceptability was superior in cardamom capsules dried under conventional curing compared to modern curing. The study concludes that the pre treating cardamom capsules with 1% sodium carbonate or 1% sodium hydroxide for two minutes gave better colour, flavour and overall good acceptability of cardamom. Both curing methods were ideal with regard to the general colour and texture as indicated by instrumental measurements. However the flavour profile of essential oil of small cardamom and sensory qualities were scored in favour of conventional curing method.ThesisItem Open Access Evaluation of elite clove (Syzigium aromaticum (L.) Merr. and Perry) accessions and standardization of pollination techniques(Department of Plantation Crops and Spices, College of Agriculture , Vellayani, 2020) Reddappa, J B; KAU; Sreekala, G SThe present study entitled “Evaluation of elite clove (Syzigium aromaticum (L) Merr. & Perry) accessions and standardization of pollination techniques” was taken up with the specific objective to evaluate elite clove accessions and to standardize pollination techniques for hybridization. The twelve elite accessions identified from estates of Trivandrum and Kollam districts of Kerala designated as BRC-1, BRC-2, BRC-3, BRC-4, MRC-5, MRC-6, MRC-7, MRC-8, AMC-10, AMC-11, AMC-12 and AMC-13 were evaluated during the period of 2018-2020. Quantitative characterization was done with 25 quantitative characters including tree, leaf, bud, flower, yield, fruit and seed characters. The girth of the tree at 30 cm height was maximum in BRC-3 (165 cm). Highest number of inflorescence/m2 was recorded in AMC-12 (156.25). The number of flower buds/inflorescence was maximum in MRC-6 (17.25) while single bud fresh and dry weight was highest in BRC-3 with 398.72 mg and 127.26 mg respectively. The mature bud length among the clove accessions was the maximum in BRC-1 (19.34 mm) whereas the mature bud diameter was maximum in BRC-3 (6.45 mm). The dry bud yield per tree was the highest in MRC-7 (8.13 kg) followed by BRC-1 (7.48 kg). Quantitative characters summarized based on the descriptive statistics revealed wider range of variability in single bud weight fresh, number of inflorescence/m2, single bud weight dry and girth of the tree. Multi Dimensional Scaling (MDS), a multivariate analysis done on 25 variables with 12 observations revealed 10 dimensions and the contribution of MDS Dimension-1 and Dimension-2 were 75.76 and 17.21 percent with cumulative variance of 92.97 percent respectively. Based on the scree plot of MDS, first 2 dimensions were selected for generating the biplot. Based on MDS configuration eight clusters of selected clove accessions were identified. Dendrogram representing the relationship among 12 elite accessions based on Euclidean distance also identified same eight clusters of clove accessions that identified in MDS configuration. The linkage analysed based on the biplot of two dimensions of multidimensional scaling of biplot coordinates revealed a strong positive association between most of the characters measured except, girth at 30 cm height, number of inflorescence per m2, single bud weight fresh and single bud weight dry. Minimum Data Set for identifying a promising clove accession generated revealed accessions BRC-1, MRC-5 and MRC-6 had better ideotype and can be suggested as elite or superior accessions. The experiment on floral phenology and biology was carried out in clove plants at Braemore estate, Trivandrum district. The flower opening time of the clove flowers observed were between 2:30-6:30 pm. However the percentage of flower opened was maximum between 3.30- 5.30 pm. The number of stamens per flower varied from 167 to 343. The rupturing of anthers started 36 hours before anthesis and maximum anther dehiscence occurred between 36 h before anthesis till anthesis. The pollen grains were monad, radially symmetrical, triangular, trizonosyncolporate and were having exine ornamentation. The polar diameter of pollen grain ranged from 17.06-18.22 µm and the equatorial diameter of pollen grain ranged from 19.40-20.70 µm. The stigma receptivity by hydrogen peroxide test revealed stigma receptivity was there upto six days from anthesis and maximum stigma receptivity was observed on fifth day of anthesis with highest number of bubbles (31.40 per cent). The emasculation should start from 48 hour before flower bud opens which was revealed by the starting of separation of the petals since anthers started rupturing from 36 hour before anthesis. Pollen viability by iodine potassium iodide method revealed that pollen viability was maximum at 12 hour before anthesis (94.02 per cent). Pollen fertility was also maximum on the pollen collected 12 hour before anthesis (82.83 per cent). Thus the pollen collection should be undertaken 12 hour before anthesis. Pollen collected and dried at 50°C and stored upto two months of storage in refrigerator had maximum pollen viability whereas pollen fertility was maximum in pollen dried at 50°C and stored in desiccator. The hybridization was carried out on selected five clove plants as male and female parents. The percentage of fruit set ranged from 15 per cent to 42.5 per cent and average fruit set from all the plant combinations was 28.87 per cent. The study on “Evaluation of elite clove (Syzigium aromaticum (L) Merr. & Perry) accessions and standardization of pollination techniques” revealed that clove accessions such as BRC-1, MRC-5 and MRC-6 had superior ideotype and superior in effective yield. The floral phenology of clove was studied and pollen collection, storage and artificial hand pollination in clove was standardized.ThesisItem Open Access Nutrient scheduling in bush pepper (piper nigrum L.)(Department of Plantation Crops and Spices College of Agriculture, Vellayani, 2018) Farhana, C; KAU; Sreekala, G SThe present study entitiled “Nutrient scheduling in bush pepper (Piper nigrum L.) was taken up with the specific objective to standardize potting media and nutrient level in bush pepper for yield. The pot culture experiment on bush pepper was carried in the Department of Plantation Crops and Spices, College of Agriculture, Vellayani during the period 2017-18 using variety Panniyur 1.The efficacy of different combinations of organic manures and different levels and intervals of inorganic fertilizers were evaluated. The experiment was laid out in completely randomized design with three different types of potting media (P1, P2, P3), five inorganic fertilizer treatments (I1, I2, I3, I4, I5) and a control. The different types of potting media used were soil + FYM + neem cake + coir pith compost (P1), soil + FYM + vermicompost + coir pith compost ( P2) and soil + FYM + leaf compost + coir pith compost (P3) in the ratio 3:3:1:1. Inorganic fertilizers applied at different levels and intervals were I1- 37.5: 37.5: 50.0 g of NPK plant-1 year-1at monthly splits, I2 - 37.5: 37.5: 50.0 g of NPK plant-1 year-1 at quarterly splits, I3 - 25.0: 25.0: 50.0 g of NPK plant-1 year-1 at monthly splits, I4 - 25.0: 25.0: 50.0 g of NPK plant-1 year-1 at quarterly splits and I5 - 12.5:12.5:25.0 g of NPK plant-1 year-1 as soil application at equal monthly splits up to 3 MAP and foliar application of 13:0:45 (0.5 %) at fortnightly intervals from 4th MAP. The control treatment contained soil + sand+ FYM, (1:1:1) as potting mixture and inorganic fertilizer applied as per package of practices recommendations of KAU (1.0, 0.5, 2 g NPK plant-1 at bimonthly interval). Trichoderma @ 1 g kg-1 of potting medium and lime @ 50 g plant-1 were applied to all the treatments. The results of the study revealed that potting media containing soil + FYM + vermicompost + coir pith compost (3:3:1:1) and inorganic fertilizers applied at the rate of 25.0: 25.0: 50.0 g of NPK plant-1 year-1at quarterly splits (p2i4) recorded significantly higher plant growth characters like number of secondary branches, length of primary branches, length of secondary branches, number of leaves and leaf area from 8MAP to 12 MAP. Fresh weight, dry weight and volume of roots at 12 MAP were also significantly higher for the treatment combination, p2i4 Significantly higher dry matter production (150.92 g plant-1) at 12 MAP and chlorophyll content at 6 MAP was noticed in p2i4 while dry matter production was the least in control (72.42 g plant-1). The yield attributes like number of spikes plant-1, length of spike, number of berries spike-1, hundred berry weight, hundred berry volume, fresh and dry weight of berries were significantly higher for p2i4 recording a dry yield increase of 98 per cent over the control. Quality parameters of berries revealed that essential oil, oleoresin and piperine were highest in p2i4 while highest starch content was obtained in p1i5. . The total uptake of nitrogen, phosphorus and potassium by bush pepper was significantly superior with a higher uptake of N (2.159 g plant-1), P (155.17 mg plant- 1 ), K (2.367 g plant-1), Ca (1.577 g plant-1), Mg (296.64 mg plant-1) and S (253.34 mg plant-1) in p2i4. Higher nitrogen harvest index (33.58 %), phosphorous harvest index (41.03 %) and potassium harvest index (31.41 %) were recorded from p2i4, indicating that nutrient removal in bush pepper was proportional to the yield. The discounted benefit-cost ratio was 2.51 with 67 % of Internal Rate of Return (IRR) for p2i4 implied that investments made in bush pepper following the above treatment was highly profitable. The results of the study indicated that growing bush pepper in potting medium containing soil + FYM + vermicompost + coir pith compost ( 3:3:1:1) with the application of inorganic fertilizers @ 25.0: 25.0: 50.0 g of NPK plant-1 year-1 scheduled at quarterly intervals produced better growth characters like number of secondary branches, length of primary and secondary branches, number of leaves, total leaf area , root dry weight and yield parameters like number of spikes and number of berries spike-1 which ultimately doubled the yield compared to the package of practices recommendations of KAU.ThesisItem Open Access Pollination biology of black pepper (Piper nigrum L.)(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2019) Pooja, S; KAU; Sreekala, G SThe present study entitled “Pollination biology of black pepper ( Piper nigrum L.) was carried out at College of Agriculture, Vellayani with specific objectives to study the floral morphology, floral phenology, mode of pollination and breeding system in black pepper. The experiments on floral morphology and floral phenology were carried out in twenty five field grown black pepper plants of variety Panniyur 1. The experiments on the role of wind, insect, rain water and dew on pollination and different types of breeding system were carried out in both field and fifty bush pepper plants of Panniyur 1 maintained in pots. The plants were observed from March 2018 to March 2019 for studying the floral morphology, floral phenology, agents of pollination and breeding system. The floral morphology revealed light green (149 B ) colour in 52 % and dark green colour (140 A) in 48 % of the observed flowers as per the Royal Horticulture Society Colour Charts. The odour of the flower was slightly minty during the first five minutes and then increased to strong minty after 30 minutes and became light minty six hours after keeping in closed containers. Presence of nectar was noticed on the black pepper flowers. Anthesis started from 4-5 pm and was maximum between 6-7 pm and extended upto 12 midnight. The flower size was maximum (1.53 x 1.34 mm) on fifth day of stigma receptivity. The number of flowers in a spike varied from 48 to 98 flowers depending on the length of spike. The number of anthers in each flower was four and anther dehiscence was longitudinal. The anther dehiscence occurred from 11 am and continued till 4 pm and was maximum at 2-3 pm. The number of pollen grains was counted using haemocytometer and it varied from 5,00,000 – 7,00,000 pollen grains per inflorescence. The pollen morphology studied using Scanning Electron Microscope (SEM) revealed monosulcate pollen grains with mean polar diameter of 10.414 µm and mean equatorial diameter of 7.803 µm having an exine thickness of 924.8 nm. The stigma was 4 lobed, wet type and papillate. The duration of stigma receptivity was for 7 days with peak stigma receptivity was on fifth day of anthesis. Pollen was available in an inflorescence from 9 to 12 days from the first day of anthesis depending on length of spike and was available throughout the year in a plant. The longevity of flowers varied from 14 to15 days. Pollen fertility studies by Acetocarmine test revealed that 91% of the pollen were fertile. The pollen viability by 2,3,5-triphenyl tetrazolium chloride (TTC) stain and iodine potassium iodide (IKI) stain was 91.03% and 92.4% respectively. In vitro germination in Brewbakers medium showed highest pollen germination at 5% sucrose. In vivo germination was done through diaminobenzidine (DAB) test and aniline blue fluorescence method for 6 h and 24 h respectively and imaged through fluorescent microscopy. The cross and longitudinal section of the immature spikes revealed the emergence of ovary and stamens. Flower emergence duration ranged from 19 to 20 days. Flowering frequency in black pepper was maximum in the month of July and the flowering intensity was maximum in the fifth day of anthesis. The anthesis period in an inflorescence varied from 9 to 12 days depending on length of spike and was noticed throughout the year in a plant. Duration of spiking was 26.84 days while spiking extended for 259.5 days in a plant population. The fruit is a drupe and the mean period taken from fertilization to maturity was 150-175 days. The percentage of fruit set with rain water in field grown pepper was 92.76% and that for pot grown bush pepper was 92.90%. The percentage of fruit set by experiments on wind pollination resulted in 77.67% with wind alone and 92% with wind and geitonogamy in field grown black pepper plants and 59.39% with simulated wind and 96% with wind and geitonogamy in pot grown bush pepper plants. The floral biology of the black pepper revealed numerous pollen with very small grain size and pendulous spike supporting the characteristics of wind pollinated plant. Presence of dew was observed from June to December and the dew collected from the inflorescence showed the presence of pollen grains which suggests the role of dew also in the pollination of pepper. Three different floral visitors of the black pepper spike were and black ant, yellow crazy and pollu beetle visting day and night. However the role of insects in pollination could not be confirmed, but collection of nectar was noticed by black ant and yellow crazy ant while visiting the flowers. Studies on breeding system revealed high fruit set in geitonogamy followed by autogamy, open pollination and xenogamy. However no fruit set was noticed due to apomixis. The study on pollination biology of black pepper revealed the floral biology, phenology and the role of rain followed by wind and dew in pollination and supported geitonogamy, autogamy, open pollination and xenogamy.ThesisItem Open Access Postharvest management practices in papaya (carica papaya L) for improving shelf life(Department of Processing Technology, College of Agriculture,Vellayani, 2014) Jayasheela, D S; KAU; Sreekala, G SThe present investigation entitled “postharvest management practices in papaya (carica papaya L) for improving shelf life” was conducted at department of processing technology, College of Agriculture, Vellayani to determine the stage of harvest maturity of papaya for local and distant market and to standardize postharvest practices for improved shelf life with minimum nutritional loss. The study was carried out in three different continuous experiments. For local market, papaya fruits harvested at ¼ yellow (144.37 DFFB – Days From Full Bloom) and ½ yellow (146.12 DFFB) stages revealed ¼ maturity as the best stage of harvest due to increased shelf life. For distant market, the fruits were harvested at one stripe yellow (142.00 DFFB) and fully mature green (139.38 DFFB) and fruits harvested at fully mature green stage had more shelf life and hence selected as best stage of harvest for distant market. Investigation on the efficacy of different sanitizing agents on surface decontamination revealed that papaya fruits harvested at ¼ yellow for local market and fully mature green fruits for distant market, washed and treated with hot water at 50% C for 20 minutes and warm sodium hypochloride at 150 ppm was effective in reducing bacterial and fungal population. The effect of waxing and ethylene absorbent was studied on papaya fruits harvested for local and distant markets, sanitized with the two best sanitising agents. For local market, fruits harvested at ¼ maturity and sanitised with hot water at 500 C for 20 minutes followed by cooling, waxing and packing with ethylene absorbent (KMnO4 – Potassium permanganate) 8.0/kg fruit as sachet in corrugated fibre board boxes recorded highest shelf life (11.00 days), lowest physiological loss in weight (1.84 per cent ), lowest loss in membrane integrity (58.18 percent leakage), lowest respiration rate (30.33 mg CO2 /kg/hr), highest total soluble solids (12.660 Brix), least microbial population and less mechanical damage. For distant market, fruits harvested at fully mature green stage sanitised with hot water at 500C for 20 minutes followed by cooling , waxing and packed in corrugated fibre board boxes with ethylene absorbent in sachet (KMnO4 8.0g/kg fruit) improved the shelf life (12.33 days) of fruits and showed lowest physiological loss in weight (2.08 per cent), lowest loss in membrane integrity (57.82 percent leakage), lowest respiration rate (35.00 mgCO2/kg/hr) higher total soluble solids (11.330 Brix), microbial population and less mechanical damage. Further studies are required for the refinement of the technology for reducing postharvest losses in papaya fruits for transport to distant market.ThesisItem Open Access Protocol development for gel stabilization and nutraceuticals in aloe vera (L.) Burm. f.(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2021) Maheswari R S Nair; KAU; Sreekala, G SThe investigation entitled “Protocol development for gel stabilization and nutraceuticals in Aloe vera (L.) Burm. f.” was carried out in the Department of Plantation Crops and Spices, College of Agriculture, Vellayani during March 2016 to December 2019. The project envisaged formulation of a low cost stabilization technique for aloe gel using herbal extracts and aromatic oils and development of protocols for the preparation of dried latex and marketable nutraceuticals using aloe gel. The study was carried out as four experiments. The first experiment was to study the keeping quality and natural spoilage flora of fresh gel while the second experiment was for the standardization of curacao aloe (dried latex). The third experiment was on gel stabilization using herbal extracts and essential oils. Preparation of nutraceuticals from the stabilized liquidized aloe gel juice was the final experiment. The keeping quality and natural spoilage flora of fresh gel were assessed by subjecting the liquidized aloe gel juice to storage in glass bottles under ambient condition for seven days. The liqudized aloe gel juice was off white in colour for first three days of extraction with mild vegetative odour and got sedimented with foul smell from fourth day onwards. The liquidized aloe juice could not be stored for more than a day due to increased microbial population from the second day of storage. Preliminary trails conducted by pasteurizing the liquidized aloe gel juice at 65 0C and 15 psi pressure for 13 minutes followed by flash cooling registered no microbial population even after seven days of storage. The latex collected from aloe leaves was subjected to different methods of drying such as boiling followed by cooling, sun drying, shade drying and oven drying. Appearance, colour and aloin content (271.62 mg/ml) of dried latex was significantly higher for shade drying. Liquidized aloe gel juice was pasteurized and added with varying concentrations of three forms (aqueous, tincture, decoction) of herbal extracts and essential oils after adjusting the pH to 3.5 by adding 0.5 per cent of citric acid for gel stabilization. The treated samples were kept for a month and based on microbial population and minimum inhibitory concentration best treatment of each form was selected from preliminary trials for aloe gel stabilization. Gymnema sylvestre aqueous extract (1 ml), tincture (1 ml), decoction (2 ml), Centella asiatica aqueous extract (1 ml), tincture (2 ml), decoction (1 ml), Achyranthes aspera aqueous extract (2 ml), tincture (2 ml), decoction (1.50 ml), Tridax procumbens aqueous extract (2 ml), tincture (2 ml) , decoction (1 ml), Terminalia chebula aqueous extract (1 ml), tincture (1 ml), decoction (1 ml), Punica granatum aqueous extract (1 ml), tincture (2 ml), decoction (1 ml), green tea aqueous extract (2 ml), tincture (1 ml) and decotion (2 ml) and 1 ml each of sacred basil oil, lemon grass oil, cinnamon bark oil, clove oil and cardamom oil were selected and added to pH adjusted , pasteurized and liquidized aloe gel juice (25 ml) for gel stabilization. The gel stabilization was thus done using the selected twenty six treatments in a Completely Randomised Design replicated five times and compared with 0.08 per cent sodium benzoate as control and stored for six months. Appearance, colour and odour of all forms of the herbal extracts reduced on storage while those treatments with aromatic oils showed lesser percentage reduction in these parameters. Total solids, amylase and lipase activity decreased on storage. The amino acid content was the highest for liquidized aloe gel juice added with aqueous, tincture and decoction of Achyranthes aspera (0.08 ppm).Vitamin A and C were highest for treatment with green tea leaf aqueous extract which decreased subsequently on storage. An increase in microbial load was observed for all the treatments with herbal extracts from first month of storage. But addition of 1 ml clove oil resulted in stabilization of liquidized aloe gel juice which could be stored upto five months without microbial contamination or affecting the nutritive and sensory parameters. Nutraceuticals were prepared using stabilized liquidized aloe gel juice containing clove oil blended with lemon juice, orange juice and honey in proportions of 50 : 50, 75 : 25 and 90 : 10 followed by pasteurization, flash cooling and stored for 6 months. Appearance, colour and vitamin C were significantly higher for Lemon juice (50 ml) + Liquidized aloe gel juice (50 ml) + 2 ml clove oil while odour, taste, overall acceptability, pH, TSS, carbohydrates and calories were significantly superior for Honey (50 ml) + Liquidized aloe gel juice (50 ml) + 2 ml clove oil. Growth of microbes could be detected from third month of storage for all the treatments. Aloe health drink with honey in the ratio 50 : 50 added with clove oil were selected as the accepted drink which could be preserved for two months without microbial contamination. The preparation of aloe herbal powder by solar drying, air drying, oven drying or freeze drying resulted in a sticky product which could not be reconstituted with distilled water for quality comparison with fresh gel, thus warranting further investigation. The present study revealed that liquidized aloe gel juice pasteurized and mixed with clove oil (4 per cent) is a low cost stabilization method which can be taken as a base material for the preparation of health drink. The nutraceutical with liquidized and stabilized aloe gel juice mixed with equal proportion of honey and preserved with clove oil is a palatable drink having higher calories which could be stored for two months. The dried aloe latex a byproduct produced by shade drying is superior with high aloin content and can also be used for the development of marketable product.ThesisItem Open Access Quality assessment of coconut oil and detection of adulteration(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2020) Rakhi, Jose; KAU; Sreekala, G SThe research programme entitled “Quality assessment of coconut oil and detection of adulteration” was undertaken at the Department of Plantation Crops and Spices, College of Agriculture Vellayani during the period 2018-2020. The study was conducted in order to assess the quality parameters of coconut oil and to detect adulteration by different techniques and to validate an easy and efficient method for the detection. Coconut oil was adulterated with 1, 5, 10, 15, 20 and 30 per cent of palm kernel oil and mineral oil. Apart from this pure coconut oil, pure palm kernel oil, pure mineral oil and five branded coconut oils were also collected altogether contributing twenty samples. These samples were analysed for physical and chemical characteristics, microbial contamination, thin layer chromatography, fatty acid composition by GCMS and FTIR spectroscopy to detect adulteration and to find an easy and efficient method for detection of adulteration. Physical and chemical characteristics analysed revealed refractive index and relative density of pure coconut oil, branded coconut oil and coconut oil mixed up to 30 per cent palm kernel oil were within the codex standard range. The apparent density of pure coconut oil differed significantly from adulterated samples. Insoluble impurities of all the samples were in the range 0.024-0.047 per cent which was within the standard prescribed by Codex (< 0.05 per cent). Saponification value of pure sample and all the branded coconut oil samples showed a value above 250 mg KOH g of oil-1 which was in tune with standard specified by FSSAI. Palm kernel oil and mineral oil as adulterant in different percentage showed less than 250 mg KOH g of oil-1. FSSAI standard for iodine value of coconut oil is in the range 7.5-10g and the iodine value of pure sample and all the branded coconut oil samples tested were within the range 7.5-10g. Iodine value of coconut oil adulterated with 5 per cent palm kernel oil and above exceeded the standard value (10) while adulteration with mineral oil above 1 per cent showed less than 7.5g. Standard Polenske value as prescribed by FSSAI and Codex (not less than13) was noticed in all samples except coconut oil with palm kernel oil 5 per cent and above and all mineral oil combinations. Pure sample, branded coconut oil and coconut oil mixed with varying percentage of palm kernel oil had unsaponifiable value within the limit of standards (not more than 1 per cent) while that of coconut oil mixed with even 1 per cent mineral oil and above exceeded the limit (1.18 per cent). Acid value of not more than 6 was the standard put forward by FSSAI and Codex and all oil samples except palm kernel oil and coconut oil mixed with 15 per cent palm kernel oil and above recorded values above 6. FSSAI standard for peroxide content in fresh coconut oil is below 10 meq/Kg and higher peroxide value were obtained from coconut samples mixed with palm kernel oil at 5 per cent and above and mineral oil at 15 per cent and above. Codex standard for matter volatile at 105°C is < 0.2% and all samples were within the limit. Principal component analysis (PCA) performed on physical and chemical characteristics of oil revealed high coefficient in PC1 for unsaponifiable matter and it contributed to maximum variation followed by relative density, apparent density, Polenske value, refractive index, saponification value and iodine value. In PC2, high coefficient was noticed for acid value followed by peroxide value and iodine value . Microbial contamination assessed by total plate count was within the APCC standard of less than 10 (< 10) colony forming units/ml. Fungal and actinomycete population was however not detected in the oil samples. Thin layer chromatography revealed yellow streaks in the profile of pure coconut oil sample, branded coconut oil samples and coconut oil mixed with different concentrations of palm kernel oil while yellow streaks were absent in coconut oil samples mixed with mineral oil. Gas chromatography coupled with mass spectrometry revealed the fatty acid composition in the oil samples. Principal component analysis carried out to analyze the variation contributed by the fatty acids revealed C16:0, C 12:0 and C 14:0 contributed the maximum variation in PC1. In PC2 high coefficient was noticed for C8:0 and C10:0. Percentage of oleic (C18:1) and linoleic (C18:2) acids were found to increase with increase in concentration of palm kernel oil and fatty acids were not detected in mineral oil. FTIR spectra formed peaks at regions of 2800-2900 cm-1, 1743 cm-1, 1465 cm- 1, 1417 cm-1, 1377 cm-1, 1229 cm-1, 1155 cm-1, 1111 cm-1, 962 cm-1, 722 cm-1 in pure coconut oil sample. Branded coconut oil samples and palm kernel oil adulterated samples obtained peaks at similar regions. Intensity of the peak at 3006 cm-1 increased with increasing concentration of palm kernel oil. The peaks for mineral oil were obtained at 2954 cm-1, 2923 cm-1, 2854cm1, 1466 cm-1, 1378 cm-1 and 721 cm-1. Intensity of the peaks at 1743 cm-1, 1229 cm-1, 1155 cm-1 and 1111 cm-1 were found to decrease with increase in percentage of mineral oil which indicated the absence of carbonyl group in mineral oil. Economics of adulteration of coconut oil by palm kernel oil and mineral oil revealed that maximum of Rs 4800/- per quintal was obtained by adulteration when 30 per cent of coconut oil was substituted by mineral oil followed by 20 per cent mineral oil ( Rs 3200/- per quintal) and 30 per cent palm kernel oil ( Rs 3150/- per quintal). The present study implies that among the physical and chemical parameters, unsaponifiable matter, relative density, apparent density, Polenske value and refractive index could be used to identify the adulteration in coconut oil by mineral oil. Similarly thin layer chromatography could also detect the presence of mineral oil. Saponification value, iodine value and Polenske value could detect the adulteration due to palm kernel oil. The use of FTIR spectroscopic technique is an easy method to identify adulteration in coconut oil through identification of specific peaks. GCMS analysis could provide information about the fatty acid composition.ThesisItem Open Access Standardisation of agro techniques for transplanted ginger ( Zingiber officinale rosc.)(Department of Plantation Crops and Spices, College of Agriculture, Vellanikkara, 2017) Sandra Merin, Mathew; KAU; Sreekala, G Sulches @30,15, and 7.5 t ha -1 (M1,M2,M3 respectively) and plastic mulch (M4). For M1 and M2, half the quantity of organic mulch was applied at the time of transplanting and the remaining at two months after transplanting sub plot treatments were T1(75:50:50kg of NPK ha-1), T2(150:100:100 kg ha-1), T3(T1+foliar application of 19:19:19 @ 0.5% applied at 1,3,4 MAT and T4(100:75:75 kg ha-1+foliar application of 19:19:19 @0.5% applied at 1,2,3 MAT). For all treatment except C2, half N, full P and half K were applied at the time of transplanting and remaining half N, half K applied at two MAT. Two control plots, one with ginger rhizomes planted with recommended nutrient level as per KAU POP (C1) and other absolute control (c2) was also included. Two nodded rhizome bits of ginger cultivar was raised in portrays with Trichoderma enriched coir pith compost and FYM in the ratio 2:1 for treatments except C1, and were transplanted at 11/2-2 months age in beds taken in the interspaces of coconut. FYM @ 30 t ha-1 was applied uniformly to all plots except absolute control. The result revealed that growth parameters like plant height, number of leaves per plant, shoot weight, dry matter production, net assimilation rate, leaf area index, leaf area duration were significantly higher for mulch, M1 (30t ha-1) and fertilizer dose, T2 (150:100:100 kg ha-1 NPK). The yield attributes like fresh yield, dry yield, harvest index, dry recovery, rhizome thickness, rhizome spread were significantly higher for M1 and T2. Considering the treatment interaction increased growth, yield character, uptake of N,P,K, agronomic efficiency of N,P,K were observed with mulching @30 t ha-1 along with a fertilizer of 150:100:100 kg ha-1NPK(m1t2). The quality parameters of ginger rhizome at harvest viz., starch, oil, fibre. Non Volatile Ether Extract ( NVEE) were higher for M1 while for starch and NVEE it was on par with M4. Starch, volatile oil, NVEE and fibre were more for T2 while the volatile oil content in T2 was on par with T4 at the time of harvest. Among combinations m1t2. (mulching @ 30 t ha-1 with 150:100:100 kg ha-1 NPK) significantly increased starch, fibre, oil and NVEE on all stages of observation. The weed count and weed dry weight were significantly low in treatments with plastic mulch. Nutrient balance sheet studies revealed the significance of plastic mulch in reducing the net loss of nutrients. The treatment combination, m1t2 registered higher net profit and B: C ratio. The results of the study indicated that of ginger transplants intercropped in coconut garden, that mulching @ 30 t ha-1(half at transplanting and half 2 MAT) along with 150:100:100 kg NPK ha-1 and basal application of 30 t ha-1 of farm yard manure could be recommended for higher yield, quality and profit. It also resulted in 24 percent increase in dry ginger yield over the conventional method of planting and nutrient application.ThesisItem Open Access Survey, characterization and evaluation of clove (Syzigium aromaticum (L) Merr. and Perry) accessions(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2018) Avinash, M; KAU; Sreekala, G SThe present study entitled “Survey, characterization and evaluation of clove (Syzigium aromaticum (L) Merr. & Perry) accessions” was taken up with the specific objective to characterize and evaluate clove accessions based on morphological and biochemical parameters. The Survey was carried out in the major clove growing plantations of Trivandrum, Kollam and Pathanamthitta districts of Kerala and Kanyakumari district of Tamil Nadu, as these districts harboured the major clove population. Twenty varied accessions were tagged as BRC-1, BRC-2, BRC-3, BRC-4, MRC- 5, MRC-6, MRC-7, MRC-8, AMC-9, AMC-10, AMC-11, AMC-12, AMC-13, MMC-14, MMC-15, BLC-16, BLC-17, BLC-18, MGC-19 and ANC-20 based on the name of the estates/location from where the trees were identified. Twenty one qualitative and thirty four quantitative characters were recorded. Qualitative characters included tree, leaf, bud, flower, fruit and seed characters. Considerable variation was noticed among the accessions for the qualitative characters namely canopy shape, branching pattern, colour of young leaf, colour of mature leaf, leaf lamina shape, leaf apex shape, bud forming season, bud clustering habit, bud size, colour of hypanthium, petal colour, sepal colour, colour of stigma, fruit shape and seed shape. Few characters like leaf arrangement, position of flower, colour of peduncle, mature fruit colour, ripe fruit colour and seed colour were non variable characters among the accessions evaluated. Bivariate analysis of major qualitative characters revealed major association between canopy shape and branching pattern; colour of young leaf and petal colour, sepal colour and colour of stigma; colour of mature leaf and bud size; and fruit shape and seed shape. The multivariate qualitative clustering using UPGMA method resulted in 13 clusters, at default 80% similarity. Quantitative characterisation of bud, flower, fruit, seed and quality parameters summarised based on the descriptive statistics revealed wider range of variability in number of inflorescence per m2 and single bud weight fresh and dry. The quality parameters assessed among the accessions revealed eugenol as the main constituent with a content range of 54.29 to 70.77%. GC MS analysis of the bud oils of the elite clove accessions exhibited 25 constituents, the major being p-eugenol, eugenyl acetate, β-caryophyllene, β-cubebene and α-humulene. The principal component analysis undertaken reduced the thirty two quantitative characteristics to two principal components accounting for 88.8% of total variation. Stem girth at 45 cm height, and single bud weight, fresh and dry; displayed high correlation with the first axis while number of inflorescence per m2 highly influenced the second axis indicating that these characters have an important role in clustering of clove accessions. A score plot generated based on the first two principal components using Minitab version 18 identified fourteen clusters. The parallelism between qualitative and quantitative clusters resulted in intuitive perceived quantitative characterisation, which tells the extent to which one can conceive the quantitative characters of clove based on easily identifiable qualitative characters. The linkage of characters analysed based on the biplot of component loadings revealed strong positive association between all the quantitative characters measured except girth at 45 cm height, number of branches, number of inflorescence per m2, single bud weight (fresh), single bud weight (dry) and fresh bud yield per tree. A near zero correlation was observed between number of inflorescence per m2 and single bud weight (fresh) and single bud weight (dry) as indicated by the perpendicular of the vectors. The results of the study indicated that by observing the qualitative characters and the minimum data set characters in the bearing season, one can optimally sort out the ideotype clove accessions. Identification of an ideotype using existing data revealed accessions BRC-1, MRC-5, MRC-6 and BRC-3 as ideotypes and thus can be suggested as elite accessions for further study and breeding work.ThesisItem Open Access Variability in ginger(Zingiber officinale rosc) for yield and resistance to rbizome rot(Department of Plantation Crops and Spices, College of Agriculture, Vellayani, 2019) Anargha, T; KAU; Sreekala, G SA field experiment entitled “Variability in ginger (Zingiber officinale Rosc.) for yield and resistance to rhizome rot” was conducted at Department of Plantation Crops and Spices, College of Agriculture, Vellayani during 2017-2019 with the objective to evaluate ginger genotypes for yield and resistance/tolerance to rhizome rot. The study on variability in ginger (Zingiber officinale Rosc.) for yield and resistance to rhizome rot was conducted as two experiments (i) Collection of ginger genotypes and analysis for genetic variability and yield (ii) Screening of ginger genotypes against rhizome rot under natural condition. Twenty genotypes of ginger collected from different regions of Kerala and a control variety Aswathy were planted in Instructional Farm, College of Agriculture, Vellayani in a randomized block design with four replications. Qualitative characterization of the genotypes was carried out based on DUS guidelines. Plant growth habit of collected genotypes included erect and semi-erect types. All the genotypes were short type (height<100cm) with short leaf length (<25cm), medium leaf width (2.5-3.5cm) having few (<10) and medium (10-15) shoots. The intensity of shoot colour noticed was green and dark green while that of leaf were light green, green and dark green. The leaf petiole length was short (<0.5cm) for all the genotypes except T17 (Kalliyur). Spikes were formed only in three genotypes of which two had crimson bract tip and other had yellowish white tip. Rhizome thickness was thin (<2cm) for all genotypes except T11 (Kazhakootam) with medium (2-3cm) thickness with straight, curved and zigzagged rhizome shape. Greyish yellow rhizome skin colour was predominant while the flesh colour were light yellowish grey, greyish yellow and yellow. The collected genotypes sprouted from 7 days after planting and continued upto 20 days after planting. Plant height was significantly superior for T12 (Irinjalakkuda) while the number of tillers and dry matter content was significantly higher for T11 (Kazhakootam) at 7 MAP. Leaf area for T8 (Karunagapally) was 48.2 cm2 which was significantly higher and on par with T12 (Irinjalakkuda) which had 47.96 cm2 at 7 MAP. Rhizome spread (13.91 cm), rhizome thickness (2.02 cm) fresh weight per plant (0.150 kg plant-1) fresh weight per plot (2.33kg plot-1), dry weight per plant (0.031kg plant-1), dry weight per plot (0.475kg plot-1) and harvest index (0.60) were significantly higher for T11 (Kazhakootam). Dry recovery, starch content and oleoresin were significantly superior for T12 (Irinjalakkuda). Crude fibre content of T16 (Pozhuthana) was significantly higher (5.75 %) while the essential oil content (2.42 %) was significantly higher inT20 (Thalavur). Significant variation existed among the genotypes for characters such as plant height, number of tillers, leaf area, rhizome spread, rhizome thickness and oleoresin. Phenotypic coefficient of variation (PCV) was a little bit higher than the genotypic coefficient of variation (GCV) indicating that environment played very little role in the expression of the characters. Crude fibre registered highest GCV (44.36) and PCV (44.84). High heritability coupled with high genetic advance was observed for rhizome yield, oleoresin, phenol, crude fibre, rhizome thickness and essential oil. Yield per plant was found to be significantly and positively correlated with plant height, number of tillers, leaf area, rhizome spread, rhizome thickness and oleoresin content. Path analysis revealed that leaf area, number of tillers and rhizome spread had maximum positive direct effect on yield per plant. Ginger genotypes screened against rhizome rot using cultures of Pythium aphanidermatum under natural condition revealed increased phenol, polyphenyl oxidase, lipoxygenase and phenylalanine ammonia lyase activity in all genotypes after inoculation. Peroxidase activity was higher for genotypes of lower disease severity while it decreased for genotypes with higher disease severity. The percentage disease incidence and disease severity were significantly lower for T1 (Mananthavady) and was on par with T12 (Irinjalakkuda). Soil temperature ranged from 25.3ºC to 29.7ºC while maximum temperature varied from 29.2ºC to 32.4ºC, minimum temperature from 24.9ºC to 26ºC, relative humidity from 93% to 98 % and rainfall from 2.5cm to 28.3cm during the period of symptom development. The ginger genotypes evaluated revealed higher yield for T11 (Kazhakootam) followed by T15 (Nedumkandam) which produced 65.27 and 20.87 percent yield increase over control. Quality parameters such as starch, oleoresin and dry recovery was significantly superior for T12 (Irinjalakkuda) suggesting the suitability of the genotype for dry ginger. Screening the ginger genotypes for rhizome rot under natural condition, revealed less disease severity in T1 (Mananthavady) and T12 (Irinjalakkuda). The genotype T11 (Kazhakootam) developed from the present study can thus be used for further evaluation for green ginger production, and T12 (Irinjalakkuda) for dry ginger production and resistance/tolerance to rhizome rot.