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ThesisItem Open Access Optimizing propagation techniques in neelayamari (Indigofera tinctoria L.)(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 2019) Mekha Mariam, Abraham; KAU; Krishnakumary, KIndia is acknowledged as one of the world’s richest treasure trove of medicinal plants. Neelayamari (Indigofera tinctoria L.) commonly known as ‘Indian indigo’, is a commercially grown leguminous plant of medicinal importance. The extract of the leaves is reported to have remarkable effect on hair growth and in preventing juvenile greying of hair. Due to the presence of many worthy phytochemicals, the crop is being documented in ‘Ashtangahridaya’ and is being cultivated by several pharmaceutical entrepreneurs, both in public and private sector. Like most of the medicinal plants, the cheapest method of propagation of this crop is through seeds. However, poor germination and vigour of seeds is a major problem in Neelayamari. In addition, heavy loss in seed yield occurs due to the splitting of pods at maturity. The study ‘Optimizing propagation techniques in Neelayamari (Indigofera tinctoria L.)’ was conducted in the Department of Plantation crops and Spices, with the objectives of standardizing the physiological maturity stage in Indigofera tinctoria L. for seed harvest, presowing seed treatments to enhance seed quality and longevity and vegetative propagation technique in Indigofera tinctoria L. through stem cuttings. In order to assess the stage of attainment of physiological maturity for seed harvest in Neelayamari, flowers were tagged on the day of anthesis and the pods were harvested at five days interval from 30 days of anthesis up to the pod splitting stage (63 days after anthesis). It was observed that the values of pod, seed and seedling characters increased up to 45 days after anthesis to reach their highest and thereafter declined till the pod splitting stage (63 days after anthesis). Germination and vigour indices at 45 days after anthesis were 73.80 per cent, 485 and 294 respectively and those at the pod splitting stage were found to be 31.33 per cent, 132 and 65 respectively. Hence, it was inferred that the seeds of Neelayamari reached physiological maturity stage by 45 days after anthesis. The seeds harvested at physiological maturity were dried to 8 per cent moisture content and subjected to various seed treatments before being packed in 700 gauge polyethylene bags. Untreated seeds served as the control. The seeds were stored under ambient conditions upto six months. The scarification treatments included treatment with Conc. H2SO4 for 5, 10 and 15 minutes, mechanical scarification with sand, hot water treatment at 80oC for 20 minutes and 60oC for 30 minutes and hydration for 24 hours. The quality parameters of the stored seeds were recorded at monthly intervals during the storage period and were put for germination test in sterilized sand media. Results pointed out that most of the seed treatments were effective in enhancing germination. High initial germination was recorded in mechanically scarified (95.83 %) and hydrated seeds (93.27%), while the untreated seeds showed a germination of 74.33 per cent. Vigour index I (703 and 698 respectively) and II (430 and 428 respectively) were also the highest in these treatments. Seed treatment with sulphuric acid, however, proved to be detrimental. Seed treatment also helped in extending the viability of the seeds. Mechanically scarified and hydrated seeds retained their germination above 60 per cent for six months during storage (65.67% and 63.67% respectively), while, in untreated seeds, germination reached 61.33 per cent at four months of storage and declined to 44.34 per cent by six months of storage. Seeds treated with sulphuric acid never attained the germination of sixty per cent throughout the storage period and those treated with sulphuric acid for 15 minutes failed to germinate at sixth month of storage. EC was found to be the lowest in hydrated seeds (0.0011 dSm-1) and mechanically scarified seeds (0.0012 dSm-1). The results thus indicated that mechanical scarification of seeds or hydropriming for 24 h can not only improve seed germination and seed quality but also prolong the longevity of the seeds. It was also noticed that all the seed quality parameters declined along the storage period. Attempt to assess the possibility of vegetative propagation in Neelayamari was carried out using hardwood, semi-hardwood and softwood cuttings, exposed to varying doses of IBA (250 ppm, 500 ppm, 750 ppm, 1000 ppm, 1500 ppm, 2000 ppm and 2500 ppm) and charcoal slurry dip. The cuttings were planted in polythene bags and were maintained in a mist chamber. Initially, the experiment was conducted during summer season and only the softwood cuttings treated with 2000 (8.89%) and 1500 ppm IBA (5.53%) survived after 60 days of planting, while all others withered and dried off. The experiment was then repeated during rainy season and the best results were obtained in the season. Softwood cuttings treated with 2000 ppm IBA during rainy season exhibited early sprouting (7.18 days) and a field establishment of 70.67 per cent. In comparison, the semi-hardwood and hardwood cuttings exhibited very low establishment rates of 21.77 per cent and 17.90 per cent respectively. Hence, it was evident that vegetative propagation using softwood cuttings treated with 2000 ppm IBA during rainy season can be relied upon as an alternative propagation method in Neelayamari.ThesisItem Open Access Stock scion interaction in Piper nigrum L. grafts(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 2019) Sarga George; KAU; Sujatha, V SBlack Pepper (Piper nigrum L.) also called ‘King of Spices’ and ‘Black Gold’, is one of the most widely used spices in the world, occupying a position that is supreme and unique. India is one among the countries where black pepper is being widely cultivated. However our productivity is low compared to other pepper producing countries in the world. Among the various factors limiting the productivity of Indian pepper, a soil borne disease called foot rot caused by Phytophthora is of prime importance. Piper nigrum is highly susceptible to Phytophthora foot rot. It has been reported that some South American Piper spp. are immune to Phytophthora. Interspecific crossing between Piper nigrum and immune species has not been successful so far. Grafting on resistant rootstock is a method to escape soil borne inoculum. The present study was conducted to assess the stock and scion interaction in grafts of Piper nigrum L. on different South American species of Piper immune to Phytophthora foot rot and to standardize the best time of grafting. The study was carried out as three experiments, viz., grafting studies, anatomical studies on Piper species and anatomical studies on graft union at different stages of development. Orthotropic as well as plageotropic shoots of P. nigrum, variety Panniyur 1 was grafted on three South American Piper species viz., P. colubrinum, P. auduncum and P. arboreum. Grafting of Piper nigrum on the same species was also done to study the feasibility of such grafting. The trial was laid out in completely randomized design. When orthotropic shoot of P. nigrum was used as scion, highest grafting success was recorded by the grafts of P. nigrum on the same species (100%) followed by the grafts on P. colubrinum (96.66%), P. auduncum (66.66%) and P. arboreum (46.66%). Graft survival after one year of grafting was 90.00, 83.33 and 33.33 per cent for P. nigrum/P. nigrum, P. nigrum/ P. colubrinum and P. nigrum/ P. auduncum grafts respectively. Survival of P. nigrum grafts on P. arboreum was very limited. None of these grafts survived for more than three months after grafting. Irrespective of rootstocks, the best month identified for grafting orthotropic shoot of P. nigrum was March. Although, self grafts showed highest per cent success in grafting, based on the growth of grafted plants (six month old), grafts on P. colubrinum was found to be the best with highest plant height (120.55 cm), number of nodes (18.91) and internodal length (6.32 cm). The graft recovery was less when plageotropic shoot of P. nigrum was used as scion. The highest per cent success was recorded by the grafts of P. nigrum on the same species (93.33%) followed by the grafts on P. colubrinum (66.66%), P. auduncum (36.66%) and P. arboreum (26.66%). March was identified as the best month for grafting plageotropic shoot of P. nigrum on P. nigrum, P. auduncum and P. arboreum. However, grafts on P. colubrinum performed best when grafted during June. Graft survival after one year of grafting was 66.66, 30 and 16.66 per cent for P. nigrum/P. nigrum, P. nigrum/ P. colubrinum and P. nigrum/ P. auduncum grafts respectively. Survival of P. nigrum grafts on P. arboreum was very limited. As far as the growth of grafted plants was concerned, highest growth was shown by the grafts of P. nigrum on the same species. In the anatomical studies of Piper spp. it was observed that, Piper species exhibited a peculiar arrangement of vascular bundles. Two rings of vascular bundles comprising of an outer, cortical and an inner, medullary bundles were observed in all the four Piper species examined. Mucilage canal was present only in P. nigrum while an additional medullary bundle was observed in P. colubrinum. Large pith region was the characteristic feature of P. auduncum and P. arboreum. Examination of graft union at three, six and twelve months after grafting revealed that, graft union formation was completed by six months after grafting. One year old P. nigrum/ P. colubrinum grafts and P. nigrum/ P. auduncum grafts exhibited the formation of a dense necrotic area at the graft interface. Based on the observations, it can be concluded that, due to the peculiar arrangement of vascular bundles in Piper species, matching of all the vascular bundles of stock and scion is difficult. However, complete union of parenchymatous tissues of stock and scion was formed within six months after grafting. But, a proper cambial connection between the grafting partners was not evident. Further studies need to be conducted to find out the reasons for the development of dense necrotic area at the graft interface.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 Salicylic acid mediated metabolite elicitation and growth responses in long pepper (Piper longum L.)(Department of plantation crops and spices, college of agriculture, Vellayani, 2019) Krishna Veni Harish; KAU; Deepa S NairA study on “Salicylic acid mediated metabolite elicitation and growth responses in long pepper (Piper longum L.)” was carried out at the Department of Plantation Crops and Spices, College of Agriculture, Vellayani, Thiruvananthapuram, Kerala during 2017-19. The study aimed at assessing the effect of different concentrations of salicylic acid on plant growth, yield and metabolite production in P. longum. The rooted cuttings from the promising variety of long pepper, Viswam plants were exposed to nine foliar spray treatments with varying salicylic acid (SA) concentrations and control treatments viz, SA 0.1 mM (T1), SA 0.5 mM (T2), SA 1.0 mM (T3), SA 1.5 mM (T4), SA 2.0 mM (T5), SA 2.5 mM (T6), ethanol (0.20 per cent) spray (T7), water spray (T8) and control (T9) at 2, 4 and 6 months after planting (MAP). The study was conducted in completely randomized block design (CRD) with three replications. The plant growth parameters, metabolite production, physiological parameters, yield parameters and major nutrient uptake in response to various foliar spray treatments were studied. The plant growth parameters viz., plant height, number of leaves, leaf area, number of primary branches, number of spike bearing branches and shoot weight per plant (fresh and dry weight) were recorded at 3, 5 and 7 MAP. The foliar treatment with SA 0.1 mM (T1) recorded significantly higher values with respect to plant height, number of leaves, leaf area and shoot weight at all stages of observation. All these parameters showed a decreasing trend with increasing concentration of SA. However, no significant variation among the treatments was observed with respect to the number of primary branches and spike bearing branches. The days to emergence of spike and to flowering varied significantly among the treatments tried. SA 0.1 mM (T1) showed earliness with respect to spike emergence (75 days) and flowering (22.67 days). However, the higher concentration took more number of days to emergence of spike (84.67 days) and to flowering (27 days), which was found to be on par with the foliar spray treatments devoid of SA. However, the days from emergence to maturity of spike did not show any significant variation among the treatments. The plant metabolites, viz., total chlorophyll, total proteins and defense enzymes (peroxidase, catalase and superoxide dismutase) at 3, 5 and 7 MAP, recorded significantly higher values in plants subjected to foliar spray with SA 0.5 mM (T2). The mature dark green oven dried spikes were analysed for carbohydrates, piperine, volatile oil and oleoresin content, which varied significantly among the different treatments. The treatment, T2 recorded significantly higher carbohydrate, starch and sugar contents. The same treatment reported the highest values with respect to piperine (1.15 per cent), volatile oil (1.32 per cent) and oleoresin (14.21 per cent) content. This treatment gave approximately 30 per cent increase in piperine content, 12 per cent increase in volatile oil and oleoresin content over the control. However, at higher concentration of SA, T6 (SA 2.5 mM), piperine content (0.90 per cent) was found to be significantly lower and on par with foliar spray treatments devoid of SA. The physiological parameters at 3, 5 and 7 MAP, showed significant variation with regards to the foliar treatments. The foliar spray treatment with SA 0.1 mM (T1) recorded significantly higher values with respect to dry matter production, leaf area index, stomatal conductance and photosynthetic rate at all the stages of observation. The physiological parameters viz., NAR, cell membrane stability index and proline recorded significantly higher values in T2 at all stages of observation. The yield parameters viz., number of spikes, fresh and dry spike yield, fresh and dry root yield and root length varied significantly with different foliar spray treatments. With respect to number of spikes (177.33), fresh (133.88 g) and dry (25.81 g) spike yield, T1 recorded significantly higher values. T1 was found to be on par with T2 with respect to dry spike yield. The root parameters such as fresh (30.15 g) and dry (12.15 g) root yield and root length (70.61 cm) were significantly higher in treatment T2. With regards to dry root yield, T2 was found to be on par with T1. However, harvest index, spike length, spike girth and driage did not showed any significant variation among the treatments. The nutrient uptake by the crop was studied and the results revealed that the plants exposed to T1 showed significantly higher uptake of N (1.27 g plant-1). However, with respect to P (0.059 g plant-1) and K (1.78 g plant-1), treatment T2 recorded higher values. In the study, it was observed that SA 0.1 mM (T1) gave better performance with respect to plant growth parameters and physiological parameters followed by SA 0.5 mM (T2). Foliar spray with SA 0.5 mM gave superior performance with respect to plant metabolites, while high spike and root yield were recorded in foliar spray with SA 0.1 mM and 0.5 mM. Hence, it can be inferred from the study that foliar spray with either concentration of SA 0.1 mM and 0.5 mM. at 2, 4 and 6 MAP could effectively elicit plant growth, yield and metabolite production in Piper longum.ThesisItem Open Access Chitosan mediated metabolite elicitation and growth responses in kasthuri turmeric(curcuma aromatica)(Department of plantation crops and spices, college of agriculture, Vellayani, 2019) Nivya J Thengumpally; KAU; Deepa S NairThe present investigation entitled “Chitosan mediated metabolite elicitation and growth responses in kasthuri turmeric (Curcuma aromatica Salisb.)” was conducted at the Department of Plantation Crops and Spices, College of Agriculture, Vellayani during 2017-2019 with the objective to study the effect of different concentrations of chitosan on plant growth, yield and metabolite production in Curcuma aromatica. The planting material for the study was obtained from Instructional Farm, College of Agriculture, Vellayani. The experiment was laid out in completely randomized block design (CRD) with nine treatments and three replications. The treatments consisted of foliar spray with different concentrations of chitosan and control treatments viz., chitosan 0.5 g l-1 (T1), chitosan 1 g l-1 (T2), chitosan 1.5 g l-1 (T3), chitosan 2 g l-1 (T4), chitosan 2.5 g l-1 (T5), chitosan 3 g l-1 (T6), acetic acid (0.25 per cent) spray (T7), water spray (T8) and control (T9). The treatments were given at 3 and 5 months after planting (MAP). The plant growth parameters viz., plant height, number of tillers, number of leaves, leaf area and shoot weight were recorded at 4 and 6 MAP. All chitosan foliar spray treatments resulted in significantly taller plants compared to treatments devoid of chitosan at 6 MAP, with the highest value (109.91 cm) in T6. T5 and T6 recorded significantly higher number of leaves at 4 MAP while at 6 MAP, it was recorded in treatments, T2 to T6. Similar trend was observed with leaf area also. T4 to T6 recorded significantly higher shoot weight at 4 MAP and T5 to T6 at 6 MAP. The highest dry weight (42.69 g) was recorded in T5 and 63.0 g in T6 at 4 MAP and 6 MAP, respectively. Number of tillers did not show any variation among treatments at both stages of observation. The plant growth parameters viz., rhizome spread, rhizome thickness, number of fingers, root length, root spread and root weight were recorded at 4 MAP, 6 MAP and at harvest. Significant enhancement in rhizome spread was observed only at harvest, in T6, which was on par with T5. The higher concentrations of chitosan foliar spray significantly influenced rhizome thickness at 6 MAP and at harvest; significantly higher values were observed in treatments, T2 to T6 at 6 MAP and T3 to T6 at harvest. At all stages of observation, number of fingers was found to be significantly higher in T5 and T6. Root length and root spread were significantly higher with the treatments T5 and T6 at 6 MAP and at harvest. Significant variation in root weight was observed in C. aromatica only at 6 MAP. The observations on plant metabolites viz., chlorophyll content, total proteins and defence enzymes were recorded at 4 and 6 MAP. T4, T5 and T6 were observed to have significantly higher chlorophyll content among the treatments, at 6 MAP. Total proteins and defense enzymes were observed to give significant variation at both stages of observation. Protein content was found to be significantly higher (6.89 mg g-1) in T5 at 4 MAP and in treatments T4 to T6 at 6 MAP, the highest value being recorded in T6 (8.46 mg g-1). Catalase and peroxidase activity were found significantly higher in T5 and T6 at both stages of observation. SOD activity was found to be significantly higher in T6 at 4 MAP and T4 to T6 at 6 MAP. The observations on curcumin content, volatile oil, oleoresin and carbohydrate content were recorded at harvest. Curcumin, volatile oil and oleoresin was observed to be significantly higher in treatments T4, T5 and T6. T5 and T6 recorded significantly higher carbohydrate content among the various treatments tried. The physiological parameters viz., leaf area index (LAI), stomatal conductance, photosynthetic rate, proline content and cell membrane integrity (CMI) were recorded at 4 and 6 MAP. LAI was found to be significantly higher in treatments T5 and T6 at 4 MAP and T2 to T6 at 6 MAP. With respect to stomatal conductance, T4, T5 and T6 gave significantly higher values at both, 4 and 6 MAP. T6 recorded significantly higher photosynthetic rate among the treatments tried at both stages of observation. All foliar spray treatments with chitosan recorded significantly higher proline content at 4 MAP and T4 to T6 at 6 MAP. CMI was found to be significantly superior in T3 to T6 at 4 MAP, but did not show any variation at 6 MAP. The dry matter production was recorded at 4 MAP, 6 MAP and at harvest. The highest dry matter production was obtained in T6 at all stages of observation and was comparable with T5. The foliar spray treatments did not show any significant variation with respect to net assimilation rate during the period between 4 and 6 MAP. The chitosan foliar spray significantly influenced the rhizome yield, crop duration and harvest index of C. aromatica. T5 (170.95 g plant-1) and T6 (173.27 g plant-1) were found significantly superior to all other treatments with regard to rhizome yield. Crop duration and harvest index of plants exposed to chitosan foliar spray were found to be significantly superior to those devoid of chitosan. Uptake of major plant nutrients (N, P and K) were found to be maximum in T5 and T6. In the present study, chitosan application at different concentrations as foliar spray at 3 and 5 MAP elicited plant growth, production of curcumin, volatile oil, oleoresin and yield. The chitosan concentration of 2.5 and 3 g l-1 gave maximum enhancement in the yield and metabolite production.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.ThesisItem Open Access Priming seed rhizome to enhance growth and yield of transplanted ginger (Zingiber officinale Rosc.)(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 2018) Dharini Chittaragi; KAU; Jalaja, S MenonIn Kerala, ginger is cultivated as a rainfed crop, usually planted during April - May and harvested during December - January with a subsequent storage of seed rhizome for a period of 3 to 4 months to raise the next crop. Raising a transplanted ginger crop can decrease seed rate to 500-700 kg per hectare from1500 kg per hectare, reducing the cost of cultivation. Yield from rhizome sprouts of 3-5 g used as transplants is reported to be on par with the conventional system of direct planting of 20 g rhizome seed. Bio-priming ginger rhizome before transplanting was also found to be beneficial in increasing the yield of off-season green ginger. Hence, the present study was conducted to analyze the performance of primed portray transplants of ginger at various planting times. The experiment was conducted in Department of Plantation crops and Spices, College of Horticulture, Vellanikkara using seed rhizomes of variety Aswathy. The research work was grouped into three experiments viz., studies of seed rhizomes during storage, effect of priming on ginger transplants in the nursery and field performance of primed protray raised ginger transplants. Studies on seed rhizome revealed that, a weight loss of 28 per cent was recorded in the seed rhizomes stored in Zero Energy Cool Chambers for three months (February to May 2017). Seed rhizome buds varied in length from 0.847μm to 2.19μm and breadth from 1.19 μm to 0.703μm before storage and at three months after storage respectively. Histochemical comparison of the rhizomes showed that the size of starch grain decreased from 40μm to 20 μm and the size of oil globules increased from 20 to 40 μm on three months’ storage. The performance of primed protray raised ginger transplants in nursery was assessed with 13 treatments during four planting times viz., February, March, April and May to identify the optimum planting time and priming treatment for seed rhizomes. The study revealed that, priming had influence on survival rate. The mean survival per cent of seed rhizomes planted in May (3MAS) was found to be superior (58.89%) to all other planting times irrespective of the priming treatments. The survival per cent of seed rhizome planted immediately after harvest (February) was the least (11.6%). However, the survival of seed rhizomes was found to increase drastically to 50.3 per cent and 50.1per cent during March (1 MAS) and April (2 MAS) respectively. In pooled analysis, seed rhizome primed with Ethephon 200 ppm performed better to all other priming treatments with a survival rate of 68.66 per cent irrespective of planting season. In transplants raised in March and April, priming with Ethephon 200 ppm was found to be superior with high survival per cent (96.9 and 99.0 % respectively). However in May, seed rhizomes primed by soaking in water for one hour (88%) was on par with soaking in water for half an hour (84.03%). These transplants were field planted at 45 days after sowing in nursery to polybags under partial shade at four planting time’s viz., March, April, May and June. The fresh rhizome yield was superior in transplants planted in the month April (451.83g/p) irrespective of priming treatments. In pooled analysis, the fresh rhizome yield from seed rhizome primed with Ethephon 200ppm (372.33g/p) was superior irrespective of planting seasons. Other priming treatments viz., Humigration (340.21g/p), Trichoderma viridae (343.89g/p), Pseudomonas fluorscens (340.2g/p), Trichoderma viridae + Pseudomonas fluorscens combination (335.94 g/p) and soaking in water for 1 hour (355.62g/p) were also on par with that of Ethephon 200 ppm with respect to fresh rhizome yield. The quality parameter like oil, oleoresin and crude fibre varied according to the planting season. Irrespective of the priming treatments, the oil content was high in the crop raised during March (1.42%). Priming with a combination of Trichoderma viridae + Pseudomonas fluorscens (0.96%), Hydropriming (0.86%), Humigration (0.91%) and Pseudomonas fluorscens (0.87%) were also superior in rhizome oil content, irrespective of planting time. The result indicated that to obtain maximum fresh rhizome yield, the optimum time of raising nursery is March (1 MAS) using seed rhizomes primed with Ethephon 200ppm. Seed rhizomes primed with Pseudomonas fluorscens, Trichoderma viridae, Humigration and Soaking in water can also be recommended considering the higher fresh rhizome yield and survival per cent in the nursery with a low seed rate.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 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.