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Open Access
Extraction and utilization of anthocyanin pigments from jamun ( Syzygium cumini L. )
(Department of Processing Technology, College of Horticulture, Vellanikkara, 2016) Naresh, N; KAU; Sheela, K B
The project entitled “Extraction and utilization of anthocyanin pigments from jamun (Syzygium cumini Skeels.)” was undertaken at the Department of Processing Technology, College of Horticulture, Vellanikkara during 2013-15. The objectives of the study were standardization of method of extraction of anthocyanin pigment and evaluation of pigment stability to pH, light, temperature, storage conditions and in processed products. Method for extraction of anthocyanin pigments from jamun was standardized. Among the four extraction methods compared, highest content of anthocyanin (61.07mg/100g), recovery per cent (13.75), colour hue (1.30) and colour intensity (1.13) were obtained for acidified solvent extraction method (20% ethanol + 0.5% citric acid). The effect of light and storage conditions on pigment stability was evaluated. Storage in amber coloured bottles under refrigerated conditions was found to be best for anthocyanin pigment due to lesser degradation of the pigment compared to that stored under ambient conditions. The effect of temperature on the anthocyanin content was studied at 70, 80 and 900 C and anthocyanin content was measured at intervals 30 minutes, 45 minutes and one hour of incubation at each temperature. Anthocyanin content decreased from an initial value of 61.25mg/100g to 50.24mg/100g one hour of heating at 900 C. The effect of pH on stability of anthocyanin pigment was studied at different pH ranging from 2.5 to 7 and incubating it for different intervals from one hour to 20 days at room temperature. Anthocyanin content was found to decrease with increase in pH and the least decrease was found at pH 2.5. Anthocyanin content was found to decrease from an initial value of 61.25mg/100g to 34.28mg/100g 20 days after incubation at a pH of 7. Least changes in pH were observed in RTS beverage prepared with 0.3% citric acid and 0.01% ascorbic acid and stored at refrigerated condition (T10). Acidity of the RTS beverage followed an increasing trend during storage, greatest change in acidity was observed in T8 (product coloured with synthetic colour). Ascorbic acid was found to decrease with increase in duration of storage, minimum changes in ascorbic acid was observed in RTS beverage prepared with 0.4% citric acid and 0.02% ascorbic acid and stored at refrigerated condition (T14). RTS beverage stored under refrigerated conditions retained colour throughout the storage period as compared to ambient condition where there was a greater loss of the colour. Addition of ascorbic acid was found to hasten the colour degradation of the beverage under ambient conditions, but under refrigerated conditions there was not much change in colour. Pigment stability in mixed fruit jam was also studied by storing the prepared product under ambient and refrigerated conditions for a period of three months. pH of the mixed fruit jam followed a declining trend during storage, least change in pH was observed in T1 (control under refrigerated condition) during storage. There was no significant change in the colour of the mixed fruit jam stored under refrigerated conditions. A slight darkening of the colour was seen in the bottles stored at ambient condition. Guava RTS beverage and mixed fruit jam was organoleptically evaluated by selected panel of judges. The products kept under refrigerated conditions recorded highest scores for flavour, texture, taste and overall acceptability compared to those kept at ambient conditions three months after storage.
Open Access
Seed invigoration to overcome dormancy in ash gourd (Benincasa hispida (Thunb.) Cogn.)
(Department of Seed Science and Technology, College of Horticulture, Vellanikkara, 2016) Shobha, K V; KAU; Rose Mary, Francies
An experiment ‘Seed invigoration to overcome dormancy in ash gourd (Benincasa hispida (Thunb.) Cogn.),’ was conducted during 2014-2016 in the Department of Seed Science and Technology, College of Horticulture, Kerala Agricultural University (KAU), Vellanikkara, Thrissur, following a completely randomized design with 16 treatments and three replications. The experiment aimed to elucidate the effect of seed invigoration on dormancy in ash gourd, to ascertain the anatomical changes in seed coat on seed treatment and to assess the storage potential of treated seeds under ambient conditions. Seed invigoration was resorted to by soaking seeds of variety KAU Local in water (hydro priming) for 24 hours, thiourea (0.5%) for 24 hours, KNO3 (0.4%) for 24 hours, KNO3 (0.7%) for 24 hours, KH2PO4 (10-1 M) for 24 hours, vinegar (pH 3.7) for 2 hours, polyethylene glycol 6000 (-0.5 MPa) for 24 hours, salicylic acid (60 ppm) for 12 hours, salicylic acid (60 ppm) for 24 hours, kinetin (10 ppm) for 12 hours, kinetin (10 ppm) for 24 hours, CaCl2 (50 mM) for 12 hours, CaCl2 (50 mM) for 24 hours, Psuedomonas fluorescens (1x106 cfu.ml-1) for 12 hours, Psuedomonas fluorescens (1x106 cfu.ml-1 ) for 24 hours. Untreated seeds served as control (T16). Both treated and untreated seeds, dried to < 8 per cent moisture content were packed in polythene bags (400 guage) and stored under ambient conditions upto ten months. The seed quality parameters viz., germination, germination index, coefficient of velocity of germination, energy of germination, mean time to germination, vigour indices I and II, and electrical conductivity of seed leachate were recorded at monthly intervals during storage. Seed microflora as well as histochemical studies to analyse the changes occurring in the dimensions of embryo and proportions of different fractions of seed coat were assessed at bimonthly intervals. Results pointed out the existence of significant differences in the impact of various invigoration treatments on the seed quality and histochemical parameters observed both within 35 days of invigoration as well as during storage. Majority of the seed invigoration treatments were effective in breaking dormancy in ash gourd. Dormancy was first broken in seeds treated with KH2PO4 and kinetin. In the above treatments germination reached above 60 per cent (the minimum standards for seed certification (MSCS) prescribed for ash gourd) on the 11th day after invigoration (DAI). Dormancy in untreated seed was broken only on the 35th day after extraction. However, seed invigoration with salicylic acid, vinegar and PEG 6000, proved to be detrimental. Seed invigoration also helped in extending the viability of seeds. Germination in seeds treated with CaCl2 for 24 hours, was found to be retained above MSCS for seven months during storage, whereas, in untreated seeds, germination above 60 per cent was observed for two months only. Seeds treated with salicylic acid failed to germinate by 35th DAI while those treated with vinegar and polyethylene glycol (PEG) failed to attain MSCS throughout the period of study. The viability of seeds treated with kinetin or CaCl2 for 12 hours and those treated with Pf for either 12 or 24 hours was found to be retained for six months of storage. Germination index, coefficient of velocity of germination, energy of germination, vigour indices I and II in both treated and untreated seeds, increased by 35th DAI and marginally decreased over the period of storage. In all the invigoration treatments, the above mentioned parameters were invariably higher than that of untreated control. However, the performance of seeds treated with salicylic acid, vinegar and PEG 6000 was lower than the untreated seeds. Invariably, the germination index, coefficient of velocity of germination, energy of germination, vigour indices I and II were high in seeds treated with CaCl2 for 24 hours followed by treatment with Pf for 12 hours and CaCl2 for 12 hours. The mean time to germination, electrical conductivity of seed leachate, the thickness of seed coat and its component layers as well as the microbial infection of seed was also observed to be low in these treatments. High and significant positive correlation was found to exist between germination and speed of germination, coefficient of velocity of germination, vigour indices I and II. It became evident that germination in ash gourd will be strongly affected with an increase in thickness of total seed coat or its outer layerthe testa. The thickening of seed coat owing to the thickening of testa will be accompanied with an obvious decrease in germination, germination index and coefficient of velocity of germination, vigour indices I and II. Results thus indicated that poor germination in seeds of ash gourd may be due to water impermeable seed coat (physical dormancy) mainly resulting from thickening of the outer layer (testa). Such dormancy in ash gourd can be best overcome by seed invigoration with CaCl2 (50 mM) for 24 hours. In addition, enhancement of seed viability, seed quality and seedling performance over storage was also achieved. Seed treatment with CaCl2 (50 mM) or Psuedomonas fluorescens (1x106 cfu.ml-1), for 12 hours were found to be the next best to treatment with CaCl2 (50 mM) for 24 hours. Hence, these can also be recommended for breaking dormancy and maintaining high seed quality in ash gourd.
Open Access
Characteization and evaluation of nutmeg (Myristica fragrans Houtt.) accessions
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 2016) Vikram, H C; KAU; Mini Raj, N
Nutmeg (Myristica fragrans Houtt.) is an introduced crop to India. There exists tremendous variability in the nutmeg population in Kerala, which is the major nutmeg growing state in the country. Assessment of the existing variability is a prerequisite for taking up successful crop improvement programmes, which is very much limited in this tree spice. In this context, the present study entitled “Characterization and evaluation of nutmeg (Myristica fragrans Houtt.) accessions” was taken up exclusively with the specific objectives to characterize nutmeg accessions based on morphological, biochemical and molecular parameters so as to scale the variability in a multidimensional way. Select fifty nutmeg accessions from a core germplasm collected and maintained in a private plantation in the Chalakudy river basin, belonging to age of fifteen years, formed the material for the study. Among the select fifty accessions, forty two were females, four monoecious and four males. In the morphological characterization, 51 qualitative and 38 quantitative characters were recorded from two trees per accession. Biochemical characterization was done in the select seventeen distinct accessions. GC-MS profiling was done in kernel and mace oils. Biochemical constituents of fresh pericarp were estimated. Isozyme profiling was done for peroxidase and polyphenol oxidase enzymes. The molecular characterization was attempted with 21 RAPD and 12 ISSR primers after screening. A key for identification of an elite nutmeg tree was developed. A descriptor for nutmeg with a set of 51 qualitative and 38 quantitative parameters and descriptor states for each of these characters was developed as the first step. This is the first study of its kind to develop a minimal descriptor for nutmeg. The descriptor developed from the present study was simultaneously utilised for morphological characterization and evaluation of the accessions. Wide variability was noticed among the accessions for 47 out of 51 qualitative characters. Four characters viz., leaf margin, fruit pubescence, grooves on nut and nature of fruit dehiscence were noted as non variable characters and hence, these were not included for further analysis. Based on the qualitative characters, accessions were classified into 11 clusters at 66 per cent similarity level. Accessions differed significantly for all the quantitative characters except shelling percentage. Performance evaluation of the accessions brought out the superiority of accession 8, 9 and 22 for yield. The accessions showed high GCV, PCV, h2 and genetic gain for most of the characters. Number of fruits per tree, fruit set percentage, number of fruits per m2, fresh and dry weight of mace, mace volume as well ratio of nut to mace exhibited high genetic gain. Hence, selection programme based on these characters will be very effective in improving the base populations. Based on Mahalanobis D2 analysis, accessions were grouped into 10 clusters. Wide range of variation was observed in contents of volatile oil, oleoresin and fixed oil of kernel and mace. Based on these constituents accessions were grouped into 26 clusters, which indicated their distinct quality. Based on the results of the morphological characterization, seventeen distinct accessions were selected for further biochemical and molecular analysis. GC-MS analysis of kernel and mace oils exhibited 20 and 24 constituents respectively. Volatile oil composition exhibited wide variability for the major constituents viz., myristicin, elemicin, safrole and sabinene apart from the presence of some unique compounds. Grouping of the accessions was done based on the per cent content of these important compounds. Two accessions recorded high contents of both myristicin and elemicin whereas another two accessions were in the complimentary; belonging to low myristicin group. High sabinene combined with low myristicin was the intrinsic quality attribute of one of the accessions. Change, as well as addition/deletion of specific constituents was also noticed in the volatile oils after storage for one year. Accessions exhibited wide range of variation in the biochemical constituents of pericarp, a valuable information for the value addition of pericarp. Total phenol and tannins exhibited high variation. The accessions were ranked based on the content of biochemical constituents. Isozyme profiling using peroxidase enzyme produced four bands and that based on polyphenol oxidase exhibited three bands. Molecular markers could assess the variability among the accessions. The selected 21 RAPD primers produced a total of 164 amplicons of which 63.21 per cent were polymorphic. The 12 ISSR primers selected produced a total of 87 amplicons of which 69.44 per cent were polymorphic. Few unique bands were detected for specific characters. Inter cluster association of each of the qualitative clusters with other clustering patterns was worked out. The results indicated the differences as well as similarities of the qualitative clusters with other clustering patterns. Finally, key quantitative characters were identified based on their direct and indirect effect on yield as also economic importance. The statistical key thus developed using 13 key quantitative characters will serve as a preliminary tool for identification of an elite nutmeg tree.
Open Access
General combining ability of selected black pod disease resistant cocoa(Theobroma cacao L.)hybrids
(Department of Plantation Crops, College of Horticulture, Vellanikkara, 2016) Varsha Babu; KAU; Suma, B
Cocoa originated in the Amazon riverbasin of South America. The cultivation of cocoa had extended from Mexico to Costa Rica and over the time it had spread to Caribbean and other parts of South America (Wood and Lass» 1985). It was introduced to India during 1979. The generic name Theobronia was derived from two greek words 'Theo' means god and 'hroma' means food, hence known as '"food of god". The beans are the only source for chocolate. Cocoa is affected by many biotic and abiotic stresses. Among the biotic stresses Phytophthora pod rot is the most serious one affecting cocoa, leading to a total of 64% yield loss (Adomako, 2007). Therefore the control of black pod is a major challenge for cultivation of cocoa. The farmers adopt several measures to control the disease of which the use of copper based fungicides is the most predominant one (Tan and Tan, 1990). Although it is reasonably effective, their indiscriminate use poses serious environmental issues. To overcome this situation breeding for resistance to black pod is the most economical, environmental friendly and effective control method (Iwaro et al., 2004). Hence an organized breeding progianmiewas initiated at Cocoa Research Center (CRC), KAU, Vellanikkara during 2005 for the development of varieties resistance to black pod disease and high yield. Twenty five hybrids showing considerable level of resistance after 6 years of screening were selected for the present study. The morphological evaluation ot these hybrids were earned out based on eight qualitative and eight quantitative characters.Variability was observed among the hybrids for all the qualitative characters and quantitative characters. Among the hybrids, hybrid H22 recorded the highest pod weight (724g) and total wet bean weight per pod (176.98g). Tlie husk thickness and number of ilat beans were lowest for hybrid H16 (0.86 cm) and HII (1.40). Self incompatibility was assessed by self pollinating 100 flowers per hybrids. Twenty two hybrids turned to be self incompatible, one self compatible and rest with insufficient number of flowers. Out of 22 self incompatible hybrids eleven were selected for further study based on their yield (No. ol pods/ tree/ year). They were crossed with tester (G.I 5.9) in top cross model and only four yielded fruits. Seedlings were raised in the nursery and observations were recorded in the third month. The analysis of variance of top cross showed significant variation for two characters. The characters like height, diameter, chlorophyll and number of leaves did not express any significant difference. HD2is considered as an indicator of initial vigour and it is found to be directly correlated to the final vigour.The significant value for variance (p Vs c) for HD2 indicated substantial difference between the parents as agroup and their hybrid progenies as another group. This shows that the average hetero.sis is significantly high. Seven hybrids out of selected eleven did not yield any pod on cross pollination, progenies developed from open pollinated pods of these hybrid.s were evaluated to predict the performance of the parent. Progenies expressed high HD2 value. Based on this, these parents can be considered as superior ones. However this has to be confirmed further by crossing them with another tester. Nursery screening for Phytophthora resistance of top cross progeny and open pollinated progeny of all eleven selected hybrids were done at two weeks interval for three months. Lab screening for disease resistance was carried out in semi translucent leaves from all the progenies raised through top cross and open pollinated method along with control for eight days by providing artificial inoculation and percentage of infection was calculated. No disease incidence was noticed in any progenies indicating high GCA for this character. H 17 found to be superior combiner can be evaluated in comparative yield trial. H4, HIS and H8 were selected as superior ones based on the performance of open pollinated progeny which has to be further evaluated with another tester.
Open Access
Development of tropical gynoecious lines in cucumber (Cucumis sativus L.)
(Department of Olericulture, College of Horticulture, vellanikkara, 2016) Karthika, A K; KAU; Pradeepkumar, T
The present study ‘Development of tropical gynoecious lines in (Cucumber sativus L.) was carried out at Department of Olericulture, College of Horticulture, Kerala Agricultural university, Vellanikkara, Thrissur during August - November 2014 and February - May 2015 to evaluate the F1 hybrids and their F2 population for identifying stable tropical gynoecious lines of salad cucumber. Twelve hybrids produced by crossing gynoecious line EC 709119 with selected tropical monoecious parents were evaluated for gynoecy under rainshelter. Observations on important quantitative and qualitative characters were recorded. These hybrids were selfed to generate F2 population. F2 population was evaluated for expression of gynoecious character, viz., days taken for female flower anthesis, node at which first female flower emerged and total number of female flowers. The data was subjected to analysis of variance and variability among the genotypes was calculated. Most of the characters exhibited high heritability except for fruit parameters like fruit length, fruit girth and flesh thickness. For gynoecy F2 population from the cross EC 709119 x IC 538186 was observed as the most promising one. This population took only minimum days to form female flower and took minimum number of nodes to form female flower with highest number of female flowers and minimum male flowers. Sex ratio was estimated for parents, F1 hybrids and F2 population. Some of the parents having high sex ratio failed to transmit the same to its hybrid progenies. Among the parents, IC 538186 exhibited highest sex ratio. The highest sex ratio among the F2 population was for EC 709119 x IC 538186. Two populations viz., EC 709119 x IC 527427 and EC 709119 X IC 538186 exhibited a sex ratio of more than 2. The 4 F2 population evaluated for gynoecious trait were classified into monoecious and gynoecious character and tested for goodness of fit based on chi square test with monohybrid ratio of 3:1 being monoecy dominant over gynoecy. Out of the 4 populations, 2 populations were found to express significant value and fit in 3:1 ratio for dominant monoecious trait. The other 2 populations failed to fit in the 3:1 ratio. Bitterness was an important quality character which was absent in most of the parents except three of them during initial harvest. The crosses involving parents prone to bitterness were found to be bitter during later harvest, though all crosses were free of bitterness during initial stage. During later harvests, five parents were found to be bitter. Downy mildew incidence on parents and F1 hybrids were analyzed and Percentage of Disease Intensity (PDI) was estimated. Among parents, IC 538186 exhibited minimum infection and falls under the category of moderate resistance. Hybrid, EC 709119 x IC 538186 exhibited minimum infection and falls under the category of moderate resistance. Among 12 F2 populations, EC 709119 x IC 538186 produced maximum number of true gynoecious plants whereas eight F2 populations failed to produce even one true gynoecious plant. This population also exhibited moderate resistance against downy mildew disease and could be selected for developing true breeding stable gynoecious line for future breeding programme. Present investigation proved the scope of developing tropical gynoecious line from temperate lines by crossing with potential-monoecious lines and making selection in advance segregating generations for gynoecy.
Open Access
Development of bacterial wilt resistant F1 hybrid(s) in chilli (Capsicum annuum L.)
(Department of Olericulture,College of Horticulture, Vellanikkara, 2016) Nimisha, Sara James; KAU; Nirmala, Devi S
A study on the ‘Development of bacterial wilt resistant F₁ hybrid(s) in chilli (Capsicum annuum L.)’ was conducted at the Department of Olericulture, College of Horticulture, Vellanikkara during May 2015 to March 2016. The investigation was done in three experiments with the objective to develop high yielding bacterial wilt resistant F1 hybrids in chilli and to estimate combining ability and heterosis for yield and yield components.
Open Access
Development of aloe vera gel supplemented ready to serve fruit beverages
(Department of Processing Technology, College of Agriculture, Vellayani, 2016) Shymi, Cherian; KAU; Geetha, Lekshmi P R
The present study entitled “Development of Aloe vera gel supplemented Ready To Serve fruit beverages” was carried out in the Department of Processing Technology, College of Agriculture, Vellayani during 2014-2016 with the objective to optimize the process variables for osmotic dehydration of aloe gel, supplementation of aloe gel in Ready To Serve (RTS) fruit beverages and to evaluate the quality of the product during storage.
Open Access
Shrink wrap packaging of selected tropical fruits
(Department of Processing Technology, College of Horticulture, Vellanikkara, 2016) Aiswarya, T; KAU; Saji, Gomez
The present study titled “Shrink wrap packaging of selected tropical fruits” was carried out in the Department of Processing Technology, College of Horticulture, Vellanikkara during 2015-2016. The objective was to extend shelf life and to maintain quality of mango, banana and pineapple during storage. The technique of shrink wrap packaging was adopted in three tropical fruits viz., mango, banana and pineapple. Each experiment consisted of 7 treatments wherein shrink wrap packaged fruits along with the unwrapped (control) samples were stored under ambient conditions. Observations on shelf life and PLW (physiological loss in weight) were recorded at an interval of three days and the biochemical characteristics were analysed at weekly intervals.Mature fruits of mango variety Prior, free of damage and bruises, were washed in plain tap water followed by surface sanitization with 100ppm chlorine for 15 minutes. The chlorinated fruits were spread out on blotting paper to remove excess surface moisture. Surface dried fruits were subjected to two forms of shrink wrapping i.e, individual fruit wrap and wrapping of 4-5 fruits in areca plates with polyolefin film of three densities viz., 15, 19 and 25 μ. Individually shrink wrapped mangoes in 25 μ polyolefin film had the longest shelf life (18 days) and the shrink wrapped fruits
Open Access
Standardization of hydroponics in tomato
(Department of Olericulture, College of horticulture, Vellanikkara, 2016) Reshma, T; KAU; Salikutty, Joseph
The present study on “Standardization of hydroponics in tomato” was carried out in the Department of Olericulture, College of Horticulture, Vellanikkara, during 2015 September to 2016 January, to standardize the nutrients, methods and growing media for the hydroponic cultivation of tomato in rain shelter. The experiment was laid out in CRD with a total of 13 treatments comprising of two hydroponic methods: a) Deep Flow Technique, b) Ebb and Flow Technique; two nutrient solutions: a) Cooper’s solution, b) Hoagland’s solution and three growing media: a) coco peat, b) expanded clay pellets, c) pebbles and a control where the plants were grown in soil with POP recommendations. Plants in soil with POP recommendations showed superiority for plant height, days to first flower appearance, days to first fruit set, days to first harvest, fruits per plant, duration of the crop, number of harvests, yield per plant, and average fruit weight over the hydroponic treatments. The NPK content in plant parts were higher for plants grown in soil. The benefit cost ratio was also the highest (1.92) in control treatment. Among the hydroponic treatments, F2S1M1, (a combination of Ebb and Flow Technique, Cooper’s solution and coco peat) was the best with respect to growth, yield per plant (1.67 kg) and benefit cost ratio (1.33). There was only a reduction of 19.71 per cent in yield for this treatment when compared to plants grown in soil. Under Deep Flow Technique in a unit area of 1m², 14 plants were accommodated, whereas in control there were only 9 plants. When yield per unit area was considered, F1S1M1 (a combination of Deep Flow Technique, Cooper’s solution and coco peat) was the best (18.48 kg), and this was on par with the plants grown in soil (18.72kg). The quality parameters (TSS and acidity) were influenced by the hydroponic methods. The TSS of fruit was higher and acidity was lower under hydroponics compared to soil. The influence of nutrient solutions on the growth and yield parameters of tomato plants were significant. Out of the two nutrient solutions tested, Cooper’s solution was significantly better. The growth and yield parameters were significantly influenced by the growing media and were the best in coco peat medium, followed by pebbles. This may be because of the high nutrient content in coco peat (N- 0.32%, P- 0.01%, K- 0.36 %). In expanded clay pellets, plants were less vigorous. Diseases were totally absent and only stray incidence of insect pests like serpentine leaf miners, mealy bugs and plant hoppers were noticed during the course of the experiment. Biocontrol measures were employed as and when the incidence was observed. Though limitations have been experienced as the first experiment of its kind, hydroponics can be practiced in Kerala by adopting cost effective and locally available growing media, since there is space constraint for conventional cultivation

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