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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
Evaluation of ornamental flowering shrubes for tropical landscapes
(Department of Pomology and Floriculture, Colege of Horticulture, Vellanikkara, 2012) Najeeb, Naduthodi; KAU; Valsalakumari, P.K.
The present study entitled “Evaluation of ornamental flowering shrubs for tropical landscapes” was carried out at the Department of Pomology and Floriculture, College of Horticulture, Vellanikkara from Jan. 2011 to Dec. 2011. The objectives were to evaluate ornamental flowering shrubs for suitability to various landscaping uses and to compute Air Pollution Tolerance Index. The study involved evaluation of 30 tropical ornamental flowering shrub species or varieties. The selected shrubs were four years old, maintained in the shrubbery of the Department of Pomology and Floriculture. The experiment was laid out in CRD with three replications. Various vegetative and floral characters were recorded and data analysed and correlation studies were made with weather parameters. Shrubs selected for the study were described based on morphological characters. Growth of shrubs was measured in terms of height and spread. Based on the manageable height, they were classified into three groups, i.e. Tall (height above 2 m), Medium (height 1m- 2m) and Dwarf (height below 1m). Among the 30 shrubs evaluated, the maximum height was observed for Calliandra haematocephala (319.4 cm) and the minimum for Lonicera japonica (49.9 cm). Plant spread varied from 43.4 cm in Wrightia antidysenterica to 269.7 cm in Calliandra haematocephala. Regression equation of height for predicting spread was formulated using the monthly data on height and spread. Foliage characters like leaf length, leaf area, petiole length, girth and internodal length were measured. Based on leaf area, plants were categorized into medium coarse, medium, medium fine and fine textured. Qualitative characters of the foliage like shape of leaf, base, tip, margin and colour of leaf were observed and used for plant description as well as categorizing them into different texture classes. Shrub canopy shape (silhouette) was observed and used for making schematic diagram. Qualitative characters of flowers like type of inflorescence, position of inflorescence, colour and fragrance were observed. Time taken to open up the inflorescence from bud stage, persistence of single flower as well as the inflorescence were also observed. Quantitative characters like inflorescence diameter, single flower length and diameter and number of flowers per inflorescence were also recorded. Flowering seasons of the shrubs were observed and accordingly they were categorized into four different phenological phases i.e. Dec-Feb, Mar-May, June- Aug and Sep-Nov. Sideruns were observed and phenological configurations were made. Air Pollution Tolerance Indices of the shrubs were calculated. Calliandra haematocephala (31.7) showed the highest APTI value and the minimum value was observed for Allamanda cathartica ‘Dwarf’ (9.2). Shrubs were categorized into sensitive (value ≤14), intermediate (15- 19), medium tolerant (20-24) and tolerant (> 24) groups based on their APTI values. Based on the different characters studied, shrubs were classified into different landscape utility groups such as, accent plant, foundation planting, screening and privacy, hedges and topiary, shrub border, background planting, corner planting, Shrub group and mass planting, Pot and Container planting, fragrant garden, moon garden, xeriscaping, rock garden, covering sloppy banks and butterfly garden. Shrubs were observed for pest and disease incidence. Major pests were leaf eating caterpillars in Mussaenda erythropylla, Nerium indicum, Calliandra haematocephala and Ixora coccinea, flower bud borer in Wrightia antidysenterica, mealy bug and scales. Shrubs were not severely affected by diseases. Minor leaf spots were observed in certain shrubs. In the present study, shrubs were recommended for various functional uses in the landscapes based on their growth, flowering and morphological characters. Based on flowering season, they were categorized into four phenological phases. Side-runs were observed and phenological configurations were made. Air Pollution Tolerance Indices of the shrubs were also computed and the plants were categorized according to their APTI values.
Open Access
Biodiversity analysis of traditional mango types of Kerala and studies on the reproductive biology of selected popular types
(Department of pomology and floriculture, College of Horticulture, Vellanikkara, 2011) Mannambeth Renisha, Jayarajan; KAU; Parmeswaran, N K
The present investigations entitled “Biodiversity analysis of traditional mango types of Kerala and studies on the reproductive biology of selected popular types” were undertaken at the Department of Pomology and Floriculture, College of Horticulture, Kerala Agricultural University, Vellanikkara, Thrissur during 2009-2011. Major objectives of the study were to assess the biodiversity status of traditional mango types in selected villages of Thrissur and Palakkad districts of Kerala by applying participatory tools and studying the floral biology, pollen characters, pollination and self and cross compatibility factors in six mango varieties commonly grown in the homesteads of Kerala. These studies formed a part of the departmental project entitled “Hybridization of mango varieties of Kerala” and were taken up under two broad components during implementation. Component I: Primary assessment of indigenous mango types was initiated by surveying homesteads in Vallachira and Pazhayannur GP‟s of Thrissur district and Kollemgode and Muthalamada GP‟S of Palakkad district. Homesteads were selected by snowball sampling. Dominant local types in these homesteads were Muvandan in Pazhayannur and Chandrakkaran in Vallachira GP of Thrissur whereas Muvandan, Priyur, Chandrakaran and some unnamed landraces in Kollemgode and Muthalamada GPs of Palakkad district. Final village level biodiversity assessment was done in Maruthampadam in Pazhayannur GP (Thrissur Dt) and Erippadam in Muthalamada GP (Palakkad Dt.). Farmer participatory 4- cell analysis (FCA) and focus group discussions (FGD) were made by organizing farmers interface in these villages. Data recorded showed that Maruthampadam village was richer in crop diversity than Erippadam. Based on the FCA, Muvandan, Pulimanga and Gomanga could be grouped as the „common‟ types of the Maruthampadam village while the „rare‟ types included Karpuramanga, Ganapatimookan, Kilichundan, Chandrakaran, Kottamavu, Sindhuram, Marathakam and Mundappa . „Common‟ mango types in Erippadam village were Alphonso, Banganapalli, Kilichundan, Neelum, Sindhuram, Muvandan, Nadasala and the „rare‟ types being Chandrakaran, Kilimook, Mallika and Mundappa. The varietal richness of Erippadam was higher than Maruthampadam village. In Maruthampadam village, recorded evenness value was highest for Muvandan while it was zero for the „rare‟ and „vulnerable‟ types. In Eripaddam, „common‟ types registered higher evenness values than „rare‟ types. Varietal richness as related to size of gardens indicated positive relationship in Erippadam village. ITK documentation from the villages provided some useful information on the traditional processing and product diversification of mango fruits practiced by the villagers in Maruthampadam. Component II: The varieties involved in the study were Muvandan, Neelum, Priyur, Vellaikolumban, Banganapalli and Alphonso. Mango flowering in both the seasons during 2009-10 and 2010-11 were of much erratic, poor and belated nature. A definite influence of the shift in north east monsoon pattern experienced during these periods could be attributed as the major contributory factor to the above. Peak anthesis was noted between 7.30 and 11.00am in all varieties and anther dehiscence between 8.30 am and 12 noon. Highest stigma receptivity was on the day of anthesis. Panicles of Muvandan and Priyur were longer than the other varieties. The varieties Neelum, Priyur, Alphonso, Vellaikolumban, and Muvandan exhibited a mixed phase while opening out but in Banganapalli, flower opening started with a pure male phase and thereafter entered mixed phase. Inflorescence rachis of Muvandan was dark red in colour where as in Neelum and Alphonso it was light red. Light green coloured inflorescence rachis was observed in Banganapalli and Vellaikolumban while in Priyur it was light green with reddish tinge. Size of inflorescence was highest in Muvandan while it was lowest in Neelum. Intensity of flowering per unit area of tree canopy was highest in Alphonso where as it was lowest in Vellaikolumban. Highest percentage of hermaphrodite flowers was recorded in Vellaikolumban (46.38%) while it was lowest in Banganapalli (0.02 %). The varieties Neelum, Priyur, Alphonso and Vellaikolumban showed round shaped pollen whereas oval and oblong shaped pollen was noted in Banganapalli and Muvandan, respectively. The size of the pollen ranged in between 27.29μm and 33.34μm. Pollen production and viabiliy were related to climatic variations. Pollen storage in refrigerated conditions retained viability for 72 hours. Selfing did not result in fruit setting and apparently indicating the involvement of incompatibility factors. It has to be further confirmed by flourimetric methods. Crossing among the varieties affected fruit setting obviating the involvement of incompatibility factors. Four successful hybrid mango progeny seedlings are available finally for performance evaluation.
Open Access
Evaluation of round fruited brinjal genotypes for yield, quality and tolerance to fruit and shoot borer.
(Department of Olericulture, College of Agriculture, Vellayani, 2011) Kranthi Rekha, Gogula; KAU; Celine, V A
The present investigation on “Evaluation of round fruited brinjal genotypes for yield, quality and tolerance to fruit and shoot borer” was conducted at the Department of Olericulture, College of Agriculture, Vellayani, during the period 2010-2011. The objective of the study was to assess the genetic variability for yield, quality and resistance to fruit and shoot borer and elucidating the morphological, anatomical and biochemical basis of fruit and shoot borer resistance. The study was conducted in two separate experiments. 1. Screening brinjal genotypes for yield and fruit and shoot borer resistance 2. Evaluation of genotypes for genetic variability, yield, quality and tolerance to pests and diseases. In experiment I, thirty four accessions of brinjal were collected from different parts of country and grown in the field in RBD with three replications. Analysis of variance revealed that significant difference among the accessions for all the characters studied. SM 49 and SM 36 showed lowest infestation to fruit and shoot borer while SM 23 showed highest. Among other pests, SM 36 and SM 40 had severe incidence of jassids and ash weevils respectively. In experiment II, the yield ranged from 3.62 kg to 0.66 kg. SM 49 was superior for plant height, percentage of long and medium styled flowers and yield. Highest fruit weight was in SM 44. High phenotypic coefficient of variation and genotypic coefficient of variation were observed for yield per plant, fruits per plant, fruit weight and branches per plant. High heritability and high genetic advance also observed for these characters. At genotypic level, yield per plant had high positive correlation with percentage of long and medium styled flowers, branches per plant, fruit length and plant height. The path analysis showed that percentage of long and medium styled flowers, branches per plant, fruit length and fruits per plant had direct effect on yield per plant. SM 49 followed by SM 44, SM 23, SM 41 and SM 30 was having the highest selection index values based on discriminant function analysis. Based on Mahalanobis D2 analysis the current genotypes were grouped into five clusters. Cluster I being the largest including with twenty accessions and cluster II and V had one each. Cluster V had highest values for seven characters viz., plant height, secondary branches, percentage of long and medium styled flowers, fruit length, fruits per plant and yield per plant. Highest inter cluster distance was between cluster II and V. Maximum intra cluster distance was in cluster IV. In screening for fruit and shoot borer resistance, the incidence ranged from 4.77 to 31.97 per cent and 10.83 to 63.01 per cent for shoot and fruit respectively. However accessions viz., SM49 and two local collections SM 44 and SM 36 showed moderate resistance to fruit and shoot borer. Fruit colour was related to fruit and shoot borer tolerance. Light coloured fruits were less susceptible. More RLPS and less RLSA led to tolerance. In moderately resistant accessions there was more number and well developed vascular bundles compare to susceptible ones. High phenol and proline content and less sugars and protein content were responsible for resistance to fruit and shoot borer incidence. Accession like SM 23, SM 36, SM 40, SM 44, SM 45 and SM 49 showed high level of resistance to bacterial wilt. The accessions SM 36, SM 44, SM 45 and SM 49 showed resistance to both fruit and shoot borer and bacterial wilt. The study identified the high yielding, large fruited SM 44 with resistance to fruit and shoot borer and bacterial wilt as a promising line for cultivation in Kerala after further confirmatory studies.
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
Optimization of process variables for osmo-air dehydrated nendran banana (Musa spp.)
(Department of Procesing Technology, College of Horticulture, Vellayani, 2015) Keerthishree, M; KAU; Geetha Lekshmi, P R
The study entitled “Optimization of process variables for osmo-air dehydrated Nendran banana (Musa spp.)’’ was conducted at Department of Processing Technology, College of Agriculture, Vellayani, during 2013-15 with the objective to standardize different process variables like fruit slice shape and thickness, osmotic solution concentration and immersion time for osmo-air dehydration of Nendran banana and to optimise the conditions suitable for better mass transfer kinetics. Optimally ripened nendran banana (cv. Kaliethan) sliced into three shapes viz. long (5cm), round and ring of thickness 5, 10 and 15 mm each were osmosed in sugar syrup of 50, 60 and 70⁰ B concentration with an immersion time of 40, 60 and 80 minutes. Osmosed fruit slices were dried in cabinet drier at 50⁰ C till it attained moisture content of 171 % and analysed for physical, nutritional and sensory qualities. Observations on mass transfer, physical and nutritional parameters were statistically analysed using Response Surface Methodology (RSM) and response surfaces were fitted using SAS software (ver 9.3). Mass transfer characters viz., solid gain, water loss, weight reduction and ratio of water loss to solid gain increased with increase in concentration of osmotic solution, thickness of slices and duration of immersion time irrespective of fruit shapes. Nutritional parameters of osmosed nendran banana exhibited an increase in total soluble solids, reducing sugars, total sugars with increase in thickness, concentration and time of immersion and a decreasing trend in acidity and vitamin C in all the three shapes. During drying water loss, weight reduction, drying rate and rehydration ratio decreased with increase in thickness and it increased with concentration and time of immersion. Shrinkage (%), browning index and textural qualities like cutting force and cutting energy also increased. Quadratic regression equation models were developed for all the responses with R2 > 90 %. Predictive model for water loss of longitudinally sliced nendran banana is WL= -7.01+8.77X1+6.52X2+3.57X3-0.91X11-0.89X22-0.036X33+0.20X1X2+0.29X1X3-0.68X2X3 where X1 is thickness, X2: concentration and X3: time of immersion and coded as X1=thickness/5, X2= (concentration-40)/10, X3=(Time-20)/20. Estimated minimum water loss for osmosed longitudinal slices was 15.14 % at thickness 5.54 mm, concentration 56.94 ⁰B , immersion time 53.26 minutes whereas estimated maximum water loss of 29.38 % was obtained for slices with thickness 14.09 mm, concentration 62.38 ⁰B and immersion time 70.41 minutes. Based on sensory analysis, ten best treatments were selected and stored at room temperature for six months after packaging in 200 gauge polypropylene and analysed at monthly interval for nutritional, physical and sensory qualities. During storage, increase in moisture content (17.51 to 24.61 %), reducing sugar (44.95 to 51.19 %) and browning index (148.29 to 165.60) were observed where as acidity (1.71 to 1.12 %), total sugars (55.91 to 50.65%), vitamin C (27.85 to 27.73 mg/100 g) and rehydration ratio (1.82 to 1.35%) decreased. Textural qualities viz. cutting force and cutting energy increased from 34.73 to 41.76 N and 31.80 to 39.13 Ns respectively during storage. Sensory qualities of the product decreased slightly towards the end of storage and no microbial growth was found till the end of storage. Second order response surface models were developed for mass transfer, drying and nutritional parameters of osmo-air dehydrated nendran banana. Slices of 5 to 10 mm thickness, 50 to 60⁰ B concentration and 50 to 60 minutes of immersion time were the optimized parameters for longitudinal and round slices whereas it was 5 to 8 mm, 50 to 55⁰ B and 40 to 50 minutes for ring shaped slices. Five and 10 mm thick rings of ripe nendran banana followed by 5 mm round slices osmosed in 50 ⁰B sugar syrup for 40 minutes were highly acceptable for developing good quality osmo dehydrated products. The products packaged in 200 gauge polypropylene were acceptable and microbiologically safe up to six months when stored at room temperature.
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.

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