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ThesisItem Open Access Evaluation of nendran (musa aab group) ecotypem(Department of Horticulture, College of Agriculture, Vellayani, 1996) Bindu Viveka, Devi; KAU; Jayachandran Nair, C SThe investigation "Evaluation of 'Nendran' (Musa AAB group) ecotypes" was conducted at the Department of Horticulture, College of Agriculture, V e l l a y a n i , Thiruvananthapuram during 1994-'95 inorder to study the effect of ecotype variation on growth, yield and fruit quality of 'Nendran' banana. The results obtained are presented below : Vegetative characters like plant height, girth at later stages, number of leaves per plant, phylacron at early stages, leaf longevity, leaf area duration, leaf area index at later stages and monthly growth rate at early stages showed variation among the different ecotypes. The number of suckers per plant were almost uniform for all the ecotypes. The time taken for flowering and total crop duration varied with ecotypes but the maturity period of the bunches was uniform for all the ecotypes. Eventhough bunch yield was maximum in Kaliethan, the number of hands and fingers per bunch were the lowest in this type. Fruit characters like finger length, finger weight, peel weight and pulp weight were high in Kaliethan where as the pulp/peel ratio was high in Poovanchira. Chengazhikodan and Kothala were superior in fruit quality compared to Kaliethan. The leaf nutrient status at flowering stage varied only in the case of potassium where as both phosphorus and potassium varied at harvest stage. Poovanchira, Puthur and Kothala types had higher levels of NPK at flowering time though Chengazhikodan had the highest potassium content. During harvest stage, Kothala and Chengazhikodan had higher NPK content compared to others types. The dry matter production was higher in Kaliethan and Pandaloor in both vegetative part and fruits. The extent of sigatoka leaf spot did not differ significantly among the 'Nendran' ecotypes during the different stages of growth. There was no incidence of bunchy top in any of the treatment plants. Nematode infestation in root was low in Poovanchira, Kaliethan and Chengazhikodan and high in Muttathukonam and Kothala types where as the rhizome weevil incidence was low in Puthur, Kothala and Kaliethan an 1 high in Chengazhikodan and Pandaloor types. Correlation and path analysis studies in 'Nendran' ecotypes indicated that leaf area duration (LAD), girth • fingers, time taken for flowering, number of fingers re bunch, plant height at post floral initiation stage and g i r t h of plant at floral initiation stage had a p o s i t i v correlation with bunch weight. So these characters can 1 -? considered for selecting superior ecotypes. In general, Kaliethan can be considered as the most suitable ecotype of 'Nendran' for commercial cultivation in Thiruvananthapuram and nearby areas. However, the o'h'i types such as Kothala, Chengazhikodan and Poovanchira typos can also perform well in this tract once they become adapt '1’ to the agroclimatic conditions of the zone.ThesisItem Open Access Standardisation of in vitro techniques for rapid multiplication of holostemma annulare k schum(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1996) Sophia John, A; KAU; Kesavachandran, RStudies were conducted on standardization of in vitro techniques for the rapid multiplication of Holostemma annulare K. Schum. At the Plant Tissue Culture Laboratory of the Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara during 1993-1995. Surface sterilization was standardized for explants from different sources. For two to three month old explants from the glasshouse, treatment with 0.1 per cent mercuric chloride for 5 min or 10 min was found to be better. A combination of sterilants was necessary for mature explants taken either from the glasshouse or field. Explants collected in the months of January and February gave the lowest contamination rate. Early release of buds and further growth of nodal segments and shoot tip explants was better in MS media supplemented with BA. Cultures in medium containing KIN were short, robust, darker and with lesser number of buds and shoots than those in medium containing BA. Extremely low concentrations of TDZ could stimulate axillary bud proliferation. Additives like silver nitrate and activated charcoal could drastically reduce callus production in culture, but the shoot growth was also reduced with these additives. Nodal segments were better in respect of early release of buds, more number of longer shoots, nodes and buds than shoot tips. Higher temperature proved better than lower temperature for the growth of cultures. Also exposure to light was favourable for healthy growth of shoots. Proliferation rate was higher at higher concentrations of BA but the shoots were very swollen, weak and had to be subcultured as a clump into media containing lower concentrations of BA for healthy growth of shoots. Shoots could be proliferated at extremely low concentrations of TDZ. MS basal with full concentration of salts was better for better growth of shoots. When the best treatment in each subculture was given in sequence approximately 2 crores 37 lakh nodes could potentially be obtained over a period of 225 days. Maximum rooting, early rooting and more number of longer roots could be obtained in solid. MS basal media when shoots were kept for in vitro rooting. Ex vitro rooting of shoots was successful when they were treated with IBA 1000 mg1-1 as quick dip followed by planting in plastic pots filled with sand in the initial stages for early rooting and then transplanted to plastic or mud pots filled with cocofibe for vigorous growth of root and shoot portions. TDZ produced the highest callus index at relatively lower concentrations. The callus produced was hard, green in colour and compact. 2, 4-D proved better than NAA for obtaining more regenerative callus among the auxins tried. Leaf segments (with or without petiole attached) oriented with the abaxial surface touching the solid medium supplemented with 2,4-D and exposed to light alone produced embryoids after one or two subcultures into MS medium with lower concentrations of 2,4-D. The embryoid production could be triggered if the calli were subcultured to liquid MS basal medium and when further transferred to solid media alone produced elongation of such embryoids. But the original explants had to be raised in MS medium supplemented with either TDZ or KIN as cytokinin for the embryoids to form subsequently. Encapsulated beads were successfully formed with nodal segments using 2.5 per cent sodium alginate and 75 mM calcium chloride with a complexation time of 30 min and the beads could be stored successfully for 15 days at room temperature and upto 40 days at 40 C. The peroxidase isozyme pattern of the leaves and roots from in vitro plantlets and in vivo plantlets were similar having the same number of bandsThesisItem Open Access Standardisation of propagation techniques in schefflera(Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, 1997) Sunitha Anne, Mathew; KAU; Murali, T PThe study was carried out at the Department of Pomology and Floriculture, Vellanikkara and Agricultural Research Station, Mannuthy from March 1994 to February 1996 to standardise the propagation techniques in schefflera arboricola). Schefflera, a member of the botanical family, Araliaceae is valued for its ornamental foliage. Not much information is available in the literature on agro techniques for the commercialization of this important foliage plant. Hence, the present study “Standardisation of propagation techniques in schefflera” has great relevance. In both ‘green’ and ‘variegated’ type of schefflera, double noded cuttings performed better than single noded cuttings. The number and quality of roots produced were improved with growth regulator treatments and the prolonged dip method was found to be the best in both ‘green’ and ‘variegated’ type of schefflera. The best growth regulator and its optimum concentration for rooting of cuttings in ‘variegated’ type was IBA at 200 mg 1-1 whereas in ‘green’ type, NAA at 50 mg 1-1 was found to be an effective treatment. Percentage success in rooting of cuttings depended on the growth regulator employed. In ‘variegated’ type of schefflera the percentage success obtained in rooting of double noded and single noded cuttings could be improved with IBA treatment and in ‘green’ type, NAA treatment was found to be beneficial. In layering also growth regulator treatment was found to be beneficial. In ‘variegated’ type NAA at 50 mg 1-1 produced maximum rooting whereas in ‘green’ type NAA at 200 mg 1-1 produced longer and stouter roots. The media used and the method of wounding adopted in layering were found to have significant influence on rooting behaviour. Girdling was found to be more effective compared to slanting slit method. The best media were sphagnum moss and sawdust in ‘variegated’ type whereas in ‘green’ type, sawdust was the best medium. Percentage success in rooting of layers depended on the growth regulator, media and type of wounding method employed. The percentage success obtained in rooting of layers (‘variegated’ and ‘green’) could be improved with an NAA treatment, using sawdust as the medium and girdling as the wounding method. A comparison of the methods of propagation revealed that in schefflera cuttings could be adopted as reliable and successful propagation method to produce large number of plants in a short time from limited amount of planting materials. In micropropagation, callus was formed from immature and young leaves and the callus production was good with 2, 4-D at 1-2 mg 1-1 and NAA at 10-12 mg 1-1 but the calli did not respond to caulogenesis. In direct organogenesis, axillary bud break from nodal explants was noticed in MS medium with BAP at 0.5 mg 1-1 and the shoot growth was the best with BAP at 5 mg 1-1. The in vitro developed shoots were rooted in the medium supplemented with NAA at 3 mg 1-1 IBA at 0.3 mg 1-1. Further studies are needed to standardise a complete protocol for micropropagation of S. arboricola.ThesisItem Open Access Environmental effects on the growth of philodendron wendlandii(Department of Pomology & Floriculture, College of Horticulture, Vellanikkara, 1996) Swapna, S; KAU; Geetha, C KAn experiment was carried out at the Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, to evaluate the environmental influence on the growth of Philodendron 'Wendlandii'. The effects of media, containers and fertilizer forms and doses were assessed at three levels of shade, namely, 25, 50 and 75 per cent. Results revealed that treatments could significantly influence all the vegetative parameters, viz., plant height, number of leaves, total leaf area and number of side shoots, at different stages of growth. The superiority of the combination of peat, mud pot and soluble fertilizer at its higher concentration was clearly evident with respect to plant height at 25 and 50 per cent shade levels. Controlled release fertilizer substituted in the above combination recorded plant height on par with this, at 25 and 50 per cent shade levels whereas the height was significantly superior at 75 per cent shade level. Number of leaves was higher in the case of peat + mud pot + controlled release fertilizer under all the three shade levels. The above treatment combination produced more leaf area under 50 per cent shade. This was comparable with that of the leaf area produced when soluble fertilizer was used at 75 per cent shade. Number of side shoots was also higher in a combination of peat + mud pot + controlled release fertilizer. Total biomass was a good indicator of the superiority of peat + mud pot -\- controlled release fertilizer at 25 and 50 per cent shade levels. The response in uptake was more in the case of peat supplied with controlled release fertilizer. Better plant quality was observed when grown in peat and mud pot. The shade level of 50 per cent was considerably better with respect to all the growth parameters, such as, height, number of leaves and total leaf area. Although chlorophyll content was maximum under 75 per cent shade, it was on par with that at 50 per cent shade. Overall plant quality too showed superiority of 50 per cent shade level.ThesisItem Open Access Cyto-morphological investigations in piper spp.(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1997) Ambili, Anand; KAU; Sujatha, V SThe study 'Cyto-morphological investigations in Piper spp.' was conducted in the Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara during the period from October 1994 to December 1996. The major objectives were to prepare morphological descriptors for the eight Piper spp. collected from different geographical areas and to conduct cytological investigations in these species. To prepare morphological descriptors for the eight species studied detailed morphological observations were recorded. Based on the salient observations on morphology brief descriptions of the eight Piper spp. were made. The eight species of Piper studied were analysed for the similarities and differences in their morphological characters to find out the relationship among the species. Based on morphological comparisons, a key for identification of species has been proposed. The procedure for mitotic studies in Piper spp. was standardised. The roots were collected between 11.15 a.m. and 12.15 p.m. and pre-treated in 8- hydroxyquinoline for two to three hours at 40 C. The pre-treated roots were fixed in Carnoy's A or Carnoy's B for one or two days. The material was then hydrolysed in 1 N hydrochloric acid in a water bath maintained at a temperature of 600C for fifteen minutes. The roots were then stained in 0.5% acetoorcein for 45 minutes. After that slide preparations were made and examined for the presence of mitotic chromosomes. Microphotographs were taken and good slides were made permanent. Chromosome number of 32, 52, 32, 32, 24, 26, 32, 52 and 52 were observed in P. argyrophyllum, P. attenuatum, P. bababudani, P. betle, P. chaba, P. colubrinum, P. longum, P. nigrum (Panniyur-I) and P. nigrum (wild) respectively: Except for the South American species, P. colubrinum, all the species studied possessed chromosomes in multiples of four suggesting a basic number of four for the Indian Piper.ThesisItem Open Access Harvest and postharvest losses in mango (mangifera indica L.) and its management(Department of Processing Technology, College of Horticulture, Vellanikkara, 1996) Elsamma, Alex; KAU; Narayanankutty, M CThe present investigations on Harvest and postharvest losses in mango (Mangifera indica L.) and its management were conducted in the Department of Processing Technology, College of Horticulture, Vellanikkara, Thrissur, Kerala. Five mango varieties, viz; Prior, Neelum, Bangalora, Olour and Muvandan were used for the study. Harvested fruits having a specific gravity between 1.00 and 1.05 were used. The fruit weight ranged from 177 g (Muvandan) to 439 g (Bangalora). The fruit length and circumference was maximum for Bangalora).(13.3 cm and 26 cm respectively). Shape index was maximum for Bangalora (2.11) while it was minimum in Muvandan (1.16). Neelum had the thickest skin (0.94 mm). Bangalora had the thinnest skin (0.34 mm). Flesh firmness ranged from 0.58 kg/cm2 in Bangalora to 0.73 kg/cm2 in Neelum at the ripe stage. Total sugar content varied between 14.4 per cent (Neelum) and 9.5 per cent (Muvandan and Bangaloa). Neelum recorded highest reducing and non- reducing sugar content (3.3% and 11.1 % respectively). Total soluble solids ranged between 19 degree brix in Neelum and 13 degree brix in Muvandan. Acidity was the highest in Muvandan (0.24 %) and the lowest in Prior (0.11% ). Among different mango harvesters designed and fabricated, KAU mango harvester III was found superior to the traditional harvester, in terms of harvesting efficiency, retention of pedicel and collection of fruits in the net. The extent of spoilage of fruits was less when this harvester was used. The recovery of marketable fruits ranged from 68.0 per cent in Bangalora to 75.75 per cent in Neelum. Padding given for collection baskets did not influence postharvest characters. Among the different types of containers used, packing density was maximum when cardboard box was used, followed by rectangular plastic crate. Studies on the effect of containers and transportation on postharvest losses of mango showed that handling of mangoes in rectangular plastic crate was superior in terms of number of marketable fruits (89.0 %), minimum physiological loss in weight (8.6 %) and less disease incidence (3.0 %). Among various postharvest treatments, dipping of fruits in warm water (520C) containing carbendazim 0.05 per cent showed minimum PLW., less spoilage in terms of shrinkage, discolouration and disease incidence. Important casual organisms identified were colletotrichum gloeosporioides, Aspergillus niger, Aspergillus flavus, Aspergillus aculeatus, Botryodiplodia theobromae, Rhizopus sp and Penicillium sp. Postharvest treatments did not show any effect on spoilage due to fruitflies. Rate of ripening was faster when warm water treatments were used. Warm water treatments gave a better colour for the fruit. Treatment with Carbendazim left high levels of residues in the fruit pulp.ThesisItem Open Access Standardisation of seed processing techniques in chilli (Capsicum annuumL.)(Department of Olericulture, College of Horticulture, Vellanikkara, 1998) Liji, P V; KAU; Meagle Joseph, PStudies on seed quality aspects of chilli var. Jwalasakhi and Ujwala were undertaken in the Department of Olericulture, College of Horticulture, Vellanikkara during 1997-98 to fix the optimum fruit maturity stage and to standardise the best seed processing and storage methods for maintaining viability and getting maximum seed quality. Physiological maturity studies in variety Jwalasakhi indicated that fruits reached maximum size by 30 d.a.a. The fresh weight of fruits was maximum at 35 d.a.a. and it was on par with the fresh weight fruits at 30 and 40 d.a.a. So, vegetable harvest of this fruits can be extended from 30 to 40 d.a.a. In the case of variety Ujwala, both fruit length and fresh weight of fruits was maximum at 40 d.a.a. seeds of 45 days maturity recorded the highest 1000 seed weight in variety Jwalasakhi and it was at 40 d.a.a. in variety Ujwala. Seed germination studies revealed that seeds of 45 day maturity recorded the highest germination percentage. After six months storage seeds of 45 days maturity recorded the maximum germination percentage. In general, speed of germination, vigour index and seedling dry weight were maximum for seeds of 45-50 days maturity and it is the optimum stage for harvesting fruits for seed extraction. Seed quality was found to be influenced by different combinations of seed extraction and fruit drying methods. Sundrying of fruits avoiding the peak hours and hand extraction of seeds retained high viability and vigour of seeds during storage. Fruit drying in mechanical drier was deleterious to the seed quality. Both machine and hand extracted seeds of fruits-dried in mechanical drier recorded the lowest mean germination percentage, speed of germination, vigour and seedling dry weight. High value for electrical conductivity of seed leachate was recorded for the seeds from fruits dried using mechanical drier. The results of the seed storage studies indicated that seed germ inability of both varieties was greater in seeds stored in paper bags and this might be due to the escape of excess moisture released in seeds, during storage. Seed viability and storability are largely dependent on the storage conditions and the air conditioned storage of seeds recorded at the maximum germination percentage, speed of germination, seedling dry weight in both chilli varieties and it was lowest for the seeds stored under ambient conditions. From this study it can be concluded that physiological maturity of seeds in chilli var. Jwalasakhi and Ujwala is attained at 45-50 d.a.a. Hand extraction of seeds and sundrying of well ripe fruits avoiding the peak hours maintained germination and seedling vigour during storage. Air conditioned storage and paper containers were best for maintaining the seed quality upto six months.ThesisItem Open Access In vitro response and cause of recalcitarancy in coconut(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1997) Chandralekha, K; KAU; Rajendran, P CA study was undertaken in the Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, during 1995 to 1997 to find out the in vitro response and causes of recalcitrancy in coconut (Cocos nucifera L.). Young palms of 0 x T parentage were used as source of explants in the present study. Direct and indirect organogenesis and embryogenesis were tried in various explants like zygotic embryo, immature inflorescence rachillae, anther and tender leaves. Coconut tissues usually turn brown under in vitro condition due to polyphenol interference. Addition of 0.25 per cent activated charcoal reduced the phenolic exudation effectively and was found superior to the addition of ascorbic acid or polyvinyl pyrrolidone. The phenolic exudation was considerably reduced under dark condition. Y 3 medium was found to be superior for zygotic embryo culture and growth of inflorescence tissues whereas, Blaydes medium was found suitable for anther culture. Y3 medium supplemented with 2.0 mg -1 NAA and 1.0 mg -1 kinetin was found the best for zygotic embryo culture. Immature zygotic embryos produced friable, nodular callus with higher embryogenic potential. White globular structures were produced when concentration of 2,4-0 was gradually reduced but regeneration was not obtained. Immature inflorescence rachillae explants produced friable callus when high levels of 2,4-0 was supplemented. Callusing was observed from microspores when L-glutamine 500 mg 1-1,2,4-02 mg l-1, coconut water 15 per cent v/v and 9 per cent sucrose were added to the Blaydes medium. But repeat- ability of callus induction was not obtained. Total phenol content, polyphenol oxidase activity and protein content were different in different plant parts and these factors indirectly affected the response of tissues under in vitro condition. Coconut is admittedly a recalcitrant material as far as tissue culture is concerned. Hence much more concerted efforts are required to develop a viable protocol for the micropropagation of coconut (Cocos nucifera) L. Nevertheless, the above mentioned observations on biochemical attributes points, in part, to the possible factors related to the recalcitrant behaviour of coconut in vitro.ThesisItem Open Access Effect of NPK and frequency of cuttings on yield and quality in amaranthus tricolor L.(Department of Olericulture, College of Horticulture, Vellanikkara, 1997) Deepa, Sukumar; KAU; Rajan, SAn experiment entitled "Effect of NPK and frequency of cuttings on yield and quality in Amaranthus tricolor L." was conducted at the Department of Olericulture, College of Horticulture, Vellanikkara during the period from October, 1995 to June, 1996 to study the effect of N PK and frequency of cuttings on yield and quality in amaranth variety Arun. The experiment was laid out in a (33 + 1)3 partially confounded factorial design with two replications. The NPK levels (N 50, 100 and 150 kg ha-1 ; P 50, 75 and 100 kg ha-1; K 50,75 and 100 kg ha-1) and cuttings (C0 - no vegetable harvest, C1 - one veget- able harvest and C2 - two vegetable harvests) had a significant impact on various growth, yield and quality characters. The plant height and the green yield increased with increasing levels of NPK. But the extent of increase was more with respect to nitrogen application. Application of nitrogen and phosphorus brought out significant decrease in the oxalate content (from 7.3% - 4.84%) upto the highest level tried (N 150 kg ha -1 and P 100 kg ha-I). But, potassium application increased the oxalate content significantly (from 5.7% to 6.44%). A clear cut increase in nitrate accumulation (from 0.17 % to 0.74%) was noticed with increasing levels of nitrogen. Nitrate accumulation was not significantly affected by phosphorus levels. In the case of potassium also there was a significant increase in nitrate content (from 0.17 % to 0.67%) though the extent of increase was less when compared to that of nitrogen application. The seed yield increased significantly due to increasing levels of all the three nutrients and plants with no vegetable harvest recorded the highest seed yield (1073 kg ha-1). Neither the nutrients nor the cuttings had significant effect on seed germination and seedling vigour. There was a significant increase in benefit-cost ratio with increasing levels of all the three nutrients. Plants from which one cutting was taken recorded the maximum benefit-cost ratio (2.35). So the optimum number of vegetable cuttings that can be taken from a seed crop so as to get maximum net return was found to be one. After taking one vegetable harvest (30 DAP) the crop should be left for seed production.