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Open Access
Studies on fertility status of rubber growing soils of Palakkad district
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1991) Mohanan, V; KAU; Nazeem, P A
Open Access
Character association of seeds on plant morphology in snakegourd (trichosanthes anguina L.)
(Department of Olericulture, College of Horticulture, Vellanikkara, 2000) Ashok, P; KAU; Rajan, S
The research project 'Character association of seeds on plant morphology in snakegourd (Trichosanthes anguina L.)' was carried out in College of Horticulture, Kerala Agricultural University, Vellanikkara, Thrissur during the period 1999-2000. The study envisaged to find out the association of various seed characters on the vegetative characters of snakegourd, classification of accessions based on the seed index, growth index and yield index as obtained from principal component analysis and to formulate keys for varietal identification. The 25 accessions were catalogued based on the IBPGR descriptor list. Significant differences for various seed characters, growth characters and yield characters were noticed among the accessions. Correlation studies have shown that the number of seeds per fruit strongly associated with days to male flower opening and fruit maturity. Seed size index was strongly associated with leaf size. The highest seed index value for TAl 08, the highest growth index value for TA 118 and the highest yield index value for TA 114 were obtained as revealed from principal component analysis . . Twenty five accessions were grouped into different clusters based on the seedindex, growth index and yield index. Based upon the seed characters (seed size, seed coat colour and 100 seed weight), growth characters (leaf lobes, leaf pubescence and tendril length) and fruit characters (fruit skin colour, fruit girth, fruit length and fruit weight) keys were developed for varietal identification.
Open Access
Quality Characters Of Clove And Nutmeg At Different Stages Of Maturity
(Department of Horticulture, College of Agriculture,vellayani, 1990) Manoj, A M; KAU; Vasanthakumar, K
The present investigation was carried out at the College of Agriculture, Vellayani during 1988 – 89. The objectives of this study were to characterise the growth pattern of clove flower buds and nutmeg fruits and to develop suitable harvest indices for these crops based on quality characteristics at different stages of maturity. The moisture content in clove buds and rind of nutmeg fruits increased with increase in maturity. However, moisture percentage in nutmeg kernel and mace was found to decrease as maturity advanced. The non – volatile ether extract (NVEE), on dry weight basis, was found to decrease on maturity advanced in clove buds and in mace while in nutmeg kernel the NVEE showed an increasing trend. The volatile oil in clove, nutmeg and mace was more at the immature stages and it progressively decreased at the peak harvesting stages. Eugenol, the chief component in clove oil was the maximum at the flowering stage. Hence for extraction of clove oil which is intended for use in medicine, dentistry and other pharmaceutical uses, it is advisable to harvest clove buds at the anthesis stage. The aromatic ethers which are the chief components that determine the flavour and drug action in nutmeg oil was the maximum one month prior to the fruit splitting stage. In mace oil it was found to be high two months prior to fruit splitting stage. So if nutmeg and mace oils are intended for medicinal purpose, then it may be worthwhile to harvest nutmeg fruits at the 6th month for extracting kernel oil and at the 5th month for extracting mace oil. Considering the fact that the nutmeg fruit yield both nutmeg and mace oil, harvesting separately at different maturity stages for extraction of the different oils is practically difficult. The aromatic phenol and phenol ethers showed a very low value in mace oil one month prior to fruit splitting. So in practice the fruit may be harvested two months prior to fruit splitting for extraction of both nutmeg and mace oils. However the high moisture content at this stage makes drying a problem. So such a practice of early harvesting of nutmeg fruits may be resorted to in places where facilities are available for extraction of oil from the fresh kernel and mace immediately after harvesting.
Open Access
Standrdisation of spacing for tissue culture banana cv. nendran (AAB group)
(Department of Horticulture, College of Agriculture, Vellayani, 1994) Anil, B K; KAU; Jayachandran Nair, C S
The investigation on “Standardisation of spacing for tissue culture banana cv. Nendran (AAB group)” was conducted at the Department of Horticulture, College of Agriculture, Vellayani, Thiruvananthapuram during, 1992-’93 inorder to study the effect of different spacings on growth, yield and fruit quality of Nendran banana. The results obtained are presented below: In the early stages of growth, the vegetative characters were not influenced by the spacings tried. However, during later periods, the plant height, girth, number of leaves per plant, total and functional leaf area, interval of leaf production, LAI and LAD increased with decrease in spacing. The time taken for bunch emergence, maturity and duration of crop increased with decrease in spacing. The number of suckers per plant decreased with decrease in spacing, while total number of suckers per hectare increased with decrease in spacing. The biomass and drymatter production per plant, bunch yield and fruit size were higher in wider spacing, while on per hectare basis it was the reverse. Drymatter content, TSS, reducing, non-reducing and total sugars and sugar/acid ratio of fruits increased with increase in spacing, while acidity and ascorbic acid content decreased. The time taken for ripening of fruits decreased with increase in spacing, while shelf life remained unaffected. The benefit/cost ratio was most favourable in 1.75 x 1.75 m spacing. Incidence of pests and diseases were severe in closer spacings above 1.75 x 1.75 m. Soil nutrient depletion was tolerable upto 1.75 x 1.75 m spacing, while uptake and partitioning of major nutrients by individual plants decreased with decrease in spacing. Fruits showed the highest nitrogen and phosphorus content followed by leaf, leaf sheath, corn and pseudostem. Potassium content was the highest in leaf followed by fruits, corm, leaf sheath and pseudostem. In general spacing 1.75 x 1.75 m did not significantly affect the plant growth, yield and quality of fruits. However, the experiment has to be repeated to arrive at conclusive results.
Open Access
Evaluation of nendran (musa aab group) ecotypem
(Department of Horticulture, College of Agriculture, Vellayani, 1996) Bindu Viveka, Devi; KAU; Jayachandran Nair, C S
The 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.
Open Access
Optimization of shade, nutrients and growth regulators for cut-flower production in anthurium
(Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, 1997) Salvy, B R; KAU; Valsalakumari, P K
Experiments were conducted at the Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, during 1995-1997 to optimize the shade, nutrients and growth regulators for cut flower production in Anthurium andreanum var. 'Hawaiian Red'. The effects of three growth regulators, viz., GA, BA and Ethephon with two concentration each, 750 ppm and 1500 ppm, in combination with four nutrients, viz., 1 % fertilizer complex, Hoagland solution, Knop's solution and Ohio solution, were assessed at four levels of shade, viz., 80, 70, 60 and 50 per cent. Post harvest studies were also carried out with an objective to prolong the longevity of cut blooms, following different stage of harvest and giving different pulsing and hold- ing treatments. Results revealed that the different levels of shade and growth regulators significantly influenced all the morphological characters of the plant, viz., height, spread, number of leaves, leaf area, petiole length, number of branches and suckers. Plant height was significantly superior under 80 per cent shade (5.68 cm), 1 per cent fertilizer complex sprays (5.46 cm) and BA 750 ppm sprays (6.11 cm), were superior individually. The superior treatment combination was 70 per cent shade + Knop's solution + 750 ppm BA (7.60 cm). The maximum plant spread (EW - 20.13 cm and NS - 19.80 cm) was under 80 per cent shade. Eighty per cent shade + Ohio solution + 1500 ppm BA recorded the maximum EW spread (26 cm), while NS spread was maximum (28.70 cm) in the treatment combination involving 80 per cent shade + 1 per cent fertilizer complex + 750 ppm BA. The best values of growth parameters were recorded under 80 per cent shade and 750 ppm BA, viz., 14.03 and 14.02, respectively, for number of leaves (9.29 and 10.79 cm, respectively) for petiole length, leaf length (7.76 and 8.33 cm, respectively), leaf breadth (5.93 cm and 6.49 cm, respectively), index leaf area (50.75 cm- and 59.60 cm-, respectively). Total leaf area (423.25 cm? and 517.56 cm>, respectively) and LAI (0.43 and 0.51, respectively) were maximum under 70 per cent shade and BA 750 ppm. The superior combinations for these parameters were 80 per cent shade + Ohio solution + 750 ppm BA, for highest number of leaves (26.20); 80 per cent shade + Ohio solution + 1500 ppm BA for highest petiole length (14.00 cm); 60 per cent shade + Hoagland solution + 750 ppm BA for maximum leaf length (10.50 cm) and 60 per cent shade + 1 per cent fertilizer complex + 750 ppm BA for maximum leaf breadth (8.0 cm). The treatment combination involving 70 per cent shade + 1500 ppm BA with Hoagland solution was the best for maximum index leaf area (90.90 cm-) while same with 1 per cent fertilizer complex was the best for total leaf area (872.00 cm-) and LAl (0.89). Branching started only after 6 months from the commencement of the experiment. It was one month earlier under 80 per cent and 70 per cent shade levels. Significantly superior branching was observed under 80 per cent shade (2.29), fertilizer complex (2.13) and GA 750 ppm (2.37), individually. Treatment combination involving 80 per cent shade + 1 per cent fertilizer complex + 1500 ppm GA recorded the maximum branching (3.80). .' . Sucker production was the best under 80 per cent shade (1.35) and 750 ppm BA (1.35). Treatment combination involving 80 per cent shade + Ohio solution + 750 ppm BA produced the maximum number of suckers (2.5) per plant. Growth behaviour with respect to height, number of leaves, leaf area, number of suckers and branches showed a linear trend. The linear growth rate was consistent and positive under the treatment combination of 80 per cent shade + Ohio solution + 750 ppm BA. Dry matter production was significantly superior under higher shade intensity and lower concentration of BA. The dry weight ratio of shoot:root was the highest (2.15) under the treatment combination of 80 per cent shade + Knop's solu- tion + 750 ppm Ethephon. Leaf longevity was significantly highest (161 days) in the treatment combination, 70 per cent shade + 1 per cent fertilizer complex + 750 ppm BA. Stomatal distribution and size were not influenced significantly by the treatments. Leaf senescence, though was influenced significantly, no particular trend was observed. The aerial root production decreased significantly with decrease in shade intensity. Primary and secondary roots and root spread were the highest under 80 per cent shade and BA 1500 ppm. Maximum root length was observed under 60 per cent shade. Flowering with small stalkless flowers was first observed under 50 per cent shade with GA 750 ppm, at the age of 8 months. Inflorescence with normal size were produced at the age of 13 months, first under 80 per cent shade followed by 70 per cent, 60 per cent and 50 per cent. The time taken for various stages of flower development and the number of inflorescence produced per plant were not influenced significantly. Chlorophyll content in leaf was significantly influenced by shade levels. There was a decrease in chlorophyll content with decrease in intensity of shade. Eighty per cent shade and 1500 ppm Ethephon was superior with respect to the content of green pigments. The highest total chlorophyll content was observed in the treatment combination involving 60 per cent shade + Ohio solution + 750 ppm Ethephon (8.8 mg g -1 fresh weight). Anthocyanin content was not influenced by any of the treatments or combinations. The leaf nutrient content and uptake of nutrients was maximum under 80 per cent shade and BA 750 ppm, individually. Post harvest studies showed that the right stage of harvest of inflorescence was when 1/3 flowers were open on the spadix. Inflorescence harvested at this stage with medium to large size spathe lasted for a longer period (23.33 days). Among the pulsing treatments, BA 50 ppm for 12 hrs, recorded maximum vase life (20.00 days). Among the different holding solutions tried, 8-HQ 30 ppm, BA 20 ppm and Triadimefon 30 ppm recorded the optimum values of PL W, uptake of vase solution, change in pH and EC, and recorded late spathe blueing, late spadix necrosis and high gloss retention. Highest vase life period (27.00 days) was recorded in 8-HQ 30 ppm (25.00 days) and Triadimefon 30 ppm (25.00 days). Among the combinations tried, BA 20 ppm + Bavistin 0.1 per cent showed longest vase life (23.67 days). Maximum net profit per pot (Rs.204.60) was recorded by the treatment combination involving 80 per cent shade + Ohio solution + 750 ppm BA.
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, R
Studies 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 bands
Open Access
Effect of planting density on the growth of rubber in the Vellanikkara estate
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1993) Karthikeyan, K V; KAU; Nybe, E V
The present observations on the influence of different planting densities on the performance of two clones namely RRII 105 and RRII 118 are in conformity with the results of other field experiments reported earlier. In lower planting densities, trees produced good girth, high yield per tree, thick virgin bark and high rubber content. Whereas, high planting densities contributed to poor tree girth, high yield per tree, thick virgin bark and high rubber content. Whereas , high planting densities contributed to poor tree girth, thin virgin bark and lower yield per tree. However, planting density is dependent on various other factors viz. topography of the land, system of planting to be adopted, the planting materials, cost of labour and price of rubber. Anyway, a comprise between labour cost and rubber price is needed. As far as small holders are concerned, a higher stand per hectare is preferred, since the question of labour does not arise. Therefore, for small holding sector a higher stand is recommended in order to get high per hectare yield. But there should be an optimum stand. In Malaysia, for small holders having available family labour, a planting density of approximately 740 trees per hectare is recommended. However, indepth studies are required for a meaningful recommendation in our country. Salient results The trees were taller in high density planting The trees were more vigorous in low density planting. The highest mean girth of 64.7 cm was recorded by RRII 118 at a population density of 420 plants/ha.The percentage of weaklings increased with increase in population.The highest weakling percentage of 35.8 was recorded by the planting density of 824 plants per hectare. Poor bark growth in high density planting Per tree yield was more for low density planting whereas per hectare yield was less. With regard to high density planting , per tree yield was less and per hectare yield was more. Dry rubber content (drc) was more in low density planting. The highest percentage of 44.5 was recorded by RRII 118 at a planting density of 420 plants/ha. Light penetration was more in low density planting. The maximum light penetration recorded was 110.0 micromole/sec/m2 at a density of 420 plants per hectare.
Open Access
Enhancing the in vitro response of explants from mature jack (artocarpus heterophyllus lam.) trees
(Department of Horticulture, College of Agriculture, Vellayani, 1993) Reena, Philip; KAU; Rajmohan, K
The objective of the present study was to improve the propagation efficiency of mature phase jack trees by various pretreatments. The treatments tried involved stock plant treatments, explants treatments and in vitro treatments. Surface sterilization with HgCl2 for 13 minutes was found to be the most effective in reducing microbial contamination during culture establishment. Among the stock plant treatments tried, grafting on to juvenile rootstock was found to be the most effective in improving the in vitro response of explants from mature jack trees. Stress treatments were found to be the most effective among the explants treatments. Cold shock for 5 minutes at – 200C was found to produce the best results followed by heat treatment at 420 C for 2 minutes. Among the in vitro treatments, incorporation of phloroglucinol at the rate of 10mg/l was found to be the most effective. The results also showed significant influence of season on the response of mature explants, the highest response being observed during March – April.

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