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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
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
Standardisation of propagation techniques in schefflera
(Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, 1997) Sunitha Anne, Mathew; KAU; Murali, T P
The 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.
Open Access
Environmental effects on the growth of philodendron wendlandii
(Department of Pomology & Floriculture, College of Horticulture, Vellanikkara, 1996) Swapna, S; KAU; Geetha, C K
An 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.
Open Access
Performance of selected orchids under varying light regimes, culture methods and nutrition
(Department of Horticulture, College of Agriculture, Vellayani, 1996) Sabina George, Thekkayam; KAU; Mohanakumaran, N
The present study was undertaken to evolve agrotechniques for cut flower orchid production in Kerala. Two experiments were conducted at the College of Agriculture, Vellayani in 1991 and 1992 with two popular cut flower varieties namely Arachnis Maggie Oei ‘Red Ribbon’ and Dendrobium Sonia – 16. The effects of varying light intensities and nutrient regimes under two methods of cultivation were assessed in Arachnis Maggie Oei ‘Red Ribbon’ (Experiment 1) and in Dendrobium Sonia -16, the performance under varying light intensities and nutrient regimes was evaluated (Experiment 2) In Arachnis Maggie Oei ‘Red Ribbon’, trench culture was found to promote growth, flowering and the floral attributes. The number of leaves, aerial roots, leaf area and plant height were greater in the trench grown plants. The number of inflorescences produced, their branching, length and vase life were also enhanced under trench culture. The effect of light intensities on growth was mediated through interactions with culture methods and nutrients. The trench grown plants under 50 and 75 percent light had a greater number of leaves and leaf area. The plants receiving 500 ppm of P and K under 100 percent light had a shorter stature. The direct effect and interactions of nutrients on growth were observed at certain months during the experimental period which was indicative of differences in the requirement at different stages of growth. The dry matter content of the stem and apical shoot was greater in the plants receiving 500 ppm P. Inflorescence production and the vase life of inflorescences was greater under 100 and 75 percent light. Branching of inflorescences was greater under 75 percent light. In Dendrobium Sonia -16 the number of inflorescences produced was greatest under 75 percent light. The length of the inflorescences was greater under 75 percent light and the span area of the flowers was greater under 50 and 75 percent light. Nitrogen at 500 ppm increased the length of the inflorescences, the number of flowers in an inflorescence, and the span area of the flowers. The number of inflorescences produced was also greater in the plants receiving 400 or 500 ppm N, 400 or 500 ppm K and in those receiving 500 ppm P. Interactions between the nutrients and between light intensities and the nutrients were also observed. The nutrient composition of the leaves in both the cultivars were enhanced by the 400 and 500 ppm doses of N and P and 500ppm K. Based on the observed effects, in Arachnis Maggie Oei ‘Red Ribbon’, trench culture of plants under 75 to 100 percent light and a nutrient dosage of 300 ppm N, 400 ppm P and 300 ppm K from planting till nine MAP and thereafter a dosage of 400 to 500 ppm N, 400ppm, P and 500 ppm K can be recommended. In Dendrobium Sonia -16 growing in pots under 75 percent light with 400 to 500 ppm of N, P and K can be recommended
Open Access
Cyto-morphological investigations in piper spp.
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1997) Ambili, Anand; KAU; Sujatha, V S
The 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.
Open Access
Somaclonal variation in black pepper (piper nigrum L)
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1996) Shylaja, M R; KAU; Sreekandan Nair, G
Investigations on the exploitation of somaclonal variation for screening for resistance to Phytophthora foot rot disease in black pepper were carried out at the Plant Tissue Culture Laboratory of the Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara during September 1991 to January 1995. Calliclones of different black pepper cultivars viz. Kalluvally, Cheriakanyakkadan, Balankotta, Karimunda and Panniyur – 1 were produced with and without applying in vitro selection pressure using toxic metabolite(s) of Phytophthora capsici. In vitro induction of mutation using gamma irradiation and partial purification of the toxic metabolite(s) present in the culture filtrate of P. capsici were also attempted in the present study. Leaf puncture bioassay of the concentrated culture filtrate (CCF) of P. capsici showed that toxic metabolite(s) were accumulated in the culture filtrate. The symptoms produced by CCF were quite typical of natural and artificial infection by P. capsici. Concentrated culture filtrate induced quick electrolyte leakage from leaves and calluses. Concentrated culture filtrate induced necrosis on susceptible calli. The cultivars showed significant variation in callus necrosis. Prolonged duration of selection/screening with CCF totally inhibited the regeneration potential of the calli. Concentrated culture filtrate was not found to inhibit shoot proliferation and shoot growth in already regenerated cultures but inhibited the root growth. In the three direct selection/screening methods tried for calli viz. growing in CCF incorporated MS medium (Method 1) shaking in CCF incorporated liquid MS medium (Method 2) and double layer culture technique (Method 3), cultivars showed significant differences in callus necrosis and callus growth. Direct screening of calli was not found to inhibit the regeneration of shoots, shoot proliferation and recovery of rootable shoots but affected the root growth adversely. Gamma irradiation of calli using 60Co source did not give any better response to in vitro screening. The toxic metabolite(s) present in the culture filtrate could not be separated by organic solvent fractionation. However ion exchangers like Dowex 1 and Dowex 50 could be used for separation of the toxic fraction from the filtrate. The response of five different cultivars at various stages of development of cultures when compared, it was found that the cultivars differed significantly in callusing, callus growth, regeneration of shoots, recovery of rootable shoots and root growth. The clones regenerated from screened and unscreened calli were further tested for resistance/ tolerance to P. capsici using different methods of screening viz.natural screening (keeping in infected field), screening by electrolyte leakage method and screening by artificial inoculation of culture disc of P. capsici. None of the regenerated calliclones were found to be resistant to the disease in natural screening. When the tolerance level of the regenerated calliclones was looked into, the performance of the unscreened calli derived clones was found better as compared to the screened calli derived ones. The calliclones of different cultivars differed significantly inthetolerance/susceptibility reaction to the disease. The calliclones of Cheriakanyakkadan recorded greater degree of tolerance to the disease when compared to others. Among the cultivars studied, Kalluvally exhibited high rate of somaclonal variation.

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