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Open Access
Nutrient requirement for bush jasmine (Jasminum sambac ait.)
(Department of Horticulture, College of Agriculture, Vellayani, 1999) Asha, Raj; KAU; Sheela, V L
The investigation "Nutrient requirement of bush jasmine, Jasminum sambac Ait." was conducted at Department of Horticulture, College of Agriculture, Vellayani, Thiruvananthapuram during 1996-'98 inorder to standardise the requirement of major nutrients (N, P and K) for the growth of flowering of bush jasmine. The treatments consisted of factorial combinations of three levels each of nitrogen (50, 100 and 150 kg N ha"), phosphorus (50, 100 and 150 kg P20S ha-I) and potassium (50, 100 and 150 kg ~20 ha") with two controls. The experiment was laid out as 33 + 2 Factorial Randomised Block Design with three replications .. Vegetative characters like the length of main shoot, number of primary and secondary branches, length of primary and secondary branches, North-South and East-West spread of the bush, were significantly higher at the highest level of major nutrients viz., 150 kg N, 150 kg P20S and 150 kg K20 ha'. At the maximum level of major nutrients with 150 kg N : 150 kg P20S : 150 kg K20 ha'", yield of flower buds was found significantly higher. Other flowering characters like monthly yield pattern and weight of hundred flower buds were not found to be influenced by nutritive 2 treatments. However, time taken for opening of lower buds after harvest was maximum at 150 kg P20S ha'". Content of N, P and K in leaves revealed that maximum content of foliar nitrogen noticed at 150 kg N : 50 kg K20 ha! while foliar potassium content was maximum at 50 kg N : 100 kg P20S : 150 kg K20 ha'. Foliar phosphorus content was not at all influenced by nutrient application. Uptake of nutrients was not found to be influenced by applied nutrients where as DMP was maximum at the highest dose of maj or nutrients (150 kg N : 150 kg P20S 150 kg K20 ha"). Available soil nutrient status revealed that maximum content of nitrogen and phosphorus in soil was noticed at 150 kg N : 150 kg P20S and 150 kg K20 ha'". But maximum available potassium was noticed with 50 kg N : 150 kg P20S and 150 kg K20 ha'. Maximum essential oil content was obtained with 100 kg N : 100 kg P20S and 150 kg K20 ha'". Carbohydrate content of flowering shoot was found to be highest with 50 kg N : 150 kg P20S : 150 kg K20 ha-I. In general, highest dose of major nutrients, n3 (150 kg N ha-I), P3 (150 kg P20S ha! and k3 (150 kg K20 ha") was found best for cultivation of bush jasmine. However, as maximum response was shown at respective higher levels of major nutrients, higher levels of these nutrients can be tried to find out optimum nutrient combination for commercial cultivation.
Open Access
Improvement of in vitro somatic embryogenesis in cashew (Anacardium occidentale L.)
(Department of Horticulture, College of Agriculture, Vellayani, 1999) Rekha, S; KAU; Sulekha, G R
Studies were conducted for improving techniques for in vitro somatic embryogenesis in cashew during 1996-1999 in the Plant Tissue Culture Laboratory of the Department of Horticulture, College of Agriculture, Vellayani. Attempts were made to standardise the various stages of somatic embryogenesis, namely, induction, initiation, maturation and germination using nucellus and embryo mass as explants. Out of the two explants tried, nucellus responded better than embryo mass in initiating embryogenic callus/somatic embryoids. Induction of somatic embryogenesis from nucellus was found to occur at its maximum when cultured in darkness on MS basal medium having half strength major salts, supplemented with 2,4-D 1.0 mg/l, BA 1.0 mg/l, NAA 1.0 mg/l, sucrose 30.0 g/l, Activated charcoal 0.5 g/l and agar 6.0 g/l. The best treatment identified for the induction of embryogenic callus / somatic embryoids from embryo mass was MS basal medium supplemented with 2,4-D 4.0 mg/l, NAA 4.0 mg/l, kinetin 4.0 mg/l, adenine sulphate 40.0 mg/l, yeast extract 200.0 mg/l, PVP 250.0 mg/l, sucrose 30.0 g/l and agar 5.5 g/l, in dark culture condition at regulated temperature (26 ± 2°C). 2 Initiation of somatic embryoids from nucellus as well as embryo mass occurred at its best in darkness on MS basal medium supplemented with NAA 0.5 mg/l, kinetin 2.0 mg/l, adenine sulphate 40.0 mg/l, PVP 250.0 mg/l, yeast extract 200.0 mg/l, sucrose 30.0 g/l and agar 5.5 g/l. . Among the treatments tried for inducing proper maturation of the somatic embryoids, the maximum survival of embryoids was recorded on a combination of basal media with Bs major salts and MS minor salts supplemented with ABA 1.0 mg/l, coconut water 200.0 mlll, casein hydrolysate 100.0 mg/l, PVP 10.0 g/l, sucrose 40.'0 g/l and agar 5.0 g/l. Culture conditions did not influence the maturation process of the somatic embryoids. Maturation process was not found to be essential in inducing normal germination of the somatic embryoids. The cultures showed good response when subcultured from initiation media to germination media without a maturation phase. Germination of somatic embryoids occurred only in the presence of light, on a combination of basal media with Bs major salts and MS minor salts supplemented with BA 1.0 mg/l, PVP 10.0 g/l, coconut water 200.0 mlll, sodium chloride 0.1 per cent, cobalt chloride 10.0 g/l, sucrose 50.0 g/l and agar 6.0 g/l.
Open Access
Isoenzyme variation in curcuma with special reference to Curcuma longa L.
(Department of Plantation Crops and Spices,College of Horticulture, Vellanikkara, 1999) Renu, Joseph; KAU; Sujatha, V S
The study on 'Isoenzyme variation in Curcuma with special reference to C. longa was conducted in the Department of Plantation Crops and Spices and Biochemistry laboratory at College of Horticulture, Vellanikkara, Thrissur from October 1997 to June 1999. Eighteen species of genus Curcuma, including C. longa were included in the study. Thirty three accessions of C. longa were selected to represent 21 morphotypes of Velayudhan et al. (1994). Six released varieties were also studied. These were analysed for three enzymes viz. peroxidase, esterase and GOT using polyacrylamide gel electrophoresis. The selection of ideal part for electrophoresis for each enzyme was done based on observations of banding pattern of root, rhizome, sprout and different maturity stages of leaf. Sampling and analysis was done during three weeks after sprouting and just before senescence of leaf to standardise the stage of growth of plant. Mature leaf just before its senescence was selected for peroxidase and GOT analysis. Tender leaf three weeks after sprouting was found to be ideal for esterase. lsoenzyrne banding pattern of 39 genotypes of C. longa were studied for esterase, peroxidase and GOT. The similarity index among the genotypes ranged from 0.39 to one. The genotypes were classified into 21 groups with similarity index one among the members. Morphotypes M-I, M-2 and r'A-3 ofVelayudhan et 01 (1994) formed one group with similarity index one. M-7 and M-8 were also grouped into one. Released varieties under study showed more similarity with first group of morphotypes. On grouping the [8 species of Curcuma based on isoenzyme similarity C zedoaria, C. aeruginosa, C. malabarica, C. comosa and C. cacsia formed one group, C. amada, C. syivatica, C. aromatica and C. liarita the second group and C. soloensis, C. brog and C montana the third group. Cultivated type C longo and other sessile tuberising species C. latifolia and C. raktakanta showed variable similarity with other species and stood independently. Stoloniferous type C. vamana showed more similarity with sessile tuberising species than with non-sessile tuberising species, Non-sessile tuberising species C. aurantiaca and C. pseudomontana stood individually showing their distinctness from rest of the species.
Open Access
Influence of post-bunching sprays of cytokinin, potassium and calcium on yield and shelf life of banana (Musa AAB Nendran) fruits
(Department Of Pomology And Floriculture, College Of Horticulture, Vellanikkara, 1999) Sindhu, T S; KAU; Sajan Kurian
The experiment entitled " Influence of post - bunching sprays of cytokinin, potassium and calcium on yield and shelf life of banana (Musa AAB Nendran) fruits" were carried out in the Department of Pomology and Floriculture, College of Horticulture, Vellanikkara. The study was investigated during two seasons from 1997 to 1999 with the objective of increasing the yield and shelf life by bunch management sprays in plants which had been given bunch stalk feeding of urea, primarily by use of a nutrient viz., potassium; secondly by use of a nutrient which acts in preserving the integrity of the cell wall viz., calcium and thirdly, a plant growth regulator with known anti- senescence properties viz., cytokinin. The study emphasized the overall superiority ofMpercent.K2S04 sprays applied at third and fourth week after bunch emergence. Yield and yield components like the finger characters such as length, grade and FCr were improved by the treatments. A delay in maturity and ripening and an extended shelf life were observed. The quality of treated fruits revealed reduced acidity, increased sugar contents, higher urease activity, lower residual urea and lower levels of nitrite nitrogen. Electrolytic leakage was also less in K treated fruits. Among the cytokinin treatments 50 mg l' of kinetin and 75 mg r' of BA applied at third and fourth week after bunch emergence proved better. Yield and yield parameters i.e., bunch weight and finger characters such as length, grade and FCr were significantly improved by the bunch management practises involving post- bunching sprays of cytokinin. The. kinetin sprays delayed maturity and ripening besides, qualitatively improving the shelf life. Calcium infiltration technique could reduce the percentage reduction in finger weight significantly and qualitatively increase shelf life. Also an increase in quality by way of reduction in acidity and increase in total soluble solids, especially in calcium infiltration treatments was observed. The electrolytic leakage of fruits was found to be less in calcium infiltrated fruits and above all, the effective treatments were more acceptable in terms of taste. The calcium content in the pulp and peel were increased due to infiltration. Analysis of the calcium content in calcium treated fruits revealed that calcium content was more in the peel than in the pulp. Sensory evaluation carried out by a taste panel revealed that consumer acceptability of treated fruits was in no way reduced.
Open Access
Estimation of genetic parameters from specific crosses of cocoa (Theobroma Cacao L.)
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1999) Sridevi, R; KAU; Prasanna Kumari Amma, S
The research project entitled 'Estimation of genetic parameters from specific crosses of cocoa (Theobroma cacao L.)' was carried outean ongoing experiment of Cadbury-KAU Co-operative Cocoa Research Project (CCRP), College of Horticulture, Kerala Agricultural University, Vellanikkara, Thrissur during 1998-99. The studies were conducted in four year old hybrids. The major objectives were to study the genetic variability, heritability, correlation of different traits with yield, extent of heterotic expression of various traits and to examine the association between seedling vigour and yield. Twenty five cocoa hybrids were maintained in randomised block design with three replications. The hybrids exhibited significant variability for most of the traits studied. The estimates of pev were higher than gcv for all the traits studied. The highest heritability was recorded for number of beans per pod and seedling vigour recorded as °HD2 (6 MAS) had a high genetic gain. Yield and number of pods per tree recorded moderate genetic gain. Yield was found to be significantly and positively correlated with number of pods per tree, height (2 YAP) and girth (2 YAP) of the tree. Absence of significant correlation between yield and seedling vigour was observed. Path analysis revealed the importance of pod number per tree and wet bean weight per pod in determining yield. Yield and number of pods per tree showed a very high heterotic expression in most of the hybrids. Among the 25 cross combinations H23 was identified as the superior cross combination followed by H16 and H; The parents of these cross combinations can be used for raising biclonal seed gardens, as they had a good specific combining ability. The floral traits did not vary markedly in the hybrids. However the qualitative traits exhibited wide variation in the different hybrids.
Open Access
Biomass production and partitioning of photosynthates in ginger (Zingiber Officinale R.) under different shade levels
(Department of Horticulture, College of Agriculture, Vellayani, 1999) Sreekala, G S; KAU; Jayachandran, B K
A pot culture experiment was conducted at the College of Agriculture, Vellayani during the year 1997 - 1998 to study the effect of shade on biomass production and partitioning of photosynthates in ginger cv. Rio-de-Janeiro. The experiment was laid out in completely randomised design with five shade levels (open, 20, 40, 60 and 80 per cent) and four replications. Artificial shade was provided using high density polyethylene shade nets and calibrated using quantum photo sensors. Two months after planting, ginger plants were labelled using 14C . After tagging, one set of samples were collected immediately. Subsequently, harvesting of the tagged plants were done once in sixty days after labelling. Monthly observations of various growth parameters were taken from two months after planting. At six months after planting photosynthetic related parameters were measured using leaf chamber analyser. The various growth parameters like number of tillers, leaf area, leaf dry weight, dry matter production, crop growth rate, relative growth rate, net assimilation rate at final stage, leaf area index which contributed to yield was highest under 20 per cent shade. This shows that the plant prefers low shade intensity compared to open. The yield recorded under 20 per cent shade was significantly superior compared to open. But the yield at open and 40 per cent shade were on par. Higher shade levels decreased the yield. This shows that the crop can tolerate shade up to 40 per cent. Different shade levels influenced the quality of ginger rhizomes. While volatile oil was maximum under heavier shade levels in general ( 60 and 80 per cent ), non- volatile ether extract was higher under 20 per cent shade. Starch as well as crude fibre content was more in plants grown under open condition. The photosynthetic rate and related parameters of ginger were measured at six months after planting using leaf chamber analyser. Photosynthetically active radiation on leaf surface as well as stomatal conductance was high under open condition. But leaf internal carbon dioxide concentration as well as stomatal resistance was high under heavier shade levels (60 and 80 per cent). Photosynthetic rate as well as the transpiration rate was maximum in plants grown in open. Though, at 20 per cent shade, the photosynthetic rate was less, the yield was high. This might be because of the photo oxidation that has taken place at high light intensities or due to the inefficient translocation of the photosynthates in open condition compared to 20 per cent shade. Radio tracer analysis done using labelled 14C has shown that under open condition, though initial intake of carbon dioxide was more, most of the carbon dioxide taken are seen in the above portion itself. While in 20 per cent shade most of the carbon dioxide taken in has translocated to the lower portion. This shows that under low light intensity the photosynthates produced has translocated efficiently to the lower portion while in open condition efficient translocation has not taken place. The results indicate that 20 per cent shade level is favourable for growing ginger plants to get higher rhizome yield. The yield at 40 per cent was on par with that of open. This shows that crop can tolerate shade upto 40 per cent. Thus the partially shaded coconut gardens can be exploited for increasing the area under ginger which may help in doubling the production.
Open Access
Evaluation of in vitro multiplied accessions of pineapple (Ananas comosus (L.) Merr.) CV. Mauritius
(Department of Pomology and Horticulture, College of Horticulture, Vellanikkara, 1999) Pattabi Raman, S; KAU; Radha, T
Investigations on "Evaluation ef in vitro multiplied accessions of pineapple (Ananas comosus [L.] Merr.) cv. Mauritius" were carried out in the Department of Pomology and Floriculture, College of Horticulture, Vellanikkara during 1997-1999. The major objective of the study was to evaluate the field performance of tissue culture plants of elite accessions against the tissue culture plants of unselected bulk and conventional suckers under varied fertilizer doses, to ascertain the superiority of the former over the later two and to isolate the elite accessions. During the early stage of crop growth, sucker derived plants recorded higher values for almost all the vegetative characters studied, whereas from six months after planting tissue culture plants of elite accessions were on par with sucker and showed significant superiority over the unselected bulk. Total dry matter production as well as dry matter partitioning were higher for tissue culture plants of elite accessions than tissue culture plants of unselected bulk. The former also showed early flowering with longer flowering phase than the later. The fruit and yield parameters also showed superiority of tissue culture plants of elite accessions over that of unselected bulk and the values were on par with suckers. Among the elite accessions, TK 3 (Ti) and KT 5 (T2) performed well and recorded the maximum estimated yield (77.0 tonnes), whereas tissue culture plants of unselected bulk recorded an estimated yield of 49 tonnes only. There was not much variation among the treatments in all the quality parameters studied, except for TSS:Acid ratio All the tissue culture plants including unselected bulk produced more number of suckers and slips than sucker derived plants. The salient outcome of the present investigation with respect to two fertilizer doses was that, M, showed significant superiority and recorded a lesser crop duration of one month than M\ in all TC plants when compared to that of suckers. The results of the present investigation undoubtedly proved the r- superiority of elite accessions over that of unselected bulk, indicating the importance of clonal selection for crop improvement. Results also proved the requirement of higher dose of fertilizers and split application of the same during early vegetative stage to boost up the growth of plants and to reduce the total duration of the crop. Among the elite accessions KT 3 and TK 2 performed well than others and hence can be recommended for further evaluation and yield trials.
Open Access
Response of turmeric Curcuma domestic val. to in vivo and in vitro pollination
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1999) Renjith, D; KAU; Valsala, P A
Investigations on "Response of turmeric Curcuma domestica Val. to in vivo and in vitro pollination" were carried out at the Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara during 1997 to 1999. Research was carried out with turmeric cultivars viz. VK 70, VK 55, VK 76, Suguna, Sudharsana, Suvarna, Kanthi and Sobha. Among them, Kanthi and Sobha were medium duration types and the rest were short duration types. The selected cultivars differed significantly with respect to morphological and qual~ty characters. The curcurmin content was high in Sobha (7.43%), Kanthi (7.02%) and in VK 76 (6.38%) while all others recorded <5.1 percentage. The cultivars VK 70 (21.5%), VK 76 (20.0%) and Suvarna (19.5%) were noted for high curing percentage. The floral biology and morphology of turmeric were studied. Turmeric cultivars took 105 to 155 days for flowering and the flowering season ranged from July to October. The anthesis started by 5 am and continued up to 6 am. Anther dehiscence took place between 7.15 am and 7.45 am. Androecium consists of six stamens in two whorls of three each. The outer whorl is modified as labellum. The inner whorl is represented by two staminodes and one fertile stamen. Gynoecium has a long style of mean length 4.43 cm. The ovary measured a mean length of 2.6 mm and diameter of 2.4 mm and recorded a mean ovule number of 29.31. The ovules recorded a mean length of 611.44 urn and breadth of 436.65 urn at the middle. At the base of the flower honey secretion is present and ants are the pollinating agents. The mean pollen fertility with acetocarmine stain in the studied cultivars were 78.51 per cent. Attempts to develop a medium which will support pollen germination and tube growth in turmeric resulted in the identification of modified MEJ medium of pH 6 (Leduc et al., 1990). The pH reactions of the medium influenced the pollen germination . . Pollen germination was high in short duration type (23.75 to 46.08%) compared to medium duration types (8.22 to 11.50%). The pollen tube length also was higher in short duration cultivars (268.48 urn to 576.3 urn) compared to medium duration cultivars (218.72 urn to 245.45 urn). Pollen germination was influenced by the position of flowers in the inflorescence. The germination was high in the flowers at the lower portion (32.55%) and low in the upper portion (22.93%) of the inflorescence. The optimum time for collection of roots for mitotic studies in turmeric was between 6.30 am and 7 am. The somatic chromosome number of short duration cultivars viz. VK 70 and Suvarna were found to be 2n = 84 and that of medium duration cultivar Kanthi as 2n = 63. Natural fruitset and seed set were observed in short duration cultivars and not noticed in medium duration cultivars. The natural pollinating agent in turmeric is insects i.e., ants. Through controlled in vivo pollination, seed set was obtained in crosses involving short duration cultivars but failed in crosses involving short and medium duration cultivars. The fruit of turmeric is a thick walled trilocular capsule with small black I arillate seeds. Seeds are filled with massive endosperm and embryo is seen towards the upper side of the ovule. Initial studies for culture establishment showed that the basal medium of Y2 MS and MS are suitable. The half strength MS being superior to full strength MS. Various antibiotics tried for controlling bacterial contamination m cultures were in effective. Studies were made to standardize optimum media components for ovule development. The combination ofNAA 0.5 mg r' with BAP and kinetin both at 1 mg r' induced maximum ovule swelling. On visual assessment, 3 per cent sucrose concentration was superior to 6 per cent level for ovule development. Organic . 1 supplements, coconut water (15% v/v) and CH (200 mg I") enhanced ovule development. In vitro pollination was done by pollen grains suspended in modified ME3 medium. Among the various methods of pollination tried, ovules/seeds development were observed in the intra ovarian, placental and modified placental pollination techniques. These techniques can be used for conducting crosses involving short and medium duration cultivars provided medium duration cuItivars used as female parents. In the intra-ovarian pollination fruit development occurred. The ovary developed into fruit and attained a maximum size of 6 mm 20 OAP under in vitro condition. Ovules/seeds developed after in vitro pollination were creamy white during the initial stage of development and changed to dark brown colour within a period of 20 to 30 DAP. In the in vitro developed seed the endosperrn development was not complete. The seeds developed under in vivo, germinated under in vitro on moist filter paper.
Open Access
Screening and biochemical characterization of tomato genotypes for resistance to bacterial wilt
(Department Of Olericulture, College Of Horticulture, Vellanikkara, 1999) Subash Chandra Bose, S; KAU; Rajan, S
Investigation on 'Screening and biochemical characterization of tomato genotypes for resistance to bacterial' wilt' was carried out in the Department of Olericulture, and Biochemistry Laboratory, College of Horticulture, Vellanikkara 1 during 1997-99. The objectives of this study were to identify tomato genotypes resistant to bacterial wilt and to find the possibility for biochemical cataloguing of bacterial wilt resistant tomato genotypes. Evaluation for bacterial wilt resistance revealed that Sakthi, Mukthi and LE-474 were consistently resistant to bacterial wilt. Four additional sources of bacterial wilt resistance were identified, viz. LE-214, LE-415, LE-470 and LE-421. Based on the percentage wilting the twenty four genotypes included in this study were classified into four groups, viz. Resistant, Moderately Resistant, Susceptible and Highly susceptible. -.: All the bacterial wilt resistant and moderately resistant genotypes had a higher content of total phenols in roots and leaves at 45th and 60th day of plant growth; O.D. phenol content in roots of resistant varieties were higher than susceptible varieties. In leaf, the O.D. phenol content was high in moderately resistant genotypes at 45th and 60th day. All the genotypes were studied for isozyme variation with respect to two enzymes, viz. polyphenol oxidase and peroxidase. 10 general the roots had more number of bands compared to leaves at both the stages. '.. The root samples at 45th day showed two polyphenol oxidase bands, viz. PPO-I (~=0.074) and PPO-12 (Rm=0,414) which were specific to resistant varieties alone. This combination along with high total phenols may be considered as a biochemical marker for resistance to bacterial wilt in tomato. In 60 days old roots of resistant and moderately re istant genotypes the protein band PPO-9 (Rm=0.851) was predominantly present Regarding peroxidase, 45 . days old leaf samples had a combination of protein bands, viz. PRX-7 (Rm=0.361) and PRX-8 (Rm=O.382) in resistant and moderately resistant varieties. But at 60 days the roots and leaves did not show any specific band for resistance. In general at 45 days both leaf and root samples had more number of bands for polyphenol oxidase and peroxidase in resistant varieties compared to susceptible varieties. The study revealed that it was possible to arrive at a combination of specific isozyme bands at a particular growth stage, which can be used as a marker for bacterial wilt resistant tomato genotypes.

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