Browsing by Author "Pushkaran, K"

Now showing 1 - 18 of 18

Analysis of yield and its components in sweet potato (Ipomoea batatas L.)
(Kerala Agricultural University, 1976) Pushkaran, K; Sukumaran Nair, P; Gopakumar, K
Analysis was carried out for studying the yield-component inter-relationship in seventeen varieties of sweet potato. Determination of the coefficients of simple and mutual correlations and path at the levels of the first and second order components reveals that an increase in the length of vine causes significant increase in tuber yield. But at the same time, the overall area of leaf should not be allowed to increase, because this character bears a negative relationship with yield. An ideal plant type with longer vines, w i i i i small, narrow and deeply lobed leaves with appropriate orientation on the viue for effecting better photosynthetic efficiency, should be aimed at for selecting potentially high yielders.
Banana Compendium
(Kerala Agricultural University, 1996) Aravindakshan, M; Pushkaran, K
Biometric analysis of yield and other attributes in coleus
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 1996) Prakash, K M; Pushkaran, K
Studies were undertaken with thirty genotypes of coleus in the Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara during 1995-96 to estimate the extent of genetic variability, association among the selected characters and its partition into direct and indirect effects through path coefficient analysis under open as well as shaded conditions. The results have shown that the differences between the types were highly significant for most of the characters in the open condition and for all the characters in shaded condition. Low heritability and low genetic advance were shown for most of the economically important tuber characters in the open while the heritability and genetic advance were much greater in the shaded for the economically important characters. Expected genetic advance has shown that by selecting five per cent superior plants from available population, tuber yield could be increased by 52 g per plant in the shaded condition. Correlation studies have indicated that shoot characters like shoot length, number of leaves per plant and leaf area per plant and tuber characteristics like number of tubers per plant, tuber girth and tuber length are highly correlated with yield under open condition. However under shaded condition all the shoot characters are negatively correlated and all the tuber characters like number, length, girth and individual weight are to be given emphasis for identifying a high yielding genotype because of their high positive genotypic correlation with tuber yield. Path analysis projects that greater emphasis has to be laid for improving girth of tuber, number of tubers per plant individual tuber weight and tuber length in the open condition in selection while number of tubers, individual tuber weight and tuber girth should be given emphasis when selection is done for tuber yield in shade grown coleus.
Combining ability analysis for yield and yield components in rice varieties of diverse origin
(Kerala Agricultural University, Vellanikara, 2003) Vanaja, T; Luckins C, Babu; Radhakrishnan, V V; Pushkaran, K
Correlation and path analysis in groundnut in the summer rice fallows
(Kerala Agricultural University, 1988) Pushkaran, K; Gopinathan Nair, V
Pod yield and seventean other characters were studied in eighty groundnut varieties raised in summer rice fallows. Correlation coefficients at the genotypic and phenotypic levels were computed between these characters and path analysis for pod yield was carried out considering eight components. Dry pod yield was highly correlated positively with plant height on the 50th day, length of top, fresh weight of pods, number of mature pods and number of immature pods both at the genotypic and phenotyic levels. Pod yield was also correlated highly and positively with number of flowers and haulms yield phenotypically. Pod yield recorded highly significant negative correlation with duration upto flowering, number of branches and leaves on the 50th day and number of flowers while it was moderate with number of branches. Positive correlation of duration upto flowering and maturity and lack of significant correlation of the latter with pod yield suggest the possibility of recombining high yield with short duration. Fresh weight of pods had the highest positive direct effect on dry pod yield. Number of leaves, flowers and mature pods also had positive direct effects in that order. Number of mature pods exarted positive indirect effects via fresh weight of pods, number of basal primary branches, haulms yield and 100 pod weight. Length of top, numbar of basal primary branches, haulms yield and '00 pod weight had negative direct effects on pod yield, of which that by haulms yield was the highest.
Correlation studies in groundnut
(Kerala Agricultural University, 1993) Pushkaran, K; Gopinathan Nair, V
For effecting dependable selection in breeding groundnut varieties suited to kharif uplands and summer rice fallows, genotypic correlation studies and path analysis were done based on 18 characters collected from 80 divergent groundnut varieties and the results compared and contrasted. There are differences in the direction, degree of relationship and relative effects for important characters on the economic trait on both the situations. Hence, in selecting ideal genotypes for the two situations, differential considerations had to be given for the component characters.
Effect of certain agronomic practices on the performance of kokkan affected nendran banana
(Kerala Agricultural University, 1992) Nybe, E V; Pushkaran, K; Suma, A; Darley Jose
The effects of certain agronomic practices on the performance of kokkan affected banana, cv. Nendran were studied at the Banana Research Station, Kannara during 1987. The results of the study revealed that the different agronomic practices such as application of K at double the recommended dose, MgSO4, fresh cowdung and neem cake snowed no significant improvement in kokkan affected plants with respect to yield, yield contributing characters and overall appearance of the bunch.
Evaluation of groundnut for kharif uplands and summer rice fallows
(Kerala Agricultural University, 1985) V Gopinathan Nair; Pushkaran, K
A widely divergent collection of 93 groundnut varieties was screened to select the bestsuited variety for the kharif uplands and summer rice fallows. They were evaluated in preliminary trials in uplands as well as in rice fallows. The varieties exhibited wide diversity for important economic traits within and between seasons and many of them were far superior to the recommended varieties. Based on the performance in the preliminary trials, thirty one varieties including the recommended varieties (TMV 2 and TMV 7) were selected for comparative yield trials. They were tested in two seasons each in uplands and rice fallows. The varieties differed in yield and other economic traits in both seasons. The performance of the same variety, m general, varied from upland to rice fallows. TG 14 in uplands and TG 3 in rice fallows were the top ranking varieties. Spanish Improved was found to be a high yielder at both seasons. Five promising varieties were selected and they along with 3 standards were further tested in multi-locational trials at 5 locations in summer rice fallows and 6 locations in kharif uplands. The multi-locationa! trials further confirmed that TG 14 and TG 3 were the highest yielders in uplands and rice fallows respectively. Spanish Improved was also another high yielder at both seasons.
Genetic analysis in horsegram (dolichos biflorus linn.) with special reference to photoperiodic response
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2001) Sreenivasan, E; Pushkaran, K
A study was undertaken in the Department of Plant Breeding & Genetics of College of Horticulture, Vellanikkara, during 1993-2000 entitled "Genetic analysis in horsegram (Dolichos biflorus Lin.) with special reference to photoperiodic response" The main objectives were to identify stable, high-yielding, day-neutral • horsegram genotypes suitable for year-round cultivation and to understand the nature of gene action involved in the inheritance of photoperiodic response in the crop. The material consisted of 115 horsegram genotypes. Evaluation of the genotypes during rabi (traditional)indicated that enough variability exists among the genotypes with respect to seed yield and yield attributes. Studies on correlation and cause-effect relations among seed yield and yield attributes revealed that pod yield, . harvest index and haulms yield were the traits having maximum positive association and positive direct effect on seed yield. Duration to flowering or maturity did not have significant correlation with seed yield. Hence it is possible to have varieties that combine high yield and early maturity. Based on genetic diversity, the 115 genotypes were grouped into ten clusters, using Mahalanobis D2 statistics. It was found that genetic diversity existing among genotypes is not associated with their geographical origin. A selection index constructed based on seed yield, pod yield and harvest index was found to give 79.47 per cent gain in efficiency over selection based on yield alone. Genotypes selected on the basis of the preliminary evaluation were further tested over two seasons (rabi and summer) for three years (1997,1998 and 1999) in a comparative yield trial, to select best genotypes suitable for each seasons. The study revealed that the day-neutral genotype AK-42, is ideal for year-round cultivation. However, for cultivation during rabi, the photosensitive variety PHG-9 was found to be better. In general, performance of genotypes was better during rabi than III summer. Hybridisation studies between day-neutral and photosensitive types, also was taken up in order to assess the combining ability and gene action involved and for estimation of heterosis. The diallel analysis revealed that the parents AK-42 and AK- 26 (both day-neutral types ) had maximum positive general combining ability for seed yield. Highest specific combining ability for the trait was observed for the cross PHML-64 x AK-42. Relative heterosis also was observed to maximum for the same cross. Higher gca expressed by traits like days to flowering, seeds per pod and pod length indicated that these traits are controlled by additive gene action. Higher sea was observed for plant height, hundred seed weight, seed yield and pod yield, indicating that non-additive gene action play a major role in expression of these traits. The results of F2 evaluation revealed that photoperiodic response in horsegram is probably a qualitative trait, controlled by at least two genes, either in complimentary gene action or inhibitory gene action. In the case of inheritance of seed colour, the black seed colour was observed to be dominant over brown. Two genes in polymeric gene action, were found to control seed colour.
Genetic parameters for groundnut in summer rice fallows
(Kerala Agricultural University, 1991) Pushkaran, K; Gopinathan Nair, V
Genetic parameters for 15 metric characters in 80 divergent varieties of groundnut grown in the summer rice fallows were estimated. The varieties differed significantly in respect of all the characters. The pcv was higher than gcv for all the characters. High estimates of gcv, heritability and genetic advance were obtained for number of branches, flowers and leaves, spread of flowering and 100 pod weight whereas the values were low for fresh weight of pods and dry pod yield. So also the high pcv for dry pod yield suggests that the genetic improvement for the economic trait through selection for summer rice fallows is meagre. Oil content, shelling percentage and duration up to flowering and maturity registered high heritability, but low genetic advance.
Genetic resources utilisation and biometric analysis in groundnut (Arachis hypogaea L.)
(Department of Plant Breeding, College of Agriculture, Vellayani, 1983) Pushkaran, K; Gopinathan Nair, V
Maximising the production, of vegetable oils in the country is one of the badly felt national needs for which the improvement in the productivity of groundnut, the major oilseed crop of the country, deserves the best attention. As a crop, groundnut has wide adaptability and a number of other favourable attributes. Breeding improved varieties suited to the two major areas of groundnut cultivation viz, the traditional uplands during kharif land the non-traditional, but potential rice fallows during summer is an immediate necessity for popularising the crop in this State. Germplasm collection, evaluation and utilisation constitute the basic approaches in the genetic improvement of any crop. Hence this investigation. Eighty eight divergent varieties of groundnut were collected from different sources and subjected to preliminary evaluation in uplands during kharif. Ninety three varieties were evaluated in rice fallows during summer. These varieties showed wide variability in general performance, yield and other attributes within and between the situations. AH-6915 in uplands and TG-3 in rice fallows were the highest yielders. Several varieties were better in yield than the recommended varieties, viz., TMV-2 and TMV-7. A few varieties such as TG-14 end Spanish Improved were consistently superior at both' the situations.
Heterosis breeding and in vitro mutagenesis in pineapple(ananas comosus[L] merr.)
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2004) Kuriakose, K P; Pushkaran, K
Induction of polyploidy in kacholam
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 1996) Ajithmohan, N K; Pushkaran, K
A trial on induction of polyploidy in Kaempferia galanga L. was undertaken at the Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, during the period 1994-'95. A local selection Vellanikkara collected from the genetic stock maintained at AICRP on M & AP was used for the study. The objective was to create variability in kacholam by developing polyploids. The rhizomes of the crop were treated with colchicine for inducing polyploidy. Five concentration of colchicine viz., 0.05, 0.15, 0.25, 0.35 and 0.45 per cent (C2 to C6, C1 being control i.e., 0%) was tried for two time durations viz., four hours and six hours (T1 and T2), the same treatment being repeated on two consecutive days. Two methods of treatment were tried the first (M1) being chemical application in a hole drilled close to the sprouting bud and the second (M2) being the ordinary cotton swab method. Rhizomes with two different stages of bud sprouting were used: (1) with just emerging buds (S1) and (2) buds at an advanced stage of sprouting (S2). The treated rhizomes were planted in the field and their growth was examined. In the end of the crop season, 18 variant plants were identified and they were put to detailed morphological and cytological study in the next growing season. Mitotic study of the parent material confirmed that the chromosome number of kacholam is 55. Of the 18 variants identified one was found to contain 110 chromosomes in the somatic cells. As kacholam is proposed to be a pentaploid the induced polyploid must be a decaploid. The polyploid was obtained from the treatment combination S1M1T1C6. It was characterised by small plant size and reduced vigour. The leaves were thick with reduced size. Stomatal size increased conspicuously with their numbers reduced. The rhizome development was found retarded and the per plant yield was also less. The rhizome morphology was on par with the normal plants. The plant flowered neither in the first season nor in the second. In addition to the polyploid, there other stable variants were obtained from the experiment. They were also characterised by reduced vigour and yield.
Path analysis in groundnut
(Kerala Agricultural University, 1989) Pushkaran, K; Gopinathan Nair, V
Eighty groundnut varieties were raised in a randomised block design with three replications in upland during kharif. Pod yield and 17 characters were studied. Correlation coefficients at the genotypic and phenotypic levels were computed between pod yield and other characters and among themselves. Path analysis for dry pod yield was done considering eight important component characters. Dry pod yield was highly correlated positively with fresh weight of pods, haulms yield, number of mature pods, number of immature pods, duration upto maturity and 100 pod weight at the genotypic level. Negative significant correlation was seen for pod yield with plant height at the 50th day, height of main shoot and length of top. Fresh weight of pods had the highest positive direct effect followed by 100 pod weight, haulms yield and number of mature pods whereas length of top, number of flowers, number of basal primary branches and number of leaves exerted negative direct effect to dry pod yield in that order.
Screening rice varieties for deep water situation through the study of seedling growth habit under submerged conditions
(Kerala Agricultural University, 1981) Pushkaran, K; Balakrishna Rao, M J
Some successful crosses in pineapple
(Kerala Agricultural University, 1994) Radha, T; Pushkaran, K; Jacob John, P
Standardisation of selection criteria for cocoa hybrids
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 1998) Raji Varghese; Pushkaran, K
Investigation on standardisation of selection criteria for cocoa hybrids was conducted at Cadbury-KAU Co-operative cocoa Research Project (CC RP) Farm of Kerala Agricultural University, Vellanikkara during 1994-96. Twenty nine hybrids grown under Progeny Trial I and their 18 parents maintained in CYT-I were used for the study. The influence of seedling height and girth on yield was more pronounced in the case of seedlings one year after sowing than with those of 4 mas, 5 mas and 6 mas. The vegetative vigour measured by the height and diameter of trunk was found to be better correlated with precocity. The correlation coefficients of pod characters viz., length, width and weight of pods, number of beans, wet bean weight and pericarp thickness and seed characters viz., length, width, thickness and dryweight worked out between hybrids and female parents showed significant relationship in the case of pod length (r = 0.649) and number of beans (r = 0.606). But with mid parental value, the hybrids showed high correlation for the characters pod length, pod weight, number of beans, seed length, seed width and seed thickness (0.65, 0.45, 0.86, 0.70, 0.76 and 0.70 respectively). Heritability estimated by regressing offspring on female parent was high for the characters pod width, seed length and seed width (0,7, 0.64 and 0.78 respectively). Among the 29 hybrids studied, the hybrid H-4 of the cross GI 10.3 x GVI 54 was found to be promising in terms of both pod and wet bean yield. With the seedling characters of hybrids taken one year after sowing, a multiple regression equation for wet bean yield was fitted as: Y = 43 + 0.195 x1 + 3.70 X2 Where, x1 and X2 are height and girth of one year old seedlings respectively. This can be taken as a seedling selection criteria for cocoa hybrids.
Viable mutations inducted by gamma rays in groundnut
(Kerala Agricultural University, 1988) Pushkaran, K; Gopinathan Nair, V
The effects of gamma radiation at three doses (20, 30 and 40 krad) were studied in three selected genotypes of groundnut viz., Spanish Improved, TG 14 and TMV 2 with the prime objective of evolving early mutants. Observations on seed germination, seedling survival, plant height, pollen fertility and other effects ware made. Chlorophyll mutation frequency, mutant spectrum, rnutagenic effectiveness and efficiency were worked out. Germination of seeds was reduced by gamma rays and a progressive decline in germination with increasing doses was noticed. The survival was also reduced in all the genotypes and the relationship between the percentage of survival and doses of radiations was inverse. A reduction in plant height was noticed in tha three genotypes on the 30th day. Pollen fertility deceased with increasing doses. The frequency of chlorophyll mutations increased with increasing doses of gamma rays in all the genotypes; the maximum baing for TG 14. Albina; xantha, chlorina and viridis were the chlorophyll mutants observed, of which viridis was seen the most frequent. No definite relationship was seen in any of the genotypes between doses of radiation and mutagenic effectiveness. In TMV 2 and Spanish Improved, effectiveness was the maximum at the highest dose of radiation tried (40 krad) while in TG 14, it was at tha intermediate dose (30 krad). Mutagenic efficiency, too, did not show ony specific relationship with the radiation doses in the g¬ypes. TMV 2 and TG 14 at 20 krad and Spanish Improved at 40 krad recorded the maximum mutagenic efficiency based on lethality. Based on injury and sterility, the highest efficiency was noted at 40 krad and 20 krad in TMV 2 and Spanish Improved respectively and both at 30 krad in TG 14. A wide range of viable mutants was isolated in the M3 generation affecting almost all the characters including early mutants of great practical utility. Macromutants with simultaneous change in a constellation of characters were isolated.