Browsing by Author "Sreenivasan, E"

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Correlation and path coefficient analysis in guinea grass (Panicum maximum Jacq.)
(Department of Agricultural Botany, College of Agriculture, Vellayani, 1983) Sreenivasan, E; Kamalam, N
A study was undertaken at the Department of Agricultural Botany, College of Agriculture, Vellayani, to determine the character association for yield and quality of green fodder and their degree of association and relative influence on yield in guinea grass. Twenty four diverse varieties of guinea grass were selected for the study and laid out in randomised block design with three replications. Observations were made on nine morphological characters and four chemical attributes and the data collected were subjected to variability studies and correlation analysis. Five morphological characters which showed highly significant genotypic correlation with green fodder yield were considered for path coefficient analysis in order to separate the total correlation of these characters with green fodder yield into direct effects and indirect effects via. other characters.
Effect of phosphorus and sulphur on growth, yield and nutrient uptake of rainfed upland cowpea
(Kerala Agricultural University, 1998) Gracy Mathew; Sreenivasan, E; Anilakumar, K
A field experiment was conducted during kharif 1992-94 in a sandy loam acid laterite soil to study the effect of graded doses of phosphorus and sulphur on the yield and nutrient uptake of rainfed cowpea (Vigna unguiculata [L.j Walp). The different levels of phosphorus showed significant difference in the yield and nutrient uptake of cowpea. Maximum grain yield and nutrient uptake was obtained with application of 60 kg P3O5 ha'1. The net return was also highest with this level of phosphorus nutrition. Application of sulphur did not show any remarkable influence on growth, yield and nutrient uptake of cowpea.
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 analysis of segregating generations for yield attributes and resistance to fruit and shoot borer (Earias vittella Fab.) in bhindi(Abelmoschus spp.)
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2008) Divya Balakrishnan; Sreenivasan, E
The research study entitled “Genetic analysis for yield attributes and resistance to shoot and fruit borer (Earias Vittella Fab.) in Bhindi (Abelmoschus spp.)” was undertaken during the period 2006-2008 at Department of plant Breeding and Genetics, College of Horticulture, Kerala Agricultural University, Vellanikkara, Thrissur. The main objectives of this project were to study the nature of gene action governing fruit and shoot borer resistance and yield attributes and to attempt for transfer of shoot and fruit borer resistance to genotypes with desirable yield attributes. Six diverse okra genotypes viz, three high yielding Arka Anamika, Salkeerthy (both A.esculentus type) and Susthira (A. caillei type) as well as three resistant genotypes KL9, Sel 2(both A.esculentus type) and AC5 (A. caillei type) were crossed in a 6 x 6 complete diallel pattern. Thirty crosses were made out of which 24 F1s were fertile and six interspecific crosses were sterile. Fifteen selected F2s were evaluated for yield attributes and resistance to fruit and shoot borer. High genetic variability, heritability and genetic gain were observed in fruit weight and plant height. Both F1 and F2 of the cross Arka Anamika x Salkeerthy recorded the higher fruit yield than others. Arka Anamika was found to be a good general combiner for fruit number, fruit weight and fruit length. KL9 showed high gca for days to first flowering, internodal number and fruit weight. Fruit yield was positively associated with number of fruits, number of internodes, fruit weight and fruit length. Shoot and fruit borer infestation recorded negative association with plant height, flowering period, fruit number, fruit yield and internodal length. Overdominance was observed for most of the yield contributing traits. Generation mean analysis for six generations from two crosses viz. Sel 2 x AC 5 and KL 9 x Salkeerthy were carried out and gene action for yield attributes and resistance to fruit and shoot were studied. Duplicate non allelic interactions were observed for most of the traits studied. Complementary epistasis govern the inheritance of fruit borer resistance in the cross Sel 2 x AC 5. Digenic non-allelic interaction model was found inadequate to explain shoot borer infestation. Biochemical analysis revealed the presence of higher levels of phenol and tannin content in fruits and shoots of resistant genotypes. The F1 of the cross Sel 2 x AC 5 was identified as the best hybrid for both marketable fruit yield and resistance to fruit and shoot borer and it also showed field resistance to Yellow Vein Mosaic Virus.
Genetic analysis of segregating generations for yield attributesand resistance to fruit and shoot borer (Earias vittella Fab.) in bhindi (Abelmoschus spp.)
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2008) Divya Balakrishnan; Sreenivasan, E
The research study entitled “Genetic analysis for yield attributes and resistance to shoot and fruit borer (Earias Vittella Fab.) in Bhindi (Abelmoschus spp.)” was undertaken during the period 2006-2008 at Department of plant Breeding and Genetics, College of Horticulture, Kerala Agricultural University, Vellanikkara, Thrissur. The main objectives of this project were to study the nature of gene action governing fruit and shoot borer resistance and yield attributes and to attempt for transfer of shoot and fruit borer resistance to genotypes with desirable yield attributes. Six diverse okra genotypes viz, Arka Anamika, KL9, Salkeerthy, Sel 2, Susthira and AC5 were crossed in a 6 x 6 complete diallel pattern. Thirty crosses were made out of which 24 Fjs were fertile and six interspecific crosses were sterile. Fifteen selected F2S were evaluated for yield attributes and resistance to fruit and shoot borer. High genetic variability, heritability and genetic gain were observed in fruit weight and plant height. Both Fi and F2 of the cross Arka Anamika x Salkeerthy recorded the higher fruit yield than others. Arka Anamika was found to be a good general combiner for fruit number, fruit weight and fruit length. KL9 showed high gca for days to first flowering, intemodal number and fruit weight. Fruit yield was positively associated with number of fruits, number of intemodes, fruit weight and fruit length. Shoot and fruit borer infestation recorded- negative association with plant height, flowering period, fruit number, fruit yield and intemodal length. Overdominance was observed for most of the yield contributing traits. Generation mean analysis for six generations from two crosses viz. Sel 2 x AC 5 and KL 9 x Salkeerthy were carried out and gene action for yield attributes and resistance to fruit and shoot were studied. Duplicate non allelic interactions were observed for most of the traits studied. Complementary epistasis govern the inheritance of fruit borer resistance in the cross Sel 2 x AC 5. Digenic non-allelic interaction model was found inadequate to explain shoot borer infestation. Biochemical analysis indicated the presence of higher levels of phenol and tannin content in fruits and shoots of resistant genotypes. The Fi of the cross Sel 2 x AC 5 was identified as the best hybrid for both marketable fruit yield and resistance to fruit and shoot borer and it also showed field resistance to Yellow Vein Mosaic Virus.
In vitro propagation in ashoka (Saraca asoca (Roxb) de Wilde)
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2011) Brindha Devi, I; Sreenivasan, E
Invitro propagation in ashoka : saraca asoca (Roxb.) de wilde.
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2011) Brindha Devi, I; Sreenivasan, E
Path analysis in guinea grass (Panicum maximum jacq.)
(Kerala Agricultural University, 1986) Sreenivasan, E; Kamalam, N; Nayar, N K
Twenty four diverse genotypes of guinea grass were assessed to test the path coefficient relation to fix the characters having maximum influence on fodder yield. Path analysis revealed that the maximum direct contribution to fodder yield was through plant height followed by girth of internode. Number of days to 50 per cent flowering, girth of internode and length of panicle also showed indirect contributions towards higher yield. It was also clear from the present investigation that a positive selection can be achieved based on plant height and culm thickness »B tfas fodder crop.