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Kerala Agricultural University, Thrissur

The history of agricultural education in Kerala can be traced back to the year 1896 when a scheme was evolved in the erstwhile Travancore State to train a few young men in scientific agriculture at the Demonstration Farm, Karamana, Thiruvananthapuram, presently, the Cropping Systems Research Centre under Kerala Agricultural University. Agriculture was introduced as an optional subject in the middle school classes in the State in 1922 when an Agricultural Middle School was started at Aluva, Ernakulam District. The popularity and usefulness of this school led to the starting of similar institutions at Kottarakkara and Konni in 1928 and 1931 respectively. Agriculture was later introduced as an optional subject for Intermediate Course in 1953. In 1955, the erstwhile Government of Travancore-Cochin started the Agricultural College and Research Institute at Vellayani, Thiruvananthapuram and the College of Veterinary and Animal Sciences at Mannuthy, Thrissur for imparting higher education in agricultural and veterinary sciences, respectively. These institutions were brought under the direct administrative control of the Department of Agriculture and the Department of Animal Husbandry, respectively. With the formation of Kerala State in 1956, these two colleges were affiliated to the University of Kerala. The post-graduate programmes leading to M.Sc. (Ag), M.V.Sc. and Ph.D. degrees were started in 1961, 1962 and 1965 respectively. On the recommendation of the Second National Education Commission (1964-66) headed by Dr. D.S. Kothari, the then Chairman of the University Grants Commission, one Agricultural University in each State was established. The State Agricultural Universities (SAUs) were established in India as an integral part of the National Agricultural Research System to give the much needed impetus to Agriculture Education and Research in the Country. As a result the Kerala Agricultural University (KAU) was established on 24th February 1971 by virtue of the Act 33 of 1971 and started functioning on 1st February 1972. The Kerala Agricultural University is the 15th in the series of the SAUs. In accordance with the provisions of KAU Act of 1971, the Agricultural College and Research Institute at Vellayani, and the College of Veterinary and Animal Sciences, Mannuthy, were brought under the Kerala Agricultural University. In addition, twenty one agricultural and animal husbandry research stations were also transferred to the KAU for taking up research and extension programmes on various crops, animals, birds, etc. During 2011, Kerala Agricultural University was trifurcated into Kerala Veterinary and Animal Sciences University (KVASU), Kerala University of Fisheries and Ocean Studies (KUFOS) and Kerala Agricultural University (KAU). Now the University has seven colleges (four Agriculture, one Agricultural Engineering, one Forestry, one Co-operation Banking & Management), six RARSs, seven KVKs, 15 Research Stations and 16 Research and Extension Units under the faculties of Agriculture, Agricultural Engineering and Forestry. In addition, one Academy on Climate Change Adaptation and one Institute of Agricultural Technology offering M.Sc. (Integrated) Climate Change Adaptation and Diploma in Agricultural Sciences respectively are also functioning in Kerala Agricultural University.

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  • ThesisItemOpen Access
    Diallel analysis in rice bean(Vigna umbellata( Thunb.) ohwi & ohashi)
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 1999) Preeti, S V; KAU; Radha Devi, D S
    A diallel analysis in ricebean (Vigna umbellata (Thunb.) Ohwi and Ohashi) was carried out in the Department of Plant Breeding and Genetics, during 1997 - '98. The experimental material consisted of six parental lines and 30 F I hybrids, laid out in Randomised Block Design with three replications. The six parents were 3 LG, 5 LG, 6 LG, 8 LG, 9 LG, and 100 LG obtained from the germ plasm collection maintained at NBPGR, Thrissur. The observations were recorded on yield and yield attributing characters. Significant differences were detected among the mean performance of the genotypes, for all the characters studied. The combining ability analysis carried out by Method I, Model I of Griffing's approach (1956), revealed that the parent, 8LG was the best general combiner for most of the yield attributing traits. Among the crosses, 8LG x 3 LG exhibited outstanding sea for seed yield per plant. The crosses involving 8 LG were found to be good specific combiners. The combinations involving 3 LG and 6 LG also gave good specific combining ability effects. The numerical analysis by Hayman's approach indicated overdominance for almost all characters, which was confirmed by graphical analysis. The dominance of decreasing alleles in the parents was indicated by the negative value of F for all characters except, plant height, length of pods and number of seeds per pod. An almost equal distribution of genes with positive and negative effects was indicated by the ratio of H2 to 4H} for all the characters. The regression coefficient of covarince between parents and their offsprings in each array (Wr) on variance of all progenies in each parental array (Vr) did not- differ from unity, for plant height, length of pods, seed yield, 100 seed weight, days to maturity and protein content, indicating that assumption of non-allelic interaction was satisfactory for these characters. The Vr - Wr graph indicated that the parents were genetically divergent for days to first flowering, number of pods per plant, number of seeds per pod, 100 seed weight, days to maturity, root weight and nodule weight. Manifestation of heterosis was seen for all the characters studied. Among the hybrids, 8 LG x 3 LG was the most outstanding for yield and yield related characters. The crosses, 8 LG x 9 LG, 8 LG x 100 LG, 6 LG x 9 LG, 100 LG x 8 LG and 6 LG x 3 LG also performed better in yield and yield attributing characters. In general, hybrids involving 8 LG and 6 LG were found to be heterotic.
  • ThesisItemOpen Access
    Combining ability in vegetable cowpea
    (Department of Plant Breeding, College of Agriculture, Vellayani, 1992) Rejatha, V; KAU; Ramachandra Nair, N
    A 6 x 6 diallel analysis was conducted at the Department of Plant Breeding, College of Agriculture, Vellayani, during 1990, aimed at analysing the combining ability, gene action and heterosis of six vegetable cowpea (Vigna unguiculata var-sesquipedalis) lines collected from the germplasm maintained in this department. The experiment I consisted of crossing the six parental lines in all possible combinations, without reciprocals. The material for experiment II consisted of the six parental lines and fifteen hybrids. They were grown in a Randomised Block Design with three replications.The combining ability analysis was carried out based on method 2 under model I as suggested by Griffing (1956). The treatments showed significant differences in most of characters except number of pods/plant and fruit yield/plant. The variance due to general combining ability was significant and higher in magnitude than specific combining ability for the characters days to flowering, mean weight of pod, mean length of pod, number of seeds/pod, length of internode and seed/pod ratio. It was found that the parent selection 104 and selection 145 were the best general combiners for most of the characters studied. The parent selection 129 was the best general combiner for earliness. The hybrids selection 145 x selection 129 was the best specific combiner for mean weight of pod and number of seeds/pod. The hybrid selection 145 x kurutholapayar was the best specific combiner for earliness. The significance of g.c.a. and s.c.a. variances for most of characters indicate the importance of additive and non-additive gene action in controlling the inheritance of these characters. But additive gene action played a major role suggesting that improvement could be made through selection. Heterosis was calculated over mid and better parental values. Maximum positive heterosis was found for the character fruit yield/plant. Since considerable heterosis was evident in most of the characters, heterosis breeding can be attempted in cowpea
  • ThesisItemOpen Access
    Genetics of shattering resistance in rice (Oryza sativa L.)
    (Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2020) Akhil, K P; KAU; Biju, S
    Rice is the staple food crop of Kerala. Among the plethora of rice varieties available Jyothi is by far the most popular in the state owing to its consumer preference. Easy seed shattering leads to significant loss in Jyothi which can be overcome by transferring shattering resistance to it. Screening of genotypes for shattering resistance identified donors like Athira and Triveni with good combining ability. The present experiment was thus envisaged to transfer shattering resistance to Jyothi from the donors and to study the nature of inheritance of seed shattering trait using six parameter model of generation mean analysis. Observations were recorded in the two crosses viz., Jyothi x Aathira and Jyothi x Triveni for eleven quantitative characters viz. days to 50 per cent flowering, plant height, tillers per plant, panicles per plant, panicle length, spikelets per panicle, seeds per panicle, days to maturity, test weight, grain yield per plant and shattering per cent in six generation (P1, P2, F1, F2, B1 and B2) obtained from the two crosses. Panicle per plant, test weight, grain yield per plant and shattering per cent recorded significant heterosis in the desirable direction in both the crosses. Mean effect (m) was significant and positive for all the characters studied in both the crosses. The additive component (d) was significant and positive for days to 50 per cent flowering, tillers per plant, panicles per plant, days to maturity, grain yield per plant and shattering per cent in the cross Jyothi x Triveni while the other characters recorded significant and negative additive gene effect. The characters tillers per plant, test weight and shattering per cent showed significant positive additive gene effect in the cross Jyothi x Aathira and rest of the characters showed significant and negative additive component. Dominance gene effect was observed to be significant and negative for most of the characters studied in both the crosses. Non-allelic interactions were observed to be significant in most of the characters except days to 50 per cent flowering, tillers per plant, days to maturity and shattering per cent in the cross Jyothi x Aathira. The epistatic interaction model of generation mean analysis was found adequate for obtaining gene actions for all the characters. Among the three type of interactions dominance x dominance interaction was found to be more important for all the characters. Additive x additive and additive x dominance gene interactions were found to be equally important for most of the characters studied in both the crosses. Dominance gene effect was observed controlling the genetic variance in most of the traits studied. Presence of additive and non-additive along with epistatic interaction revealed the complex nature of inheritance of the characters. Predominant dominant gene effect along with duplicate epistasis limits the scope of direct selection. In the F2 populations characters showed high heritability in both the populations studied. Plant height, panicle length and days to maturity were found to have low genetic advance. Plant height recorded moderate genetic advance, whereas, other characters exhibited high genetic advance in F2 population derived from the cross Jyothi x Triveni. Days to maturity showed low genetic advance, days to 50 per cent flowering and panicle length recorded moderate genetic advance and other characters recorded high genetic advance in F2 population derived from the cross Jyothi x Aathira. As shattering resistance is governed predominantly by additive gene effects selection in the early segregating generations will be highly rewarding. The selected lines may be advanced to further generations to identify lines with high yield coupled with shattering resistance and can be forwarded to develop high yielding varieties with low shattering or bi-parental mating among the selected lines may be undertaken to recover superior recombinants with high yield and shattering resistance.
  • ThesisItemOpen Access
    Development of doubled haploids for iron toxicity tolerance in rice (Oryza sativa L.)
    (Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2020) Chakravarthi Mari, Bastian; KAU; Dijee, Bastian
    Rice is the staple food crop of the people of Kerala. The production of rice in Kerala is impeded by many biotic and abiotic stresses. Iron toxicity is one of the major abiotic stresses of acidic soils in Kerala. The present study “Development of doubled haploids for iron toxicity tolerance in rice (Oryza sativa L.)” was taken up with the objective of developing doubled haploids with tolerance to iron toxicity through in vitro anther culture. Doubled haploids being homozygous stable lines, can be used both as immortal populations for QTL mapping as well as varieties, if suitable agronomic traits are present in them. Therefore, this study was taken up which comprised of three experiments. In experiment I, two tolerant genotypes (Swetha and Mangala Mahsuri) and two susceptible genotypes (Cul-90-03 and Cul 8709) were crossed with Tulasi. In the second experiment the parents along with their hybrids were evaluated for biometric characters and yield. The hybrids obtained from the crosses were significantly different for all the characters observed. Panicles per plant and grain yield per plant recorded highly significant and positive relative heterosis and heterobeltiosis. The anthers from the F1s produced in the previous experiment were used for anther culture studies in the third experiment. Sterilisation with various sterilants like 70 % ethanol, 0.1 % mercuric chloride, 5.25% sodium hypochlorite and their combinations were done. Explant sterilisation with 5.25% sodium hypochlorite for 5 to 20 minutes was effective in controlling contamination in the in vitro cultures. Study to know the best number of days of cold pre-treatment at 10oC was done (0, 3, 6, 9, 12, 15 days). Cold pre-treatment of anthers at 10oC for 9 days was found to be optimum for most of the genotypes studied. Two different media viz., N6 and B5 were tried with different combinations of 2,4 - D and Kn. N6 media responded better than B5 media for callus induction in all the growth hormone combinations. The effect of carbon source on callusing was studied using maltose and sucrose at various levels (30,40,50 mg/L) and it was found that maltose at 30g/L gave the best callus induction (7.95%). Among the auxins used in the present study,2,4-D was found to be better than NAA for callus induction while among cytokinins, Kinetin responded better than BAP for callus induction. The growth hormone combination 2,4- D (2mg/L) + Kn (0.5mg/L) was adjudged the best for callus induction. Additives like silver nitrate (AgNO3), casein hydrolysate (CH), yeast extract (YE), proline and activated charcoal were added to the basal media to improve callusing. when AgNO3 is applied from 0 to 1ml with 0.1 ml gradation, 0.5-0.6ml of 0.1N AgNO3 was found to be better in callus induction as well as the days to callus induction was reduced at these concentrations. 250 – 500 mg/L of CH and 250mg/L proline were found to induce significant response for callusing while activated charcoal and yeast extract did not have any considerable effect on callus induction. Hybrid H1 recorded good callus response when maltose at three levels was tried in the media (30, 40, 50g/L) whereas hybrid H2 gave uniform response at all the levels of maltose. There was significant variation among the genotypes in their response to all the factors studied. The best responses were as follows: - H1(Swetha x Tulasi) - N6+2,4-D (2mg/L) + Kn (0.5mg/L) + 30g/L maltose +0.5ml (0.1 N AgNO3) + 250mg/L proline + 250mg/L CH +2.5g/L gelrite gellan gum. H2(Mangala Mahsuri x Tulasi) - N6+2,4-D (2mg/L) +Kn (0.5mg/L) + 30g/L maltose +0.5ml (0.1N AgNO3) +250mg/L proline+250mg/L CH +2.5g/L gelrite gellan gum. H3(Cul-90-03 x Tulasi) - N6+2,4-D (2mg/L) +Kn (0.5mg/L) + 30g/L maltose + 0.5ml (AgNO3) + 250mg/L proline + 250mg/L CH + 2.5g/L gelrite gellan gum. H4(Cul 8709 x Tulasi)- B5 + 2,4-D (2mg/L) + Kn (0.5mg/L) + 30g/L maltose + 0.5ml (0.1N AgNO3) + 250mg/L proline + 250mg/L CH + 2.5g/L gelrite gellan gum. The calli obtained from the different genotypes were plated on two different callus regeneration media R1 (MS+ NAA(1mg/L) + Kn (2mg/L) + IAA (0.5mg/L) + CW (5%)) and R2 (MS+NAA (0.25mg/L) + BAP (0.75mg/L) + Kn(0.25mg/L)). There was no response in R1 media. Callus regenerated into plantlets in R2 but all the plantlets obtained were albinos leading to mortality and hence plantlet hardening and field planting could not be undertaken.
  • ThesisItemOpen Access
    Preliminary evaluation of double cross hybrids for yield and vascular streak dieback (VSD) disease resistance in cocoa (Theobroma cacao L.)
    (Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2020) Alfiya, A R.; KAU; Minimol, J S
    Cocoa is highly influenced by the climate change and growing environment, necessitating a long term and dynamic breeding programme. Even though the breeding programmes primarily focus on the development of high yielding varieties, outbreak of new pests and pathogens shift the priority to the development of resistant varieties. Vascular Streak Dieback disease (VSD) caused by Ceratobasidium theobromae (Samuels et al., 2012), pose a great threat to cocoa crop, causing complete defoliation and eventual death (Abraham et al., 2002). Even the high volume spray of chemicals was ineffective in disease control (Prior, 2007), and the only way to tackle it is to breed resistant varieties. Resistance breeding may result in yield reduction (Xu et al., 2017) however, breeding for double cross hybrids can overcome this situation (Gallais and Guy, 1971). Average yield superiority of the double cross hybrids over the F1 hybrids has been shown by many scientists (Sriani et al., 2003; Ghanwat et al., 2016). Twenty double cross hybrids, bred for vascular streak dieback disease and planted during 2017, were used for the present study. Morphological characterization of the hybrids was carried out based on the quantitative and qualitative characters. Thirteen pod characters, twelve floral characters, six bean characters and flush colour of the leaves were studied. Except colour of the petal and number of the ridges and furrows, all other characters have expressed high variability among the double cross hybrids. The double cross hybrids have exhibited significant difference for fat and polyphenol content. All the twenty double cross hybrids were screened and scored for the VSD resistance in the field condition, using the score chart (Abraham et al., 2000). Based on the disease intensity, they were classified into eleven resistant and nine partially resistant.
  • ThesisItemOpen Access
    Varietal evaluation and development of hybrids in Phalaenopsis orchids
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2020) Roshin Mariam, George.; KAU; Beena, Thomas
    The research programme entitled “Varietal evaluation and development of hybrids in Phalaenopsis orchids” was undertaken in the Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, during 2018-2020. The objective of the study was to assess the genetic variability of Phalaenopsis orchids and to improve them through intervarietal hybridization. The first experiment was varietal evaluation wherein ten genotypes of Phalaenopsis, King Car Purple Queen, Lianher Happy Song, Fullers Rabbit, Lianher Orange, Fullers, Taisuco Fire Bird x King Hisang Rose, Reyoung Gold, Jiuhbao Venus, Wang Lin Rose and Young Home Golden having good market value and cut flower qualities were evaluated in the green house using completely randomized design. The analysis of variance revealed that significant difference exists among the parental genotypes with respect to the majority of biometric characters studied. Vegetative characters such as leaf area, plant height, number of leaves and leaf width exhibited the highest estimates of variance at both genotypic and phenotypic levels. Among the floral traits, length of inflorescence, number of flowers per inflorescence, vase life, internodal length of the peduncle and days to first flower opening from inflorescence emergence showed the highest genotypic and phenotypic variances. Floral characters like length of inflorescence, flower longevity on the plant, days to first flower opening from inflorescence emergence, length of flower, width of the flower and internodal length of peduncle as well as vegetative characters like plant height, leaf width and leaf area showed high heritability. Many of the characters exhibited high genetic advance (> 20%); the highest value was observed for length of the inflorescence followed by leaf area. High heritability (>70%) combined with high genetic advance (>20%) was exhibited by majority of the characters under study like days to first flower opening from inflorescence emergence, flower longevity on the plant and vase life. The genotypic, phenotypic and environmental correlations of the ten parental genotypes were studied for eleven biometric characters. High positive correlation at genotypic and phenotypic levels was observed between most of the vegetative and floral characters studied. Highly significant positive correlations were exhibited by length of the flower with number of flowers per inflorescence, length of inflorescence with number of inflorescence and number of flowers per inflorescence with vase life. The second experiment was hybridization and compatibility analysis. Intercrossing in all possible combinations involving the three best parental genotypes of Phalaenopsis selected based on inflorescence characters was done. Jiuhbao Venus, Young Home Golden and Lianher Orange were selected for intercrossing. All nine possible combinations including three selfs, three crosses and three reciprocals were attempted. Out of the nine crosses, four combinations succeeded in producing harvestable green capsules. They are Jiuhbao Venus x Young Home Golden, Jiuhbao Venus x Lianher Orange, Young Home Golden x Jiuhbao Venus and Young Home Golden x Lianher Orange. The highest strength of incompatibility was exhibited by Lianher Orange. Germination in vitro was observed for the four combinations from which the green capsules were successfully harvested. These hybrid combinations can be utilized for further crop improvement programmes.
  • ThesisItemOpen Access
    Genetic variability studies in grain cowpea (Vigna unguiculata (L.) Walp.)
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2020) Darshana, A S.; KAU; Bindu, M R
    The study entitled “Genetic variability studies in grain cowpea (Vigna unguiculata (L.) Walp.) was carried out at Farming Systems Research station, Sadanandapuram during December, 2019 – March, 2020 with the objective to evaluate and select shade tolerant grain cowpea genotypes suited to the coconut based homesteads. The 33 grain cowpea genotypes collected from research stations under KAU, AICRP centre and agricultural universities of different states were evaluated in coconut based homestead garden where coconuts are of age 30 – 40 years, in randomized block design replicated thrice. The seeds were sown on raised beds of (3 х 1.5) m2 size at a spacing of 30 cm х 15 cm and cultural operations and plant protection measures were adopted as per the “Package of Practices Recommendations: Crops 2016” of Kerala Agricultural University. The average light intensity in the experimental field recorded was 0.719 W/m2 resulting in shade of 33.49 per cent. The genotypes were evaluated for biometric and physiological characters associated with shade tolerance and quality character of seed. The genotypes showed significant differences for all the characters studied. Genetic parameter analysis was performed for twelve characters and for all the characters PCV values were higher than GCV values indicating the influence of environment. The phenotypic and genotypic coefficients of variation were maximum for seed yield per plant and minimum for protein content. Heritability was high for all the twelve characters and genetic gain was high for all the characters except days to 50% flowering and protein content. The correlation studies revealed positive correlation of the characters days to 50% flowering, number of pods per plant, number of seeds per pod, crop duration, harvest index, LAD at flowering, CGR at flowering and protein content with seed yield. The path analysis provides information on contribution of traits by partitioning the total correlation into direct and indirect effects. Path analysis of the eight characters showing significant correlation with seed yield revealed high positive direct effect of the characters number of pods per plant and harvest index on seed yield. High indirect effect on seed yield was observed for CGR at flowering through number of pods per plant. Cluster analysis aids in the selection of genetically divergent parents for hybridization programme which results in greater heterosis. Cluster analysis using Mahanalobis D2 statistic following Tocher’s method grouped the 33 genotypes into nine clusters. Cluster II with 10 genotypes was the largest followed by cluster I and cluster V (8 genotypes each), cluster III (2 genotypes) and clusters IV, VI, VII, VIII, IX which were solitary clusters. Highest intra cluster distance was recorded among the genotypes of cluster V and lowest in cluster III whereas highest inter cluster distance was observed between the genotypes of the clusters III and IX followed by clusters VI and IX. The present study revealed that the variety Sreya recorded highest seed yield under partially shaded condition. The genotypes CHESCP-03, CHESCP-17 and CHESCP-32 are medium in duration with shade tolerance and higher yield, hence suited to the coconut based homesteads. Among the early duration types, Subhra recorded the highest yield. Genotypes CHESCP-19 and KYLMVU-6 recorded yield on par with the shade tolerant genotypes CHESCP-03, CHESCP-17 and CHESCP-32. Subhra and the late duration varieties Sreya, CHESCP-19 and KYLMVU-6 recorded low values for shade tolerant parameters and there is scope for improving the yield by hybridization with shade tolerant varieties. Subhra and CHESCP-21 were found to be superior for protein content. As quality of a pulse variety is determined by the protein content, these genotypes can be used as parents in quality improvement programmes. The superior genotypes identified in the study can be recommended for cultivation and future breeding programs.
  • ThesisItemOpen Access
    Genetic analysis in fodder rice bean (Vigna umbellata (Thunb.) for yield and quality
    (Department of Plant Breeding and Genetics, College of Agriculture, Vellayani, 2020) Bhoomika, B K; KAU; Mareen, Abraham
    Rice bean is an underutilized fodder legume, belonging to family Fabaceae, having chromosome number 2n=22. It is emerging as a potential nutritious high yielding animal fodder with no major pest and disease incidence and demands no fertilizer and little special care during growth. In India and Nepal it is mainly grown in two seasons February and March for harvest during summer and in July and August for harvest during December. It can be grown as sole crop or inter crop with maize and sorghum. The present investigation „Genetic analysis in fodder rice bean (Vigna umbellata (Thunb.) for yield and quality‟ was conducted at Department of Plant Breeding and Genetics, College of Agriculture, Vellayani. 30 genotypes of rice bean collected from NBPGR were evaluated in Randomized Block Design with three replications. The crop was harvested at 50% flowering stage. Observations were recorded for various qualitative and quantitative characters, viz. days to first flowering, days to 50% flowering, plant height, number of branches, number of leaves, leaf fresh weight, stem fresh weight, green fodder yield, leaf dry weight, stem dry weight, dry fodder yield, leaf area index, leaf stem ratio, production efficiency, crude protein, crude fiber and dry matter production. Various statistical tools such as analysis of variance, genotypic coefficient of variation (PCV), phenotypic coefficient of variation (GCV), heritability, genetic advance, correlation studies, path analysis and cluster analysis were carried out to find out extent of variation present in existing genotypes. Analysis of variance was found to be significant for all the characters except for the character days to 50% flowering. This reveals the presence of variability among the genotypes and hence selection can be effective in the population. The genotype IC341991 recorded maximum leaf fresh weight (17.41 t ha-1), stem fresh weight (21.87 t ha-1), green fodder yield (35.49 t ha-1), leaf dry weight (2.5 t ha-1), stem dry weight (3.82 t ha-1) and dry fodder yield (6.46 t ha-1), which was on par with the genotypes IC341986 and IC521350. Minimum green fodder yield was recorded by the genotypes EC98452 (22.32 t ha-1) IC341998 (23.25 t ha-1) EC16136 (24.12 t ha-1). Maximum Crude protein content was recorded for the genotypes IC521119 (21.0%), IC521152 (20.27%) and IC521115 (19.74%) while minimum crude protein content was reported for the genotype IC18553 (13.30%). Crude fibre content was found to be high for the genotype IC469192 (6.7%) and lowest crude fibre content was recorded for the genotype EC98452 (2.8%). The parameters of genetic variability such as genotypic coefficient of variation (GCV), phenotypic coefficient of variation (PCV). Heritability (H2) and Genetic Advance (GA) were carried out to find genetic variability present in the genotypes. All PCV values were highest then the GCV values, indicating least influence of environment on the expression of characters. Maximum PCV and GCV were observed for the characters crude fibre and dry fodder yield. High heritability coupled with high genetic advance was reported for the characters dry matter production, crude fibre, leaf area index, crude protein and dry fodder yield. High heritability and genetic advance indicates presence of additive gene action and hence selection of these characters will be rewarding. Correlation studies gives information about degree and magnitude of relationship between two or more variables. Green fodder yield showed significant positive correlation with number of leaves, stem fresh weight, production efficiency, stem dry weight, leaf area index, dry fodder yield, leaf fresh weight, dry matter production, number of branches, plant height, leaf dry weight, crude fibre and leaf stem ratio. Path analysis is a multiple regression statistical analysis which partitions the correlation coefficients into measures of direct and indirect effect. path analysis revealed that characters production efficiency, leaf dry weight, plant height, number of leaves, crude protein, leaf fresh weight, leaf stem ratio and number branches showed direct positive effect on green fodder yield. Cluster analysis was carried out to know the extent of genetic diversity present in the population. Based on D2 statistics 30 genotypes of rice bean were grouped into 5 clusters following Tocher‟s method luster I being the largest cluster contains 12 genotypes followed by cluster III (10 genotypes), cluster IV (4 genotypes), cluster III (3 genotypes) and cluster V (1 genotype). Highest intra cluster distance was observed in the genotypes falling under the cluster III followed by IV and II. Maximum inter cluster distance was observed in the genotypes falling under the cluster III and V, followed by II and III and I and V. Genotypes should be selected from the clusters which shows highest divergence for the success of breeding program. The study revealed presence of ample amount of variability among the genotypes for all the characters studied. The genotype IC341991was found to be superior in terms of yield and yield attributing characters followed by genotypes IC341986, IC521350 and IC521134. These superior genotypes can be forwarded for further trials for variety development or can be used as parents for future breeding work.
  • ThesisItemOpen Access
    Induction of polyploidy in kacholam
    (Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 1996) Ajithmohan, N K; KAU; 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.