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ThesisItem Open Access Genetic variability, path analysis and stability parameters in sesame(Department of Plant Breeding, College of Agriculture, Vellayani, 1985) Sverup, John; KAU; Gopinathan Nair, VBiometric analysis in a varietal collection of sesame was undertaken to study the genetic variability, correlations, path analysis and stability parameters. One hundred sesame types were evaluated in replicated trials at Vellayani in uplands during rabi and at Kayamkulam in rice fallows during summer. Genetic variability and correlations were estimated and path analysis worked out independently as both the locations. Location trials for estimating stability parameters were conducted at three places viz. in uplands during rabi at Pattambi and Vellayani and in rice fallows during summer at Kayamkulam. Large values for genotypic coefficients of variation were obtained for characters such as number of capsules on branches, number of capsules perplant, number of capsules on main stem and number of branches during rabi as well as summer. The lowest genotypic coefficient of variation was obtained for number of days to maturity during both rabi and summer. High values of heritability were recorded by seed protein content , seed oil content, height upto first capsule and weight of 1000 seeds under both conditions.ThesisItem Open 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 SA 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.ThesisItem Open Access Combining ability in vegetable cowpea(Department of Plant Breeding, College of Agriculture, Vellayani, 1992) Rejatha, V; KAU; Ramachandra Nair, NA 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 cowpeaThesisItem Open Access Characterization and identification of black pepper accessions (Piper nigrum L.) for stress tolerance and quality(Department of plant breeding, College of Horticulture, Vellanikkara, 2019) Prakash, K M; KAU; Jiji, JosephBlack pepper (Piper nigrum L.), often described as the ‘King of spices’ is the most important spice crop, grown for its berries in the world. Indian pepper is preferred across the globe due to its intrinsic qualities. Foot rot is a devastating disease of black pepper. In the changing climate, drought can be a major threat in black pepper production. Hence, the present study was taken up at College of Horticulture, Vellanikkara and ICAR-IISR, Kozhikode to characterise and to identify superior accessions of black pepper for yield, quality and tolerance to biotic and abiotic stresses. Fifty accessions of black pepper in the bearing stage maintained in the National Active Germplasm Site of ICAR-IISR, Kozhikode formed the base material for the study. The accessions were characterised for fifty qualitative and fifty quantitative characters following the descriptor developed by IPGRI (1995). Wide variability was observed among the accessions for ten qualitative characters. Quantitative characters of shoot, leaf, spike and fruit also showed wide variability. Field tolerance to foot rot disease and pollu beetle infestation was observed among the accessions. Twenty accessions were selected from the base collection based on superiority of yield (> 450g green berries/vine) , field tolerance to foot rot disease infection (biotic susceptibility score 1) and pollu beetle infestation (biotic susceptibility score 1-3). They were further evaluated for biochemical principles of quality, tolerance to foot rot disease under artificial inoculation and tolerance to drought by physiological and biochemical analyses. Piperine, essential oil and oleoresin ranged from 3.61 - 6.96 per cent, 3.00 - 5.87 per cent and 7.10 - 11.18 per cent, respectively, across the accessions. The accessions with high value of piperine, essential oil and oleoresin were identified as 7293, 7211 and 7289 respectively. The two accessions identified viz. 7293 and 7252 contained more piperine than the highest of Panniyur 2 (6.6 per cent) reported among the released varieties . Artificial inoculation of selected accessions using Phytophthora capsici culture for screening for foot rot disease resistance based on over all disease severity index of both stem and leaf lesions showed that accession 7259 was moderately resistant. The selected accessions did not exhibit significant variation for various physiological and biochemical parameters at field capacity. However higher value of photosynthesis, chlorophyll content, chlorophyll stability index, relative water content and membrane stability index and low leaf temperature were observed for accessions viz. 7215, 7240, P 5 and 7241 after five days and ten days of moisture stress induction following field capacity compared to other accessions. Higher values of proline, SOD, catalase and peroxidase were also observed for these accessions. The visual scoring showed that accessions with higher values for most of physiological and biochemical parameters of drought tolerance viz. 7215, 7240, P5, and 7241 had lesser number of fallen leaves and more number of leaves retained at permanent wilting point (PWP). The accessions 7215 and 7240 took twenty days to reach PWP compared to eleven accessions which took only 16 days to reach PWP. Foliar nutrition with sulphate of potash, IISR - Power mix and Pink Pigmented Facultative Methylotrophs (PPFM) had positive effect on drought tolerance for the accessions (7215, 7240, P5 and 7241) having natural tolerance. The identified accessions with high yield , quality and tolerance to biotic or abiotic stress can be used for further breeding programme.ThesisItem Open Access Evaluation of bhindi hybrids for yield and its components(Department of Plant Breeding, College of Agriculture, Vellayani, 1986) Sheela, M N; Manikantan, Nair, PThesisItem Open Access Genetic studies on induced viable mutants in rice [Oryza sativa L.)(Department of Plant Breeding, College of Agriculture, Vellayani, 1985) Vijayagopal, P D; Gopinathan, Nair VThesisItem Open Access Induction of polyploidy in kacholam(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 1996) Ajithmohan, N K; KAU; Pushkaran, KA 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.ThesisItem Open Access Heterosis breeding in sesame (Sesamum indicum L.).(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2011) Gayathri, G; KAU; Dijee, BastianThe study entitled ‘Heterosis breeding in sesame (Sesamum indicum L.)’ was undertaken at the Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara. The objectives of the study were to collect and evaluate different genotypes of sesame for morphological traits and yield attributes, to identify useful parents producing heterotic crosses and developing hybrids in sesame. The study also intended to develop male sterile lines in sesame through interspecific hybridization with Sesamum malabaricum. Sesamum indicum and Sesamum malabaricum accessions were collected from Kerala and Tamil Nadu and evaluated for their morphological traits. Wide range of variation was noticed for characters like plant height, number of days to flowering and seed yield per plant which contributed maximum to genetic divergence. The genotypes studied were grouped into six clusters. High genotypic coefficient of variation (GCV) was recorded for number of capsules per plant, plant height, seed yield per plant and number of branches per plant. High heritability with high genetic advance as per cent of mean was recorded for number of days to flowering, plant height, number of branches per plant, number of capsules per plant and seed yield per plant. This indicates that the characters are governed by additive gene effects and selection for these traits will be effective. Association analysis revealed that seed yield per plant was correlated to plant height, number of capsules per plant and number of days to flowering. Path coefficient analysis indicated maximum positive direct effect by number of capsules per plant, capsule length, plant height and 1000 seed weight on seed yield per plant. In order to develop hybrids, fourteen parents were selected based on the per se performance of the genotypes. They were crossed in line X tester mating design. Forty eight hybrid combinations obtained were raised in the field along with the parents and evaluated for their heterosis and combining ability effects. Parental genotypes AVTS-06-5, AVTS-06-10, IVTS-06-12, KYM-1, Tilak and TMV-6 were identified as high combiners based on general combining ability (gca) effects. Two combinations viz. AVTS-06-5 X KYM-1 and IVTS-06-12 X TMV-3 had significant values of per se performance, specific combining ability (sca) effects and standard heterosis for seed yield per plant. They can be evaluated for their hybrid vigour over locations and seasons. The crosses AVTS-06-5 X TMV-3, AVTS-06-5 X TMV-6 and TCR 3279A X KYM-1 have been identified as potential cross combinations for isolation of promising segregants as the parents involved in these crosses had high significant gca effects for seed yield per plant but the hybrids recorded non significant sca effects. Interspecific hybridization between S.malabaricum and S.indicum was attempted to develop male sterile lines. Seed set was noticed in three interspecific hybrids which failed to germinate due to embryo abortion. Hence these embryos were rescued and raised in vitro to obtain the hybrids.ThesisItem Open Access Genetic analysis of productivity parameters in horsegram(Department of Plant Breeding, College of Agriculture,Vellayani, 1991) Elizabeth, Mathew; Ramachandran Nair, NA study on the parameters of variability, correlation and path coefficient were undertaken in forty eight horsegram varieties. The study was conducted at the Department of Plant Breeding, College of Agriculture, Vellayani during Rabi 1989. The varieties showed significant differences in all the characters studied. Genotypic coefficient of variation was maximum for days to flowering and minimum for length of pod. High heritability estimates were observed for hundred seed weight and days to flowering. Genetic gain was maximum for days to flowering. Hundred seed weight and days to flowering recorded high heritability and high genetic gain indicating the presence of additive gene action. At the genotypic level seed yield showed high positive correlation with harvest index and number of pods per plant. Path coefficient analysis projected number of pods per plant, length of pod and number of branches as the traits exerting high positive direct effect on seed yield. The study indicated that the model for plant selection in horsegram should be one with more number of branches, long pods and more number of pods per plant. The varieties P. Palayam, CODB-1, Calicut local, PLS-6056 and No.447 were found to fit in this model.
