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ThesisItem Open Access Genetic studies in red gram (eafanui caiaixL)(Department of Agricultural Botany, College of Horticulture, Vellanikkara, 1988) Radhakrishnan, V V; KAU; Narayanan Namboodiri, K NThesisItem Open Access Studies on induced mutations in rice (Oryza sativa L.)(Division of genetics and plant breeding ,Agricultural college and research institute , Coimbatore., 1971) Gopinathan Nair, V; KAUThesisItem Open Access Effect of planting date, weight of rhizome and spacing on the growth, yield and quality constituents on turmeric (Curcuma longa L)(Department of Horticulture (Plantation Crops & Spices), College of Horticulture, Vellanikkara, 1983) Chatterjee, R K; KAU; Mohanakumaran, NThesisItem 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 Studies on the burrowing nematode radopholus similis (cobb,1893) thorne 1949 on pepper(Piper nigrum L.) and its role in slow wilt disease(Department of plant pathology, University of agricultural sciences, Bangalore, 1976) Venkitesan, T S; Setty, K G HThesisItem Open Access Trematodes of Paramphistomatidae Infecting Domestic Ruminants(Department of Parasitology, College of Veterinary and Animal Sciences, 1987) Tarun Shankar, Nath; KAU; George Varghese, CThe thesis embodied the results of an investigation on the prevalence of amphistome infection and their specific identity in different domestic ruminants (cattle, buffaloes, sheep and goats) of Kerala state. A total of 1490 faecal samples from domestic ruminants were collected from different places of Kerala State during a period from April 1985 to March 1986. These samples were examined by sedimentation technique to detect infection with amphistomes and their prevalence. Viscera of 780 slaughtered/ dead ruminants from different parts of Kerala were examined in addition and the available amphistomes were collected for the study and specific identification. The flukes were studied alive, flattened and stained and in certain cases by microtomy sections. Result of the study indicated that the prevalence of infection was far more in cattle and buffaloes than in sheep and goats. The rate of prevalence in cattle, buffaloes and goats was 20.16%, 28.57% and 3.22% respectively. In slaughtered/dead animals the prevalence was 33.09%, 34.67%, 4.17% and 5.81% respectively in cattle, buffaloes, sheep and goats. The highest prevalence was recorded during the rainy season and lowest in dry/summer season. Prevalence during south west monsoon was 38.08% and 20.73% during North East monsoon. The seasonal prevalence hardly varied between cattle and buffaloes but it was consistently low in sheep and goats. Most of the prevalence in all animals were of mixed origin. A total number of 17 species belonging to eight genera of amphistomes were identified. Cevlonocotyle spinicephalus (Tandon, 1955) was recorded from new hosts i.e, cattle and goats, cotylophoron chauhani from goats, in addition to the already reported hosts, buffaloes and sheep respectively. The following conclusions are drawn on the basis of the results of this study: Amphistomes are most prevalent in cattle and buffaloes. Though the infection with amphistomes exists throughout the year, it is definitely more in monsoon seasons. Ceylonocotyle spinicephalus (Tandon, 1955) occurs in cattle and goats and cotylophoron chauhani (Gupta and Gupta, 1972 ) in goats also.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 Anthracnose disease of vegetable cowpea [Vigna unguiculata subsp. sesquipedalis (L.) verdcourt](Department of Plant Pathology, College of Horticulture, Vellanikkara, 1999) Praveen Kumar, M; KAU; Sally Mathew, KA study on vanous aspects of anthracnose disease of cowpea was conducted at College of Horticulture, Vellanikkara during 1997-98. Etiological studies revealed Colletotrichum lindemuthianum (Sacc. and Magn.) Br. and Cav. as the main pathogen causing anthracnose disease in Kerala and the pathogen was found to be seed borne. Among the 50 genotypes tested, Kanakamony was found immune to the disease and seven genotypes were highly resistant to the disease. In ( disease management studies, all fungicides, botanicals and antagonist Trichoderma viride were equally effective under in vitro and field conditions. As far as disease control, yield and C:B ratio were concerned, mancozeb was found to be the best treatment. Summer season was found to be the best season for cowpea cultivation in areas where anthracnose is a problem. In crop loss assessment, significant difference was noticed between carbendazim treated and untreated plots in case of disease infection and yield, and yield loss of 53.85 per cent was recorded under natural condition due to this-disease.ThesisItem Open Access Biocontrol of rhizome rot of ginger using selected antagonists(Department of Plant Pathology, College of Horticulture, Vellanikkara, 1999) Julie George, K; KAU; Sukumaravarma, MRhizome rot of ginger cas used by Pythium aphantdermatum (Edson) Fitzpatrick is one of the most destructive diseases of ginger in Kerala. The pathogen was isolated and its pathogenecity was established by Koch's postulates in ginger variety Rio-de-Jenerio. Among the various food bases evaluated, for the mass multiplication of selected antagonists, rice hull was found to be significantly superior to all others to obtain maximum growth for Trichoderma viride and Aspergillus flavus. For Aspergillus niger, rice bran was found to be significantly superior. The results on the effect of various treatments on germination showed that there was no significant difference among the treatments. The effect of antagonists on the pre- emergence rotting and post-emergence rotting (rhizome rot) were studied. In plots where antagonists (T viride, Aflavus or A. niger) or fungicides (mancozeb or copper oxychloride) were applied either as seed treatment or as soil incorporation at the time of planting, the pre-emergence rotting was not observed. The plot in which the antagonists T. vtride, A. mger and At flavus were applied in combination at 60 and 120 OAP, recorded the minimum rhizome rot incidence compared to other treatments. The plots in which the antagonists were applied twice, i.e., 60 and 120 OAP, the rhizome rot incidence was minimum compared to the plots with only one time application of antagonists. The maximum population of the pathogen P. aphanidermatum. was observed in plot where A. flavus was applied in combination with mancozeb. The multiplication of selected antagonists, 7: viride, A. flavus and A. niger in soil was found out by estimating their population at different stages. The population of T. virtde was maximum in plots where it was applied in combination with mancozeb in most of the period. The soil application of the combination of antagonists T. viride, A. flavus and A. niger did not affect the multiplication of anyone of them in soil. In general, soil incorporation of antagonists was found to helping in their mulitplication profusely compared to the seed treatment. The incorporation of the antagonists A. flavus and A. niger to the plots, twice was found to be superior than applying them only once, for getting maximum multiplication of propagules in soil. The result on the compatibility of antagonist with fungicide in field condition revealed that the antagonist T viride was quite compatible with mancozeb whereas A. flavus and A. niger were compatible with both fungicides tested (mancozeb and copper oxychloride). The treatments which was found to be superior in minimising the incidence of rhizome rot of ginger viz., T 16 (soil incorporation of T vir/de, A. niger at 60 and 120 DAP) and TI9 (soil incorporation of I: viride, A. niger and A. flavus) also recorded the maximum yield of ginger.
