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Item Association of yield and its components in bhindi(Kerala Agricultural University, 1988) Sheela, M N; MAnikantan Nair, P; Gopinathan Nair, VItem Inheritance of fruit colour in normal and irradiated progenies of brinjal(Kerala Agricultural University, 1980) Gopimony, R; Mary K George; Gopinathan Nair, VThe inheritance of fruit colour in brinja! (Solarium metongena) was studied by analysing the progeny belonging to the F, M2, FjM^ and F3M generations resulting from a cross between varieties insanum and purple giant followed by gamma irradiation. The F0 phenotypic frequencies fitted very well with the dihybrid ratio indicating that the fruit colour is governed by two independently inherited genes. Three colour mutants, namely, purple, mottled green and white were induced in the F]MI generation by the irradiation. The appearance of these mutants is explained as due to independent mutations at either or both of the two genetic loci. The colour pattern in the F3M., progenies derived from the F, Mj mutants substantiates the two gene mechanism for the inheritance of fruit colour. The genotypes for the different colour types in the FL, F, and FlMl mutants have been indicated and discussed.Item Relative mutagenic effects of ionizing radiations and alkylating chemicals in rice(Kerala Agricultural University, 1981) Gopinathan Nair, VStudies were undertaken on the relative mutagenic effects of three ionizing radiations (X-rays, gamma rays, fast neutrons) and five alkylating chemicals (DES, EMS, MMS, NMH, MNNG) in rice. Observations on seed germination, seedling survival, seedling height, seed fertility and chlorophyll deficient chimeras were made in the IV^ generation. The M3 generation was grown as M, ear progenies. Chlorophyll mutation frequency, segregation percentage and mutant spectrum were estimated. The mutagenic effectiveness and efficiency were also worked out. Germination of seeds was not affected by radiations even at high doses. Chemical mutagens inhibited germination. Radiation induced lethality was manifested subsequent to germination, whereas lethality induced by chemical mutagens was expressed mostly through inhibition of germination. Seedling height was reduced fay mutagen treatments • Gamma rays and NMH were more effective in this respect Radiations induced high degreesof sterility than chemical mutagens. Fast neutrons induced more sterility per unit dose than sparsely ionizing radiations. Chlorophyll deficient sectors were more frequent in M; plants after treatment with NMH and EMS. NMH, however, was more effective than EMS in this respect. Mutation frequency estimated on M,ear basis was as efficient as that on M.J plant basis because the study was confined to pre-formed ears. Gamma rays fast neutrons, EMS and NMH had induced high frequencies of chlorophyll mutations. Per unit dose, fast neutrons was more effective than gamma rays and atequimolar concentrations NMH was more effective than EMS. The mean segregation percentages were higher after treatment with radiation than with chemical mutagens. The spectra of mutants differed between radiations and chemical mutagens. Albina was the most frequent type following irradiation. In chemical mutagen treatments, the frequency of albina was low and that of viridis was high. Radiations were more effective than chemical mutagens• Mutagenic effectiveness decreased with increase in doses of mutagens. This was due to the failure of mutation frequency to increase proportinately with increase in mutagen doses. Mutagenic efficiency was higher for radiations when estimated on the basis of lethality and injury whereas, based on sterility, chemical mutagens were more efficient. Mutagenic efficiency also decreased with increase in doses of mutagens. The most effective as weli as efficient radiation was fast neutrons Among chemical mutagens the most effective was NMH whereas the most efficient was EMS.Item New techniques of selfing and crossing in sesame(Kerala Agricultural University, 1981) Sverup John; Gopinathan Nair, VItem Genetic analysis of multiloculed pod character in sesame(Kerala Agricultural University, 1981) Sverup John; Gopinathan Nair, VGenetic analysis of he multiloculed condition in sesame was undertaken. Four multiloculed types isolated from a varietal collection and the four loculed type (Kayamkulam-1) were crossed in all passible combinations. The pod type in the hybrids was compared with that of the parents and conclusions drawn. The multiloculed condition was recessive to the four loculed condition. Estimation of the number of genes responsible for this character revealed the operation of two independent recessive genes symbolised as i ' and 'I/. Either of these in hoTiozygous condition produced multilocular expression. Presence of these two genes together in a genotype in the double recessive condition can produce a better expression of this character.Item Performance of cardamom varieties in the plains(Kerala Agricultural University, 1982) Gopimony, R; Gopinathan Nair, VItem Easy method of hybrid seed production in bhindi(Kerala Agricultural University, 1982) Gopimony, R; Gopinathan Nair, VItem The mutual dependance of M1 fertility and M2 mutations in rice(Kerala Agricultural University, 1982) Gopinathan Nair, VThe mutual dependance of Mj fertility and Ma mutations in rice was studied after treatment with gamma rays and EMS. The frequency of chlorophyll mutations increased with decrease in seed fertility when M, ears were selected at random. However, at the lowest fertility class the mutation frequency was low. This reduction is attributed to the elimination of mutants in the high sterility class. The mutation yield can therefore be significantly enhanced by selecting M1 ears of low fertility. The segregation ratio of mutants increased as fertility decreased. Mutation spectrum was however not influenced by M1 fertility. This makes selection for fertility quite ineffective in altering the mutation spectrum.Item Floral biology of Indian lemongrass Cymbopogon flexuosus stapf(Kerala Agricultural University, 1982) Luckins C Babu; Mercy, S T; Gopinathan Nair, VItem Evaluation of cowpea varieties for fodder and grain yield(Kerala Agricultural University, 1982) Gopimony, R; Sunny K Oommen; Gopinathan Nair, V