Summary Seeds of Capsicum annuum L. var. G-4 Bhagyalakshmi were subjected to 15, 25, 35 kR doses of gamma ray, and 0.8% and 1% ethyl methane sulphonate (EMS). Effects of mutagenic treatments of meiosis viz. chromosomal anamolies, pollen sterility, seed sterility and survival percentage in M2 generation have been reported. EMS was found more effective in inducing meiotic irregularities than gamma ray treatment. A dose dependent increase in meiotic anomalies was obtained with all the mutagenic treatments.Mutations can be beneficially utilized for tailoring better varieties of crop plants. But in general, ionizing radiations and chemical mutagens like ethyl methane sulphonate (EMS) effects a wide range of chromosomal alterations resulting in to abnormal behaviour during meiosis, leading to various degree of sterility. Further, the cytological abnormalities during meiosis has also been regarded as one of the dependable parameters for estimating mutagenic sensitivity of a species. Though considerable work has been done on induced mutation studies in red pepper (Bansal and Dalmirsingh (1972), Han (1974), Auni et al. (1978), Lakshmi and Bapa Rao (1978), Kumar et al. (1986), Meshram et al. (1992)), there was no current report available on physical and chemical mutagen effect on meiosis in the existing promising varieties of Capsicum annuum L. Hence, the present study is undertaken to assess the meiotic consequences of chromosomal aberrations induced by separate and combined application of gamma rays and EMS. Materials and methodsDry seeds of Indian popular chilli variety G-4-Bhagyalakshmi were subjected to mutagenic treatment with gamma rays and ethyl methane sulphonate (EMS). Seeds were irradiated with 15, 25, 35 kR doses of gamma rays from 6°Co source. A second set of seeds were soaked in 0.8% and 1.0% solution of EMS for 12 h at 23 -± 1°C. Another set of seeds were also subjected to combined doses of gamma rays and EMS in the following combinations; i) 15 kR+ 0.8% EMS ii) 15 kR+ 1% EMS iii) 25 kR+ 0.8% EMS iv) 25 kR+ 1% EMS v) 35 kR+ 0.8% EMS iv) 35 kR+ 1% EMS The control seeds were soaked in distilled water for 24 h at room temperature. After treatments seeds were throughly washed and sown in the nursery beds along with control seeds. Forty-five old day seedlings were transplanted in the field. For meiotic studies, young flower buds were fixed in Carnoy's fluid (6 : 3 : 1) for 24 h and then transferred to 70% ethyl alcohol. Squash preparations were made with 2% acetocarmine. Results and discussionsThe pollen mother cells (PMC's) of control plant showed regular 12 bivalent uniformly at

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The role of the different genome combinations in a polyploid on phenotypic stability was analysed in wheat and triticale. Twelve genotypes with four genome combinations (AABB, AABBDD, AABBRR and AABBDDRR) were raised in eight artificially created environments. The data on grains per spike, 100-grain weight and grain yield per plant were recorded and analysed following the models of Perkins and Jinks (1968) and Eberhart and Russell (1966). The results revealed that in polyploid species the genes for stability were not uniformly distributed in different genomes. It was therefore inferred that stability may largely depend on the gene combination rather than on the genome combination.

The dough characteristics of fifty popular Indian hexaploid wheat varieties were assessed by testing various rheological properties using a Brabender Farinograph and an Extensograph. These studies were aimed at evaluating the flour quality and functionality of the wheat dough. Based on the rheological dough properties of 50 Indian hexaploid wheat varieties it was recommended that 13 wheats could be useful for blending purposes, 31 varieties could be used for both bread and chapatti making, and the remaining 6 wheats were found suitable for biscuit making. The outcome of the experiments will be useful for plant breeders, millers and bakers.

The chromosome behaviour of wheat and rye genomes were discussed in triticale with reference to cytological and other characters. Rye chromosomes show preferential involve ment in meiotic disturbances and were attributed to differential meiotic duration, genome allo cycly and to the amount of heterochromatin. Both wheat and rye chromosomes influence each other homologous and homoeologous pairing either through increase in the dose of genome or individual chromosomes or genes. Cytoplasmic-nuclear interactions also regulate the meiotic chromosome pairing of wheat and rye chromosomes and other characters in triticale. Chro mosome substitutions and translocations involving A, B, D and R-genome chromosomes occur in most of the triticales. Variability in the expression of individual genes of wheat and rye noticed in triticale.

Attempts were made to produce tetraploid triticales by crossing 6x triticales with diploid rye. In F 2 , the chromosome number was reduced to between 15 and 23 except in three plants, where the chromosome number was 28, 32 and 38, respectively. An increased frequency of ring bivalents was observed in many F 4 plants. In the progeny of the plant with 28 chromosomes, desired plants (four) with 2n = 28 chromosomes were obtained. Data on various agronomic characters were recorded on the progeny of these plants in F 5 . Reasonably good fertility was noticed in these tetraploid triticale forms.