In the present investigation the seeds of Pigeon pea (Cajanus cajan (L.) Millsp) were treated with different doses of gamma radiation (05KR, 10KR, 15KR, 20KR, 25KR, 30KR, 35KR, 40KR, 45KR, and 50KR) and concentration of Ethyl Methane Sulphonate (05mM, 10mM, 15mM, 20mM, 25mM, 30mM, 35mM, 40mM, 45mM, and 50mM) for studying seed germination, seedling height, (shoot and root), seedling injury, seedling vigour index, and seedling survival of plants at 30 th day. The seed germination percentage was decreased with increased in the concentration/doses when compared to control. The LD 50 (Lethal dose) value was determined based upon the seed germination percentage. The 50 percentage of seed germination and reduction was observed in 20KR of gamma rays and 25mM of EMS and it is considered as LD 50 value for both the treatments. The decrease in seed germination was more prominent with gamma rays than that of EMS treatments. The seedling parameters of gamma rays and EMS treated seedlings were progressively decreased with increase dose/concentration in all mutagenic treatments when compared to control. The maximum seedling parameters were observed in 05KR of gamma rays and 05mM of EMS. Minimum seedling parameters were observed in 50mM of EMS and 50KR of gamma rays respectively.

An experiment was conducted to evaluate the performance of forty-nine chrysanthemum genotypes for desirable horticultural traits at ICAR-Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bengaluru from 2015-17. Significant variations were observed for various vegetative and flowering traits during both years. The results from the pooled data of two years showed that among the genotypes evaluated, maximum plant height was recorded in Arka Chandrakant (69.59 cm), maximum flower diameter in Arka Ravikiran (9.00 cm) and maximum weight of 100 flowers in Marigold (925.04 g). The genotype Roopanjali produced maximum number of flowers per plant (1199.17). Pusa Anmol recorded the minimum number of days to first flowering (60.48 days) while Roopanjali the longest period to first flowering (201.56 days). The genotypes with superior vegetative and floral traits desirable for the different segments of the floriculture industry like loose flower, cut flower and pot plant trade can be utilized in further improvement of chrysanthemum.

The mitotic effect of physical mutagen gamma rays was observed in the root tip cells of Ashwagandha. The Chromosome analysis has been showed as an important tool for establish variability of the plant seed by use of physical mutagen gamma rays. The gamma rays have of low wavelength and high penetrable power. The plant has tremendous medicinal values and it is known from ancient times. The dry and well matured seeds of ashwagandha were irradiated with different doses of gamma rays viz., 5,10,15,20,25,30,35, 40, 45 and 50 KR respectively. The chromosome number of control plant is 2n = 48. The gamma rays affect the normal cytological behavior of ashwagandha species. The chromosomal aberrations increase with increase in the doses of gamma rays to optimum level of 30KR, because it causes changes in the chromosome structure, cellular structure and metabolism of plants. The chromosome aberration like, Sticky metaphase, Precocious moment chromosome, Fragments, Anaphasic bridge, Anaphasic laggard, Telophasic laggard. The present investigation was carried out to study the cytogenetic analysis of the species Withania somnifera. The chromosomal aberration increases with increase in the doses to optimum level (50 KR) of physical mutagen gamma rays.

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The cytological studies provide more information regarding the response of a genotype to the particular mutagen and also provide chances to select desirable characters. The seeds of pigeon pea were subjected to different doses and concentrations of gamma rays and ethyl methane sulphonate (EMS). The effects of different mutagenic treatments on mitosis chromosomal behavior have been studied in both the mutagens. Different types of mitotic aberrations like stickiness, precocious movement, bridge, clumping of chromosome and laggards, etc., were observed in all the treatments. However, the gamma rays treatments proved to be more effective in inducing mitotic aberrations as compared to EMS. The frequency of laggard was high when compared to other mitotic aberrations. The reduction in mitotic index and relative deviation rate frequency were observed with increase in doses and conc. of both the mutagenic treatments and gamma rays were found to be more effective than EMS treatments.