Effect of gamma irradiations on seed germination, seedling growth and mutation induction in Cluster bean [Cyamopsis tetragonoloba (L.) Taub.]

Abstract

Cluster bean is an annual drought hardy legume crop mainly cultivated in arid regions receiving scanty (150-400 mm) and erratic rainfall during crop growth period. For the enhancement of genetic diversity in this locally adapted crop, three genotypes HG-2-20 (hispid branched), CAZG-15-6 (branched glabrous) and CAZG 15-3 (single stem, hispid and regular bearing) were irradiated with gamma rays (100-1600 gray) with 100 gray intervals. The mutation rate increased with increasing dose up to 300 gray, there after gradually reduced indicating decline in rate of recovery of mutations with respect to increasing M 1 damage. At higher dose of 800 gray, mutation efficiency drastically reduced with reduced survival and high level of pollen sterility in M 1 generation. Beyond 800 Gy dose all the seedlings died within a few days (15 d) of germination. Based on mutation efficiency and effectiveness a gamma radiation dose between wide ranges (200-700 Gy) was found appropriate for inducing variability. The mutagenesis has generated, a good amount of diversity for economically and agronomically important traits.

Gamma-Rays and Microwave Irradiation Influence on Guar (Cyamopsis Tetragonoloba): I - Markers Assisted Selection for Responding to Mutagenic Agents

“…Mutagenesis is a powerful tool for creating variation in a crop like a guar, where exploitable and favorable genetic variability is very meager (Arora and Pahuja, 2008). Some morphological mutants were also reported earlier in guar (Bhosale and Kothekar, 2010;Patil and Rane, 2015;Mahla et al, 2018).…”

“…In M 1 generation, it was also higher at 53.6 and 44.2 cm for 3 and 4 min, respectively, as well as, in M 2 , at 34.3 and 25.3 cm for 3 and 4 min, respectively, as compared with G2503T and G2504T in M 1 at 32.8 and 24.6, respectively, and with G2503D and G2504D in M 2 (Figure 1). In contrast, Mahla et al (2018) reported that the genotypic response concerning plant height was less conspicuous and the reduction was progressive, starting from 100 to 800 Gy. Also, the plant height was increased by irradiation in only one of the two investigated varieties.…”

“…The gradual increase in sterile plants indicated their inducibility in response to radiation treatment. The mutations with respect to M 1 damage first increased, with the increasing dose of gamma ray up to 300 Gy, thereafter, gradually reduced, indicating a decline in the rate of recovery of mutations with respect to increasing M 1 damage (Mahla et al, 2018).…”

“…An increase in induced variation in M 2 progenies of guar cv. RGC 197 obtained by gamma irradiation (10, 30, 50, 60, 70, and 80 kR) was noticed in plant height (Amrita and Jain, 2003;Mahla et al, 2018). Arora and Pahuja (2008) have observed an increase in peduncle length and plant height.…”

“…The frequency of mutants dose dependent mutation frequency was recorded while working with physical (gamma rays) and chemical (EMS) mutagens in guar by Bhosale and Kothekar (2010), Velu et al (2012), and Mahla et al (2018). Mutagenesis is a powerful tool for creating variation in a crop like a guar, where exploitable and favorable genetic variability is very meager (Arora and Pahuja, 2008).…”