Harnessing mutant donor plants for microspore culture in Indian mustard [Brassica juncea (L.) Czern and Coss]

Abstract

Haploid mutagenesis offers several advantages over conventional (seed) approach. However, its potential has not been utilised for Brassica juncea, an important oilseed. In this study, mutant donor plants of three Indian B. juncea genotypes, generated by ethyl methanesulfonate (EMS) and ethyl nitrosourea (ENU), were used for microspore culture. The response of mutant donor plants was about 100 times lower than non-mutant controls; a total of 9,411 embryos were produced from the EMS treated donor plants, while microspores isolated from ENU treated donors did not yield any embryos. The lethality of induced mutations demonstrated itself mainly as the induction of abnormal embryos (80%), failure of germination (70%) and failure of plantlet development (70%). Nine doubled haploid (DH) mutant lines and three non-mutant DH lines obtained through this approach were tested for agronomic and biochemical variation over two growing seasons. High variability was observed and stable mutants were recovered for reduced height (125 vs. 168 cm for the control), appressed pod character, altered fatty acid composition higher protein proportion in de-oiled meal (48%) and a lower glucosinolate content in de-oiled meal (59.5 lM/g) relative to controls. The approach demonstrates that despite severe reduction in efficiency of the DH line production, valuable mutants can be recovered from mutated donor plants.

Microspore Induced Doubled Haploids Production from Ethyl Methanesulfonate (EMS) Soaked Flower Buds Is an Efficient Strategy for Mutagenesis in Chinese Cabbage

“…A semi-dwarf mutant of B. napus was isolated from doubled haploid plants following EMS treatment of somatic embryos of microspore cultures (Liu et al, 2010). Mutants with a reduced height, altered fatty acid composition, and lower glucosinolate content were obtained by culturing microspores of the donor plants of Indian mustard ( B. juncea ) generated by treatment with EMS and ethyl nitrosourea (ENU; Prem et al, 2012). In the present study, five genotypes of Chinese cabbage were used to evaluate the effect of EMS on microspore development, embryo production rate, and seedling rate by soaking buds with different doses of EMS for different durations.…”