Kenzhebayeva S.S., Zharassova D., Sarsu F., Minocha S.C. Induced mutations in wheat improvements on nutritional quality of the grain

1Al-Farabi Kazakh National University, Kazakhstan, Almaty 2Plant Breeding and Genetics Section, Joint FAO/IAEA Division, IAEA- Vienna Austria 3University of New Hampshire, Durham, NH, United States *е-mail: kenzhebaevas@mail.ru, Kenzhebaevas@kaznu.kz

Аннотация

Genetic diversity is one of the most key factors for any crops improvement. Modern breeding process
has dramatically narrowed the variation of important traits in many food crops, especially among common
wheat cultivars which are widely used in breeding programs. Being essential bulk of nutrients in the human
diet, there is need genetic enhancement of wheat with more of important nutrients which is one of the most
cost-effective and powerful approach of diminishing global micronutrient malnutrition problem. Biofortification through plant breeding has multiplicative advantages. Over the years, intensive wheat breeding
programmes of common varieties which main focus was in replacement of traditional cultivars by modern
high yielding varieties, leaded to reduction of genetic diversity of breeding lines and varieties of common
mainly by end-use quality characteristics and nutrition quality. Mutagenesis is a powerful tool for crops
improvement and is free of the regulatory restrictions, licensing costs, and societal opposition imposed on
genetically modified organisms. The aim of mutation induction is to increase mutation rate in traits or genes
in a short duration that then can be readily exploited by plant breeders for developing new plant varieties
without any limitations. The article reviews the application of different kinds of mutagens such as chemical
alkylating agents, radiation and transposons which are used to introduce mutagenized populations and the
advantages of physical mutagens such as ionizing radiation as compared to chemical. Mutation induction
with radiation is the most frequently applied treatment to develop direct mutant varieties, accounting for
about 90% of obtained varieties (64% with gamma-rays, 22% with X-rays). In article the results obtained by
authors to use gamma irradiation doses for expanding the genetic diversity of spring wheat and searching
new mutation resource with improved biofortified capacity and for correlations between yield, grain size,
and quality parameters. For this purpose, the seeds of variety Almaken grown in Kazakhstan were irradiated
with 100 Gy and 200 Gy doses from a 60Co source at the Kazakh Nuclear Centre. Our investigation showed
considerable genetic variability in micronutrients such as Fe and Zn concentrations, and protein contents.
Some mutant lines, mostly from the higher dosed germplasm had 2 to 4 times higher grain Fe and Zn concentrations, and protein contents increased by 7-11 % relative to the parent. The article discusses the use
of Ionizing radiation for wheat improvements on nutritional quality of the grain The data show wheat grain
properties can be improved without negatively impacting on crop productivity.
Key words: radiation, wheat biofortification, mutant lines of spring wheat, grain йгфдiron, zinc and
protein concentrations.