59-05-032 Proceeding

62 Proceedings of the Princess Maha Chakri Sirindhorn Congress THE IMPROVEMENTOF SORGHUM( SORGHUMBICOLOR L.) FOR HIGH YIELD THROUGH INDUCED MUTATION Khaing Wah Htun 1 , Nay Chi Win 1 and Myat Minn 1 Abstract : Sorghum is used as alternative food source, animal feed and rawmaterial for industries. A locally adapted cultivar of sorghum (Yezin-7) was irradiated with different doses of Gamma ray (0 Gy–700 Gy), with increment of 100 Gy. Attempts were made to induce genetic variability in yield contributing traits in sorghum. Wide range of viable morphological and physiological mutants were screened and isolated in M2 generation such as chlorophyll mutations (albino, viridis, striata); leaf mutations (narrow, broad); morphological mutations (early, dwarf, tall, twin stem); panicle mutations (twin panicle, compact, spread) and seed mutations (pink, brown, long, round, bold, small).The highest total frequency of mutationwas found at 400Gy.The earlymutant matured 8 days earlier than the parent variety. Tall mutant was two-fold higher than dwarf mutant. Small seed mutant showed two times decrease in seed size compared to control. Compact panicle mutant, small seed mutant and high yielding mutant displayed two-fold increase in number of seeds per plant compared to control. Considerable variationwas observed with regards to number of seeds per plant and seed size. High yieldingmutant that was observed at 400Gy produced double the yield per plant as compared to control. Induced mutants showed both positive and negative increase in the yield contributing traits. Keywords : Sorghum, Gamma ray, morphological mutants, 400 Gy, high yielding mutant I. Introduction Sorghum ( Sorghum bicolor L.) is grown mainly in the semi-arid area of the tropics and sub-tropics and fifth in term of importance among the world’s cereals [1]. It is also known to have wide adaptability, ranging from lowland, medium and highland altitude. Compared to maize, sorghum is also tolerant towater lodging, salinity and aluminum toxicity [2].The grain can be used for flour to make bread, porridge and for brewing beer. The large juicy sweet stems are utilized for chewing andmaking syrup, ethanol and sugar [3]. It is an important stable food for more than 300 million people and feed for cattle in Asia and Africa [4]. As a food crop, sorghum was reported to have high nutrition so that it can be used for substituting rice [5] [6]. For being used directly as food or in a food industry, white sorghum is usually more preferable [6]. Mutation breeding is one of the plant breeding techniques used for creating genetic variability in traits and to improve the yield of crop plants [7]. The most popular mutagen used for creating genetic variability is Gamma irradiation [8]. The widespread use of induced mutants in plant breeding programmes throughout the world has led to the official release of more than 1 Department of Biotechnology, Mandalay Technological University, The Republic of the Union of Myanmar