2021 Vol.27 No.2 PP 191­-196

https://doi.org/10.33451/florafauna.v27i2pp191-196

Mutation breeding in six rowed barley: Screening for stem rust resistance in certain induced mutants

Shipra Raj

Department of Botany,
SM College BHAGALPUR (BIHAR) INDIA.
*Corresponding Author : Email : shipraraj15@gmail.com

ABSTRACT

During the induced mutagenesis in six rowed barley, 18 mutant lines were isolated from the M2 and M3 generations. Thirteen lines were induced by gamma rays, four by EMS and one by HA. These lines were screened for resistance to stem rust and loss assessment. Mutants were grown in field as well as in earthen pots. Artificial inoculums were provided in condition suitable for rust occurrence. Rust reaction was recorded according to modified Cabb’s scale and the rust intensity was classified as 0,5, 10, 25, 40 and 65 percent. Lines K50-38, K50-97, K50-102 and K40-73 were completely free from infection (0 %) and thought to be immune lines(I). K50-47, KE-4-47 and G50-47 exhibited traces of symptoms and placed under 5% intensity and were very resistant(R). Line KE2-63 exhibited 10% intensity and classified as moderately resistant(MR). Line K50-44; K40-11, K40-67, K30-91, KE3-75, G50-35 and GH3-32 showed 25% intensity of pustules and were put into moderately susceptible(MS) class. One line K30-82 showed 40% intensity and classified as susceptible(S), while line KE4-87 exihibited 65% intensity and was classified as heavily susceptible. Class 100 percent was not observed. Immune, very resistant and moderately resistant were identified as resistant lines and selected for further study, while moderately susceptible and heavily susceptible lines were identified as susceptible lines and discarded. Reduction in yield contributing traits i.e. number of grains/spike, test weight, seed yield and biological yield was also observed which was positively correlated with disease intensity.

Key words : Evaluation, Immune, Inoculums, Pustules intensity, Resistant, Susceptible.