59-05-032 Proceeding

65 Proceedings of the Princess Maha Chakri Sirindhorn Congress B. Yield contributing traits of selected mutants Nine mutants were compared in yield contributing traits with the mean value of parent cultivar (Yezin-7) in M2 generation (Table 2). Both positive and negative occurred as compared to the parent cultivar. The plant height ranged from 162.7 cm to 345.5 cm as compared to 276.2 cm in the parent. Tall mutant and high yielding mutant were significantly higher than the control. Dwarf mutant showed over 1.5 times and 2 times decrease in plant height compared to the control and tall mutant respectively. For the stemwidth, fourmutants (broad leaf mutant, compact panicle mutant, bold seedmutant and high yielding mutant) showed significant increase over the control. The smallest stem was observed in narrow leaf mutant (6.2 cm). Significant increase in panicle length was observed in high yielding mutant (35.7 cm). Dwarf mutant, compact panicle mutant and small seed mutant showed a significant decrease in panicle length as compare to control (28.8 cm). Among all mutants, the largest panicle width was observed in high yielding mutant (30.5 cm) while dwarf mutant had the smallest panicle width. The maximum number of seeds per plant compared to control was observed in high yielding mutant followed by small seed mutant and compact panicle mutant. These mutants produced more than double the number of seeds per plant as compared to control (624). Almost all mutants produced larger the number of seeds per plant than the control except early mutant. Only two mutants (broad leaf mutant and bold seed mutant) had higher 100 seed weight than the control. Small seed mutant showed about 2 times and 2.5 times decrease in seed size compared to the control and bold seed mutant respectively. The highest yield per plant compared to the control was observed inhigh yieldingmutant (25.13 g) followed by compact panicle mutant (20.44 g). Broad leaf mutant and bold seed mutant also showed significant increase in yield per plant over the control (12.36 g). The minimum yield per plant was found in early mutant (9.66 g). In all the mutants, days to maturity ranged from 125 to 137 days. The early mutant matured 8 days earlier than the control. Broad leaf mutant and small seed mutant showed similar maturity as the parent. High yielding mutant matured only one day later than the control.