tailieunhanh - Influence of stubble height and nitrogen fertilizer level on seed yield and quality in KRH-4 hybrid rice seed production

A field experiment was carried out during rabi 2016 and 2017 at the Agricultural Research Station, Malagi, UAS, Dharwad to study the influence of stubble height and nitrogen fertilizer level on ratoon seed yield in KRH-4 hybrid rice seed production. The experiment consisted of two factors. Factor one was the stubble height which included 3 cutting heights namely H1: (15 cm A line and 15 cm R line), H2: (15 cm A line and 20 cm R line) and H3: (20 cm A line and 20 cm R line). Factor two was the nitrogen fertilizer levels viz., F1: (25% N of main crop), F2: (50% N of main crop), F3: (75% N of main crop) and F4: (100% N of main crop) and the treatment combinations were replicated thrice. The results revealed that among the stubble heights H3 recorded the highest regeneration percentage ( % and % in 2016 and 2017 respectively), highest plant height ( cm and cm in 2016 and 2017 respectively), whereas the highest seed set ( and in 2016 and 2017 respectively) and seed yield per hectare (375 kg and 425 kg in 2016 and 2017 respectively) recorded by H2. Among the nitrogen levels F4 recorded the highest regeneration ( and in 2016 and 2017 respectively) and highest plant height ( cm and cm in 2016 and 2017 respectively) whereas the F3 recorded highest seed yield per hectare (395 kg and 450 kg in 2016 and 2017 respectively). Among the combinations H2F3 recorded the highest seed yield per hectare (449 kg and 502 kg in 2016 and 2017 respectively) due to effective synchrony of flowering between the parental lines. The study indicated that stubble height at H2:(15 cm A line and 20 cm R line) together with nitrogen fertilizer level of F3: (75% N of main crop) is ideal in achieving the better synchrony of flowering as well as better regeneration of ratoon to get higher seed yield in KRH-4 hybrid rice. | Influence of stubble height and nitrogen fertilizer level on seed yield and quality in KRH-4 hybrid rice seed production