Effect of Planting Dates, Gibberellic and Boric Acid on Morphological Characters and Seed Yield in Rice Hybrid Pusa RH-10

Abstract

Pusa Rice Hybrid-10 (Pusa RH-10) is world's first fine grain aromatic rice hybrid. Therefore, an attempt was made to maximize seed yield. The study was conducted during kharif 2004 and 2005 at ICAR- IARI, New Delhi, involving three planting dates in twelve days interval, from first week of June. The seeds of A and R lines were sown in the nursery for three dates and proper staggered sowing was done to obtain synchrony of flowering. Transplanting of both the parents was done on same day when the seedlings were four weeks old for each date of sowing. Gibberellic acid was applied in three doses viz., 50 g/ha, 100 g/ha and 150 g/ha in split application in the ratio (40:60) in two consecutive days and in three (25: 50:25) ratios, in three consecutive days. One per cent boric acid was also applied along with gibberellic acid. There was considerable effect of climatic conditions like rainfall, temperature, relative humidity and wind velocity on flowering and morphological parameters. There was a decreasing trend in flowering and morphological parameters with delayed sowing. Sowing during 1st week of June was found most favorable for hybrid seed production of Pusa RH-10. GA, had profound effect on flowering and morphological parameters. GA3 @ 150 g/ha + 1% boric acid sprayed in a ratio of 25: 50: 25, on consecutive days, during panicle emergence provided maximum seed yield.