Stand establishment practices affect performance of intermediate deepwater rice

Results showed that plant height of direct seeded rice was similar under various seeding rates. In the transplanted crop, height was greater for clonal tillers than for nursery seedlings. Tiller number on 10 Sep and panicles at maturity was not affected in the direct seeded crop (due to the removal of clonal tillers from the plots sown at 600 seeds/sq.m.) when compared with the undisturbed crops sown at 400 seeds/sq.m. Under transplanted conditions, however, tillers and panicles/sq.m. were significantly less than under direct seeding, particularly in the late planted crop. This was caused by mortality of seedlings at or immediately after planting and less tillering because of excess water stagnation. Panicle weight was highest in the crop planted on 20 Jul. Lower panicle weight in the direct seeded crop was observed because of relatively more panicles/sq.m.; in the 10 Aug transplanted crop, it was because of less dry matter accumulation from the shorter growth duration. The crop transplanted on 20 Jul produced the highest grain yield, significantly more than that of the other treatments. The clonally propagated crop performed better than the others because it was taller, had more dry weight, and could acclimatize more easily to flooded conditions. The direct seeded crop was at par with the 20 Jul transplanted crop of nursery seedlings. Yield did not decrease with the removal of clonal tillers. Late transplanting resulted in the lowest yield because of fewer and lighter panicles. Clonal propagation was superior to nursery-grown seedlings. Clonal tillers of rice uprooted from a well-established direct seeded crop may be planted for higher productivity under excess water conditions. This practice is promising for use when early flash floods have partially damaged crop and nursery seedlings are not available for late planting