The high-yielding cultural techniques and some physiological-ecological characteristics were studied on a three-line late hybrid rice Weiyou 198 at the National Rice Engineering Base (Liling, Hunan) in 1996～1997. The combination yielded a mean of 8.8 t/hm 2 on a planting area of 7.2 hm 2 when it was planted as double cropping late rice. The main reasons for high yield of Weiyou 198 were found as follows: (1) It had large panicle (153.2 spikelets/panicle), heavy 1 000-grain weight (31.6 g) and high seed setting percentage (82.3%). (2) It had hi...
