Abstract:

Plant characteristics of 19 combinations of early rice and 16 combinations of late rice were studied by variance methods. Results showed that high yield rice combination had large sink, high potential yield and powerful ability in dry matter accumulation and N uptake, and high grain weight for early rice and more grain number for late rice. Basic physiologic characteristics of high yielding rice combination were as follows: 110–115 d of growth duration, 95–105 cm of height, long top internode, long length and big drop-angle of the second and third leaves of top, long spike, large number of the first and second panicle-branches, 100–130 spikelets per panicle, 27–29 g of 1000-grain weight, and over 2.5 g for the weight per panicle for early rice; 120–125 d of growth duration, 100–110 cm of height, long top internode, stout stem, medium length and small drop-angle of the top leaves, long spike, large number of the panicle-branches especially of the second panicle-branches, high density of the grain, 120–150 spikelets per panicle, 25–27 g of 1000-grain weight, and about 3.0 g for the weight per panicle for late rice.

Key words: Double cropping rice, Characteristic of plant type, Yield