| Tiller angle is one of the important traits constituted to plant type of rice (Oryza sativa L.). In this paper it refers to the angle between tiller and horizontal. Applied with dwarf and sterility gene, rice yield had got a dramatic increase in twenty century. Now, Innovation for plant type material is vital to utilization of heterosis in rice high-yield breeding. Although the research on ecophysiology and genetics of rice tiller angle to improve effective panicle and yield had been well documented, most of them only focused on a certain develomental stage, e.g. early stage or maturity. However, studies on rice tiller ange during the whole developmental stage were fewer, and the research of dynamic tiller angle material was not reported.In the paper, to research tiller angle, ontogeny, yield and its components of dynamic tiller angle rice DI508, three ecological experiments, seeding date, planting density and shading were conducted in paddy field. The main results are summarized as follows:1. DI508 showed semi-scattered at the tillering stage and upright after the heading stage. At the tillering stage, the angle of first, second and third primary tiller were 50.8°, 52°and 59.2°respectively, and were gradually up to 90°after heading stage. Meanwhile, at tillering stage the average light transmition rate of DI508 was lower than erect rice 9308, thus the intercept leaf area and the biomass were also larger. In additon, the average net photosynthesis rate of three top leaves of DI508 were 26.89, 25.69 and 24.83μmol.m-2.s-1 from booting stage to grain filling stage, respectively, and were not obviously reduced compared to erect rice 9308 and semi-scattered rice M09.2. In seeding date experiment, as the seeding-date putting off, the growing degree days increased in a certain period, and the tiller angle of all the three genotype also increased when measured at the first time (27 days after seeding). However, the semi-scattered tillers of DI508 all changed to upright almost at 1650℃(GDD) in four seeding date treatments. From the first to the fourth seeding date, the accumulating rate of GDD and ontogenetic growing rate inceased, and the days of whole stage of rice decreased. Meanwhile, the total GDD from seeding date to maximum number of tiller and leaf of the three rice was almost 2250℃(GDD) in four seeding date treatments. In addition, DI508 showed out rapidly growing character in four seeding date treatments.3. In planting density experiment, it was showed that rice tiller angle was obviously affected by planting density. Rice tiller angle increased with planting density. At tillering stage, DI508 tiller angle of treatment I (15cm×15cm) was 14.54°larger than that of treatment VI (30cm×43cm). Meanwhile, the ontogeny of rice was affected by planting density. The weight of biomass and the number of tiller and leaves at low planting density were more than that of high planting density. In addition, in treantment II (20cm×25.7cm) DI508 showed out the most dry-weight of roots (g/cm3) in four planting densities.4. In the shading experiment, rice tille angle was significantly influenced by light density. The tiller angle of three rice varieties increased with falling of light density. The dynamic tiller angle of D1508 in two shading treatments was same to that of non-shading treatment (CK). At tillering stage, the average primary tiller angle of DI508 in the non-shading treatment was 10.75°and 16.25°less than that of 50% and 70%-shading treatment, respectively. Meanwhile, the ontogeny of D1508, such as the tiller number, dry-weight biomass and yield, decreased in shading treatmens. Therefore, the relationship between the ontogeny and the tiller angle affected by shading treatments needs to be studied in the future.
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