以旱育中秧龄抛秧、旱床育秧移栽、水育秧移栽为对照，对水稻旱长秧龄抛秧栽培生物学特性及其技术进行了研究。结果表明：旱育长秧龄抛秧N，P，K吸收和干物质积累量大，前期、中期生长优势明显，单位面积容纳的穗数与颖花多，后期根系生长量大，氧化活力强，土壤表层0～7 cm分布比例高，根/冠值大，齐穗期稻株中、下部透光率高，但生育进度较移栽慢；增加中、后期氮肥施用比例及适当加大抛栽密度，有利于叶面积扩展及干物质积累，形成更多的有效穗数，提高产量。本研究认为，适当增大抛栽密度，减少前期施氮量，提高中、后期用氮比例，是提高旱育长秧龄抛秧产量的重要农艺对策。%Biological characters and the practice of dryland－raised long－age seeding associated with scattered－planting in rice, in contrast with dryland－raised middle－age seedling associated with scattered－planting, dryland－raised manual－planting, paddy－raised manual－planting were studied. The results were as follows: Its absorption of N,P,K and accumulations of dry matter were rich, while demonstrating the growth dominance of the early and middle stage, and the panicles and spikelets per unit area were richer, the root system was larger than those of the control, while its root activity was stronger, the ratio of root system at 0～7cm was larger, and root/shoot was higher, the light penetrating ratio of the middle and low part at the fullheading stage were higher, but its growth and development process was slower than that of the manual. Increasing N application at middle and later stage and hightening scattering density appropriately could amplify leaf area index,increase absorption of N，P，K and accumulation of dry matter, promote formation of more bearing panicles and improve yield. Increasing density, reducing the rate of N application at early growth stage and raising the rate of N application at middle and later growth stage were the suitable agronomic strategy for this kind of practice.
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