杂交稻天优3301再生高产的产量构成及其调控

High-yielding Components and Their Regulation in Regenerative Production of Hybrid Rice Tianyou 3301

为查明天优3301再生稻高产的产量构成及其调控途径，2007、2008年在福建省尤溪县设置分期播栽试验，调查不同产量水平的产量构成，结果表明，天优3301从头季播种至再生季抽穗的积温为4000℃；早播早栽田头季显著延长营养生长期，结实期与光温高值期重合，再生季在安全齐穗期前抽穗，有利于建成多穗大穗、高结实率的群体；早播早栽田决定产量的主要构成因素是穗数和每穗粒数，二者对产量提升的贡献率合占95％以上，其中头季以每穗粒数对增产的贡献率最高，再生季以穗数对增产的贡献率最高；迟栽迟播田头季结实期寡照，再生季花期和结实期遇冷害频繁，最终结实率低限制了高产。天优3301作再生稻栽培，宜早播早栽、适当密植；头季高产须在形成足额穗数基础上，主攻大穗；再生季高产的关键是促进腋芽萌发，形成比头季多70％～100％的穗数。

In order to find out the high - yielding components and their regulation in regenerative production of hybrid rice Tianyou 3301, interval sowing experiments were carried out, and yield components at different yield levels were investigated in Youxi county of Fujian province in 2007 - 2008. The results indicated that the accumulative temperature from the sowing of main rice to the heading of regenerative rice of Tianyou 3301 was 4000℃. Under the condition of early sowing and early transplanting, the vegetative growth stage of main rice was prolonged obviously, its setting stage overlapped with the high - value period of light and temperature, and the regenerative rice could safely tassel, which was beneficial for the formation of population with many and large spikes and high setting rate. In early sowing and early transplanting field, the main yield components were the number of spike and grains per spike, and their contribution rate to yield formation was up to 95%. The contribution rate of grains per spike in main rice and the number of spike in regenerative rice to yield increase was the highest. In late sowing and late transplanting field, the scant light in ripening period of main rice and chilling injury in flowering and ripening period of regenerative rice resulted in low setting percentage and low yield. When Tianyou 3301 was planted as regenerative rice, it should be sowed and transplanted early with rational planting density. The key to realize high yield of main rice was large spike on the basis of adequate spikes, and the key to obtain high yield of regenerative rice was to promote the germination of auxiliary buds in order to form 170% - 200% more spikes than the main rice.