氮肥运筹与栽插密度对粳稻颖花和产量形成的影响

Effects of nitrogen managements and transplanting density on spikelets and yield formation of japonicarice varieties

以大穗型杂交粳稻甬优1538和常规粳稻新品种(系)苏12-130为材料,研究不同氮肥运筹和栽插密度对不同穗型粳稻颖花和产量形成的影响。结果表明:与8∶2的基蘖肥、穗肥比相比,6∶4的基蘖肥、穗肥比显著提高穗粒数、千粒重和籽粒产量,甬优1538在栽插密度16.5cm×30.0cm、苏12-130在栽插密度13.2cm×30.0cm条件下产量显著高于其他处理。增施穗肥显著降低每穗颖花退化数,增加每穗颖花现存数;随着栽插密度变小,甬优1538每穗枝梗数和颖花数分化和现存数显著增加,退化数显著降低,苏12-130显著增加每穗颖花现存数。不同处理的2个品种一次颖花分化及退化无显著差异,而二次颖花退化数和现存数的影响均达到显著水平。着生在每穗下部的二次颖花分化与退化受氮肥运筹和栽插密度的影响较中部和上部大,增施穗肥和栽插增大密度变小使2个品种每穗总颖花现存数显著增加的主要原因是促进中、下部二次颖花分化,并减少退化数。

With a hybrid japonica rice variety with large panicle Yongyou 1538 and a traditional japonica rice variety （line） Su 12-130 as materials, the effects of nitrogen managements （the basic and tiller fertilizer to the panicle fertilizer of 6 ： 4 and 8 ： 2） and transplanting density（13.2 cm）〈30.0 cm, 16.5 cmX30.0 cm and 20.0 cmX30.0 em） were investi- gated on spikelets and yield formation of japonica rice varieties with different panicle types. Compared with the basic and tiller fertilizer to the panicle fertilizer of 8 ： 2, the grains per spike, 1000-grain weight and yield significantly increased under the treatment of the basic and tiller fertilizer to the panicle fertilizer of 6 ： 4. The yield of Yongyou 1 538 under the transplanting density of 16.5 cmX 30.0 era, Su 12-130 under the transplanting density of 13.2 crux 30.0 cm were signifi- cantly higher than other transplanting density treatments. More panicle fertilizer could significantly decrease the retrogra- ded spikelets per panicle and increase the survived spikelets per panicle. With the transplanting density decreased, the dif- ferentiated and survived number of branches and spikelets per panicle of Yongyou 1538 and the survived number of spike- lets per panicle of Su 12-130 increased significantly. Under the different treatments, there was no significant difference in the differentiated and retrograded spikelets on primary branches of two varieties, but significant difference in the retrogra- ded and survived spikelets on secondary branches. The nitrogen managements and transplanting density treatments affect ed more greatly the differentiation and degradation of spikelets on secondary branches at the basal part of a panicle than at the middle and upper of a panicle. The main reason that increasing the panicle fertilizer and decreasing transplanting density could increase the survived spikelets per panicle of two varieties was to promote the differentiation of spikelets on secondary branches at the middle and basal part of a panicle, and decrease the number of degradation.