两系粳杂双晚超稀播壮秧的分蘖穗型质量研究初报

Preliminary Studies on the Panicle Quality of Tillers from Strong Seedlings under Super-sparsely Seeding for Late-cropping Two-line Japonica Hybrid Rice

播量、穴栽插本数、分蘖发生时期、植伤诸因素均显著影响穗型质量，分蘖发生时期最为突出。一次分蘖节位、二次分蘖见蘖期分别与穗总粒数、穗粒重显著相关，随着分蘖节位每升高１个和见蘖期推迟３ｄ，穗总粒数减少７．６６～２１．７１粒；穗粒重降低０．１５～０．４１ｇ。综合粒、重等因素，穗质量为主茎＞第１节位分蘖＞秧田期一次分蘖＞本田一次分蘖＞二次分蘖。提高穗质量除稀播培育多蘖壮秧外，要以促进低节位分蘖和同伸的二次分蘖早生快发为重点。

The panicle quality was affected by the amount of sowing, the number of transplanted seedlings per hill, the injure of transplanting, especially the tillering time. There was a significant correlation between the primary tiller position, secondary tiller stage and spikelets per panicle, the 1 000-grain weight with tiller position one node higher and tillering stage 3 days later, the number of spikelets per panicle decreased by 7.66～21.71, the 1 000-grain weight decreased by 0.15～0.41 g. Based on the comprehensive performance of panicle characters, the panicle quality of tillers (or main culm) is main culm>lst nodal tillers>primary tillers of seedling bed>primary tillers of main field>secondary tillers. It is concluded that to raise panicle quality, it is important to promote the early generating of lower nodal primary tillers and their secondary tillers, to inhibit the occurrance of high nodal (>9) primary tillers and their secondary tillers through appropriate cultural practices.