开花期施磷对青海扁茎早熟禾种子产量及繁殖分配的影响

Effect of Phosphorus Addition on Seed Yield and Reproductive Allocation of Poa pratensis var.anceps Gaud.cv.Qinghai at Flowering Stage

以5龄青海扁茎早熟禾(Poa pratensis var.anceps Gaud.cv.Qinghai)为研究对象,在开花期进行不同梯度磷添加试验,探讨施磷对其种子产量的影响。结果表明:通过开花期施磷,增加了穗干物质转运和穗部生物量,进而提高青海扁茎早熟禾种子产量(3%~28%)。施磷量在60kg/hm 2(P2)时,种子产量达到最大,为255.08kg/hm 2。开花期施磷显著影响青海扁茎早熟禾繁殖分配,施磷量在P2时,繁殖分配达到最大,为5.47%。建植5年的青海扁茎早熟禾在繁殖策略上倾向于用根茎进行无性繁殖。因此,试验区域种子生产最佳施磷(P 2O 5)梯度为60kg/hm 2,以提高种子产量和繁殖分配,为高寒地区根茎型牧草种子增产稳产和合理施肥提供理论依据。

Taking 5-year-old Poa pratensis var.anceps Gaud.cv.Qinghai as the research object,the gradient phosphorus addition experiment was carried out at the flowering stage to explore the effect of phosphorus addition on its seed yield.The results showed that the phosphorus addition at flowering stage increased the seed yield by 3%~28%by increasing the dry matter transport and biomass of panicle.The maximum seed yield was 255.08kg/hm 2 when the phosphorus addition was 60 kg/hm 2(P2).The phosphorus addition at flowering stage significantly affected the reproductive allocation of Poa pratensis var.anceps Gaud.cv.Qinghai.The maximum reproductive allocation was 5.47%at P2.In terms of reproductive strategy,the 5-year-old Poa pratensis var.anceps Gaud.cv.Qinghai tended to reproduce asexually by rhizome.Therefore,in the experimental area,the optimum phosphorus addition concentration was 60kg/hm 2(P2),which can improve the seed yield and reproductive allocation,and provide a theoretical basis for increasing the yield of rhizomatous forage seeds and reasonable fertilization in alpine region.