Two strategies for achieving higher yield under phosphorus deficiency in winter wheat grown in field conditions
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- 作者：Lanzhen Wang ; Fanjun Chen ; Fusuo Zhang ; Guohua Mi
- 关键词：Winter wheat (Triticum aestivum L.) ; Yield structure ; Low-P stress ; Tiller ; Floret ; P efficiency
- 刊名：Field Crops Research
- 出版年：2010
- 出版时间：6 July 2010
- 年：2010
- 卷：118
- 期：1
- 页码：36-42
- 全文大小：400 K
文摘
Under field conditions, phosphorus (P) deficiency reduces wheat yield by affecting different yield components. However, the physiological strategies by which wheat genotypes with different yield structures respond to low-P stress are not clear. In the present study, we investigated tiller, floret, and root biomass, and P uptake and remobilization at two levels of P under field conditions in three winter wheat genotypes with different yield structures and P-efficiencies. Results showed that P-efficient cultivars CA9325 and ND139 got higher yield and total P accumulation than P-inefficient ND3291 at low-P, but not at normal P treatment. However, both the P-efficient wheat cultivars tend to have the same advantageous yield components at both high P and low-P stress. CA9325, a large-eared genotype, developed more fertile florets, and therefore had more grains at low-P stress. Increasing the number of grains formed a large sink for P demand during the grain-filling stage. Correspondingly, this genotype developed large roots for sustaining post-anthesis P uptake. ND139, a multi-eared genotype, developed many more tillers at low-P stress, and formed more ears at maturity. P from infertile tillers was probably reutilized by the surviving tillers to ensure floret development. Correspondingly, the contribution of pre-anthesis P uptake in ND139 and subsequent remobilization of P to the grains was higher. It was found that larger root rather than higher root activity was the determinant factor in efficient pre-anthesis P uptake in ND3291 and efficient post-anthesis P uptake in CA9325. It is concluded that increasing wheat yield at low soil P availability can be realized by either increasing ears per plant or increasing grains per ear through crop management or breeding.