Genotypic variation in grain P loading across diverse rice growing environments and implications for field P balances

Frontiers in Plant Science

卷:7

Mamadou Fofana¹  Ramaiah Venuprasad¹  Kazuki Saito²  Elke Vandamme²  Kalimuthu Senthilkumar²  Khady Nani Drame²  Ibnou Dieng²  Zacharie Segda³  Yoichiro Kato⁴  Matthias Wissuwa⁵  Demba Jallow⁶  Dinarathna Sirisena⁷  Terry Rose⁸  Lalith Suriyagoda⁹ 

[1] Africa Rice Center, C/o IITA;

[2] Africa Rice Center;

[3] CNRST/INERA;

[4] International Rice Research Institute;

[5] Japan International Research Centre for Agricultural Science;

[6] National Agricultural Research Institute (NARI), Brikama Head Quarters;

[7] Rice Research and Development Institute;

[8] Southern Cross University;

[9] University of Peradeniya;

关键词: Rice genotypes;    P utilization efficiency;    P cycling;    P removal;    Grain P concentration;   

DOI  :  10.3389/fpls.2016.01435

来源: DOAJ

【 摘 要 】

More than 60% of phosphorus (P) taken up by rice (Oryza spp) is accumulated in the grains at harvest and hence exported from fields, leading to a continuous removal of P. If P removed from fields is not replaced by P inputs then soil P stocks decline, with consequences for subsequent crops. Breeding rice genotypes with a low concentration of P in the grains could be a strategy to reduce maintenance fertilizer needs and slow soil P depletion in low input systems. This study aimed to assess variation in grain P concentrations among rice genotypes across diverse environments and evaluate the implications for field P balances at various grain yield levels. Multi-location screening experiments were conducted at different sites across Africa and Asia and yield components and grain P concentrations were determined at harvest. Genotypic variation in grain P concentration was evaluated while considering differences in P supply and grain yield using cluster analysis to group environments and boundary line analysis to determine minimum grain P concentrations at various yield levels. Average grain P concentrations across genotypes varied almost 3-fold among environments, from 1.4 to 3.9 mg g-1. Minimum grain P concentrations associated with grain yields of 150, 300 and 500 g m-2 varied between 1.2 and 1.7, 1.3 and 1.8 and 1.7 and 2.2 mg g-1 among genotypes respectively. Two genotypes, Santhi Sufaid and DJ123, were identified as potential donors for low grain P concentration. Improvements in P balances that could be achieved by exploiting this genotypic variation are in the range of less than 0.10 g P m-2 (1 kg P ha-1) in low yielding systems, and 0.15 to 0.50 g P m-2 (1.5-5.0 kg P ha-1) in higher yielding systems. Improved crop management and alternative breeding approaches may be required to achieve larger reductions in grain P concentrations in rice.

【 授权许可】

Unknown