Liu Yang, Gu Dandan, Wu Wei, Wen Xiaoxia, Liao Yuncheng
College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China.
PLoS One. 2013 Oct 29;8(10):e78196. doi: 10.1371/journal.pone.0078196. eCollection 2013.
The grain weight of wheat is strongly influenced by filling. Polyamines (PA) are involved in regulating plant growth. However, the effects of PA on wheat grain filling and its mechanism of action are unclear. The objective of the present study was to investigate the relationship between PAs and hormones in the regulation of wheat grain filling. Three PAs, spermidine (Spd), spermine (Spm), and putrescine (Put), were exogenously applied, and the grain filling characteristics and changes in endogenous PA and hormones, i.e., indole-3-acetic acid (IAA), zeatin (Z) + zeatin riboside (ZR), abscisic acid (ABA), ethylene (ETH) and gibberellin 1+4 (GAs), were quantified during wheat grain filling. Exogenous applications of Spd and Spm significantly increased the grain filling rate and weight, but exogenous Put had no significant effects on these measures. Exogenous Spd and Spm significantly increased the endogenous Spd, Spm, Z+ZR, ABA, and IAA contents and significantly decreased ETH evolution in grains. The endogenous Spd, Spm and Z+ZR contents were positively and significantly correlated with the grain filling rate and weight of wheat, and the endogenous ETH evolution was negatively and significantly correlated with the wheat grain filling rate and weight. Based upon these results, we concluded that PAs were involved in the balance of hormones that regulated the grain filling of wheat.
小麦粒重受灌浆过程的强烈影响。多胺（PA）参与调节植物生长。然而，PA对小麦籽粒灌浆的影响及其作用机制尚不清楚。本研究的目的是探讨PA与激素在调控小麦籽粒灌浆中的关系。外源施加三种多胺，即亚精胺（Spd）、精胺（Spm）和腐胺（Put），并对小麦籽粒灌浆特性以及内源PA和激素（即吲哚-3-乙酸（IAA）、玉米素（Z）+玉米素核苷（ZR）、脱落酸（ABA）、乙烯（ETH）和赤霉素1+4（GAs））的变化进行了定量分析。外源施加Spd和Spm显著提高了籽粒灌浆速率和粒重，但外源Put对这些指标没有显著影响。外源Spd和Spm显著提高了籽粒内源Spd、Spm、Z+ZR、ABA和IAA的含量，并显著降低了籽粒中ETH的释放量。内源Spd、Spm和Z+ZR的含量与小麦籽粒灌浆速率和粒重呈显著正相关，而内源ETH的释放量与小麦籽粒灌浆速率和粒重呈显著负相关。基于这些结果，我们得出结论：多胺参与了调控小麦籽粒灌浆的激素平衡。
