Key Laboratory of Crop Ecophysiology and Farming System in Southwest China, Ministry of Agriculture, Sichuan Agricultural University, Chengdu, PR China.
PLoS One. 2013 Jul 5;8(7):e68220. doi: 10.1371/journal.pone.0068220. Print 2013.
Rice is an important staple crop throughout the world, but environmental stress like low-light conditions can negatively impact crop yield and quality. Using pot experiments and field experiments, we studied the effects of shading on starch pasting viscosity and starch content with six rice varieties for three years, using the Rapid Visco Analyser to measure starch pasting viscosity. Shading at different growth stages and in different rice varieties all affected the starch pasting characteristics of rice. The effects of shading on starch pasting viscosity at middle and later growth stages were greater than those at earlier stages. Shading enhanced breakdown but reduced hold viscosity and setback at tillering-elongation stage. Most pasting parameters changed significantly with shading after elongation stage. Furthermore, the responses of different varieties to shading differed markedly. The change scope of starch pasting viscosity in Dexiang 4103 was rather small after heading, while that in IIyou 498 and Gangyou 906 was small before heading. We observed clear tendencies in peak viscosity, breakdown, and pasting temperature of the five rice varieties with shading in 2010 and 2011. Correlation analysis indicated that the rice amylose content was negatively correlated with breakdown, but was positively correlated with setback. Based on our results, IIyou 498, Gangyou 906, and Dexiang 4103 had higher shade endurance, making these varieties most suitable for high-quality rice cultivation in low-light regions.
水稻是全世界重要的主食作物，但环境胁迫如低光照条件会对作物产量和品质产生负面影响。我们使用盆栽实验和田间实验，在三年内用 Rapid Visco Analyser 测量淀粉糊化黏度，研究了不同遮阴处理对六个水稻品种淀粉糊化黏度和淀粉含量的影响。不同生长阶段和不同水稻品种的遮阴均会影响水稻的淀粉糊化特性。中期和后期生长阶段遮阴对淀粉糊化黏度的影响大于早期阶段。遮阴在分蘖-伸长阶段增加了崩解值，但降低了保持黏度和回冷值。伸长阶段后，大多数糊化参数随遮阴显著变化。此外，不同品种对遮阴的响应明显不同。在抽穗后，德香 4103 的淀粉糊化黏度变化范围较小，而在 IIyou 498 和 Gangyou 906 中则在抽穗前较小。我们观察到 2010 年和 2011 年五个水稻品种在遮阴下的峰值黏度、崩解值和糊化温度呈现出明显的趋势。相关分析表明，水稻直链淀粉含量与崩解值呈负相关，与回冷值呈正相关。基于我们的结果，IIyou 498、Gangyou 906 和德香 4103 具有较高的耐阴能力，使其最适合在低光照地区种植优质水稻。
