College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China.
Current address: Plant Science, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK.
BMC Plant Biol. 2019 Nov 21;19(1):508. doi: 10.1186/s12870-019-2068-4.
Carbohydrate partitioning and utilization is a key determinant of growth rate and of yield in plants and crops. There are few studies on crops in field conditions. In Arabidopsis, starch accumulation in leaves is a negative indicator of growth rate.
Here, we wished to establish if starch accumulation in leaves could potentially be a marker for growth rate and yield in crops such as maize. We characterized daily patterns of non-structural carbohydrate (NSC) at different growth stages over two seasons for maize hybrids in the field. In 27 commercial hybrids, we found a significant negative relationship between residual starch in leaves and plant growth, but not with final yield and biomass. We then focused on three typical hybrids and established a method for calculation of C turnover in photosynthetic leaves that took into account photosynthesis, leaf area and NSC accumulation. The ratios of stored NSC decreased from approximately 15% to less than 4% with ongoing ontogeny changes from V7 to 28 days after pollination.
The proportion rather than absolute amount of carbon partitioned to starch in leaves at all stages of development related well with yield and biomass accumulation. It is proposed that screening plants at an early vegetative growth stage such as V7 for partitioning into storage may provide a prospective method for maize hybrid selection. Our study provides the basis for further validation as a screening tool for yield.
碳水化合物的分配和利用是植物和作物生长速度和产量的关键决定因素。在田间条件下对作物的研究很少。在拟南芥中，叶片中淀粉的积累是生长速度的负指标。
在这里，我们希望确定在玉米等作物中，叶片中淀粉的积累是否可能成为生长速度和产量的标志物。我们在田间对玉米杂种在两个季节的不同生长阶段的非结构性碳水化合物（NSC）日变化进行了特征描述。在 27 个商业杂种中，我们发现叶片中残留淀粉与植物生长呈显著负相关，但与最终产量和生物量无关。然后，我们专注于三个典型的杂种，并建立了一种用于计算光合叶片中 C 周转率的方法，该方法考虑了光合作用、叶面积和 NSC 积累。从 V7 到授粉后 28 天，随着从 V7 到 28 天的发育过程中形态发生变化，储存 NSC 的比例从大约 15%下降到小于 4%。
在发育的各个阶段，叶片中分配到淀粉的碳的比例而不是绝对量与产量和生物量积累密切相关。因此，在 V7 等早期营养生长阶段筛选向储存分配的植物可能为玉米杂种选择提供一种有前景的方法。我们的研究为进一步验证作为一种产量筛选工具提供了基础。
