Xiao-Gui Liang1,2, Zhen Gao1, Li Zhang1, Si Shen1, Xue Zhao1, Yun-Peng Liu1,3, Li-Li Zhou1, Matthew J Paul4, Shun-Li Zhou5,6. 1. College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China. 2. Current address: Plant Science, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK. 3. School of Bioengineering, Binzhou University, Binzhou, 256600, Shandong, China. 4. Current address: Plant Science, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK. matthew.paul@rothamsted.ac.uk. 5. College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China. zhoushl@cau.edu.cn. 6. Scientific Observation and Experimental Station of Crop High Efficient Use of Water in Wuqiao , The Ministry of Agriculture and Rural Affairs, Wuqiao, 061802, China. zhoushl@cau.edu.cn.
Abstract
BACKGROUND: 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. RESULTS: 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. CONCLUSION: 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.
BACKGROUND: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. RESULTS: 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. CONCLUSION: 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.