| The main goal of wheat breeding is to adapt to the climatic change and develop new wheat vultivars with high yield. Recently, by improving the plant architecture, and increasing of resistance and index of harvest, the yield of wheat was significantly increased. Therefore, further improvement of wheat yield is becoming harder and harder. Facing the climatic change, how to improve the temperature production efficiency in wheat and the yield has become a hot topic for research workers.Using statistic methods such as regression analysis and cluster analysis, we analyzed the relationship between both photosynthetic and temperature production efficiency characters and yield, based on recombinant inbred lines populations for Neixiang188/Yanzhan No.1under multiple environments and important agronomic traits. The relevance between wheat temperature production efficiency characters and biology characters was clarified, and the theoretical basis in selective breeding of wheat high photosynthetic and temperature production efficiency was also presented. Meanwhile, molecular marker-assisted selection has been used to in breeding the wheat new varieties.1. Results showed that there was a positive correlation between P&TPE and spikes per plant, grain number per spike, plant height, average filling rate, the maximum filling rate of wheat. The correlation level between spikes per plant and P&TPE is the highest, and that of the grain number per spike is less. We believe that wheat high P&TPE have7million spikes per unit area,35%above in average grain number per spike and filling rate per thousand grain number>1.5g/d.2. Previous studies showed that loci which affected photosynthetic-thermal efficiency located on12chromosomes(1D,2A,2B,2D,3A,3B,4B,5A,6A,6D,7A and7B).Molecular markers wmc474, barc218and Xwmc327-Xbarc56(located on chromosome2A,3A and short arm of5A, respectively) played an important role in photosynthetic-thermal efficiency. We detected15QTL loci related to photosynthetic-thermal efficiency under five environments by QTL analysis. Each QTL can account for13-35%of phenotypic variation. The QTL loci located on chromosome2A,3A,1D and4B were associated with photosynthetic efficiency and thermal efficiency simultaneously. QTLs near Wmc474(located on chromosome2A) and barc218(located on chromosome3A) were repeated detected under two environments and contributed great in photosynthetic-thermal efficiency. Using RILs derived from Yanzhanl and Neixiang188, association analysis was conducted based on405molecular markers. We found that Xwmc327-Xbarc56which located on short arm of5A showed significant correlation with photosynthetic-thermal efficiency, it affected spike length and yields as well.3. Researches showed that wheat variety with high P&TPE can highly utilize P&T resource in spring and winter, and increase the tiller number and spikes. Zhongjiao No.1(ZJ1) with high P&TPE has high ability of tiller number and spike rate. Under the same density of planting, the tiller number is higher415million/ha than Yumai49(YM49), by23.3%. Under the deficient photosynthetic and heat resource,213m/ha, by16.9%. The spike of ZJ1is significantly higher than Zhongjiao no.2(ZJ2) and YM49wtih1,04M/ha (17.8%) and0.77M/ha (12.6%), respectively. Under the deficient photosynthetic and temperature, the spike of Zhongjiao No.l has5.97m/ha, which is higher than other two varieties by31.0%and16.1%.4. Studies showed that the varieties with high P&TPE had strong adaptability and fast filling rate. Zhongjiao No.1is not as fast as Yumai49before one week of filling. But along with the increasing temperature, filling rate increases rapidly. Both the maximal and average filling rate are higher than Yumai49. The average filling rate of Zhongjiao No.l is higher than Yumai49by13.56%. The maximal rate arrives12.7%.5. Researches indicated that the varieties of H-P&TPE could adapt recent climatic change and obtain a high wheat yield. Zhongjiao No.1deriving from NY RIL had high-yield and H-P&TPE properties. Increased yield by5%, photosynthetic production efficiency (PPE) by9%and10.7%, and temperature production efficiency (TPE) by11%and13.5%than Zhongjiao2and Yumai49respectively, and the difference reached a very significant level.6. Studies showed that H-P&TPE wheat varieties need less P&T resources can obtain a higher yield, it, is in response to the special climatic conditions and specific cultivation mode advantage, fully embodies the varieties characteristics of H-P&T, and provide technical support to ensure that food production. |
PDF Full Text Request