Grey Relational Analysis and Path Analysis on Wheat Yield and Its Three Key Factors

Abstract：Wheat cultivated varieties which plant area were in top 15 in Henan province or performed better in regional and productive experiments from 2008 to 2014 were chosed for this experiment. The relationship between wheat spikes, grain numbers per spike, thousand-grain weight and yield were analyzed by grey relational analysis and path analysis, and the difference between two analysis methods were compared for providing reference for method choosing in related studies in the future. The results showed that the correlation degree between yield and its three key factors were different when the primary data was processed through initialization, interval and equalization, the correlation degree orders were thousand-grain weight > grain numbers per spike > spikes number, grain numbers per spike > spikes number> thousand-grain weight, grain numbers per spike > thousand-grain weight > spikes number, respectively. While the result obtained through path analysis were more similar with former studies, the relationship between yield and its key factors was spikes number>grain numbers per spike>thousand-grain weight. The result indicated that experimental result obtained from grey relational analysis was much more variable than that from path analysis due to the influence of different primary data processing methods. In conclusion, the path analysis should be chosen as the main method for analyzing the correlation among different experimental factors.