Abstract: Based on the experiments and the plant population growth types development and evolution theory, this paper analyzed the natural phenomenon of the corn hybrid characters improvement during 30 yesrs from early 1960's to early 1990's in Hebei-Shandong-Henan summer corn planting zone. The study indicated the evolution ways of corn hybrid population growth types relied on continuous improvement of the yield, spotted diseases and lodging resistance. During the past 30 years, maximum grain yield of single plant increased 48.4%. The leaf spotindex, lodging and stem broken rates reduced 4.3% and 1.2% respectively. The evolution process can be divided into four stages. The four stages and their associated representing corn hybrid are:1.1960's Xindan 1 and Baidan4|2.early 1970's,Qundan 105 and Danyu6;3.late 1970's to the beginning of 1980's, Zhengdan 2 and Bodan I;4.early 1980's to. early 1990's, Yandan 14 and Yedan2. The hybrid population growth types evolution followed the organic evolution law, that is "forming groups by multi-species dynamic metabolization, getting rid of the stale and taking in the fresh, developing in an orderly way arid step by step".

Key words: Hebei-Shandong-Henan summer corn planting zone, Corn hybrid, Population growth types, Evolution, Evolution stages, Evolution basic ways

CLC Number: 

• S513.01