Where Is Way out of Crop Crossing Breeding?

Author discussed a series of guiding principles for scientific crossing breeding in future. This paper advanced firstly “Original theory of crop science”, “Net system of genetic character of variety yield performance of crops”. Stressfully expounded its core concept, variety yield performance; basic contradiction between variety adaptability and yield ability; ecology theory of variety suitable-stable ability; theory of yield ability science; plant type trait and plant type theory. A brief introduced this original theory obtained approval, evaluation and great significance in international academic circles. Author was on the basis of original theory in breeding practice bring forth new ideas of breeding and obtained outstanding effect, breeding efficiency increased more than four times. Raised some new concepts concerning genetics and breeding science, for example: each other action between suitability and yield ability (character), closed and open breeding (point out: Open nature of sexual crossing breeding decided it will always have a losing, not foothold and any breeding way all cannot replace it), ecology of crop variety, theoretical genetics and breeding science of crops, etc. In the end, raised transformation present experience breeding into scientific breeding being aimed at difficult problems in experience breeding under leading of original theory and arousing of reformation breeding practice, and objective, assignment, technology key and route, engineer-technology system. Relationship between sexual crossing breeding and transforming gene breeding was also discussed.