Excellent Selection And Program Optimization Of Apple Progenies At The Macro-population Level

Apple breeding is the foundation of the development of apple industry.The conventional hybridization breeding is the main approach.Though modern biotechnology develops rapidly,field experience in breeding is still the most efficient method.In attempt to obtain a varity which could be expanded widely,improving hybrid population has become the consensus of hybridologists at home and abroad.Guided by this principle,huge hybrid popolation result in enormous difficulties in mangagement and breeding.It is necessary to solve this issue of how to optimize the breeding procedure to raise the efficiency of breeding.This study combined with the breeding experience on the basis of “large population”ideas and then we conclude the experience of screening of improved breeds and optimization of breeding procedure.1.Early selection could be finished in three or four years.Early selection mainly choose plant type,agronomic trait,disease resistance etc as indicators and and its eliminating ratio was at about 60%,the ratio of the elimination on early selection of Fuji,pink lady and Qinguan crosses were averaged for 67.46% and 68.33% respectively.2.Secondary selection make fruit character as the main index,observe it in two or three consecutive years and preconcerted selection intensity was 80%-90%.The average of elimination rate were 83.75% and 91.82% in the cross combination Fuji,pink lady and Qinguan.3.A hybrid combination of breeding will cost 15 to 20 years according to common procedure of crossbreeding.The age of breeding shortened to about 12-13 years combined with our breeding practice.In this process,cross pollination take a year,early selection consume three or four years,next,primary selection and secondary selection cost two years respectively,and then final selection,regional trial need three or four years,lastly,approval was finished in one year.4.In the aspect of program optimization,using the greenhouse seedling technique;the technique of M26 high-grafting;Primary election to the "inferior election" as the principle,Secondary selection with the ‘Optimal Selection' principle;Determine the scope of the each screening stage elimination rate,increase the elimination rate.Final selection and regional testsimultaneously,can shorten the breeding period 3 to 7 years.