Evaluation Of The Breeding Potential Of 11 South American Population-modified Maize Combination DN98 × R1

The excellent corn combination DN98 × R1,as a type of corn for both grain and feed,has been planted for many years in production and has the advantages of high yield and strong adaptability,but it also has the disadvantages of long growth period,general resistance,and high water content at harvest.This article cites 11 South American populations to improve the main shortcomings of DN98 × R1.This experiment adopted a split-plot design.In Wuhan in the autumn of 2020,two test species(female parent),DN98 and R1,were combined with 11 populations(male parent)to form two groups of 22 top cross combinations.In the winter of 2020 in Hainan,two test species were combined with the top cross combination with 22 triple cross combinations and controls.In the autumn of 2021,a three-location yield joint identification test will be conducted in Xingshan County,Hubei Province.According to the genetic parameters proposed by Dudley et al.,the improvement potential of the11 populations to the maize combination DN98 × R1 was evaluated,and the valuable donor combinations were screened to achieve the purpose of improving the excellent maize combination DN98 × R1.The main conclusions of this experiment are as follows:1.22 top-cross seed combinations,in terms of yield,only D4(DN98×(Tupeno ×Comiteco)H)and M4(R1×(Tupeno × Comiteco)H)significantly increased yield compared with the control,while other combinations all decreased significantly;In terms of improvement direction,no combination was better than the control without significant yield reduction;in terms of resistance,leaf disease was serious,and no top-cross combination was resistant to both gray spot and small spot disease.2.In terms of yield,D4(DN98×(Tupeno × Comiteco)H)×R1 has a significant increase in yield compared with CK,and there are four combinations that exceed the control,but the difference is not significant;D4(DN98×(Tupeno × Comiteco)H)×R1 has good performance in the two main improvement directions of water content at harvest and growth period;M11(Winter 2014,Mobai 962 mixed with V-2-1)× DN98,M3(R1 × PA2911.Co AH25,Raton-Naltel)× DN98 had good performance in water content at harvest,M8(R1 × URZM 13085)× DN98 had good performance in growth period;in terms of resistance,the three-cross combination leaf disease was basically the same as the control.flat.3.Population K3(PA2911.Co AH25,Raton-Naltel)has great potential in reducing plant height,but its yield is significantly reduced;K4(Tupeno × Comiteco)H))has great potential in improving yield.