Screening of maize inbred lines and evaluation of hybrids for their resistance to fall armyworm

Abstract

Maize yield losses due to fall armyworm (FAW) infestation is in the range of 22–67%, amounting to millions of US dollars in sub-Saharan Africa (SSA). Identifying new sources of maize genotypes with resistance to insects and a better understanding of resistance mechanisms have opened the avenue for the exploration of host-plant resistance (HPR). The present study was carried out to assess the resistance of maize inbred lines and hybrids to FAW foliar feeding damage through natural and artificial screening. Thirty-five (35) maize inbred lines obtained from the International Maize and Wheat Improvement center (CIMMYT) and the United State Department of Agriculture – Agricultural Research Services (USDA–ARS) were screened for fall armyworm resistance in Ghana in 2019. In addition, sixty (60) single-cross hybrids and twenty (20) double-crosses developed from 17 desirable inbred lines were evaluated for resistance to fall armyworm using artificial and natural infestations in 2020 and 2021. Significant differences were recorded among the inbred lines, F1 hybrids, and the double-crosses. The cluster and principal component analysis classified the thirty-five inbred lines into four groups suggesting the presence of wide variability. Hybrids (CML343*CML 346)//(CML124*MP 713), (MP713*MP705)//(CML123*MP713), (CML331*MP701)//(MP702*MP705), (CML330*MP702)//(CML123*MP706), (CML122*MP713)//(CML330*MP701), (OBT*MP708)//(MP713*MP705),MP704*CML122)//(CML123*MP713), (CML123*MP708)//(CML122*MP713) and (CML330*MP701)//(MP713*MP705) were found to be promising. These hybrids should be recommended for further testing and commercialization in SSA.