Estimation of Heterosis and Genetic Parameters in Maize for Cytoplasmic Male Sterility Lines using The Molecular Indicator RAPD

Abstract

This study aimed to evaluate number of pure inbred lines of maize (Zea mays L.) carried out for two seasons (spring and autumn) of 2019 in the fields of the research station / agricultural research station in Abo Gharib. Four cytoplasmic male sterile inbred lines (A1,A3,A5,A7) with their maintenance lines and four genetically fertile inbreds ( Inb2, HZ3, R5, 18) in addition to the control hybrid (Nahrain) were used. Single hybrids were produced according to line X tester system. All genotypes were planted using randomized complete block design (RCBD) in three replicate. Comparison results showed that inbred lines and their single crosses presented significant differences for all studied traits. The hybrids (A1 x HZ3), (A1 x R5) and (A3 x HZ3) scored highest yield (175.1, 172.2 and 172.1) respectively. The highest hybrid vigor values (65.97%, 63.22% and 45.33) were given by crosses (A1 x HZ3), (A1 x R5) and (A5 x HZ3) respectively. Obtained results also recorded significant influence of GCA and SCA in most studied traits, and showed that the average degree of dominance was more than one in addition to high value of broad sense heritability for all traits, on the other hand, the narrow sense heritability was low. RAPD technique was used to assess the genetic variability within studied lines of maize, eight out of ten primers produced 88 band at rate of 11 band per primer. Contrasting segments ranged between 3 for OPJ18 and 13 for OPF09 with molecular weight ranged between 200 – 2000 bp. The total number and percentage of contrast polymorphic pieces 64 and 72 .4% sequentially, the highest percentage of polymorphic pieces 81.3%, the highest efficiency is 18.2%, and the highest discriminating ability is 20.3% in the primers OPF09. The primers used were able to fingerprint for all inbreds under study. The results indicated that the RAPD parameters are highly efficient in diagnosing purity and genetic distance between maize inbreds.