استعمال التقنية الإحصائية للتحليل الوراثي بطريقتي (الفاحص في السلالة) والتبادلي الجزئي في تهجين الذرة الصفراء

Abstract

Afield experiment was carried out in field crops research station General Authority for Agricultural Research in Abu Ghraib in three successive seasons Spring and Autumn 2018 and Spring 2019. Eight inbred lines of maize (Zea mays L.) were used in the study (i.e., Sxn.22, MGW.11, lnb.17, Inb.23, O.7, Am.63, Zm.69 and S.17). In spring season eight inbred lines were crossed using to Line×Tester and partial diallel Cross method to produce 15 and 12 F1single crosses. The parents and single crosses were growing in Autumn season 2018 and spring 2019 in a comparison experiment using a randomize complete block design (R.C.B.D), with three rerplicates. The results showed significant differences amoing mean square of genotypes (parents+hybrids) for all studied traits for both methods and for Autumn and spring seasons except grains number per row trait in the partial diallel cross method for Autumn season. In the first method Line×Tester The inbred lines (Syn.22) and (O.7) gave highest mean grain yield per plant, with 159.63 and 127.63 g, respectively, for both Autumn and spring seasons. While the cross (MGW.11×Am.63) and (O.7×Zm.69) gave highest mean with exception grains number per row trait, where reached to 254.04 and 234.41 g for Autumn and spring season respectively. The cross (Am.63× MGW.11) in Autumn, and cross (Zm.69 × MGW.11) in the spring season gaved highest positive heterosis 75.68% and 93.74%, of the better parent for the grain yield per plant respectively. Also, the results of the genetic analysis in Autumn season showed highly significant differences for the mean square of genotypes (parents + crosses) for all studied traits except row number per ear, grains number per row and grain yield per plant were not significant for parents. row number per ear were significant for crosses. However, in the spring season the parents and crosses had a highly significant differences for all studied traits except row number per ear and grain yield per plant were not significant for parents. the parent line (syn.22) and (MGW.11) in Autumn and spring season had The highest GCA effects for grain yield per plant 15.03 and 23.15, respectively. The highest SCA effects were expressed in (Am.63×MGW.11) during Autumn season and in (Zm.69×O.7) during spring season for grain yield per plant 25.22 and 24.71, respectively. The variance ration of GCA was less than SCA in all studied traits except for both season. The broad sense heritability in Autumn season was high in all studied traits except, row number per ear and grains number per row were low. the ration was low values in spring season for all studied traits except ear length and grains number per row were high values, while grain yield per plant was medium. The Narrow sense heritability was low for all studied traits for both season. the over dominance gene was controlled on all studied traits for both season except ear number per plant there was no dominance because the average of dominance degree was zero. In partial diallel cross method, the crosses (S.17×O.7) and (Am.63×MGW.11) give highest mean for the grain yield per plant 252.80 and 220.49 g for both seasons, respectively. The crosses (MGW.11×Am.63) and (MGW.11×Zm.69) showed the highest heterosis in Autumn and spring seasons for grain yield per plant 73.41% and 85.33%. the mean square due two GCA and SCA were highly significant for all studied traits except for the grains number per row in ii GCA and plant height, leaf area, grains number per row, 250 grain weight and grain yield per plant in SCA were no significant. While in spring season the mean square due two GCA and SCA were highly significant for all studied traits except grains number per row wase no significant. the parent line (Am.63) and (MGW.11) in Autumn and spring seasons had The highest GCA effect for grain yield per plant 21.28 and 56.99 g, respectively. While the crosses (O.7×S.17) and (Am.63×MGW.11) in Autumn and spring seasons gave highest SCA effect grain yield per plant reached to 28.00 and 39.27 g, respectively. The variance ration of GCA was bigger than SCA in Autumn season for all studied traits except for the leaf area, ear number per plant, ear length and row number per ear. While in spring season the variance ration of GCA was largest than SCA for all studied traits except grains number per row. The broad sense heritability in Autumn and spring seasons was high values in all studied traits except row number per ear and grains number per row was medium in spring season. The Narrow sense heritability was high values for all studied traits for both seasons except days to 50% silking was low, and leaf area, row number per ear were medium in Autumn season, and grains number per row was medium in spring season. the over dominance gene was controlled on all studied traits for Autumn season except grain yield per plant was low, and days to 50% silking, ear height, ear length and 250 grain weight their values were zero, while the spring season did not appear any dominance in all studied traits because the values of zero, except grains number per row the value was largest than one. In genetic diversity, the results showed that the eight inbred line were grouped in to four different clusters by using cluster analysis for both season, the highest mean value for grain yield per plant 152.37 and 127.63g were observed in the cluster (I) and (II) for Autumn and spring season, respectively. the lowest value for genetic diversity observed between the parents (Inb.17) and (Inb.23) was 2.97 for the Autumn season, and between (O.7) and (S.17) was 2.81 for spring season. While the largest value was between the parents (Syn.22) and (Am.63) reached to 6.28 and 6.30 for Autumn and spring season. the largest inter-clauster distances was observed between clauster (II) and (III) for Autumn season, and clauster (I) and (IV) reached to 419.78 and 128.06, respectively. the largest inter-clauster distances was observed between clauster (I) and (III) for Autumn season, and clauster (III) and (IV) reached to 497.78 and 268.61, respectively for Line×Tester method. While in partial diallel cross method the largest inter-clauster distances was observed between clauster (II) and (III) for Autumn season, and clauster (I) and (II) reached to 363.25 and 267.25, respectively.