Keywords : Inbred lines


Estimation of Genetic Diversity among Inbred lines and Single Hybrids of Maize (Zea mays L.)

A. M. Ahmed; A. H. A. Sweed

ANBAR JOURNAL OF AGRICULTURAL SCIENCES, 2017, Volume 15, Issue 1, Pages 71-82
DOI: 10.32649/aagrs.2017.129075

Six inbred lines (1-S10, 2-Zn12, 3-Sy24, 4-Zm17, 5-O18, 6-Mgw7) of maize were crossed in half diallel to produce 15 single cross in Field Crops Research–Abu Ghraib in fall season 2014. Seeds of genotypes (6 lines +15 single cross) have been planted in field of a farmer in Abu-Ghraib, using randomized complete block design (R.C.B.D), with three replicates in fall season of 2015, to evaluate the performance of these lines and hybrids and to estimate genetic diversity among 6 lines and 15 single cross by using Mahalanobis D2 statistic for 10 morphological traits Viz. days to silking, plant height, ear height, leaves number, leaf area, ear number per plant, ear length, rows number per ear, 250-kernel weight and yield kernel per plant.
Statistical analysis showed significant variation among maize genotypes for all studied traits. The six inbred lines were grouped into three different clusters by using cluster analysis. The cluster I contained the highest number of lines 1, 2, 5 cluster II contained towlines 3 and 4 and cluster III contained one line 6. The highest ‎mean values for all traits, which, in clouding grain yield per plant about 146g ‎were observed in cluster III, except ear height with 69.83 cm, and the lowest ‎mean value for days to 50% silking as 61.50 day were found in cluster II. The inter-cluster distances were larger than intra-cluster distances, ‎suggesting wider genetic diversity among the lines of different groups. ‎The highest inter-cluster distance was observed between cluster I and ‎cluster III with 6.49, and lowest between cluster II and cluster III with 3.85. The highest intra-cluster distance was noticed in ‎cluster I as 3.3%. and lowest for cluster III. Fifteen hybrids were grouped into six clusters, The ‎cluster I contained the highest number of hybrids 1, 2, 3, 4, 5, 6, 9, 10 and 11 cluster II, III, V, and VI contained one hybrid for each one 7, 8, 13 and 15 respectively, while cluster IV contained tow hybrids 21 and 14. The highest mean ‎values for plant height, leaves number per plant, leaf area, ear length, rows number per ear by17.34, 250-kemel weight with 65.00 g and grain yield per plant as 174.17 g ‎were observed in the cluster IV.
The mean of ear height with 82.33cm was the highest in cluster II and the mean highest for number of ears per plant about 1.30 was the highest in cluster VI. The lowest mean value for days to silking with 58.00 day was found in cluster V and cluster VI. The inter cluster distances were larger ‎than intra-cluster distances, suggesting wider genetic diversity among the hybrids of different groups. The highest inter-cluster distance was ‎observed between cluster IV and cluster VI with 7.03, and the Lowest between cluster I and cluster II about 3.54. The highest ‎intra-cluster distance was noticed in cluster I abut 3.76.

Genetic Analysis for Combining Ability and Estimation some Genetic Parameters for Inbred lines and Single Cross Hybrids of Maize

Nasser M. Al-Amery; Hashem R.Latheth; Abed M. Ahmed

ANBAR JOURNAL OF AGRICULTURAL SCIENCES, 2016, Volume 14, Issue 1, Pages 155-162

Six inbred lines of maize have been used (1- Syn-1, 2-MGW-3,3- S-165,4-Syn-22,5- Zm-9,6- M-17) entered in program were crossed in half diallel cross to produce 15 F1 cross in Field Crops Research Station of General Board Agricultural Research, Abu-Ghraib in fall season 2013. Seeds of genotypes (6 parents and 15 cross) have been planted in field of a farmer in Almusaib project in fall season 2014, using Randomized Complete Block Design (R.C.B.D.) with three replicates. The results
Have been analyzed according to method 2; model one of Griffing (6). The objective of this study was estimating of general and specific combining ability for parents, their hybrids, respectively, and some genetic parameters for growth, yield and its components characters. Results of statistics analysis showed that there were significant differences among genotypes for all studied characters. Results of genetic analysis showed that Mgca. In addition, Msca. Were highly significant in all studied characters and the σ2gca / σ2sca were less than one for all the studied characters. The effects of GCA were positive and negative among parents for all studied characters , the inbred line syn-1 was found as the best gca effect for ear height 6.122, leaf area 24.885cm2 300-kernel weight 3.499 gm and grain Yield 7.018, While the effect of SCA for single crosses were positive significant for all studied characters. The single cross hybrid (MGW-3×S-165) had highest SCA effect for 300-kernel weight 15.816 gm and the single cross (Syn-22× ZM-9) had highest SCA effect for ear length 2.697cm and for grain yield per plant 51.212 grain. The values of (σ2D) were more than that (σ2A) for all studied characters. The broad sense heritability was high between 85.55% for ear high and 99.39% for 300-kernal weight, while narrow sense heritability was low for all studied characters. The value of average degree of dominance was more than one for all studied characters.

Heterosis and combining ability in several agronomic characters of maize inbred lines

F. Y. Baktash

ANBAR JOURNAL OF AGRICULTURAL SCIENCES, 2009, Volume 7, Issue 1, Pages 178-199

Diallel cross was performed among eight maize inbred lines (1-IPA 2, 2-IPA 7, 3–IPA 21, 4-IPA 12, 5-71-5, 6-IPA 6, 7- IPA 3 and 8-IPA-14) in the field of Field Crops Department, College of Agriculture, University of Baghdad, during spring and fall seasons in 1999 and 2000. The objective was to evaluate several maize inbred lines and their crosses, and estimation gene action in several maize characters. In the first season (spring 1999), inbred lines were propagated, while in the fall season 1999, a set of 28 hybrids were developed. Hybrid yield trails were conducted during spring and fall seasons in 2000, using randomized complete block design with three replications. Significant differences were found among several averages and heterosis of studied characters. The plants of the hybrids (1x7) and (3x7) were earlier in tasseling and silking in spring and fall seasons. The plants of the hybrids (4x7), (1x4) and (7x8) had higher ear height. The hybrids (1x3) and (3x6) were superior in leaf area in both seasons. The higher grain yield (99.33 gm/ plant) produced from crosses (5x8) in spring season, while in the fall season the hybrid (1x3) produced the highest grain yields (181.60gm/ plant). The higher degree of dominance and broad sense heritability were found in the grain yield, while the highest narrow sense heritability produced in the silking. The single cross hybrid (1x3) could be promising in the fall season in central Iraq.