Analysis of Morphological Variation, Grouping and Path Coefficient Studies in a Set of Maize Inbred Lines Local to North East Hill Region of India

Abstract

In the current study a total of 191 maize inbred lines were set up in an augmented randomized complete block design to study the genetic variation and interrelationship of different yield contributing parameters. Observations were recorded on a total of nine phenological and ear / kernel related traits. Significant results for ANOVA indicated presence of substantial variation while the first three axes of PCA could explain 75.54% of the variation present. Ear and flowering traits were orthogonal to each other and the highest variation in PC1 could be attributed to total grain weight. This was also reflected in the Agglomerative Hierarchical Clustering which grouped the inbreds into five clusters primarily on the basis of total grain weight which accounted for the highest variation between the clusters. Substantial heritability genetic advance as percentage of mean were observed for total grain weight indicating that selection for grain weight would be fruitful. Association and path coefficient studies after adjustments for multi-collinearity using k constant method (0.05) revealed that total grain weight was highly and positively correlated with ear weight, number of grain kernel rows and seed index. Therefore, simultaneous selection for these traits would be useful. Overall, our studies go on to show presence of sufficient genetic variability in the inbreds under study and hybridization between inbred lines grouped in different clusters have a high chance of producing heterotic hybrids.

Correlation and Path Analysis in Elite Maize (Zea mays L.) Lines

“…Path coefficient analysis revealed that days to tasseling (0.0108), ear diameter (0.0057), number of kernels per row (0.0058), 100-seed weight (0.0122), shelling percentage (0.1439), cob yield per plant (1.0014), germination 1 st count (0.0094), seed vigour index-1 (0.0131), seed vigour index-2 (0.0125) and speed of germination (0.0060), had a positive direct effect on grain yield per plant, implying that selecting for these characteristics would likely to result in an overall improvement in grain yield per plant. Similar findings were reported by [4], [12], [14] and [19] for days to 50% tasseling, ear diameter, number of kernels per row, cob yield per plant, [20] for 100 seed weight, [15] for Shelling percentage, [18] for seed vigour traits in soyabean. As a result, it is advised that these characteristics should be prioritized in the yield improvement programme.…”

Genetic Variability and Interrelationship in Maize (Zea mays L.) Genotypes for Grain Yield and Yield Component Characters

“…High significant positive correlation with yield per plant was recorded by number of cobs per plant followed by ear length, number of grains per row, 100 grain weight, harvest index, biological yield, suggesting that indirect selection for high yield through direct selection for these characters will be highly effective (Table 3). Similar type of results for number of grains per row [18][19][20], number of cobs per plant [21], ear length [22,23], 100 grain weight [24,25], harvest index [26]. Flowering traits like days to 50% tasseling and days to 50% silking showed significant negative correlation with grain yield.…”

Combining Ability and Heterosis of QPM Hybrids for Yield, Qualitative and Quantitative Traits under Heat stress in Different Environments

“…In view of the general combining ability results different parental lines under HS condition, no parental line showed great combiners for every one of the characteristics thus, parental line P 7 showed great general combining ability for each and every characters with the exception of seed index and starch content [23][24][25][26][27].…”