RECIPROCAL EFFECT ON EAR TIP FILLING AND DIVERSITY OF AGRONOMIC TRAITS IN F1 AND F1R MAIZE GENOTYPES BASED ON MULTIVARIATE ANALYSIS

Abstract

The performance of maize in reciprocal crosses can be altered because the female parent supplies maternal tissues, cytoplasmic inheritance and the physiological environment for kernel development. The objective of this study was to examine agronomic variation and the association of crossing direction and ear-tip filling in direct (F1) and reciprocal (F1R) maize hybrids. The study was carried out in Randuaguang Village, Lumajang, East Java, Indonesia in March to June 2025. Twenty genotypes of 10 pairs of F1 - F1R were evaluated using randomized complete block design with three replications. Eleven agronomic traits were standardized and subjected to principal component analysis (PCA) and Ward’s hierarchical clustering based on Euclidean distances. The first four principal components accounted for 72.4 % of the total variation, with PC1, PC2, PC3 and PC4 accounting for 27.8 %, 21.3 %, 12.2 % and 11.1 %, respectively. Cluster analysis separated the genotypes into four groups. Cluster 3 contained six F1R genotypes and one F1 genotype and had the longest mean unfilled ear-tip section (1.72 cm), whereas Cluster 2 comprised five F1 and three F1R genotypes and had a shorter mean value (0.52 cm). F1-G8 formed a single-genotype cluster and combined the highest ear weight (288.0 g) and kernel weight (138.0 g) with the shortest unfilled ear-tip length (0.17 cm). The results indicate that crossing direction was associated with multivariate agronomic variation, although the response differed among parental combinations. F1-G8 is therefore a promising candidate for further evaluation, while direct statistical comparisons and multi-environment testing are required to confirm reciprocal effects and performance stability.