Evaluation of the Combining Ability in Mulberry (Morus spp.)
Ramya Harika K.
Department of Sericulture, FC&RI, TNAU, Mettupalayam – 641 301, India.
P. Mangammal *
Horticultural College and Research Institute, Tamil Nadu Agricultural University, Paiyur, Tamil Nadu, India.
P S Devanand
Department of Forest Biology and Tree Improvement, Forest College & Research Institute, Tamil Nadu Agricultural University, Mettupalayam, Tamil Nadu, India.
P. Tejasree
Department of Genetics and Plant Breeding, SV Agricultural College, Tirupati-517502 Andhra Pradesh, India.
Ishita Garai
Department of Sericulture, University of Agricultural Sciences, Bangalore, Karnataka, India. f ICAR -Krishi Vigyana Kendra, Salem, Tamil Nadu, India.
Karthick Mani Bharathi B
Department of Sericulture, FC&RI, TNAU, Mettupalayam – 641 301, India.
M. Kiruba
ICAR -Krishi Vigyana Kendra, Salem, Tamil Nadu, India.
P. Kumar
Horticultural College and Research Institute, Tamil Nadu Agricultural University, Paiyur, Tamil Nadu, India.
*Author to whom correspondence should be addressed.
Abstract
The research aimed to comprehend the patterns of gene action influencing the inheritance and expression of quantitative features in mulberry by studying combing ability. Four parents viz., V1, G4, MR2 and S36 were used in mating design. Estimates of SCA depicted that crosses V1 × G4 (shoot diameter and chlorophyll - b) and it’s reciprocal cross G4 × V1 (chlorophyll – a, total chlorophyll) showed high significant SCA effects. V1 × MR2 for shoot diameter and lowest positive SCA for internodal distance. Overall, the crosses with the highest SCA values for specific traits consistently involved V1 as one of the parents. This observation highlights that V1, which possesses the best general combining ability (GCA) effect, contributes significantly to the high SCA observed in these crosses for the traits studied. V1 and MR2 were the best general combiners, with high GCA for growth traits. Crosses G4×V1 and V1×G4 demonstrated positive SCA effects for most traits followed by S36 × V1 and MR2 × V1. Notably, SCA variance was greater than GCA variance for most traits, indicating the dominance of non-additive gene effects.
Keywords: General combining ability, specific combining ability, Variance ratio and Non – additive gene action