Stability of Cytoplasmic Genetic Male Sterility and Fertility Restoration in Pigeonpea

Abstract

In cytoplasmic genetic male sterility-based (CGMS) hybrid seed production, instability of expression of male-sterility and fertility restoration across a wide range of environments are two of the major difficulties. Therefore, the present study was carried out to investigate the stability of male sterility of nine CGMS lines under three dates of sowing and the fertility restoration of 10 CGMS-based pigeonpea (Cajanus cajan (L.) Millsp.) hybrids at three different locations. Significant variability existed for pollen fertility among hybrids and sterility among cytoplasmic male sterile (CMS) lines. All the hybrids except ICPH 3494 and ICPH 3491 exhibited high (>80%) pollen fertility across locations. Hybrids ICPH 2671, ICPH 2740, and ICPH 3933 had 100% male-fertile plants across locations. All the CMS lines had completely male-sterile plants across sowing dates. The CMS lines BRG1 A, Hy3C A, BRG3 A, and TTB7 A exhibited 100% pollen sterility at different sowing dates. The pooled analysis revealed a significant genotype × environment interaction for pollen fertility and sterility. The genotypic main effect + GE (GGE) biplot of hybrids showed that hybrids ICPH 2671, 2740, 3933, and 3461 were stable for fertility restoration. With the exception of ICPA 2047 and ICPA 2051, all the CMS lines were highly stable with high mean performance and least distance from AEA (average environmental axis). Male-sterility in A4 cytoplasm was independent of environmental conditions. Different dates of sowing did not affect expression of male sterility of these CMS lines.