Development and Fertility Restoration of CMS Eggplant Lines Carrying the Cytoplasm of Solanum violaceum

Abstract

A functional cytoplasmic male sterile (CMS) eggplant line carrying the cytoplasm of Solanum violaceum was developed in the past, but the fertility restoring genes (Rf-genes) were not identified. This work aimed to produce the CMS lines of three Hellenic eggplant cultivars (viz., 'Langada', 'Emi' and 'Tsakoniki') using the cytoplasm of S. violaceum and study the inheritance of the Rf-genes. The respective CMS eggplant lines were developed by the backcross method and examined for their fertility parameters. The results demonstrated that female fertility was not affected by the cytoplasm of S. violaceum. In contrast, the occurrence of three male fertility phenotypes (male sterile, male fertile and potentially male fertile) indicated that male fertility was affected by nuclear/cytoplasmic interactions. Male sterile plants were characterized by indehiscent anthers, low pollen viability and abnormal anther morphology. Male fertile plants formed dehiscent anthers with high pollen viability and normal morphology. Potentially male fertile plants initially formed dehiscent anthers, but in later stages formed exclusively indehiscent anthers. Male fertile plants were obtained in the advanced backcross populations of CMS 'Tsakoniki', but not in CMS 'Langada' and CMS 'Emi'. The genetic analysis of fertility restoration indicated that male fertility in the genetic background of cv. 'Tsakoniki' is controlled by one essential genetic locus, affected by a secondary modifying locus. Molecular analysis of cp-DNA and mt-DNA in the CMS lines indicated maternal inheritance of the cytoplasm organelles. Our findings demonstrate that the genotype of the eggplant parent can affect the expression of CMS as well as fertility restoration.

Heterosis Breeding in Eggplant (Solanum melongena L.): Gains and Provocations

“…Yoshimi et al [102] reported the variation in the flanking DNA sequences of five mitochondrial ATP and COX genes as the causal genes for each CMS type variation in the eggplant. Recent findings suggested that eggplant parent genotype can influence both the CMS expression and fertility restoration [10]. With the advancement in genomics and transcriptomics studies, the effort has been made ease in identifying molecular marker linked to the Rf-genes which promote the integration of Rf-genes in various eggplant genetic backgrounds.…”

“…Hybrids and improved agronomic techniques have resulted in a steady linear increase in the performance of vegetable crops [7,8]. In the case of eggplant, first-time Kakizaki [9] found the potential use of hybrids as commercially, citing the higher yields of hybrids compared to a standard for the years 1923-1926 [10]. Further, the authors also determined that the level of heterosis is directly proportional to the diversity among the parents, which brought together several favorable diverse alleles of several genes.…”

Molecular basis of heterosis and related breeding strategies reveal its importance in vegetable breeding

“…To produce hybrid tomato seeds, pollen-abortive type and functionally sterile lines are often used 109 – 111 . Cytoplasmic male sterility occurs in eggplant 112 , 113 and pepper 114 , 115 . Gynoecious lines tend to exist in Cucurbitaceae 116 .…”

The use of genetic, manual and chemical methods to control pollination in vegetable hybrid seed production: a review

“…A recessive gene conferring functional male sterilityfms - (Phatak et al 1991) was tested, but the occasional presence of pollen in the indehiscent anthers due to environmental factors inhibited its application to hybrid seed production (Daunay 2008). Well-characterized genetic resources related to CMS systems and molecular tools designed to assist selection will provide new possibilities for eggplant hybrid breeding in the future (Mizanur et al 2016, Krommydas et al 2016.…”