Abstract
The aim of the present study was to develop a genetic sex marker for the pointed gourd (Trichosanthes dioica Roxb.) to allow gender determination at any stage in the life cycle. Screening of genomic DNA with intersimple sequence repeat (ISSR) primers was used to discover sex-specific touch-down polymerase chain reaction (Td-PCR) amplification products. Using pooled DNA from male and female genotypes and 42 ISSR primers, a putative male specific marker (~550 bp) was identified. DNA marker specific to male is an indication of existence of nonepigenetic factors involved in gender development in pointed gourd. The ISSR technique has proved to be a reliable technique in gender determination of pointed gourd genotypes at the seedling phenophase. The sex marker developed here could also be used as a starting material towards sequence characterization of sex linked genes for better understanding the developmental as well as evolutionary pathways in sexual dimorphism.
Highlights
Dioecism accompanied by sex chromosome dimorphism is common in animals but less prevalent in plants
In a minority of dioecious plants, sex determination depends on sex chromosomes, usually an XY system, in which males are heterogametic (XY) and females are homogametic (XX) [1,2,3]
Male and female DNA pools of twenty accessions of pointed gourd were screened with 42 intersimple sequence repeat (ISSR) primers for sex-specific polymorphisms and reproducibility
Summary
Dioecism accompanied by sex chromosome dimorphism is common in animals but less prevalent in plants. In a minority of dioecious plants, sex determination depends on sex chromosomes, usually an XY system, in which males are heterogametic (XY) and females are homogametic (XX) [1,2,3]. Heteromorphic sex chromosomes have been reported in several families (e.g., Cannabis and Humulus, Cannabinaceae; Silene, Caryophyllaceae; Rumex, Polygonaceae) [2], but our understanding of their evolution and genetics is still relatively poor. The plant strictly maintains the sexual phenotypes of male and female indicating clear genetic difference between both sexes. This clear differentiation of sexual phenotype, combined with its perennial nature, an increasing economic importance of the crop, and recent interest in breeding improved cultivars, makes the species attractive for the study of different aspects of sex determination. A reliable molecular strategy for the early identification of sex in T. dioica has been a priority in breeding programs in order to increase their economic potential and better understanding the developmental as well as evolutionary pathways of dimorphism
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
