Karyological and Electrophoretic Distinction between Sexes of <i>Trichosanthes bracteata</i>

Abstract

Chromosome studies and soluble protein profiles, fractionated by reducing and non-reducing SDS-PAGE, were carried out in dioecious Trichosanthes bracteata. Somatic chromosome no. 2n = 22 was recorded in both sexes. The karyotype of male and female plant shows high homogeneity and the absence of any heteromorphic pair of chromosomes negates the possibility of XY mechanism. Soluble protein profiles from the tuberous roots of the male and female plants, fractionated by reducing SDS-PAGE, did not show any qualitative distinction. Whereas the protein profile in non-reducing SDS-PAGE reveals a clear distinction when compared on a single gel. The difference is marked by the presence of a disulphide linked tertiary or folded protein at 19 k D region detected in male sex. However, at the level of primary structure the qualitative expression is similar indicating a common ancestry.

FISH Karyotype Analysis of Four Wild Cucurbitaceae Species Using 5S and 45S rDNA Probes and the Emergence of New Polyploids in Trichosanthes kirilowii Maxim.

“…A hexaploid species has been reported in Trichosanthes bracteata (Karmakar et al, 2013) and diploid and octaploid cytotypes have been reported in T. kirilowii species (Qian et al, 2012). However, the hexaploid and decaploid cytotypes in T. kirilowii found here were not previously reported.…”

Sex-oriented research on dioecious crops of Indian subcontinent: an updated review

“…A noticeable proportion for female plants over males (2.4:1) was observed by Kumar et al (2008) by in vitro culture of almost fully developed embryos; the probable cause might be due to the action of lethal/sub-lethal gene(s) linkage with the female sex confirming locus. Hazra et al (2011) reported a pair of physiologically distinct chromosomes carrying the sex determining genes in pointed gourd, whereas later on, Karmakar et al (2013) karyotyped another dioecious Trichosanthes (T. bracteata) revealing the absence of XY mechanism.…”

Transcriptome sequencing and screening of genes related to sex determination of Trichosanthes kirilowii Maxim

“…Therefore, Yu et al and Li used PAGE to identify the early sex of TK and found certain differences between male and female strains in enzyme concentration and spectral bands [1,2]. Karmakar et al used total proteins of TK roots to identify plant sex and found a slightly sex differential band with a molecular weight of 19 KDa [3]. Qu et al's study of RAPD-SCAR had found that S 1200 primers can generate a 600-bp amplification band specifically in male TK [4].…”