First Report on Aneusomaty and Chromosomal Chimeras in Male Track of Luffa cylindrica (L.) M. Roem

Abstract

Morpho-cytological studies on existing germplasm of agronomically important taxa provide valuable data for identifying more productive, cytologically normal and stable lines. Presently, one commercial and two local cultivars, viz. MBLC1, MBLC2 and MBLC3 of Luffa cylindrica, were studied for morphological aspects. Of these, two (MBLC1 and MBLC2) bearing larger fruits were more productive. For determining cytological status of these cultivars, chromosome count was made from dividing somatic cells. While MBLC2 and MBLC3 had all the cells with normal diploid count (2n = 26), MBLC1 had deviant counts (23–25 chromosomes) in 8–47% cells in five of the seven root tips scanned, with the cells of the remaining two tips having 26 chromosomes. For determining whether germ line cells also exhibit numerical and structural chromosomal aberrations, meiocytes of three cultivars were scrutinized for chromosome count and behavior. These cultivars usually had 7–11% pollen mother cells (PMCs) with variable number of chromosomes (16–28). Besides, 4–6% meiocytes of MBLC1 and MBLC2 were further notable in having quadri- and hexavalents. These anomalies accounted for irregular anaphasic segregations in 8.3%, 9% and 10.5% cells of MBLC1, MBLC2 and MBLC3, with percentage pollen stainabilities of these being 89, 90 and 94, respectively. Seed set per fruit in the present cultivars, however, valued less (140, 161 and 152) than that on record for normal diploids. In view of current detection of aneusomaty, chromosomal chimerism in male track and reduced seed set in present cultivars, it is proposed that the cultivars commonly grown by farmers should be cytologically evaluated and only those with high yield, normal diploid count, regular chromosome behavior and good seed set should be recommended for cultivation.