Research article

Chromosomes Behaviour In Three Species Of Capsicum Genus

Abstract

The genus Capsicum consists of 35 species out of which five are widely domesticated and cultivated in the tropical and subtropical regions of the world. The research was undertaken at the Faculty of Life Sciences, Department of Plant Science, Modibbo Adama University, Yola. Anthers pollen were collected by crushing with tweezers to release pollen grains. Harvesting of the pollen was done between hours of 9:30 am and 10:00 am. The excised anthers were immersed in 0.02%Colchicine for 4 hours. The pre-fixed flower buds were fixed directly into Carnoy’s Fluid (“Glacial acetic acid and absolute ethanol” in a 3:1 ratio) solution for 24 hours. The anthers were then washed in distilled water at room temperature, transferred into 1N hydrochloric acid (HC l) at 60º C in a water bath for 5-8 minutes. The Hydrolyzed flower buds were rinsed in water and one anthers at a time was squashed in aceto-orcein stain. Photomicro graphs of suitable cells were taken for illustration. The result revealed that all the three species revealed a diploid chromosome count of n = 12 = 24. Also, the result showed that diplonema, zygotene, leptotene, pachytene and diakinesis at Prophase I. Non-oriented chromosomes at Metaphase II were observed. One lagging chromosomes as well as chromatid separation and Diakinesi and scattered chromosomes at Anaphase I were observed in all the three species. Pollen viability in C. annuum L, C. chinenses Jacqs. C. frutescens L. were 71.3 %, 68.4%and 84.2%viable, respectively. The pollen viability was scored according to staining level (pollen with bold red color as viable and colorless as nonviable. Consequently, viable and non-viable pollen grains of variable sizes were ascertained. This study helped in unravelling the different evolutionary trends in the genus.