Impaired male meiosis and multiple associations in Chaerophyllum L. from the Western Himalayas, India

Abstract

We present a cytological study of species of the genus Chaerophyllum L. (Apiaceae) by analysing five accessions covering three species from the Western Himalayas, India. The species are collected and studied for detailed male meiosis, multiple associations and pollen fertility. All the studied species exist at diploid level (based on x=11), and show a meiotic chromosome count of 2n=22 at diakinesis and metaphase-I, and regular chromosome distributions at anaphases-I/II. C. Aromaticum is reported for the first time from India and found to be in conformity with the earlier reports of 2n=22 from outside India. Out of three studied species, two (C. Acuminatum and C. Aromaticum) showed the presence of multiple chromosomal associations at metaphase-I of meiosis-I. The paper herein discusses for the first time the occurrence of multiple associations in these species. The course of meiosis in all studied species shows impaired meiotic course in the form of cytomixis, chromatin stickiness, laggards and chromatin bridges. Abnormal microsporogenesis results in heterogeneous-sized pollen grains and reduced pollen fertility.