Karyotype analysis and meiotic behaviors of Ducrosia anethifolia: The first case study

Abstract

The medicinal plant Ducrosia anethifolia (DC) Boiss is an annual herb of the Apiaceae family. It originated from Iran and it is used to treat headache and backache in traditional medicine. Mitotic study and meiotic behavior of chromosomes are presented for the first time for D. anethifolia in this study. D. anethifolia possessed n = 11 (2n = 2x = 22) chromosome number forming mainly both rod and ring bivalents with some amount of quadrivalents and univalents. Karyotype analysis according to Stebbins categories, placed chromosomes of this plant in symmetric class of 2A, indicating a symmetric karyotype. The types of chromosomes were metacentric and submetacentric with one pair of satellite chromosomes. A variety of abnormal chromosomal behaviors including chromosomal stickiness, bridge, laggards, micronucleus, mass chromatin and early chromosome migrations were observed, albeit with low frequency. Tetrads with four equal-sized cells were considered normal and any deviation as abnormal. Stain-ability of pollens as an estimation of their fertility was ninety-seven percent. In this study we had few meiotic abnormalities and, as a consequence, a high pollen fertility. Well-filled pollen grains with stained nuclei were regarded as apparently fertile while shriveled, smaller microspores and unstained pollen were counted as sterile. The study reveals that meiosis in this species is normal, with high meiotic index and regular bivalent formation in most studied cells. Key words: Ducrosia anethifolia, karyotype, meiosis, pollen fertility.