Chromosomal studies in four seed spices of Umbelliferae

Abstract

Seed spices of Umbelliferae namely, Apium graveolens L. (celery), Cuminum cyminum L. (cumin), Foeniculum vulgare Mill. (fennel) and Trachyospermum amni L. (ajowan) are economically important as they are consumed and exported from India as raw materials as well as value added products. The present investigations were carried out to gather information on the status of karyotype and chromosome behaviour in the above mentioned four seed spice species. For karyotype analysis, seeds of celery, cumin, fennel and ajowan (Nadia local cultivars obtained from Zonal Adaptive Govt. Research Station, Krishnanagar, West Bengal) were presoaked in distilled water for 12h and allowed to germinate (18°C ± 1°C) in petriplates lined with moist filter papers. Healthy roots of proper size (2-3mm) from the seed spices were collected (12 pm to 12.30 pm) and pretreated with supersaturated aqueous solution of para-dichlorobenzene containing tinge of aesculin (initially at 0-4oC for 10 min and finally at 16°C ± 1°C for 3-4 h), fixed in 1: 3 propiono-alcohol (vlv) for overnight and stained in 2% orcein-1(N) HC1 mixture (9:1) for 2-3 h. Root tips were squashed in 45% acetic acid and observed under the microscope.