Breeding Behavior of an Autotriploid in Hyoscyamus muticus L.

Abstract

Egyptian henbane, Hyoscyamus muticus L. (Solanaceae) is an important source of pharmaceutically valuable compounds, the tropane group of alkaloids (Grieve 1977, Mittal and Saxena 1977, Tyagi et al. 1984). The major alkaloid, hyoscyamine, is used as a sedative, anticholinergic and antispasmodic, and to control gripping pain in intestinal disorders. A cataplasm of its fresh leaves is used as a pain killer and dried leaves are smoked as cigarettes against asthma (Boulous 1983). H. muticus was introduced in India from Egypt during 1977 (Husain et al. 1979) and currently it is under commercial cultivation in tropical and subtropical regions of the country. Gene mapping in H. muticus (2n=2x=28) has never been attempted. Although it is generally recognized that primary trisomics (2n+l) in diploid plants provide an effective means of associating linkage groups and genes with their respective chromosomes and of establishing the independence of linkage groups (Burnham 1962, Khush 1973, Tsuchiya 1983, Khush et al. 1984), they have not been reported, so far, in this plant species. Therefore, in order to conduct systematic cytogenetic analysis in H. muticus, autotetraploids were induced in an elite inbred CIMAP/NP-41 developed at this Institute (Tyagi 1986) and subsequently used to establish autotriploids (Tyagi and Dubey 1989b). These autotriploids are being utilized in a conventional manner to produce primary trisomics and other types of aneuploids. The purpose of the present study was to determine the breeding behavior of an autotriploid by studying the meiotic chromosome constitution of the progeny resulted from its selfpollination, as well as those derived from crosses between the autotriploid and its diploid parent. © 1990, Japan Mendel Society, International Society of Cytology. All rights reserved.