Primary Simple Trisomics in Pearl Millet

Abstract

To establish a series of trisomics in Pennisetum typhoides (2n = 14), plants with 2n + 1 chromosome numbers were isolated from the progenies of triploid plants and triploid-diploid crosses. These primary simple trisomic plants were distinguishable from the diploids by their relatively poor vigour, short height, narrow leaves and late flowering. They were also distinguishable from one another and were classified into seven morphological groups: 'Tiny', 'Dark Green', 'Lax', 'Slender', 'Spindle', 'Broad' and 'Pseudonormal'. The extra chromosome in the seven trisomic types could be distinguished on the basis of somatic chromosome morphology.

Cytological Behaviour of Primary Simple Trisomics of Pearl Millet

“…S. and H. (2n=14) has been identified by GILL et al ( 1970 ). The trisomies provide a very useful tool for detecting linkages among genetic characters.…”

Cytomorphological behaviour of primary trisomics in pearl millet (Pennisetum americanum (L.) Leeke).

“…Each of the seven possible trisomics with specific diagnostic characteristics have been described by Gill et al (1970b) and Nameeta (1973), which are consistent regardless of the varietal source. Though different genetic backgrounds may effect the expression of the extra chromosome to a certain extent, the main morphological traits remained similar.…”

“…Trisomics morphologically distinguishable from diploids have been reported in Datura (Blakeslee 1922), tomato (Rick and Barton 1954), barely (Tsuchiya 1967), sorghum (Schertz 1966), rice (Hu 1968), pearl millet (Gill et al 1970b, Nameeta 1973. However, the trisomics were indistinguishable from the diploid sibs in Hyacinthus (Darlington et al 1951), maize (Rhoades 1955).…”

Primary Trisomics ofTrigonella Corniculata. I. Morphology and Identification

“…Though primary trisomies have been reported m a large number of crop plants, a complete series exists only in a limited number of species, viz., Datura (BLAKESLEE and BELLING 1924), maize (McCLINTOCK 1929), tobacco (GooDSPEED and AvERY 1939), wheat (SEARS 1939), tomato (RICK and BARTON 1954), Antirrhinum ma;us (SAMPSON et al 1961), Dactylus glomerata (THOMAS 1967), Lotus pedunculatus (CHEN and GRANT 1968), rice (Hu 1968), pearl millet (GILL et al 1970), jute (DAs and lYER 1972) arid Sorghum (ScHERTZ 197 3 ). This paper reports a complete series of primary trisomies in Trigonella corniculata L. (2n = 16).…”