Showing papers by "Central Tuber Crops Research Institute published in 1966"

Occurrence of multiploid sporocytes in the genusSorghum

Abstract: The breakdown of the meiotic cycle in the plasmodial microsporocytes is described in detail for the interspecific hybrid,S. almum (2n=40)×S. halepense (2n=40). The plasmodial masses probably result from a suppression of wall formation during premeiotic mitosis. The possible role played by some of the mitotic organelles in the formation of atypical as well as multipolar spindles in the plasmodial cells is also considered.

Cytomorphological Studies on Some Interspecific Hybrids in Eu-Sorghums

Abstract: Pachytene analyses in interspecific hybrids have proved to be an important tool in recent cytotaxonomic investigations in several taxa. Unfortunately, such studies in the genus Sorghum have largely been confined to diakinesis and later stages. Thus the conclusion that interspecific hybrids in Eu-Sorghums are not qualitatively or quantitatively different from those in the corresponding parents, arrived at by some workers (see Celarier 1959) on the basis of their observations of normal bivalent formation at diakinesis and MI appears to be an over-simplification of the problem in the light of the results obtained in the present study and those reported by Magoon and his co-workers (see Magoon 1964 a and b). In this study, several species of Sorghum, both cultivated as well as wild, were crossed in different combinations so that the knowledge thus gained regarding the nature of internal isolating mechanisms that may be operating could be utilized in better understanding of the ancestral relationships among the parents. A detailed account of the cytomorphological behaviour of various interspecific hybrids, not subjected to such an analysis before is presented below.