Chromosomal Alterations in Mitotic and Meiotic System as Influenced by Gamma Rays <i>in Pisum</i>

Induced chromosomal abnormality and pollen sterility in wild and cultivated urd and mung beans.

“…of meiotic chromosomal abnormalities is broad during diakinesis-metaphase and includes high proportion of univalents, moderate frequencies of multivalents, clumping of chromosomes and non-orientation of metaphase chromosomes. Similar observations have been made in Pisum (Kalloo 1972) and Physalis ( Gupta and Roy 1985). Of the different kinds of meiotic abnor malities, a high proportion of them belongs to univalents.…”

Cytogenetics of Tephrosia II. Mutagenic effect of single, pre- and postirradiation treatments with EMS and MMS in Tephrosia purpurea.

“…The paired fragments observed at anaphase apart from those which were single (chro matid) may have arisen due to breakage of chromosome rather than chromatids (Caldecott and Smith 1952). Paired bridges at anaphase observed in present in vestigation have also been reported by Prasad (1972), Yagyu and Morris (1957), Shaik and Godward (1972), Kalloo (1972), Singh and Godward (1974) and their origin is mainly as a result of fusion between broken chromosomes rather than broken chromatids (Sax 1940, Caldecott andSmith 1952) and the single bridge/bridges result from fusion of two or more broken chromatids (Sax 1940). When the pre sent investigations are taken in conjunction with the one which are not drought resistant (Crotalaria, Phlox, unpublished) one is tempted to conclude that T. pur purea is more resistant to physical and chemical mutagens.…”

Irradiation Studies on the Karyology of Charophyta

“…They reported chromosome and chromatid breakage at different doses ranging from 500 to 10,000 rads and concluded that chromosomal abnormalities rapidly increased with the increase in the dose of gamma radiation. Similar observations were made by Kalloo (1972) with dry seeds of Pisum at high dose of 10, 20 and 40K rads and Shaikh and Godward (1972) in Lathyrus sativus, Vicia sativus and Vicia ervilia at doses of above 5K rads of 60Co gamma-rays. Marshak (1937) in his study with heterogenous materials viz., Lycopersicum esculantum, Mus musculus, Pisum sativum, Allium cepa and Vicia faba, suggested that the frequency of X-ray induced chromosomal abnormalities per cell increased with increase in chromosome size.…”