Chromosome squashes in Cereals

Abstract

Root tips were soaked 1-2 hours at 18-20" C. in a freshly prepared saturated aqueous solution of a-bromonaphthalene, 1-2 hours in water, and fixed in a mixture consisting of 1% chromic acid, 5 ml.; 2% osmic acid, 1 ml.; and 0.002 M 8-0xyquinoline, 1 ml. for 0.5-1.0 hour at 10-14" C. They were then successively treated as follows: water 1-2 minutes; 1% H,SO,, 10-15 minutes; water, 1-2 minutes; 1% Cr03, 0.5-1.0 hour; water 3-5 minutes; 1 N HCl, 45 minutes at 60" C.; water 3-5 minutes; leucobasic fuchsin (de Tomasi) 0.5-1.0 hour. The brightly stained tips of the roots were cut off and squashed in the usual manner in a drop of aceto-carmine under a cover glass. The cover glass was sealed with paraffin and the slide stored overnight. T h e paraffin was removed and the cover glass separated in a -l : l mixture of acetic acid and n-butyl alcohol. Final processing consisted of passing the slide through pure n-butyl alcohol; a 1:l mixture of redistilled turpentine and n-butyl alcohol (to remove-the osmic acid stain); n-butyl alcohol, 2 changes, and covering in balsam.

Gamma radiation induced cytological abnormalities in Lycopersicon esculentum Mill. var. pusa ruby.

“…Meiosis was studied in squashes of pollen mother cells fixed in Carnoy's fluid and made permanent with butyl alcohol (see Swaminathan et al 1954, Bhaduri andGhose 1954). Pollen fertility was estimated by using Alexander's stain (1969).…”

Meiotic studies in species-hybrids of the Solanum nigrum L. complex.

“…Meiosis was studied from propiono carmine squashes of pollen mother cells (Swaminathan et al 1954). The slides were made permanent with butyl alcohol (Bhaduri and Ghosh 1954). Estimation of pollen fertility was carried out on pollen grains stained in propionocarmine.…”

Morphological diversification and genetic lsolating mechanism between some members of Solanum nigrum complex.

“…Meiosis was studied from propionocarmine squashes of pollen mother cells (Swaminathan et al 1954), and slides were made permanent by butyl alcohol schedule (Bhaduri and Ghosh 1954). Pollen fertility was determined on the basis of stainability in acetocarmine.…”