Effect of high temperature on meiosis in Lolium: Nucleolar inactivation

Monosomes and their Influence on Meiosis in ‘Holdfast’ (<i>Triticum aestivum</i> L.)

“…Recent researches on plant chromosomes also indicate that the heterochromatic regions contain histone-type proteins in addition to those found in the euchro matic regions, and that these add to the complexity of behaviour and function associated with such regions. Jain (1957Jain ( , 1958 Table 2 data are given on the formation of univalents, multivalents, and fragments in the different monosomics, and contrary to the observations of Morrison (1953) on 'Chinese Spring', all these lines in 'Holdfast' are not necessarily the same in their behavior. They fall into the following groups .…”

Effects of external environmental factors on chromosome pairing in autotetraploid rye.

“…Many studies have confirmed the deleterious effects of high temperature treat ments on chromosome pairing behaviour (Darlington 1940, Elliot 1955, Dorwick 1957, Jain 1957, Wilson, 1959 changes were mainly due to treatment effects .…”

Variability in Length and Arm Ratio of the Pachytene Chromosomes of Corn

“…It would also give each short arm a greater inherent variability than the long arm to which it is attached if the length unrelated variability is the same for both arms of a chromosome (or greater for the short arm or even somewhat greater for the long arm). The cases of differential chromosome contraction reported by Jain (1957) and Rees (1958) are also suggestive of a kind of variability characteristic for individual chromosomes.…”

“…Genetic and gross environmental differences are expected to operate at source and plant level. Temperature effects on chromosome con traction have been described by Matsuura (1935Matsuura ( , 1937, Straub (1937), Huskins and Wilson (1938), Wilson and Huskin (1939), Barber (1940), Darlington and LaCour (1940), Swanson (1942Swanson ( , 1943, Wilson and Boothroyd (1944), Jain (1957) and Rees (1958). Genotypic control of chromosome length has also been known for many years (Lesley and Frost 1927, Lamm 1936, Upcott 1937, Swanson 1942, 1943, Burnham 1946).…”