Abstract
The effects of developmental stage of the anther, ageing of the plant, inbreeding and season on meiotic segregation of an interchange chain quadrivalent were studied in pearl millet, Pennisetum americanum (L.) Leeke. The frequency of adjacent orientation (and segregation) increased with developmental stage of the anther, independent of other factors. Plant age and degree of inbreeding had no demonstrable effects, but there was an indication that high temperature favoured adjacent orientation. Chromosome contraction as measured by change in chromosome length appeared to be negligible during metaphase-anaphase. Therefore, increased adjacent orientation cannot readily be explained by metaphase reorientation resulting from the straightening of chromosomes caused by an increase in their rigidity. It is probable that the unoriented or “mal-oriented” quadrivalents observed regularly at early metaphase I continue to straighten out prior to their delayed orientation. When they finally orientate late in metaphase, their orientation will more likely be adjacent than alternate.
Similar content being viewed by others
References
Akavia N, Ladizinsky G (1978) The effect of temperature on the orientation of the translocation quadrivalent in barley. Chromosoma 67:145–150
Boer P de, Speed RM (1982) Meiosis of T70H translocation trisomie male mice. II. Meiotic rate, spermatocyte interactions and fertility. Chromosoma 87:315–325
Bott CE, Sekhon GS, Lubs HA (1975) Unexpected high frequency of paternal origin of trisomy 21. Am J Hum Genet 27:Abs. 20
Carlson JG (1956) On mitotic movements of chromosomes. Science 124:203–205
Couzin DA, Fox DP (1974) Variation in chiasma frequency during tulip anther development. Chromosoma 46:173–179
Rees H, Naylor B (1960) Developmental variation in chromosome behaviour. Heredity 15:17–27
Rickards GK (1977) Prometaphase I and anaphase I in an interchange heterozygote of Allium triquetrum (Liliaceae). Chromosoma 64:1–23
Sasaki H, Hara Y (1973) Paternal origin of the extra chromosome in Down's syndrome. Lancet 1973 II:1257–1258
Shalev A, Ladizinsky G (1976) The segregation pattern of a Translocation quadrivalent. Chromosoma 57:297–308
Speed RM (1977) The effects of ageing on the meiotic chromosomes of male and female mice. Chromosoma 64:241–254
Sybenga J (1968) Orientation of interchange multiples in Secale cereale. Heredity 23:73–79
Uchida IA (1973) Paternal origin of the extra chromosome in Down's syndrome. Lancet 1973 11:1258
Wagenaar EB (1961a) Cytological studies of the development of metaphase I in hybrids between Triticum timopheevi Zhuk and T. durum. Can J Bot 39:81–108
Wagenaar EB (1961b) Cytological studies of the development of metaphse I in Triticum hybrids. II. The behaviour of univalents in meiotic cell division. Can J Genet Cytol 3:204–225
Zimmerman E (1968) Mechanismus der nondisjunktionalen Chromosomenverteilung and die Ursachen der Pollensterilität bei Rhoeo spathacea. Chromosoma 25:214–248
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Koduru, P.R.K., Rao, M.K., Lakshmi, K.V. et al. Anther development and the orientation of the interchange quadrivalent in pearl millet. Chromosoma 90, 89–93 (1984). https://doi.org/10.1007/BF00292444
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00292444