[Estimation of the efficiency of seed irradiation by thermal neutrons for inducing chromosomal aberrations in M1 of cotton Gossypium hirsutum l].
Exposure of cotton seeds to thermal neutrons at doses of 15, 25, and 35 Gy was shown to induce many altered plants, including sterile and chimeric ones. Most of these phenotypic changes were shown to result from novel genomic, chromosomal, and desynaptic mutations. The presence of these mutations in the karyotype of M, plants often decreased meiotic index and pollen fertility. In translocation forms, the decrease in pollen fertility was caused by the prevalence of quadrivalents in form of rings and chains with adjacent segregation of chromosomes from the translocation complexes. Based on the shapes and sizes of multivalent associations, we performed preliminary localization of translocation breakpoints. A specific feature of the effect of thermal neuron irradiation in M1 was induction of numerous unique chromosomal aberrations, consisting in the appearance in the same plant of several types of mutations (genomic and chromosomal), exchange complexes in the same nucleus, and multiple exchanges involving three nonhomologous chromosomes.
Rakhmatullina
E M
EM
Sanam'ian
M F
MF
D032461:Chromosomes, Plant / Q000235:genetics*; D005298:Fertility / Q000235:genetics / Q000528:radiation effects; D003368:Gossypium / Q000235:genetics*; D009502:Neutrons; D011058:Pollen / Q000235:genetics*; D011839:Radiation, Ionizing; D012639:Seeds / Q000235:genetics*; D014178:Translocation, Genetic / Q000235:genetics / Q000528:radiation effects*