Reciprocal translocations in grass pea (Lathyrus sativus L.): pattern of transmission, detection of multiple interchanges and their independence.
Grass pea (Lathyrus sativus L.) is a diploid crop having 2n = 14 chromosomes. Four different plant types, heterozygous for reciprocal translocation (RT), RT-1, RT-2, RT-3, and RT-4 showing pollen semisterility, were isolated in induced mutant population of three varieties of grass pea. Transmission rate of these 4 translocations was studied in advanced selfed and intercrossed progenies, whereas multiple chromosomal interchanges were detected by the pattern of chromosomal ring formation at meiosis I in the F(1) progeny of RTxRT. RT transmitted at an average of 48.89% in selfed progeny and along with normal plants, RT and translocation homozygotes produced some trisomic plants in the segregation progeny. RT-3 showing maximum frequency (68.20%) of zig-zag or alternate chromosome orientation exhibited highest transmission (55.20%). Presence of a ring of 6 or 2 rings of 4 chromosomes in F(1) double heterozygotes obtained from RTxRT suggested involvement of one common chromosome in translocations of RT-1, RT-2, and RT-4 but a different one in common between RT-2 and RT-3. No common chromosome, however, was shared by RT-3 and RT-4. Thus, 5 out of 7 chromosomes are involved in the present RTs, and one of the translocated chromosomes in RT-1 line was always associated with nucleolar organizing region.
Talukdar
Dibyendu
D
Department of Botany, University of Kalyani, Kalyani, West Bengal, India. dibyendutalukdar9@gmail.com
D020090:Chromosome Segregation / Q000502:physiology; D032461:Chromosomes, Plant / Q000235:genetics; D003433:Crosses, Genetic; D005828:Genetics, Population; D006720:Homozygote; D040582:Inheritance Patterns / Q000502:physiology*; D027807:Lathyrus / Q000235:genetics*; D008540:Meiosis / Q000235:genetics; D012854:Sister Chromatid Exchange / Q000235:genetics / Q000502:physiology; D014178:Translocation, Genetic / Q000235:genetics*; D014314:Trisomy / Q000235:genetics