Induced Reciprocal Translocation in <i>Pisum sativum</i> L.

Abstract

Five translocation heterozygotes were induced by using gamma rays in Pisum sativum. The induced translocations showed a ring or chain of 4 chromosomes and 5 bivalents in most of the PMCs at diakinesis/metaphase I. Translocation heterozygotes predominantly showed an adjacent type of orientation as compared to alternate orientations of the centromeres which is reflected in the pollen stainability and pollen fertility of the plants. The translocation heterozygotes established could be used for gene mapping and the production of trisomics. They would have altered karyo-types useful for other experimental studies on Pisum sativum. Pisum sativum L. (2n=14) commonly known as pea, of the family Fabaceae is an important le-gume grown and consumed extensively worldwide. As a rich source of protein, carbohydrates, and vitamins, pea is important in human nutrition. Consumed mostly as green peas, total production worldwide is around 8.3 million tons (FAO 2008). Pea is the fourth leading legume in terms of world consumption and the second most important legume after the common bean (Phaseouls vul-garis L.) in India with a total annual production of 3,029.40 tons (NHB 2010). Identification of agriculture via mass use of chemical fertilizers has dramatically reduced natural soil fertility potential, while legumes have a unique ability to assimilate atmospheric nitrogen in symbiosis with soil bacteria. In addition, pea is one of the best models to study triple symbiosis (legumes-arbuscular mico-rhizal fungi-nodule bacteria). Mutations are heritable changes in all living organisms, whether occurring spontaneously or induced artificially. Spontaneous mutations occur in nature in all organisms without mans interference. In induced mutations, however, man interferes with plants and animals by artificially inducing in them mutations by various mutagens like chemical mutagens and irradiations. Studies on the effects of ionizing radiations and their utility in inducing chromosome mutations have been a topic of immense interest for cytologists. Mutation techniques have proven useful in obtaining novel traits and creating genetic variability. Gamma irradiation as a mutagen can induce useful as well as harmful mutations in plants. In the present study, for the genetic improvement of pea, induced mutations through gamma rays were attempted and 5 translocation heterozygotes have been isolated as a result. Translocation heterozy-gotes are characterized by the occurrence of new morphological chromosomal units out of segments of non-homologous chromosomes. Recently, Sybenga et al. (2012) have found that trisomy greatly enhances interstitial crossing-over in a translocation heterozygote of Secale. The aim of the present study was to induce translocation and if possible produce a genetic map of the P. sativum, as has been done for Vicia faba (Rieger and Michaelis 1962, Schubert et al. 1982, 1991). Karyotype reconstruction either natural or induced is of great importance to plant breeders and geneticists (Schubert et al. 1991). Here, we present a...

Effect of colchicine on meiosis of <i>Chrysanthemum carinatum</i> Schousb. (Asteraceae)

“…Radiation treatment induces plant damage, by producing chromosomal aberration and other abnormalities, in reduction in chromosome number and other abnormalities as reported in Chrysanthemum (Dowrick and El-Bayoumi 1966). Furthermore, reduction in chromosome number and induced reciprocal translocation reported in Pisum sativum (Verma and Goyal 2012).…”

Cytological Characterization of Induced Multiple Translocation Heterozygote in Pearl Millet (<i>Pennisetum glaucum</i> L.)

“…In the present study, a multiple interchange heterozygote in pearl millet (Pennisetum glaucum L.) was isolated from gamma ray treated seed progeny. In this laboratory, a number of translocation lines have been isolated with the help of gamma irradiations in various crop plants such as Vicia faba (Verma and Rao 1994), Pisum sativum (Verma and Goyal 2012) and Safflower (Verma and Shrivastava 2014). The present study describes the cytological behaviour of induced multiple translocation heterozygote and analyses the probable causes for peculiar observations.…”

Radiation-Induced Reciprocal Translocations in Safflower (Carthamus tinctorius L.)

“…Perhaps one of the metacentric chromosome pair and one of the other metacentric or submetacentric pair were included in the reciprocal exchange of chromosomes. The presence of metacentric chromosomes in reciprocal translocation was evident from the bigger size of the interchange complex (Verma and Goyal 2012). The chromosome orientation of quadrivalents in translocation heterozygotes at metaphase I is critical.…”