Resynthesizing the Crop Progenitors to Capture Variability Lost During Crop Evolution and Domestication

 

 

Evolution of crop plants is continuously occurring in nature and due to interaction of human food activities made it possible to exploit the advantages for food, clothes and shelter. During the course culture development and utilizing crop plants in breeding programme, genetic base as decreased gradually. This narrow genetic base needs to be broaden for further improvement in many of the diploid and polyploids crops like Wheat, Brassica, Groundnut, Potato, Cotton etc. Resynthesizing the crop is one of the most important activity helps in generating new germplasm resources can be utilized in present breeding activity.

Cytogenetics has given a great contribution to wheat studies and breeding, due to viability of chromosomal variations because of homology among genomes in this allohexaploid species and the genus Triticum. Fertile amphidiploids were recovered only from crosses among entries of tetraploid T. durum and diploid Ag. Squaroso they originated 11 fertile synthetic amphidiploid lines from seven different combination. Useful stem and leaf rust as powdery mildew resistance for fertile use in breeding programme.

Resynthesizing of genome was done using triploid solanum spp. x solanum juzepczkii and pentapliod solanum spp.x solanum curtilobum crosses. Pentapliod solanum spp.x solanum curtilobum has not been successful but tetapiod plants were obtained on the pressure. The newly developed tetapiod contains at least one genome from solanum acule and hybridize easily with spp. andigenes. This helps in transefer of genes into cultured gene pool from frost resistance of solanum acule.

Brassica resynthesizing was done to obtain variability for oil and meal quality, using Brassica carinata (bbcc,2n=34) from its related digenic species viz, Brassica napus (AACC,2n=38) and Brassica juncea (AABB,2n=36). An alternate procedure for resynthesis Brassica juncea developed by chromosome doubling using colchicines treatment such derived resynthesized amphidiploids were superior to those developed using conventional resynhesis. Generating new germplasm and creating variability using wild relatives resynthesizing is the way for plant breeder.

Key words: Resynthesis, evolution, domestication. crop progenitor.

References:

1. Banga, S.S. and Kaur, N., 2009, An alternate procedure for resynthesis of Brassica juncea. 16th Australian Research Assembly on Brassicas., 1:1-5.

2. Fernandes, M. I. and Prestes, A. M., 2000, Transfer of disease resistance from related species by artificial resynthesis of hexaploid wheat (Triticum aestivum L.). Genetics and Molecular Biology., 23(4): 1051-1062.

3. Schmiediche, P. E., Hawkes, J.G. and Ochoa, C. C., 1982, The resynthesis of S. juzepczukii and S. curtilobum. Euphytica., 31:695-707.

4. Sheikh1, F. A., Najeeb, S., Rather, A.G. and Banga, S., 2010, Resynthesis of Ethiopian mustard (Brassica carinata L.) from related digenomic species: An unexplored possibility. Agricultural Biotechnology and Sustainable Development., 2(2): 030-034.