Low genetic variability of Striga gesnerioides populations parasitic on cowpea might be explained by a recent origin

Dube, M-P and Belzile, F.J. (2010) Low genetic variability of Striga gesnerioides populations parasitic on cowpea might be explained by a recent origin. Weed Research, 50 (5). pp. 493-502.

[img] PDF - Published Version
Restricted to ICRISAT researchers only


Striga gesnerioides is an obligate root hemiparasitic plant that causes considerable yield losses to cowpea, an important crop legume of Sub-Saharan Africa. The use of resistant cultivars is the easiest and most effective method to control the parasite. Several cowpea cultivars exhibiting resistance have been identified during the last decades. However, most resistant cultivars show a differential response when grown in different countries across West Africa, suggesting that there are different races of S. gesnerioides. In this study, we investigated the genetic variability within and between 43 populations of five of the previously recognised races of the parasite present in West Africa. Amplified fragment length polymorphism (AFLP) markers were used on up to 10 individuals from each population. These markers showed almost no genetic variability within populations. The variability between the populations was also extremely low and did not allow discrimination of the five races. There was a certain geographical structure, but no ‘racial’ clustering could be seen. Even AFLP markers previously reported to be race-specific on another set of Striga populations proved unable to discriminate between races in this collection of populations. Possible causes of the low level of genetic variability include the hypothesis that this strain has only quite recently arisen. Such a low level of variability and the absence of specific markers for the virulence will have consequences on the evolution of the parasite and on the development of adequate control methods

Item Type: Article
Uncontrolled Keywords: witchweed;genetic variability;amplified fragment length polymorphism;parasitic plants;host specificity;Vigna unguiculata
Author Affiliation: avenue de la Médecine, Université Laval, Québec, Canada,
Subjects: Plant Production
Crop Improvement
Divisions: Other Crops
Depositing User: Mr. SanatKumar Behera
Date Deposited: 27 Jun 2012 13:40
Last Modified: 27 Jun 2012 13:41
Official URL: http://dx.doi.org/10.1111/j.1365-3180.2010.00804.x
URI: http://eprints.icrisat.ac.in/id/eprint/6302

Actions (login required)

View Item View Item