Genetic and chemical analysis of seed coat of cowpea and bean cultivars in relation with resistance to weevil pest [electronic resource].

Includes references.

The objective of this work was to evaluate the genetic variability among 6 cowpea (vigna unguiculata) cultivars differing in their resistance to callosobruchus maculatus (F,) weevil. Two resistant bean cultivars were used to compare between the senitive, moderate tolernant and highl tolerant cowpea cultivars. The differentiations were performed by using random amplified polymorphic DNA (RAPD) marker, protien concentration and organic and non organic components in seed coat. Six polymorphic primers were identified, resulting in different informative band. Based on polymorphic profiles, 3 clusters were farmed, Clustering was mainly affected by theresistance to weevil pest, the sensitive cowpea cultivars were sparated in one group, the moderate tolerant and high I tolerant cultivars came in separate group and finally, the resistant bean cultivars separated clearly in one distinct group. The most interesting result was represented by concentration of total protein in the seed coat. the protein concentration in the resistant bean cultivars were approximately 50% less than concentration in each of the moderate tolerant and sensitive cultivars of cowpea. ferric ions were about 25 % less than the moderate tolerant and sensitive cultivars.The concentrations of calcium and potassium in seed coats were higher in the resistant beans than in cowpea cultivars. Cobalt was about' 4 times higher in resistant bean than in the sensitive and moderate tolerant cowpea cultivars, which may playa major role in seed resistance to weevil.

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