MITOCHONDRIAL AND NUCLEAR-DNA VARIATION, GENOTYPE FINGERPRINTING AND GENETIC-RELATIONSHIPS IN LENTIL (LENS-CULINARIS MEDIK)

Mitochondrial DNA (mtDNA) and nuclear DNA (nuDNA) variations were exam ined in six cultivars of lens culinaris ssp. culinaris and two (mtDNA) or one (nuDNA) accession(s) of L. culinaris ssp. orientalis. Total le af DNA was digested with up to 15 restriction endonucleases, separated by agarose gel electrophoresis and trasferred to nylon membranes. To examine mtDNA variation, blots were probed with mtDNA coding for cytoc hrome c oxidase I (coxI) and ATPase 6 (atp6) of both wheat and maize a s well as apocytochrome b (cob) and Orf25 (orf25) of wheat. Sixteen co mbinations of mtDNA probes and restriction enzymes revealed 34 fragmen ts that discriminated between at least two lentil accessions. For nuDN A analysis, probes from cDNA and genomic DNA clones of lentil were use d to probe the same blots, and identified 46 diagnostic fragments from 19 probe/enzyme combinations. Each lentil accession could be unequivo cably distinguished from all others on the basis of both mitochondrial and nuclear DNA fragment patterns. The mitochondrial restriction frag ment similarities ranged from 0.944 to 0.989, with a mean of 0.970 but nuclear restriction fragment similarities varied from 0.582 to 0.987, with a mean of 0.743. The apparent genetic relationships among access ions differed according to the source of DNA examined, although the co mmercial varieties Laird, Brewer and Redchief showed similarly high le vels of mean similarity with both nuclear (0.982) and mitochondrial DN A (0.983).