Two successive experiments were carried out at Ras Sudr Agricultural
Research Station of ORC during 2000 and 2001 growth seasons to investigate the
mean performance (adaptability) of six Egyptian cotton varieties to saline conditions of
Wadi Sudr. Also to evaluate the genetic variation and genetic relationships between
varieties using random amplified polymorphic DNA (RAPD) markers. Long staple
varieties Giza 90 then Giza 83 followed by Deodera were more adapted to saline
conditions and attained the significant highest values of yield and its attributes.
Meanwhile extra long staple ones Giza 77 as well as Giza 45 were less adapted and
exhibited a significant lower values. Five random 10-mer primers were used to amplify
DNA via polymerase chain reaction (PCR) and 55 RAPDs were generated. The five
primers detected polymorphism in all six cotton varieties. Out of the total amplified
bands 60 % were polymorphic. Similarity matrix was generated from the RAPD
results as compared by using Nei and Li's (1979) coefficient. Giza 77 was the least
similar one with other studied varieties whereas Giza 90, Giza 83 were the greatest
similar varieties. Dendrogram generated. by UPGMA analysis, detected that the more
adapted varieties to saline conditions. long staple varieties Giza 90, Giza 83 and
Dendera grouped together; Giza 45 the extra long staple variety which and Giza 85
the long staple variety showed that significant lower yield and its attributes grouped
together whereas Giza 77 extra long staple variety and lowest adapted or significant
lowest yielding ability did not duster with any other variety tested. The results obtained could be used for selection the suitable parents for
breeding program for improving fiber qualities and its adaptability under saline j
conditions.