title: Use of DNA marker to select well-adapted Phaseolus-symbionts strains under acid conditions and high temperature.
abstract: Soil acidity and high temperature contribute to the failure of nodulation in the common bean. It is therefore urgent to select strains with a high competitive ability under these stress conditions. Two Egyptian Rhizobium etli strains, EBRI 2 and EBRI 26, were examined against Rhizobium tropici CIAT 899G labeled with the gus (beta-glucuronidase) reporter gene. EBRI 2 and EBRI 26 were less competitive than CIAT 899G under acid conditions with both the Egyptian cultivar Giza 3 and the Colombian cultivar Rab 39. However, EBRI 2 and EBRI 26 gave higher nodule occupancy (78% and 62.5, respectively) than the nodule occupancy (18.5% and 35%) obtained by CIAT 899G at 35 degrees C with cultivar Giza 3. Soil acidity (pH 5.8) was less detrimental to the nodule occupancy of EBRI 2 than EBRI 26 when they tested in competition with CIAT 899G.
authors.affiliation: Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, Mubarak City for Scientific Research and Technological Applications, New Borg El-Arab City, Alexandria, Egypt. yabdelall@yahoo.com
authors.forename: Abdelaal
authors.initials: A
authors.lastname: Shamseldin
mesh_terms: D018744:DNA, Plant / Q000235:genetics*; D005819:Genetic Markers / Q000235:genetics*; D006863:Hydrogen-Ion Concentration; D027805:Phaseolus / Q000145:classification* / Q000166:cytology / Q000502:physiology*; D012987:Soil; D013045:Species Specificity; D013696:Temperature
chemical_list: D018744:DNA, Plant; D005819:Genetic Markers; D012987:Soil