Polymorphism among Sinorhizobium meliloti isolates native to the origins of alfalfa diversity differed in soil-climate characteristics

Abstract

Sinorhizoboium meliloti populations native to the 4 distinct gene centers (GC) of alfalfa were explored toward the tolerance to salinity, cryptic plasmid profiles and symbiotic properties. The significant correlations detected among nodule (N) and trapped (T) isolates related to the similar or distinct populations. more than 60 % N- and 77 % T-isolates tolerant to 3,5 % NaCl; salt tolerant N-isolates formed effective symbiosis with Medicago sativa and M. truncatula significantly more often. Isolates native to the GC area next to aral Sea had possessed the reduced level of salt tolerance in comparison with the isolates originated from Central asian, North-Caucasian and Europe-Siberian GC; that, has related to adaptation processes, which have ensured their viability in extremely salted soils.<img src="http://elibrary.ru/pic/1pix.gif" />

Molecular Phylogenetic Analysis of Salt-Tolerance-Related Genes in Root-Nodule Bacteria Species Sinorhizobium meliloti

“…Group C included betC sequences from Agrobacterium fabrum C58 and Rhizobium etli CFN42 (identity 78.97%; bootstrap 100%). Group B combined 26 betC sequences identified in S. meliloti strains and it had two clades, of which clade B-1 contained the sequence previously described as the "cb" allele according to PCR data [66]. The S. meliloti strain, which had this allele, was characterized by a reduced level of salt tolerance and reduced symbiotic efficiency under model salinity conditions.…”

Sinorhizobium meliloti: chromosomal types and genomic islands

“…Таким образом, установлено преобладание дивергентных последовательностей маркера М-III у штаммов из ПАГ по сравнению со штаммами из других генцентров, а также из агроценозов. Полученные результаты согласуются с ранее опубликованными нами данными [39,51,52] H BI = 1,37; H BII = 2,58). Следует указать, что в типе АII с наибольшими частотами были представлены 2 из 8 сочетаний (частоты -0,29 и 0,44), в типе BI -1 из 11 (частота -0,67), а в типе BII -13 из 15 сочетаний (идентифицированы у единичных штаммов; суммарная частота -0,87; данные не представлены).…”