TITLE:
Phylogenetic Diversity and Evaluation the Effectiveness of Indigenous Bradyrhizobium Strains for Myanmar Black Gram (Vigna mungo L. Hepper) Cultivars
AUTHORS:
Khin Myat Soe, Aung Zaw Htwe, Kyi Moe, Tomomi Abiko, Takeo Yamakawa
KEYWORDS:
Black Gram, Myanmar, 16S rRNA Gene, Bradyrhizobium, Nitrogen Fixation
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.11 No.2,
February
28,
2020
ABSTRACT: Black gram (Vigna mungo L. Hepper) is one of the main
leguminous crops that provide chief source of food. Several Bradyrhizobium species are able to induce effective nodules in black gram cultivars. In the
present study, we characterized forty isolates of indigenous black gram bradyrhizobia from Myanmar based on the
sequence analysis of the bacterial 16S rRNA gene. The sequence analysis
confirmed that all isolates were categorized and identified as the genus Bradyrhizobium and they were conspecific
with B. elkanii, B. sp., B. liaoningense, B. japonicum and B. yunamingense.
Almost all the collected isolates from major black gram growing regions of
Nyaunglebin Bago Regio, Chaungzon Mon State, Sittwe Rakhine State, Danubyu
Ayeyarwady Region and Launglon
Tanintharyi Region were identified as B. liaoningense.
At Danubyu Ayeyarwady Region and Pyinmanar Nay Pyi Taw Region, most of the
strains were identified as B. japonicum. On the other hand, more or less all the
isolates from Launglon Tanintharyi Region and Hpa-an Kayin State were related
to B. elkanii. However, all B. sp. strains were found in Salingyi
Sagaing Region black gram growing region. This is the first report describing Bradyrhizobium strains that were isolated from soil samples of major
black gram growing areas in Myanmar. Evaluation
of the effectiveness of Myanmar Bradyrhizobim strains isolated from soil samples of major black gram growing areas of Myanmar
for plant growth and nitrogen fixation was studied in pot experiments with completely randomized design and three
replicates. The nodule dry weight, shoot dry weight and acetylene reduction
activity of the plant inoculated with Bradyrhizobium elkanii LauBG38 were significantly higher in ARA per plant,
nodule and shoot dry weights than the other tested isolates in both Yezin-4 and
Yezin-7 black gram varieties. We expect that Myanmar Bradyrhizobium elkanii LauBG38 will be able to use as
Biofertilizer for black gram cultivars.