Molecular phylogenetic analysis of xanthomonas axonopodis pv. punicae isolates and bio-prospecting of selected botanicals and bio-agents against bacterial blight of pomegranate
Loading...
Date
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
UASD
Abstract
Pomegranate, Punica granatum L., regarded as the “Fruit of Paradise” is subjected to various
disease problems. Among diseases, bacterial blight caused by Xanthomonas axonopodis pv. punicae
(Hingorani and Singh, 1959) Vauterin et al. is one of the important diseases, which caused a great
havoc in recent years. The present investigation was undertaken to assess the diversity among
different isolates collected from different agroclimatic regions and to manage this disease effectively.
Water soaked lesions on leaves were produced after six days of inoculation. All the eighteen
isolates of Xap showed hypersensitive symptoms in Nicotiana tabacum leaves. Colony characters of
eighteen Xap isolates varied from circular and entire colony shape; slightly to highly mucoid character.
Among the varied temperature and pH levels tested, 28±10C and pH of 6.0 to 7.0 were found
optimum. All eighteen isolates of Xap produced fuscan pigment on LB agar after nine days of
incubation. Among the bactericides, K-Cycline was found effective against all isolates of Xap, which
was significantly superior to rest of the bactericides.
The multiplex polymerase chain reaction was performed using template containing DNA from
Xap targeting 16S rRNA and gyrB gene by 16S rRNA and gyrB specific primers. High intensity of
amplification of the gene specific products of 1537 bp and 491 bp corresponding to 16S rRNA and
gyrB were obtained at annealing temperature of 57.5º C for 1 minute as compared to other
temperatures.
Aqueous soapnut extract, Pseudomonas fluorescens strain [326(4)] and Pink Pigmented
Facultative Methylotroph (PPFM) strain 10L, CuSO4, ZnSO4, COC, Streptocycline showed inhibition
zone. Average fruit yield of two locations recorded significantly higher fruit yield per tree in T9 (COC
0.3% + streptocycline 0.05%) and T5 (P. fluorescens strain 326 (4) 1.0% + soapnut 5.0%) which
were on par with each other. The maximum C:B ratio was observed in COC + streptocycline
(0.3+0.05%).
Description
Keywords
null