Studies on endophytic Burkholderia sp. from sugarcane and its screening for plant growth promoting potential

Abstract

KEYWORDS Burkholderia MALDI-TOF MS Plant growth promotion Phylogeny ABSTRACTThe occurrence of Burkholderia genus as plant endophyte indigenous to locally cultivated sugarcane crop was studied. Totally 22 endophytic isolates were obtained from TB-T medium plates of which 10 were found to be putatively endophytic in sugarcane. The morphological, biochemical and MALDI-TOF MS analysis were done and 5 endophytic Burkholderia sp. isolates were identified. Among them, the isolate Burkholderia sp. ES4 shown maximum; diazotrophic activity (total nitrogen: 11.9 mg g -1 of malate; nitrogenase activity: 578.3 n mol C2H4 released h -1 mg -1 protein), mineral solubilization activity (10.2mm, 8.2mm and 3.2 mm solublization zone of P, ZnO and CaCO3 respectively; available phosphorous: 0.72mg ml -1 ), antagonistic activity (54.56 percent inhibition of Colletotrichum falcatum mycelium) and phytohormone production (IAA (16.09 µg ml -1 ); GA (10.54 µg ml -1 )), thereby revealing its plant growth promoting potential. The 16S r RNA gene sequence of the isolate Burkholderia sp. ES4 was sequenced and its phylogenetic analysis shown that the isolate forms a monophyletic subclade within the plant-beneficial-environment" (PBE) Burkholderia group. Thus a potent native plant endophytic strain, Burkholderia sp. ES4 that could be developed as biofertilizer inoculum for sugarcane crop, was obtained in this study.

Glyphosate induced toxicity to chickpea plants and stress alleviation by herbicide tolerant phosphate solubilizing Burkholderia cepacia PSBB1 carrying multifarious plant growth promoting activities

“…Considering the threat that herbicide adversely affects the production of legumes on one hand and herbicide tolerant soil microflora may enhance the legume production even under herbicide stressed soil, on the other hand, the current research was designed. Although, B. cepacia is a known pathogen, yet, it also has some agronomic importance and have previously been used as a PGPR due largely to its nitrogen fixing, phosphate solubilizing and ACC deaminase activity (Sandanakirouchenane et al 2017;Rahman et al 2017;Arthee and Marimuthu 2017) for enhancing the production of crops. For instance, B. cepacia as biofertilizer have been applied to protect crops from damaging impact of fungal pathogens leading eventually to the increase in crop yields (Holmes et al 1998).…”

Plant growth promotion effects of rhizopheric and endophytic bacteria on sugarcane cultivated on Acrisols of Tay Ninh province, Vietnam

“…Through the pot experiment results, following trends can be drawn: (1) In the absence of using chemical N, P fertilizers, both strains of bacteria had good effects on all parameters compared to the treatment without using bacteria. (2) The fertilization level of 25% N and P fertilizers in combination with bacteria did not have a significant effect on the growth and yield of sugarcane, so these treatments were reduced in the field experiment later. (3) CT4bd strain, when used in combination with N, P fertilizer, increased stem diameter, degree Brix and commercial cane sugar.…”

“…The field experiment results indicated that for the sugarcane variety K95-156 grown on gray soil in Tay Ninh province, both bacterial strains CT4bd (Serratia oryzae) and TPD3b (Bacillus subtilis) had capacities of promoting plant growth under field condition and could be summarized as following: (1) The strain CT4bd combined with 75 -100% N, P fertilizers had good performance on internode number, cane yield, degree Brix , CCS and sugar yield; (2) The strain TPD3b combined with 75 -100% of N, P fertilizers had good effects on parameters including internode number, degree Brix and CCS; (3) The combination of 2 strains CT4bd and TPD3b combined with 75% of N, P fertilizers had good effects on indicators of internode index, Brix degree, sugar content and actual sugar yield.…”

“…While N fertilizer used for one hectare was in the range of from 120 to 300 kg. In average, crops only used 50 per cent of N fertilizer applied [2]. There were many reasons for the low fertilizer use efficiency such as high soil nitrification rates and N leaching and denitrification by weather extremes [3].…”

“…Besides these, endophytic and rihzopheric bacteria could benefit the sugarcane through other mechanisms that promoted availability and uptake of mineral nutrients [7]. Specially, colonization of endophytic and rhizopheric bacteria did not provoke any host plant defense [2].…”