Diversity of sugarcane root-associated endophytic Bacillus and their activities in enhancing plant growth.

Plant tissues are the reservoirs of beneficial and harmful microbes that regulates plant growth. In the present study, we investigated the diversity, function and colonization of sugarcane roots associated with Bacillus spp. A total of 20 Bacillus strains were isolated and identified by 16S rRNA gene sequencing, and their genetic diversity was examined by BOX, ERIC, REP, (GTG)5 PCR techniques. Among all Bacillus isolates, 65% showed indole acetic acid-like compounds production, 50% solubilized phosphorus and 25% of the isolates were able to secrete siderophore. Moreover, all 20 Bacillus isolates showed antifungal activity against eight fungal pathogens and 11 of them (55%) antagonized tomato grey mold. Based on the plant growth-promoting traits and antifungal potential, isolate Y8 was selected for root and plant tissue colonization assays and a greenhouse-level sugarcane growth promotion study. Fluorescence microscopy results confirmed that isolate Y8 has a strong ability to colonize in the sugarcane root and leaves, and the root surface association of Y8 was confirmed by scanning electron microscopy. Furthermore, greenhouse experimental results demonstrated that Y8 has a significant effect on enhancing sugarcane biomass and root length. Endophytic Bacillus strains have growth-promoting properties and anti-fungal ability that can enhance plant fitness in an eco-friendly manner. Endophytic Bacillus strains would be a potential alternative to chemical fertilizer as well as a biocontrol agent in the future.

Wang Z ，Yu ZX ，Solanki MK ，Yang LT ，Xing YX ，Dong DF ，Li YR ... -  《-》

Plant growth promoting and antifungal activity in endophytic Bacillus strains from pearl millet (Pennisetum glaucum).

Kushwaha P ，Kashyap PL ，Srivastava AK ，Tiwari RK ... -  《-》

Screening and characterization of endophytic Bacillus and Paenibacillus strains from medicinal plant Lonicera japonica for use as potential plant growth promoters.

Zhao L ，Xu Y ，Lai XH ，Shan C ，Deng Z ，Ji Y ... -  《-》

Culturable endophytic bacteria of Camellia species endowed with plant growth promoting characteristics.

Tea (Camellia sinensis (L.) O. Kuntze) is an economically important caffeine-containing beverage crop with massive plantation in the Northeast corner of the agroclimatic belt of India. The main aim of the work was to isolate, identify and characterize the native plant growth promoting endophytes associated with tea for future microbe based bioformulation. A total of 129 endophytic bacteria were isolated and characterized for plant growth promoting traits such as indole-3-acetic acid (IAA), phosphate solubilization, ammonia production, biocontrol traits like siderophore and extracellular enzyme production. BOX-PCR fingerprinting was used to differentiate the various bacterial isolates obtained from six different tea species. 16S rRNA sequencing and blast analysis showed that these isolates belonged to different genera, that is, Bacillus, Brevibacterium, Paenibacillus and Lysinibacillus. Lysinibacillus sp. S24 showed the highest phosphate solubilization and IAA acid production efficiency of 268·4 ± 14·3 and 13·5 ± 0·5 µg ml-1 , respectively. Brevibacterium sp. S91 showed the highest ammonia production of 6·2 ± 0·5 µmol ml-1 . Chitinase, cellulase, protease and pectinase activities were shown by 4·6, 34·1, 27·13 and 13·14% of the total isolates, respectively. Similarly, 41% of the total isolates were positive for 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity. Further, the potent PGP isolates, S24 and S91 were able to enhance the vegetative parameters such as dry/fresh weight of root and shoot of tea plants in nursery conditions. Our findings corroborate that tea endophytic bacteria possess the potential to demonstrate multiple PGP traits both, in vivo and in vitro and have the potential for further large-scale trials. The exploration of tea endophytic bacterial community is suitable for the development of bioformulations for an integrated nutrient management and thus sustainable crop production and decreasing the hazardous effects of chemical fertilizers on the environment and human health.

Borah A ，Das R ，Mazumdar R ，Thakur D ... -  《-》

Epicoccum nigrum P16, a sugarcane endophyte, produces antifungal compounds and induces root growth.

Fávaro LC ，Sebastianes FL ，Araújo WL 《-》