Root Associated Bacillus sp. Improves Growth, Yield and Zinc Translocation for Basmati Rice (Oryza sativa) Varieties

Abstract

Plant associated rhizobacteria prevailing in different agro-ecosystems exhibit multiple traits which could be utilized in various aspect of sustainable agriculture. Two hundred thirty four isolates were obtained from the roots of basmati-385 and basmati super rice varieties growing in clay loam and saline soil at different locations of Punjab (Pakistan). Out of 234 isolates, 27 were able to solubilize zinc (Zn) from different Zn ores like zinc phosphate [Zn3 (PO4)2], zinc carbonate (ZnCO3) and zinc oxide (ZnO). The strain SH-10 with maximum Zn solubilization zone of 24 mm on Zn3 (PO4)2ore and strain SH-17 with maximum Zn solubilization zone of 14–15 mm on ZnO and ZnCO3ores were selected for further studies. These two strains solubilized phosphorous (P) and potassium (K) in vitro with a solubilization zone of 38–46 mm and 47–55 mm respectively. The strains also suppressed economically important rice pathogens Pyricularia oryzae and Fusarium moniliforme by 22–29% and produced various biocontrol determinants in vitro. The strains enhanced Zn translocation toward grains and increased yield of basmati-385 and super basmati rice varieties by 22–49% and 18–47% respectively. The Zn solubilizing strains were identified as Bacillus sp. and Bacillus cereus by 16S rRNA gene analysis.

Isolated Bacillus subtilis strain 330-2 and its antagonistic genes identified by the removing PCR

“…Plates were incubated at 28 °C. The inhibition of fungal growth was monitored by recording the diameter of the inhibition zone (mm).The percentage of inhibition was calculated using the following formula 83 .where “C” is the mycelium diameter (cm) of the fungus growing on the control plates (without bacteria) and “T” is the mycelium diameter (cm) of the fungus growing in the bacterial-treated plates. The experiment was repeated thrice with three biological replicates each time.…”

Bacillusspecies in soil as a natural resource for plant health and nutrition

“…Zinc‐solubilizing bacteria (ZSB) are known to produce various kinds of organic and inorganic acids and chelating compounds, through which complex unavailable forms of zinc are made available to plants (Kumawat et al ). Well‐known zinc solubilizers in the genus Bacillus are B. aryabhattai , B. subtilis , B. thuringiensis and B. tequilensis (Shakeel et al ; Singh et al ). The role of Bacillus in iron has already been discussed in the siderophore section of this review.…”

“…Two multifaceted PGPR strains Bacillus sp. and B. cereus with ability to solubilize P, K and Zn and activities against Pyricularia oryzae and Fusarium oryzae have shown increased yield and zinc translocation towards grains in basmati rice varieties (Shakeel et al ). An IAA‐producing PGPR strain, B. altitudinis FD48, when inoculated to rice was shown to modify root architecture by regulating auxin‐responsive genes (Ambreetha et al ).…”

Plantibacter flavus, Curtobacterium herbarum, Paenibacillus taichungensis, and Rhizobium selenitireducens Endophytes Provide Host-Specific Growth Promotion of Arabidopsis thaliana, Basil, Lettuce, and Bok Choy Plants

“…Biofertilizers, which contain beneficial microorganisms or natural compounds originating from microbes (16)(17)(18), are sustainable alternatives to stop or reduce the use of chemical fertilizers in organic and conventional agricultural systems. Biofertilizers are also advantageous in that they are more cost-efficient, provide a renewable source of nutrients, and can provide plants with a multitude of different benefits (19)(20)(21)(22)(23). Currently, biofertilizers are most commonly used as a means of improving crop nitrogen and phosphorus uptake through the application of PGPB like Azotobacter, Azospirillum, Bacillus, and Rhizobium species (11,(24)(25)(26)(27)(28)(29)(30).…”