Effect of chromium on growth attributes in sunflower(Helianthus annuus L.)

Heavy metal soil pollution takes place when the metal concentration of soil exceeds natural background level and causes ecological destruction and deterioration of the environment.In the present study,a pot experiment was conducted to evaluate the effect of chromium-contaminated soil in sunflower(Helianthus annuus L.)growth attributes.Three different levels of chromium(Cr)i.e.,20, 40,and 60 mg/kg were applied to three varieties of sunflower(G-3,G-9,and G-59).The results of morphological,chemical,and yield p...

Utilizing the γ-Irradiated Sodium Alginate as a Plant Growth Promoter for Enhancing the Growth,Physiological Activities,and Alkaloids Production in Catharanthus roseus L.

Sodium alginate is a polysaccharide that is largely obtained from the brown algae （Sargassum sp.）.It has been used as a wonderful growth promoting substance in its depolymerized form for various plants.The aim of this study was to find out the effects of various concentrations of γ-irradiated sodium alginate （ISA）,viz.,deionized water （control,T0）,20 （T1）,40 （T2）,60 （T3）,80 （T4）,and 100 ppm （T5） on the agricultural performance of Catharanthus roseus L.（Rosea） in terms of growth attributes,photosynthesis,physiological activities,and alkaloid production.The present work revealed that ISA applied as leaf-sprays at concentrations from 20 to 100 ppm might improve growth,photosynthesis,physiological activities,and alkaloid production in C.roseus L.significantly.Of the various ISA concentrations,80 ppm proved to be the best one compared to other concentrations applied.

Multi-strain Inoculation with PGPR Producing ACC Deaminase is More Effective Than Single-strain Inoculation to Improve Wheat (Triticum aestivum) Growth and Yield

Rhizosphere bacteria that colonize plant roots and confer beneficial effects are referred as plant growth promoting rhizobacteria(PGPR).Among all PGPR,some rhizobacteria have an ability to produce ACC deaminase enzyme.This enzyme catalyzes stress ACC into a-ketobutyrate and ammonia instead of letting it to be converted to ethylene.Ethylene level rises in plants under stress conditions i.e.,drought,salinity,poor soil fertility etc.As poor soil fertility is a big hurdle to achieve the optimum yield of crops,inoculation of ACC deaminase PGPR can overcome this problem to some extent.The aim of the current study was to examine the influence of multi-strain and single-strain inoculation of different ACC deaminase producing PGPR on wheat growth and yield.There were three PGPR strains,Enterobacter cloacae,Serratia ficaria and Burkholderia phytofirmans which were used as consortia and single-strain inoculations.The results showed that inoculation of E.cloacae+S.ficaria+B.phytofirmans significantly increased plant height(63%),spike length(61%),number of spikelets spike-1(61%),number of grains spike-1(131%),1000 grains weight(33%),grains yield(71%),straw yield(71%)and biological yield(68%)of wheat as compared to control.A significant improvement in N(37 and 200%),P(46 and 166%)and K(39 and 61%)of seeds and shoot respectively,validated the efficacious and more effective role of multi-strain(E.cloacae+S.ficaria+B.phytofirmans)inoculation over control.It is obviously concluded that multi-strain ACC deaminase producing PGPR inoculation is a better approach as compared to single-strain inoculation for the improvement in growth and yield of wheat.

Role of methylotrophic bacteria in managing abiotic stresses for enhancing agricultural production

Abiotic stresses are a significant factor that considerably limits plant growth and productivity.Methylotrophs are an essential group of bacteria that utilize volatile carbon compounds,are prolific colonizers of different plant parts,and play a vital role in plant growth promotion(PGP)under stress conditions.Numerous rhizospheric and phyllosphere methylotrophs have been reported to exhibit PGP activities with superior stress-tolerating capacity against drought,heavy metal,salinity,high and low temperatures,solar ultraviolet radiation,and other harsh environmental conditions.Methylotrophs promote plant growth through N2 fixation,phosphate solubilization,production of phytohormones(i.e.,auxins,gibberellins,and cytokinins),1-aminocyclopropane-1-carboxylic acid(ACC)deaminase activity,siderophore,ammonia production,and secondary metabolites.The production of these compounds by methylotrophs protects a plant against adverse environmental conditions and influences its productivity.This review discusses the role methylotrophs play in managing various abiotic stresses,how they help mitigate these stresses,and how they improve agricultural productivity.