Environmental stresses such as drought, temperature, salinity, air pollution, heavy metals, pesticides, and soil pH are major limiting factors in crop production because they affect almost all plant functions. Soil salinization is a serious stress condition causing major problem for crop productivity. To combat this salinity stress, Plant growth promoting rhizobacteria (PGPR) is considered as innovative, effective and ecofriendly approach. Plant growth promoting rhizobacteria (PGPR) have various direct and indirect mechanisms which can be correlated with their ability to form biofilms, chemotaxis, and the production of exopolysaccharide, indole-3-acetic acids (IAA) and aminocyclopropane-1-carboxylate (ACC) deaminase Investigations on the interaction of PGPR with other microbes and their effect on the physiological response of crop plants under different soil salinity regimes are still at an incipient stage. An experiment was conducted to investigate the effect of PGPR on lowering down the salt stress. Treatments were control (T1), Salt tolerant isolate KH-1 (T2), Salt tolerant isolate KH-2 (T3), Salt tolerant isolate KH-3 (T4), PGPR-I (Pseudimonas) (T5), PGPR-II (Azotobacter) (T6). Rice was sown under saline conditions at Soil Salinity Research Institute, Pindi Bhattian. With the inoculation of salt tolerant PGPR, plant growth and yield was improved. Result showed significant increase in plant height, biomass and yield over control. Inoculation of salt tolerant isolate KH-2 produced maximum grain yield in rice (4267 kg/ha) followed by PGPR-II and it was statistically significant from all other treatments along with control. It is concluded that with the application of salt tolerant isolate (KH-2), there is significant increase in rice production.

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Iron (Fe), being an essential micronutrient, is necessary for human health and to maintain the integrity and development of the plant. In Fe-limiting conditions, plants and plant growth-promoting rhizobacterial (PGPR) have a siderophore production mechanism. Inoculation with seed soaking of such siderophore-producing bacteria can be a cost-effective biofortification technique. The current study includes the collection of rhizobacterial isolates from wheat, maize, sorghum, millet, and maize rhizosphere soil of Rawalpindi and Sargodha divisions. The screening of bacterial isolates for siderophore production through CAS-shuttle assay (quantitative) and CAS-agar (qualitative) was done. Isolates were further characterized for Fe and phosphorus solubilization, indole acidic acid (IAA) equivalents, and organic acid production. The growth chamber and field study was planned to evaluate the effectiveness of these isolates on the growth and yield parameters of wheat. Total bacterial isolates were 50, out of which 15 isolates were found significantly positive for the production of siderophore and solubilizing of nutrients. The (SPS10) produced a comparatively high percentage of 46.2 % siderophore units, as shown by results between positive isolates. Out of 15 positive, 7 isolates significantly improved root/shoot growth over control in the growth chamber study. Inoculation with siderophore-producing bacteria showed a significant increase in plant height, grain yield, spike length, grain weight, no. of tillers plant -1 , and wheat quality in a field trial. The results from the current study proposed that in the plant, rhizobacteria can also play a beneficial role in nutrient translocation to plants efficiently and nutrients uptake from the soil insoluble form.

Despite soil having an abundance of iron (Fe), it is unavailable for proper plant growth and development. One of the mechanisms plants use to deal with iron deficiency is the uptake of iron by chelating phytosiderophores. Pseudomonas fluorescence can produce pyoverdine-type siderophore and has potential application in agriculture as an iron chelator. Therefore, bacterial isolates collected from different areas of district Faisalabad were screened for their fluorescent, siderophore production and indole acetic acid equivalents. After selecting efficient strains from a screening test, they were evaluated for improving wheat and maize production under field conditions. The results showed that out of 15 isolates, 7 were found to have significant plant-beneficial microbial traits. Efficient strains promoted grain yield by 24.2% and 20.2%, plant height by 30.9% and 23.7%, total grain weight by 25.3% and 13.4% over control in wheat and maize, respectively. Similarly, significant improvements in the number of grains per cob/spike were also observed. Analyses of grain iron contents depicted 67% increase as compared to control in  for maize. Therefore, based on the results, it is concluded that bio-fortification of cereal crops through fluorescent producing siderophoric microbes is an effective strategy favorable for plant growth and development through nutrient solubilization/mobilization.

Crop yields are highly affected due to physiochemical properties of soil and climatic conditions of the region. The yield of the crop is drastically impacted in terms of final economic product due to problems which occurs in life cycle of the plant under the stress conditions like, stunted growth, permanent wilting, and delay in leaf initiation as well as oxidative stresses at molecular level. Maize (Zea mays L.), widely used as staple food has an ample amount of fats and fibres. Salt stress decreases maize yield and in this regard a hydroponic study was carried out to screen maize genotypes against two salinity stress levels i.e., 10 mol m-3 NaCl and 100 mol m-3 NaCl under hydroponic conditions. Nine (09) hybrid genotypes, i.e., Pioneer 3335 (V1), Pioneer 32F10 (V2), Syngenta 8441 (V3), Pioneer: 33H25 (V4), Pioneer: 3233 (V5), Monsanto 6142 (V6), Syngenta 8711 (V7), Monsanto 6528 (V8), Pioneer 31P41 (V9) were selected for experiment. Statistically, the analysis showed the highest root-shoot length, root fresh-dry weight, and shoot fresh-dry weight with V3 (Syngenta 8441) and the minimum with V1 (Pioneer 3335). The results showed that root length increased by 35% shoot length increased by 34% while total length was enhanced by 34% in syngenta 8441. The results clearly depicted that the best suited variety for salt affected areas can be recommended as Syngenta 8441 whereas the least tolerant was Pioneer 3335 in terms of physiological, physical, and growth characteristics.