Salt stress is a major environmental factor which adversely affects the crop yield and quality. However, adequate regulation of mineral nutrients may ameliorate the deleterious effects of salts and help to sustain crop productivity under salt stress. Salt-sensitive (SPF 213) and salt-tolerant (HSF 240) sugarcane genotypes were grown in gravel at 0 and 100 mM NaCl by supplying 0, 1.4 mM, 2.1 mM and 2.8 mM of Si as calcium silicate. Results revealed that plants treated with NaCl alone showed a significant (P≤0.05) reduction in dry matter production, K + concentration, cane yield and juice quality in both genotypes but the magnitude of reduction was relatively more in salt-sensitive genotype than salttolerant. Addition of Si significantly (P≤0.05) reduced the uptake and translocation of Na + but increased K + concentrations particularly in shoots of both sugarcane genotypes. Cane yield and yield attributes were significantly (P≤0.05) higher where Si was added. Juice quality characteristics were significantly (P≤0.05) improved in salt-sensitive and salt-tolerant sugarcane genotypes with the application of Si. The results suggested that added Si interacted with Na + , reduced its uptake and transport to shoots and consequently improved cane yield and juice quality in salt-sensitive and salt-tolerant sugarcane genotypes under salt stress.

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Rhizobium besides its nodule formation characteristic with members of Fabaceae family has been recognized for its great root colonizing ability and growth hormone production potential. In addition to nitrogen fixation in legume plants, rhizobia considered as beneficial tools and act as plant growth promoting rhizobacteria (PGPR) with many non-legumes. Present study was elucidated to determine the comparative role of Rhizbium sp for growth promotion of sunflower. Rhizobia were isolated from five different legumes (mungbean, barseem, lentil, chickpea, and vegetable pea) and checked for their auxin production efficiency. Rhizobial isolates Cp-4 showed maximum auxin potential (5.37 µg mL-1 IAA equivalents).Results showed that inoculation of all rhizobial isolates caused significant increase in growth and physiological parameters of sunflower plants. While prominent results were found with inoculation of mungbean rhizobial isolate Mb-2 which increases the chlorophyll a, N, P, fresh and dry matter of sunflower significantly by 8.34, 4.9, 36, 31, and 34%, respectively in comparison to uninoculated control plants. Hence, present study concluded that Rhizobium sp can be successfully used as PGPR in non-legumes after thorough investigations.

Legumes compensate mineral fertilizer by fixing nitrogen due to the specialized structures i.e. nodules by Rhizobium species. Literature revealed that legumes fixed nitrogen due to Rhizobium inoculation from 50-300 kg NPK ha-1 year-1. Rhizobium besides nitrogen fixation, solubilized phosphates, produced growth hormones and due to its root colonizing ability improved the growth and yield of non-legumes also and performed as plant growth promoting rhizobacteria (PGPR). Study was conducted to assess the relative efficiency of Rhizobium species for the growth and yield of cotton. Different isolates of five species of Rhizobium species responsible for different nodule formation in legumes were assessed for the auxin biosynthesis potential as IAA equivalents and isolates having higher values for IAA equivalents were used for experimentation. Results revealed that isolates of Rhizobium species improved the growth and physiological parameters of cotton. Higher values were root/shoot length and mass were observed with Rhizobium species of berseem (Br5). Bacterial inoculation with isolate (Br5) produced 60.94, 64.40 g shoot/root mass that is 16.70 and 23.80 % higher than control and percent increase improvements of cotton shoot/root length with Br5 i.e. 18.3, 24.8 % higher than that of control. Higher values of IAA equivalents were observed in root/shoot content of cotton with isolate of Br5. Bacterial inoculation improved the plant height, boll weight, number of bolls plant-1 and seed cotton yield with Br5 inoculation. The chlorophyll content, photosynthetic rate, transpiration rate and photo active radiation were also higher in the inoculated treatments. Results of present study clearly demonstrated that different isolates of Rhizobium species improved the growth and yield parameters of cotton and thus Rhizobium sp can be effectively utilized as bacterial inoculants in non-legumes.

For growth or development of pulses, biotic and abiotic environmental factors are more conspicuous under stress conditions. For the survival against abiotic stresses, salicylic acid (SA) is reported a universal remedy. At the Soil Bacteriology Section, Ayub Agricultural Research Institute, Faisalabad, a pot study was conducted to monitor the role of Plant Growth Promoting Rhizobacteria (PGPR) and Salicylic acid in chickpea under salt stress. Eight treatments including control PGPR inoculation and Salicylic acid with their different combination were used. Results revealed that positive response of PGPR on productivity of chickpea but more enunciated response about grain yield was observed with the combined application of SA and PGPR compared to control. Growth parameters i.e root length, root mass, number of nodules and shoot mass were highly affected where SA was applied along with PGPR. From the study, it is proposed that under salt stress the combination of SA + PGPR can be a suitable practice for more production of chickpean Pakistan.