The microbial dynamics expressed in terms of culturable microbial populations i.e. bacteria, fungi, actinomycetes and Azotobacter were measured after 33 years of continuous application of mineral fertilizers and amendments to an acid alfi sol. The bacterial, fungal and Azotobacter populations were maximum in plots treated with mineral fertilizers and FYM (100%NPK+FYM) while actinomycetes population was maximum in mineral fertilizes and lime treated plots (100%NPK+Lime). The bacterial population decreased and fungal population increased with increasing levels of NPK i.e. from 50% to 150%NPK. Bacillus species of bacteria and Gliocladium, Aspergillus and Rhizopus species of fungi were the main dominating culturable microorganisms in all the treatments. The FYM and lime amended plots sustained crop productivity and microbial populations at higher levels than rest of the mineral fertilizer treatments. The nitrogenous fertilizers alone had the most deleterious effect on crop productivity and the biological soil environment.

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Cotton is an important commercial crop grown in India. It occupies an area of about 12.7 million hectares and is grown both in irrigated as well as rainfed tracts. In such situations, roots are very important organ for plant growth and development, since they act as anchors, providing mechanical support, and chemical extractors for the growing plant. Root length density sets the proportion of water uptake both under wet conditions and dry soils. Cotton plants with efficient root system capture water and nutrients from soil having these features of longer tap root. It is widely accepted that breeding efforts on aboveground traits are not sufficient to the necessary yield advantage. Shifting the emphasis to analyzing the root system would provide an additional means to enhance yield under changing climatic condition. Belowground image analysis studies point to the importance of root system architecture for optimizing roots and rhizosphere dynamics for sustainable cotton production. In this review, we describe the cotton root biological context in which root-environment interactions providing an overview of the root growth morphology species wise, phytohormone action that control root growth, root anatomical significance in drying soils, biotic and abiotic stresses involved in controlling root growth and environmental responses.

Three promising genotypes (CAZRI 75, CAZRI 2178 and CAZRI 2221) of buffel grass (Cenchrus ciliaris L.) were evaluated for maximization of seed production by imposing different cutting management practices, i.e. uncut (control), single cut at 30 and 45 days of sowing/regeneration and at 50 % flowering during 2010-2013 under arid conditions of Thar desert. Maximum pure seed yield (PSY) of 67.6 kg/ha was produced by CAZRI 2221 in 2011, 53.5 kg/ha in 2012 and 72.0 kg/ha in 2013 with average of 64.4 kg/ha, which was 131.7 and 32.2 % higher than CAZRI 75 and CAZRI 2178, respectively. Highest PSYs were obtained from uncut crop in all the years, and average over the last 3 years showed that the PSY (86.3 kg/ha) from uncut treatment was 117.4, 283.6 and 119.0 % higher than the crops cut at 30 and 45 days and 50 % flowering, respectively. Average over the last 3 years of crop growth also showed that plant height, number of fertile tillers/meter row length, spike length, 1,000-seed weight, seeds/spike, seed weight/spike and dry matter yield were maximum with no cutting. Reduced dry matter yield was recorded in the years 2012 and 2013 when cuttings were imposed. The findings of the investigation showed that CAZRI 2221 was the best seed yielder and higher seed yields were obtained from the uncut treatment.