Pandove, GulabJagjot Kaur2018-01-172018-01-172017http://krishikosh.egranth.ac.in/handle/1/5810039548The present investigation was undertaken to evaluate the effect of liquid inoculants of Azotobacter sp. and Streptomyces badius on agronomic traits of wheat (Triticum aestivum L.) under different planting dates by mitigating the impact of climate change. The cultures of Azotobacter sp. and Streptomyces badius were procured from the Department of Microbiology, Punjab Agricultural University, Ludhiana and evaluated for their plant growth promoting traits and physio-chemical properties. The quantity of phosphate solublization, IAA, gibberellic acid, ammonia production by Azotobacter sp. was 21.74 ± 0.4 µg/100ml, 10.75 ± 0.3 µg/ml, 77.86 µg/ml and 27.68 ± 0.7 µmole/ml respectively and by Streptomyces badius was 28.73 ± 0.4 µg/100ml, 13.39 ± 0.8 µg/ml, 108.44 ± 1.5 µg/ml and 32.48 ± 1.6 µmole/ml respectively. The siderophore production was exhibited by Streptomyces badius only. It produced 104.89 ± 2.3 µg/ml of catechol type and 62.84 ± 0.5µg/ml of hydroxamate type siderophores. Both the cultures were also found positive for ACC-deaminase activity and were able to withstand high concentration of NaCl (Azotobacter sp. upto 25% and Streptomyces badius upto 15%), temperature as high as 50oC and wide range of pH from 2-12. Liquid inoculants of Azotobacter sp., Streptomyces badius and combination of both formulated using 2% PEG showed maximum viability after 180 days as compared to other formulations at room and refrigerated temperature. The field experiment was conducted at Regional Research Station, Bathinda during two consecutive years i.e. 2015-16 and 2016-17. The main plots treatment consisted of five planting dates (25th October, 10th November, 25th November, 10th December and 25th December) and four liquid inoculants treatments (T1:100% RDF (control), T2:100% RDF + seed bacterization with liquid inoculants, T3:75% RDF + seed bacterization with liquid inoculants and T4:75% RDF + seed bacterization with liquid inoculants + foliar application of liquid inoculants at critical stages of wheat) in subplots. The treatments of twenty combinations were tested in split plot design with three replications. Maximum plant height, chlorophyll content, shoot and root dry weight, effective tillers, spike length, grains per spike, 1000 grain weight was attained by the crop planted on 10th November followed by 25th November and minimum by crop planted on 25th December (very late planting). Significantly highest grain yield was obtained in 10th November planting (58.86 q/ha) and was at par with 25th November planting. Amongst the liquid inoculants treatment, 75% RDF + seed bacterization with liquid inoculants + foliar application of liquid inoculants at critical stages of wheat was found superior in all growth and yield attributing parameters at each date of planting followed by T3, T2 and T1 . The T4, T3 and T2 treatments resulted in 4.79, 3.47 and 1.61 per cent more grain yield over T1. Thus it can be concluded that liquid inoculants of Azotobacter sp. and Streptomyces badius can enhance growth and yield of wheat by mitigating the impact of climate change. This combination may be used as an efficient PGPR for wheat production.ennullThesis