Dr. B.P. DhyaniAKANSHA SINGH2023-12-252023-12-252022-08https://krishikosh.egranth.ac.in/handle/1/5810204379Name: Akansha Singh Id. No.: A-1763/17 Major: Soil Science & Agricultural Chemistry Minor: Agronomy Year of Admission: 2017-18 Degree Program: Ph.D. (Soil Science & Agricultural Chemistry) Thesis Title: “Effect of Microbial Inoculants and Biochar on Phosphorus Fractions in Different Soils” Advisor: Dr. B.P. Dhyani, Professor, Soil Science & Agricultural Chemistry ABSTRACT The study was conducted on four types of soils collected from various locations, in a pot culture experiment during Kharif and Rabi season to find changes in phosphorus and different soil properties with the application of biochar, phosphate solubilizing microbes (PSMs) including bacteria or fungi and microbes with biochar in different treatments. Among the different soils one soil was acidic while another three were alkaline. The bacteria Bacillus spp. (B1) and Pseudomonas spp. (B2) used were isolated from Soil-1 and Soil-4 while fungal isolates Aspergillus spp.(F1) and Penicillium spp. (F2) were taken from outside. The biochar used was made by sugarcane bagasse and rice residue having alkaline pH. The soil samples in the pot were used for analysis at three times after treatment inoculation at an interval of 25th, 50th and 75th days after inoculation (DAI). Results revealed that PSMs supported P solubilization so the inorganic P fractions i.e. Saloid-P shows maximum content at 25th DAI, the Fe-P, Al-P and Ca-P content decline over control at 25th DAI due to these treatments in all soils while content of these fractions increases over control due to biochar application. The main effect of PSMs was there of fungal inoculants for acidic soil (Soil-1) while bacterial effects were dominant in Soil-2 to Soil-4. The best treatment effect in all soils was recorded for biochar with microbes (bacteria and fungi) for all analyzed parameters like pH, EC, Organic Carbon (OC), available N, P and K, microbial biomass carbon (MBC) and enzyme activity (acid and alkaline phosphomonoesterase). The Total P and Organic P content increases while P fixation reduces in all soils due to biochar treatment with increase in DAI. The Total-P and Organic-P fraction also increases for all the four samples due to addition of biochar. Hence, it is concluded that biochar is beneficial for soils in increasing P-availability while the combination of Biochar with Microbes (Bacteria and Fungi) acts as a better combination for enhancing all nutrients and various P fractions in both the type of soils (acidic and alkaline). (B.P. Dhyani) (Akansha Singh) Advisor AuthorEnglishThesis