INTRODUCTION Globally, total area under organic certification process (registered under National Programme for Organic Production) is 3.56 m.ha (2017-18). This includes 1.78 million ha (50%) cultivable area and another 1.78 m.ha (50%) for wild harvest collection (APEDA, 2018). Among all the states, Madhya Pradesh has covered largest area under organic certification followed by Rajasthan, Maharashtra and Uttar Pradesh. India produced around 1.70 million MT (2017-18) of certified organic products which includes all varieties of food products namely Oilseeds, Sugarcane, Cereals & Millets, Cotton, Pulses, Medicinal Plants, Tea, Fruits, Spices, Dry Fruits, Vegetables, Coffee etc. The production is not limited to the edible sector but also produces organic cotton fiber, functional food products etc. In terms of export value realization, Oilseeds (47.6%) lead among the products followed by Cereals and millets (10.4%), Plantation crop products such as Tea and Coffee (8.96%), Dry fruits (8.88%), Spices and condiments (7.76%) and others (APEDA, 2018). Sesame is produced over an area of 8.8 million hectares with an annual production of around 2.8 million tonnes with average productivity of 382 kg ha-1 in the world. India is the leading country with higher (25.8%) share of production from the largest (29.8%) share of area and highest export (40%) in the world. In India, sesame is grown over an area of 16.66 lakh hectares with production of 1.74 lakh tonnes and productivity of 448 kg ha-1. In Telangana, it is grown over an area of 21,000 hectares with an annual production of 15,000 tonnes and productivity of 714 kg ha-1. It is mainly grown in the districts of Northern Telangana, viz., Adilabad, Jagtial, Karimnagar and Nizamabad, as kharif crop and also as summer crop after rice, turmeric and cotton during Kharif/Rabi season (INDIASTAT, 2017). Sesamum oil consisted 85% unsaturated fatty acid is highly stable and has reducing effect on cholesterol and prevent coronary heart diseases. Sesame is called as ‘queen of oils’ because of extra ordinary cosmetic, skin care qualities and as well as resistance to rancidity. It is grown in all seasons of the year and being a short duration crop, fit well into various cropping sequences/systems and most preferred by farmers because of low input requirement with higher output. Sesame has emerged as a valuable export crop earning more than Rs.1000 crores from the export of 2.5 lakh tonnes of sesame seed since it is mostly used in foods and medicine in developed countries. Of late, pesticide residues are becoming major problem in the promotion of sesame exports. Use of excess chemical fertilizers had resulted in increased crop yields in the initial year which was the result of green revolution but it had adversely affected the sustainability at the present and future generations. Therefore, organically produced sesame will suit to tailor made requirements of buyers and will get premium price in both national and international markets (Gopinath et al., 2011). The primary goal of organic agriculture is to optimize the inputs and productivity of interdependent communities of soil life, plants, animals and people. The management of nutrients in organic farming system presents a formidable challenge as the use of inorganic fertilizers is not permitted (Muthuswamy et al., 1990). Currently agriculture is heavily dependent on mineral fertilizers and inorganic pesticides, and impacts of the continuous application are reflected in deteriorating soil health and increased resistance to pest and pathogens (Kumar et al., 2010; Cai et al., 2016). Biofertilizers are considered as low monetary inputs and play a vital role in agricultural ecosystem as the microorganisms fix atmospheric nitrogen, convert fixed phosphorous potassium into available forms. Therefore, organic inputs need to be optimised to ensure optimum and regulated nutrient supply which will guarantee optimum crop yields with minimum losses of nutrients and ensure sustainable environment. Hence, an experiment was conducted to optimize organic nutrient management practices in sesame under rainfed conditions. MATERIAL AND METHODS The experiment was carried out at College Farm, Agricultural College, Polasa, Jagtial, Professor Jayashankar Telangana State Agricultural University. The farm is geographically situated at an altitude of 243.4 m above mean sea level on 18º4940N latitude and 78º5645E longitude and it is categorized under Northern Zone of Telangana State. The weekly mean maximum temperature during crop growth period was ranged from 29.2°C to 32.3°C during 2019 with an average of 31.2°C, while the weekly mean minimum temperature ranged from 15.6°C to 24.1°C with an average of 21.1°C. The total rainfall received during crop growth period was 465.1mm and total rainy days of 37. Rainfall was not received during 45th, 46th, 47th, 48th and 49th standard weeks while maximum rainfall (104.5 mm) was received during 39th standard week. An average of 6.4 hours day-1 sunshine hours was received. Soil samples were collected randomly at a depth of 0-30 cm from the experimental site initially before sowing and finally after harvest. The composite samples were then analysed for their physico-chemical characteristics (pH, EC, OC), available N, P and K. The experiment was initiated with four main treatments (T1: 50 % N through FYM + 25 % N through Vermicompost + 25 % N through Neem cake, T2: 50 % N through FYM + 25 % N through Vermicompost enriched with rock phosphate + Microbial consortia @ 2 kg ha-1, T3: 50 % N through FYM + 25 % N through Neem cake + Humic acid granules @ 12.5 kg ha-1, T4: 75 % N through FYM + 25 % N through Vermicompost enriched with rock phosphate + Microbial consortia @ 2 kg ha-1) and four sub treatments (foliar application of S1: Panchagavya @ 3 %, S2: NSKE @ 3 %, S3: Vermiwash @ 10 ml lit-1, S4: Humic acid @ 1ml lit-1) with three replications. FYM was applied as basal, Vermicompost and enriched Vermicompost were applied as top dressing at 25 DAS and 50 DAS. Humic acid granules, neem cake and microbial consortia were applied as basal. The recommended dose of fertilizers for the rainfed sesamum was 60 kg N, 20 kg P2O5 and 40 kg K2O ha-1. Out of this, 30 kg N, 20 kg P2O5 and 20 kg K2O were applied as basal. 30 kg N and 20 kg K2O were applied after 30 days. The P and K contribution from organic sources was worked out and the remaining P and K was applied through straight fertilizers. Chemical analysis of FYM, Vermicompost, neem cake and Vermicompost enriched with rock phosphate was carried as per Bradstreet, 1965. The N, P and K content was 0.51, 0.17 & 0.43 % in FYM; 1.16, 0.21&0.62 % in vermicompost; 4.31, 0.63 & 1.26 % in neem cake and 1.21, 1.50 & 0.67 % in vermicompost enriched with rock phosphate respectively. Microbial consortia @ 2 kg ha-1 was applied as basal in T2 and T4 treatments. It is a combination of N biofertilizers (azotobacter), P solubilising bacteria (PSB), K solubilising bacteria (KRB) and Zinc solubilising bacteria. Humic acid granules @ 12.5 kg ha-1 with 6% humic acid, 12% isolated amino acid, 4% fulvic acid 4% other nutrients was applied as basal in T3 treatment. Three sprays of organic nutrients (sub plots) were initiated at flower initiation and continued with one week interval @ 45, 52, 59 DAS. Sesame variety JCS 1020 released from Regional Agricultural Research Station, Jagtial, Telangana state during the year 2019. It is a non-branched variety with multi capsular character and suitable for dense sowing or higher population. Its yield in late kharif is 800 kg ha-1 and in summer is 1050-1100 kg ha-1. Crop duration is 100 days. Its oil content is 46-49%. It is a multi capsular white seeded variety and resistant to powdery mildew disease. The gross plot size was 5.1 × 5 m2 and a net plot size of 3.9 × 4.4 m2. Seed rate of 2.5 kg acre-1 is required with a spacing of 30 cm × Solid rows and sown directly. Gap filling was taken up after 10 days of direct sowing in the field. Thinning of excess seedlings was done at 20 days after sowing. No herbicides were used as the experiment is maintained organically in the field. Weeds were removed by manual weeding carried at 25 and 45 DAS in the field. Application of Bacillus thuringenesis @ 2 g lit-1 in the field to control lepidopteran pests and majorly leaf webbers at flowering stage was followed. Drenching with Trichoderma viridae @ 5 g lit-1 in the field to control sucking pests, cercospora leaf spot and alternaria leaf spot applied at 60 DAS. As the crop was grown under rainfed conditions, irrigation was not provided till flowering stage. Two Irrigations were provided at pod filling stage as there was no rainfall after standard week 44 (November) 60 and 75 DAS. The crop was harvested on 5th December 2019. RESULTS AND DISCUSSION The influence of organic nutrient management practices on microbial count of bacteria of in soil at different stages of crop growth: There was no significant difference among main treatments on microbial count of bacteria (105 CFU g-1 soil) at 25 & 50 DAS. At later stages, the effect of main treatment T2: 50 % N through FYM + 25 % N through vermicompost enriched with rock phosphate + microbial consortia @ 2 kg ha-1 (218.4) recorded significantly higher microbial count of bacteria and was on par with T4: 75 % N through FYM + 25 % N through vermicompost enriched with rock phosphate + microbial consortia @ 2 kg ha-1 (216.0). It was also at par with T1: 50 % N through FYM + 25 % N through vermicompost + 25 % N through Neem cake (204.8) at 75 DAS and was followed by T3: 50 % N through FYM + 25 % N through Neem cake + Humic acid granules @ 12.5 kg ha-1 at 75 DAS (192.8). At harvest, it was observed that significantly highest microbial count of bacteria was found with T4: 75 % N through FYM + 25 % N through vermicompost enriched with rock phosphate + microbial consortia @ 2 kg ha-1 (179.8) and was on par with T3: 50 % N through FYM + 25 % N through Neem cake + Humic acid granules @ 12.5 kg ha-1 (172.8) and T2: 50 % N through FYM + 25 % N through vermicompost enriched with rock phosphate + microbial consortia @ 2 kg ha-1 (165.7). Lowest microbial activity was observed with T1: 50 % N through FYM + 25 % N through vermicompost + 25 % N through Neem cake (157.9). The increase in microbial activity in organic farming system was documented by Nardi et al. (2009) and Swaminathan et al. (2007). There was no significant difference among sub treatments on microbial count of bacteria at all growth stages. The interaction effect between main treatments and sub treatments on microbial count of bacteria (105 CFU g-1soil) at 25 DAS, 50 DAS, 75 DAS and at harvest in plant and seed was found non significant. The influence of organic nutrient management practices on microbial count (105 CFU g-1 soil) of fungi of sesame: There was no significant difference among main treatments on microbial count of fungi (105 CFU g-1 soil) at 50 DAS, 75 DAS & at harvest. Lower number was observed with T2: 50 % N through FYM + 25 % N through vermicompost enriched with rock phosphate + microbial consortia @ 2 kg ha-1 (15.8). At 25 DAS, T1: 50 % N through FYM + 25 % N through vermicompost + 25 % N through Neem cake (19.7) recorded highest microbial count of fungi and on par with T4: 75 % N through FYM + 25 % N through vermicompost enriched with rock phosphate + microbial consortia @ 2 kg ha-1 (18.9), T3: 50 % N through FYM + 25 % N through Neem cake + Humic acid granules @ 12.5 kg ha-1 (18.7) and was followed by T2: 50 % N through FYM + 25 % N through vermicompost enriched with rock phosphate + microbial consortia @ 2 kg ha-1 (17.7). The microbial consortia may have increased fungal (beneficial) colonies by increasing the nutrient availability and rhizosphere development (Jarvan et al., 2014). It is observed that there was no significant difference among sub treatments on microbial count of fungi at all growth stages. The interaction effect between main treatments and sub treatments on microbial count of fungi (105 CFU g-1 soil) at 25 DAS, 50 DAS, 75 DAS and at harvest in plant and seed was found no significant. Effect of organic nutrient management practices on dehydrogenase activity (µg TPF g of soil-1day-1) in soil: Dehydrogenase activity (DHA) is one of the important and most sensitive bioindicator relating to soil fertility. It serves as an indicator of the microbiological redox systems and could be considered as a good and adequate measure of microbial oxidative activities in soil (Jarvan et al., 2014). Influence of organic nutrient management practices on dehydrogenase activity (µg TPF g of soil-1 day-1) in soil during the experiment was presented in Table 1. The dehydrogenase activity was significantly influenced by main and sub treatments at all stages of crop growth. Dehydrogenase activity was reached its peak at 50 DAS and slowly decreased at 75 DAS and at harvest. Dehydrogenease activity was significantly higher with T4: 75 % N through FYM + 25 % N through vermicompost enriched with rock phosphate + microbial consortia @ 2 kg ha-1 at 25 DAS (14.4), 50 DAS (24.41), 75 DAS (20.21) and at harvest (17.74) compared with other treatments. It was followed by T2: 50 % N through FYM + 25 % N through vermicompost enriched with rock phosphate + microbial consortia @ 2 kg ha-1, T1: 50 % N through FYM + 25 % N through vermicompost + 25 % N through Neem cake and T3: 50 % N through FYM + 25 % N through Neem cake + Humic acid granules @ 12.5 kg ha-1 respectively, at all stages of crop growth. It was supported by Jarvan et al. (2014) who stated that organically managed crop rotation increased dehydrogenase activity in soil. Dehydrogenase reflects the total range of oxidative activity of soil microflora (Liang et al. 2014). Foliar application of organic nutrients also significantly increased Dehydrogenase activity in soil. Foliar application of Panchagavya @ 3 % showed higher dehydrogenase activity (14.03, 23.85, 19.44 and 17.32) at 25, 50, 75 DAS and at harvest. It was followed by and S4: Humic acid @ 1ml lit-1, S3: Vermiwash @ 10ml lit-1 and S2: NSKE @ 3 %. It was supported by Ramakrishna et al. (2017). Interaction between main treatments and foliar application of organic nutrients (sub treatment) was insignificant on dehydrogenase activity of soil at different stages of crop growth in sesamum. The influence of organic nutrient management practices on Available N, P2O5, K2O status (kg ha-1) and Organic carbon content (%) in soil: Influence of organic nutrient management practices on available N, P2O5, K2O status and Organic carbon content in soil after harvest of sesame was presented in Table 2. The available N, P2O5, K2O status and Organic carbon content in soil after harvest of sesame was found to be significantly influenced by main treatments. The treatment T4: 75 % N through FYM + 25 % N through vermicompost enriched with rock phosphate + microbial consortia @ 2 kg ha-1 has significantly highest available N, P2O5, K2O status and Organic carbon content in soil (245.4, 38.4, 317.8 kg ha-1 and 0.5%). Lower available N, P2O5, K2O status and Organic carbon content in soil after harvest of sesame was observed with T3: 50 % N through FYM + 25 % N through Neem cake + Humic acid granules @ 12.5 kg ha-1 (217.5, 31.1, 276.3 kg ha-1 and 0.4%). Available N, P2O5, K2O and organic carbon in soil was improved under integrated application of chemical, organic and biological sources of nutrients compared to its initial soil fertility. It could be attributed to addition of root biomass, fallen leaves of sesame and black gram and organic matter through FYM or Vermicompost (Vishal Kumar et al., 2019). Mokariya et al. (2021) states that most of growth and yield attributes contributed in seed yield of sesame evidently resulted in higher yield in treatments which get nitrogen and phosphorus through chemical fertilizers. There was no significant difference among foliar application of organic nutrients in available N status in soil after harvest of sesame but found significant with available P2O5 and K2O status and Organic carbon content in soil. Higher available P2O5 and K2O status and Organic carbon content in soil after harvest of sesame of 35.7, 311.7 kg ha-1 and 0.5% was observed with foliar application of Humic acid @ 1ml lit-1 and was at par with Panchagavya @ 3% and (36.0, 301.9 kg ha-1 and 0.5%). Lower available P2O5 and K2O status and Organic carbon content in soil after harvest of sesame was observed with foliar application of NSKE @ 3 % (32.6, 270.5 kg ha-1 and 0.4%). The interaction effect between main treatments and sub treatments on available N, P2O5, K2O status and Organic carbon content in soil after harvest of sesame was found non significant. The influence of organic nutrient management practices on seed yield (kg ha-1) of sesame: Main organic nutrient management practices and their interaction with foliar application of organic nutrients (sub treatments) showed significant effect on seed yield of sesame. But, only foliar application of organic nutrient (sub treatments) showed non significant effect on seed yield of sesame. The effect of main treatments on seed yield of sesame was found significant. Application of 75 % N through FYM + 25 % N through Vermicompost enriched with rock phosphate + Microbial consortia @ 2 kg ha-1 (T4) produced significantly higher seed yield (478.6 kg ha-1) and was superior over other treatments. It may be due to balanced and timely supply of nutrients from diversified sources of nutrients (FYM, vermicompost, microbial consortia) that resulted in prolonged availability of nutrients to crop (Dharati et al., 2017). The positive influence of INM on nutrient content of crop due to improved nutritional environment both in the rhizosphere and the plant system (Nirav Parmar et al., 2020). This was closely followed by application of T2: 50 % N through FYM + 25 % N through Vermicompost enriched with rock phosphate + Microbial consortia @ 2 kg ha-1 in recording higher sesame seed yield (433 kg ha-1) and was at par with T1: 50 % N through FYM + 25 % N through Vermicompost + 25 % N through Neem cake (424) and T3: 50 % N through FYM + 25 % N through Neem cake + Humic acid granules @ 12.5 kg ha-1 (405). Vermicompost enriched with rock phosphate was found to be effective compared to only vermicompost application due to increased availability of P, K and S to oilseed crops that increased seed yield and quality of sesame (Parthasarathi and Ashwin Chandra, 2012). Mokariya et al. (2021) revealed that proper fertilization with increased net photosynthesis and greater mobilization of photosynthates towards reproductive structures, which might increased the yield attributes and finally the seed and stalk yield of sesame. Among sub treatments, foliar application of different organic sources i.e., Panchagavya, Neem Seed Kernel Extract, vermiwash and humic acid as foliar application effectively increased seed yield of sesame though found non-significant among them. In addition to small fraction of nutrients, the above organic sources has enzymatic and hormonal action that resulted in increase in seed yield besides improving the quality of sesame and lower incidence of pest and diseases. Application of panchagavya @ 3 % produced higher sesame yield (450 kg ha-1) and was closely followed by humic acid, Vermiwash and Neem Seed Kernel Extract respectively. Interaction between main treatments and sub treatments was significant on seed yield of Sesame and was presented along with stalk yield of Sesame.