Srivastava, Rajeev KumarBARALA, VIJESH KUMAR2024-06-212024-06-212023M/AGRO/306/2021–22https://krishikosh.egranth.ac.in/handle/1/5810210739The research-work was conducted in the kharif and rabi season of 2022- 23 at Research-Farm RPCAU-Pusa, Bihar to study the “Effect of Brown Manuring along with varying combination of Fe, Zn and Nano Urea on Direct Seeded Rice (DSR) under Rice–Wheat Cropping System”. The experimental soil was a sandy-loam and had a low SOC (0.40%), low availability of N (211 kg ha-1) and K (110 kg ha-1), medium availability of P (11.0 kg ha-1), and pH was found in alkaline range i.e., 8.81. The major three objectives of current research work viz., to study the effect of Brown manuring along with varying combination of Fe, Zn and nano urea on growth and yield of DSR and its residual effect on Wheat under Rice-Wheat cropping system; to evaluate the performance of Brown manuring along with varying combination of Fe, Zn and Nano urea on physiological parameters and nutrient uptake of DSR under Rice-Wheat cropping system; to work out the economics. The current field study was done on Rice (DSR)-wheat cropping system with eight varying nutrient management strategies, which being administered in rice component crop only (variety: Rajendra Bhagwati) and data was also recorded for wheat (variety, DBW-252) besides rice in order to find the residual effect of different treatment in rice on succeeding component crop (wheat) to observe residual effect. The treatment details are mentioned here T1: 100% Recommended Dose of Nitrogen (RDN), T2: 100% RDN + Brown Manuring (BM), T3: 50% RDN + two foliar application of Nano Urea @ 0.4% at 25 & 55 DAS (Days After Sowing), T4: 50% RDN + two foliar application of Nano Urea @0.4% at 25 & 55 DAS + one foliar spray of FeSO4 @1% + ZnSO4 @0.5%, T5: 50% RDN + two spray of FeSO4 @1% & ZnSO4 @0.5%, T6: 50% RDN + BM + two foliar application of Nano Urea @0.4 % at 25 & 55 DAS, T7: 50% RDN+ BM + two foliar application of Nano Urea @0.4 % at 25 & 55 DAS + one foliar spray of FeSO4 @1% + ZnSO4 @0.5%, T8: 50% RDN + BM +two spray of FeSO4 @ 1% & ZnSO4 @ 0.5%. Whatever data generated for rice and wheat component crops were analysed by suitable statistical design i.e., Randomised Block Design (RBD) and experimental variables under study was randomised in replication block as well as replicated thrice. Recommended Dose of P and K was applied invariably in all different treatments. The one-year investigation revealed that application of 50% RDN+ BM + two foliar application of Nano Urea @0.4% at 25 & 55 DAS + one foliar spray of FeSO4 @1% + ZnSO4 @0.5% (T7) was found best in respect to almost all growth and yield attributing characters including plant height (cm), dry matter accumulation (g m-2), crop growth rate (g m-2 d-1), tiller numbers m-2, leaf count m-2, biomass partitioning (leaf, culm and panicle hill-1 g-1), canopy cover etc., as well as yield attributes (no. of panicle m-2, panicle length in cm and no. of grains panicle-1) & yields of rice and this treatment was found significantly better than 50% RDN + two foliar application of Nano Urea @ 0.4% at 25 & 55 DAS (T4) and over the rest treatments also. It means application of nano-urea along with the Fe, Zn and BM resulted in markedly higher growth and yield comparing to RDN only in the direct seeded rice. In following wheat crop, the significant effect of brown manuring being administered in rice crop (previous crop) had been observed, which showed residual effect BM applied in rice crop on succeeding crop wheat. The best growth and yield results including plant height (cm), DMA (Dry Matter Accumulation - gm-2), tiller numbers m-2, leaf count m-2, yield attributes (no. of spike m-2, spike length-cm, no. of spikelet spike-1 and no. of grains spike-1) and yields (grain and straw) of rice was found in T7 that involved the application of 50% RDN+ BM + two foliar application of Nano Urea @0.4 % at 25 & 55 DAS + one foliar spray of FeSO4 @1% + ZnSO4 @0.5% and this treatment was statistically at par with the other three treatments that had good crop growth in the previous crop and had brown manure. Regarding nutrient content in plants, it was found that application nano-N considerably changed the N content (%) of rice's grain and straw. However, there were no any significant differences between plants' P and K contents. T7 shows maximum content of N (nitrogen-%) and this was significantly higher than T4. After harvest of rice, from the soil nutrient (fertility) point of view, the OC (organic carbon) and nitrogen were found markedly higher in T7, T8, T2 and T6 as these all treatments had brown manuring. Maximum OC and N were found by the application of 50% RDN+ BM + two foliar application of Nano Urea @0.4 % at 25 & 55 DAS + one foliar spray of FeSO4 @1% + ZnSO4 @0.5%, which was markedly higher as compared to 100% RDN (T1) and other non-BM treatments. Under rice (DSR)-wheat cropping system approach, it was noted that the application of 50% RDN+ BM + two foliar application of nano urea @0.4 % at 25 & 55 DAS + one foliar spray of FeSO4 @1% + ZnSO4 @0.5% (T7¬) resulted in the maximum values of gross returns (Rs. 263099 ha-1), net returns (Rs. 177093 ha-1) and B:C ratio (2.06). It can be inferred from this investigation that the application of 50% RDN+ BM + two foliar application of Nano Urea @0.4 % at 25 & 55 DAS + one foliar spray of FeSO4 @1% + ZnSO4 @0.5% resulted maximum growth, yield, and economics of the rice cultivation, and the residual efficacy of brown manuring and the application of RDF dose in wheat gave maximum growth and yield. Finally, the overall economics of the system was lucidly increased and showed its marked economic viability.EnglishThesis