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Foliar fertilization has great potential to give higher yields under intensive cropping system and in enhancing the crop tolerance to drought conditions. Different responses of yield to foliar fertilization are probably associated with incorrect timing of application, use of inappropriate fertilizer and lack of concern of soil available nutrients and environmental conditions. Though soil application of nutrients cannot be replaced totally with foliar fertilization, but under various situations like rainfed condition, foliar nutrition can play very important role in enhancing crop yield and nutrient use efficiency. Focusing on this, a field experiment was conducted in the Agricultural Research Station, Kovilpatti, under rainfed situation from 2017 to '20 to evaluate the response of foliar application of plant nutrients sprayed during moisture stress condition and to improve the growth and yield of sorghum under rainfed condition. This experiment was laid out in split plot design with replicated thrice and the treatments consisted of main plots: M1 – foliar spray during dry spell, M2 – foliar spray after relieving of stress/dry spell (with favorable soil moisture) and subplots: S1 – urea@1%, S2 – urea@2%, S3 – water soluble complex fertilizer (19:19:19)@0.5%, S4 – water soluble complex fertilizer (19:19:19)@0.5% + recommended dose of micronutrient for foliar spray (to be decided based on soil test: zinc, boron, iron, manganese, etc.), S5 – ZnSO4@0.5%, S6 – water spray, S7 – control (no spray of any material/water) under rainfed vertisols of semiarid region. The obtained results showed that the application of water soluble complex fertilizer (19:19:19)@0.5% sprayed during the dry spell significantly increased the plant height, earhead length and grain test weight. This attributes resulted in higher grain yield (1448 kg ha−1), stover yield (2288 kg ha−1), net returns (Rs. 8748 ha−1), B:C (1.16) and rainwater use efficiency (3.85 kg ha−1-mm) when compared to other practices in rainfed sorghum. There is a gradual increase in total major plant nutrient uptake, viz. nitrogen (22.3 kg ha−1), phosphorus (4.56 kg ha−1) and potassium uptake (26.0 kg ha−1) with the foliar application of water soluble complex fertilizer (19:19:19)@0.5% applied during the dry spell condition (S3) during drought stress condition (M1). Foliar application of nutrients along with soil application has several advantages in supplementing the nutritional requirements of crops such as rapid and efficient response by the plants, less product needed and independence of soil conditions. Foliar nutrition designed to eliminate the problems like fixation and immobilization of nutrients. Hence, foliar nutrition is recognized as an important method of fertilization during the dry spell under rainfed condition in modern agriculture. [ABSTRACT FROM AUTHOR]

Carbon-free nickel alloy maraging steel has high demand in manufacturing aerospace vehicles and hypersonic missiles. Due to the absence of carbon and the strengthening of intermetallic precipitates, maraging steel can attain high strength and toughness with ductility. This material has enormous weldability in both annealed and post-weld heat-treated (PWHT) conditions. During high-thickness sections, the heat flow rate and the number of passes were found to be redundant. The existence of reverted austenite (RA) has been identified because prolonged aging also has an impact on the mechanical characteristics of the weldment. The present research demonstrates the characterization of plasma arc welded (PAW) maraging steel MDN 250 in welded and PWHT conditions. The weldments were subjected to three types of heat treatment, namely, (i) Subsequent Aging (TA), (ii) Solution treating + Subsequent Aging (STA), and (iii) Homogenizing + Solution treating + Subsequent Aging (HTA). This study also emphasizes the importance of precipitates and RA in affecting the strength and toughness of welded joints. The HTA treatment solely helps to eliminate the RA from the weldment. The microstructural study depicts the formation of reverted austenite in the TA condition. The reverted austenite has not been found in the microstructure under HTA conditions. The EBSD (Electron backscatter diffraction) analysis has resulted that the RA has been eliminated. The EDS (Electron Dispersive Spectroscopy) analysis shows that segregation of the enriched alloys has been effectively lowered in HTA condition. Compared to the other weldments' mechanical characterization, the HTA condition gives supremacy results. The average ultimate tensile strength of 1830 MPa has been achieved in HTA condition, with a yield strength of 1809 MPa. The average fracture toughness results of 88.3 MPa√ m was obtained in HTA condition. The work display of PAW (Plasma Arc Welding) is capable of meeting all of the requirements for welding maraging steel in high-thickness sections. [ABSTRACT FROM AUTHOR]