Globally, many developing countries are facing silent epidemics of nutritional deficiencies in human beings and animals. The lack of diversity in diet, i.e., cereal-based crops deficient in mineral nutrients is an additional threat to nutritional quality. The present review accounts for the significance of biofortification as a process to enhance the productivity of crops and also an agricultural solution to address the issues of nutritional security. In this endeavor, different innovative and specific biofortification approaches have been discussed for nutrient enrichment of field crops including cereals, pulses, oilseeds and fodder crops. The agronomic approach increases the micronutrient density in crops with soil and foliar application of fertilizers including amendments. The biofortification through conventional breeding approach includes the selection of efficient genotypes, practicing crossing of plants with desirable nutritional traits without sacrificing agricultural and economic productivity. However, the transgenic/biotechnological approach involves the synthesis of transgenes for micronutrient re-translocation between tissues to enhance their bioavailability. Soil microorganisms enhance nutrient content in the rhizosphere through diverse mechanisms such as synthesis, mobilization, transformations and siderophore production which accumulate more minerals in plants. Different sources of micronutrients viz. mineral solutions, chelates and nanoparticles play a pivotal role in the process of biofortification as it regulates the absorption rates and mechanisms in plants. Apart from the quality parameters, biofortification also improved the crop yield to alleviate hidden hunger thus proving to be a sustainable and cost-effective approach. Thus, this review article conveys a message for researchers about the adequate potential of biofortification to increase crop productivity and nourish the crop with additional nutrient content to provide food security and nutritional quality to humans and livestock.

Seaweed extract biostimulants are among the best modern sustainable biological plant growth promoters. They have been proven to eliminate plant diseases and abiotic stresses, leading to maximizing yields. Additionally, they have been listed as environmentally friendly biofertilizers. The focus of the present research is the use of a commercial seaweed biostimulant as an eco-friendly product (formally named True Algae Max (TAM). During the 2017 and 2018 seasons, five treatments of various NPK:TAM ratios were applied via regular fertigation, namely a conventional treatment of 100% NPK (C₀) alongside combinations of 25%, 50%, 75%, and 100% (C₂₅, C₅₀, C₇₅, and C₁₀₀) of TAM, to evaluate the effectiveness of its bioactive compounds on enhancing growth, yield, and NPK content of cucumber (Cucumis sativus) under greenhouse conditions. TAM is rich in phytochemical compounds, such as milbemycin oxime, rhodopin, nonadecane, and 5-silaspiro [4.4]nona-1,3,6,8-tetraene,3,8-bis(diethylboryl)-2,7-diethyl-1,4,6,9-tetraphenyl-. Promising measured parameter outcomes showed the potentiality of applying TAM with and without mixes of ordinary NPK application. TAM could increase cucumber yield due to improving chemical and physical features related to immunity, productivity, and stress defense. In conclusion, it is better to avoid applying mineral fertilizers, considering also that the organic agricultural and welfare sectors could shortly depend on such biotechnological tools and use them to fulfill global food demands for improved sustainability.

Bioactive molecules derived from seaweed extracts are revolutionary bio-stimulants used to enhance plant growth and increase yield production. This study evaluated the effectiveness of a commercially available seaweed liquid extract, namely, True-Algae-Max (TAM^®), as a plant growth stimulant on nutritional, and antioxidant activity of Capsicum annuum. Three concentrations of TAM^® (0.25, 0.5, and 1%) of various NPK: TAM^® ratios were investigated via foliar spray, over 2017 and 2018 cultivation seasons, under greenhouse conditions. TAM^® is rich in phytochemical compounds, such as ascorbic acid (1.66 mg g⁻¹), phenolics (101.67 mg g⁻¹), and flavonoids (2.60 mg g⁻¹) that showed good antioxidant activity (54.52 mg g⁻¹) and DPPH inhibition of 70.33%. Promoting measured parameter results stated the extensive potentiality of TAM^® application, in comparison with conventional NPK treatment. Yield and composition of C. annuum were significantly improved in all TAM^® treated groups, especially the TAM_0.5% concentration, which resulted in maximum yield (4.23 Kg m⁻²) and significant amounts of profuse biological molecules like chlorophyll, ascorbic, phenolic compounds, flavonoids, and total nutrients. Compared to the NPK control treatments, C. annuum treated with TAM_0.5% improved the total antioxidant activity of hot Pepper from 162.16 to 190.95 mg g⁻¹. These findings indicate that the extract of seaweed can be used as an environmentally friendly, multi-functional biostimulant in the agricultural field for more sustainable production, in addition to reducing the use of hazardous synthetic fertilizers.

Herein, we report the synthesis of eight new mononuclear and binuclear Co²⁺, Ni²⁺, Cu²⁺, and Zn²⁺ methoxy thiosemicarbazone (MTSC) complexes aiming at obtaining thiosemicarbazone complex with potent biological activity. The structure of the MTSC ligand and its metal complexes was fully characterized by elemental analysis, spectroscopic techniques (NMR, FTIR, UV-Vis), molar conductivity, thermogravimetric analysis (TG), and thermal differential analysis (DrTGA). The spectral and analytical data revealed that the obtained thiosemicarbazone-metal complexes have octahedral geometry around the metal center, except for the Zn²⁺-thiosemicarbazone complexes, which showed a tetrahedral geometry. The antibacterial and antifungal activities of the MTSC ligand and its (Co²⁺, Ni²⁺, Cu²⁺, and Zn²⁺) metal complexes were also investigated. Interestingly, the antibacterial activity of MTSC- metal complexes against examined bacteria was higher than that of the MTSC alone, which indicates that metal complexation improved the antibacterial activity of the parent ligand. Among different metal complexes, the MTSC- mono- and binuclear Cu²⁺ complexes showed significant antibacterial activity against Bacillus subtilis and Proteus vulgaris, better than that of the standard gentamycin drug. The in silico molecular docking study has revealed that the MTSC ligand could be a potential inhibitor for the oxidoreductase protein.

A field investigation on direct seeded rice (DSR) was carried out in the two consecutive rice growing seasons of 2017 and 2018 at Pantnagar, Uttarakhand, India for the development and validation of soil test crop response (STCR) to fertilizer and for assessing the performance of STCR-treatments as compared to the general recommended dose (GRD) in terms of yield, nutrient uptake and use efficiency, and the economics of DSR. For producing 1 Mg of rice-grain, the required nutrients (N, P, and K) were 2.01 kg, 0.44 kg, and 3.06 kg; the contribution from the soil was 22.05%, 37.34%, and 41.48%; from applied farmyard manure 23.25%, 28.34%, and 16.80%, from fertilizer 38.08%, 49.93%, and 252.98%; and from fertilizer with FYM 44.83%, 60.57%, and 278.70%; for N, P, and K, respectively. The STCR approach, with or without FYM, at both the target yields (4.5 Mg ha⁻¹ and 5.0 Mg ha⁻¹) markedly enhanced the grain yield (20.2% to 32.3%) and production efficiency over the GRD. It also exhibited a higher NPK uptake and use efficiency, along with better profitability, than the GRD. Therefore, the STCR-targeted yield approach could improve the yield, economics, and efficiency of nutrient use for direct seeded rice.

Enhancing nutrient use efficiencies (NUEs) is an important factor in achieving the long-term sustainability of a production system. Our two-year experiment was aimed at accessing the NUEs of the integration of macro- and micronutrient fertilization responses of three lentil (Lens culinaris) cultivars. Three cultivars were planted in the main plots, and ten nutrient combinations were used in the sub-plots: N1, control; N2, 100% recommended dose of fertilizers (RDF) (20:40—N:P₂O₅); N3, vermicompost (VC) at 2 t ha⁻¹; N4, 50% recommended dose of nitrogen (RDN) + 100% recommended dose of phosphorus (RDP) + VC at 1 t ha⁻¹; N5, RDF + 0.5% ZnSO₄; N6, RDF + 0.5% FeSO₄; N7, RDF + 0.5% ZnSO₄ + 0.5% FeSO₄; N8, 50% RDN + 100% RDP + VC at 1 t ha⁻¹ + 0.5% ZnSO₄; N9, 50% RDN + 100% RDP + VC at 1 t ha⁻¹ + 0.5% FeSO₄; and N10, 50% RDN + 100% RDP + VC at 1 t ha⁻¹ + 0.5% ZnSO₄ + 0.5% FeSO₄. The results show that the cultivar HM-1 (1.59–1.61 Mg ha⁻¹) recorded a significantly higher seed yield than cultivars Sapna (1.31–1.33 Mg ha⁻¹) and Garima (both 1.30 Mg ha⁻¹), while the cultivar Sapna had significantly more stover yield (1.86–1.90 Mg ha⁻¹) than cultivar HM-1 (1.68–1.73 Mg ha⁻¹). Cultivar HM-1 was more efficient in terms of partial factor productivity for N (77.5–78.5 kg kg⁻¹), P (48.2–48.7 kg kg⁻¹), K (143.6–145.5 kg kg⁻¹), Zn (1336–1352 kg kg⁻¹), and Fe (417–421 kg kg⁻¹) than Sapna and Garima. Application of 50% N + 100% P + VC at 1.0 t ha⁻¹ + 0.5% ZnSO₄ + 0.5% FeSO₄ resulted in higher seed yield (1.63–1.65 Mg ha⁻¹) and agronomic efficiency for N (26.3–28.8 kg kg⁻¹), P (12.42–13.63 kg kg⁻¹), and K (52.3–57.4 kg kg⁻¹) over other tested practices in both years. Hence, it could be concluded that considering the integrated nutrient management paradigm including 10 kg N ha⁻¹ coupled with 40 kg P₂O₅ ha⁻¹ through synthetic fertilizers, vermicomposting 1.0 t ha⁻¹ as an organic source and foliar spray of 0.5% each of ZnSO₄ and FeSO₄ (N10) produced a 56.8% higher seed yield than the control, in addition to improving nutrient dynamics and NUEs for N, P, K, Zn, and Fe. Therefore, integrated fertilization coupled with cultivar selection could help to achieve the long-term food and nutritional sustainability targeted by the Sustainable Development Goals (SDGs).