Phyto-melatonin improves crop yield by mitigating the negative effects of abiotic stresses on plant growth. Numerous studies are currently being conducted to investigate the significant performance of melatonin in crops in regulating agricultural growth and productivity. However, a comprehensive review of the pivotal performance of phyto-melatonin in regulating plant morpho-physiological and biochemical activities under abiotic stresses needs to be clarified. This review focused on the research on morpho-physiological activities, plant growth regulation, redox status, and signal transduction in plants under abiotic stresses. Furthermore, it also highlighted the role of phyto-melatonin in plant defense systems and as biostimulants under abiotic stress conditions. The study revealed that phyto-melatonin enhances some leaf senescence proteins, and that protein further interacts with the plant’s photosynthesis activity, macromolecules, and changes in redox and response to abiotic stress. Our goal is to thoroughly evaluate phyto-melatonin performance under abiotic stress, which will help us better understand the mechanism by which phyto-melatonin regulates crop growth and yield.

Rice is one of the staple foods for the majority of the global population that depends directly or indirectly on it. The yield of this important crop is constantly challenged by various biotic stresses. Rice blast, caused by Magnaporthe oryzae (M. oryzae), is a devastating rice disease causing severe yield losses annually and threatening rice production globally. The development of a resistant variety is one of the most effective and economical approaches to control rice blast. Researchers in the past few decades have witnessed the characterization of several qualitative resistance (R) and quantitative resistance (qR) genes to blast disease as well as several avirulence (Avr) genes from the pathogen. These provide great help for either breeders to develop a resistant variety or pathologists to monitor the dynamics of pathogenic isolates, and ultimately to control the disease. Here, we summarize the current status of the isolation of R, qR and Avr genes in the rice–M. oryzae interaction system, and review the progresses and problems of these genes utilized in practice for reducing rice blast disease. Research perspectives towards better managing blast disease by developing a broad-spectrum and durable blast resistance variety and new fungicides are also discussed.

Rice is a vital component in the diets of many people worldwide, supplying necessary calories for subsistence. Nevertheless, the yield of this crucial agricultural crop is consistently hindered by a range of biotic stresses. Out of these, rice blast, claused mainly by the fungus Magnaporthe oryzae, poses a significant menace to worldwide rice cultivation as well as yield in recent years. The consequences are particularly crucial given the current climate change challenges. In recent decades, substantial progress has been achieved in the development of efficient ways to manage rice blast disease. These procedures entail using a variety of rice genetic resources to find, map, clone, and functionally validate individual resistance (R) genes and quantitative trait loci (QTLs) that provide long-lasting resistance to rice blast disease. Moreover, the replication and practical confirmation of homologous avirulence (Avr) genes in various M. oryzae strains have been crucial in comprehending the fundamental molecular mechanisms of host–pathogen interactions. This article offers a thorough examination of the cloning and functional verification of different R genes and QTLs linked to resistance against rice blast disease. The complex interplay between R–Avr pairings, which contributes to the development of resistance against rice blast throughout a wide range, is thoroughly explained. Finally, this study explores the most recent progress in next-generation sequencing (NGS) and genome editing technologies (GETs), examining their potential uses in improving the treatment of rice blast disease.

Chemical fertilizers are commonly used to meet the nutritional demands of crops and boost their yields. However, their high costs and excessive application in soils increase the cost of production and have negative effects on the soil and environmental health. Vermicompost is an organic amendment that can potentially lessen the dependence on chemical fertilizers, with the additional advantages of sustainable nutrient supply to crops and maintaining soil health. To evaluate the potential of the two diverse vermicompost, the sole and combined applications of these vermicompost with reduced rates of chemical fertilizers were used for tomato cultivation in a field study. The results indicated that vermicompost produced from cattle manure combined with chemical fertilizers was more effective in improving tomato growth, physiology, yield, and nutritional attributes. Compared to the control treatment (NP applied), the combined application of vermicompost and chemical fertilizer significantly improved the root length (21.6%), plant height (167%), SPAD value (13.5%), chlorophyll ‘a’ (96%), chlorophyll ‘b’ (161%), relative water content (16%), membrane stability index (18%), carotenoid (87%), yield (82%), photosynthetic rate (148%), fruit diameter (83%), protein (89%), fat (27.5%), fiber (12%), vitamin C (52%), calcium (54%), magnesium (117%), phosphorus (38%) and potassium (128%). In addition, significant improvements in different soil physicochemical properties were also pragmatic. The results suggest that vermicompost application with reduced doses of chemical fertilizers can be used to improve crop yield and soil physico-chemical properties.

Rice blast, caused by the Magnaporthe oryzae fungus, is one of the most devastating rice diseases worldwide. Developing resistant varieties by pyramiding different blast resistance (R) genes is an effective approach to control the disease. However, due to complex interactions among R genes and crop genetic backgrounds, different R-gene combinations may have varying effects on resistance. Here, we report the identification of two core R-gene combinations that will benefit the improvement of Geng (Japonica) rice blast resistance. We first evaluated 68 Geng rice cultivars at seedling stage by challenging with 58 M. oryzae isolates. To evaluate panicle blast resistance, we inoculated 190 Geng rice cultivars at boosting stage with five groups of mixed conidial suspensions (MCSs), with each containing 5–6 isolates. More than 60% cultivars displayed moderate or lower levels of susceptibility to panicle blast against the five MCSs. Most cultivars contained two to six R genes detected by the functional markers corresponding to 18 known R genes. Through multinomial logistics regression analysis, we found that Pi-zt, Pita, Pi3/5/I, and Pikh loci contributed significantly to seedling blast resistance, and Pita, Pi3/5/i, Pia, and Pit contributed significantly to panicle blast resistance. For gene combinations, Pita+Pi3/5/i and Pita+Pia yielded more stable pyramiding effects on panicle blast resistance against all five MCSs and were designated as core R-gene combinations. Up to 51.6% Geng cultivars in the Jiangsu area contained Pita, but less than 30% harbored either Pia or Pi3/5/i, leading to less cultivars containing Pita+Pia (15.8%) or Pita+Pi3/5/i (5.8%). Only a few varieties simultaneously contained Pia and Pi3/5/i, implying the opportunity to use hybrid breeding procedures to efficiently generate varieties with either Pita+Pia or Pita+Pi3/5/i. This study provides valuable information for breeders to develop Geng rice cultivars with high resistance to blast, especially panicle blast.