Stomata are crucial structures in plants that play a primary role in the infection process during a pathogen’s attack, as they act as points of access for invading pathogens to enter host tissues. Recent evidence has revealed that stomata are integral to the plant defense system and can actively impede invading pathogens by triggering plant defense responses. Stomata interact with diverse pathogen virulence factors, granting them the capacity to influence plant susceptibility and resistance. Moreover, recent studies focusing on the environmental and microbial regulation of stomatal closure and opening have shed light on the epidemiology of bacterial diseases in plants. Bacteria and fungi can induce stomatal closure using pathogen-associated molecular patterns (PAMPs), effectively preventing entry through these openings and positioning stomata as a critical component of the plant’s innate immune system; however, despite this defense mechanism, some microorganisms have evolved strategies to overcome stomatal protection. Interestingly, recent research supports the hypothesis that stomatal closure caused by PAMPs may function as a more robust barrier against pathogen infection than previously believed. On the other hand, plant stomatal closure is also regulated by factors such as abscisic acid and Ca²⁺-permeable channels, which will also be discussed in this review. Therefore, this review aims to discuss various roles of stomata during biotic and abiotic stress, such as insects and water stress, and with specific context to pathogens and their strategies for evading stomatal defense, subverting plant resistance, and overcoming challenges faced by infectious propagules. These pathogens must navigate specific plant tissues and counteract various constitutive and inducible resistance mechanisms, making the role of stomata in plant defense an essential area of study.

The tomato (Solanum lycopersicum L.) is consumed globally as a fresh vegetable due to its high nutritional value and antioxidant properties. However, soil-borne diseases can severely limit tomato production. These diseases, such as bacterial wilt (BW), Fusarium wilt (FW), Verticillium wilt (VW), and root-knot nematodes (RKN), can significantly reduce the yield and quality of tomatoes. Using agrochemicals to combat these diseases can lead to chemical residues, pesticide resistance, and environmental pollution. Unfortunately, resistant varieties are not yet available. Therefore, we must find alternative strategies to protect tomatoes from these soil-borne diseases. One of the most promising solutions is harnessing microbial communities that can suppress disease and promote plant growth and immunity. Recent omics technologies and next-generation sequencing advances can help us develop microbiome-based strategies to mitigate tomato soil-borne diseases. This review emphasizes the importance of interdisciplinary approaches to understanding the utilization of beneficial microbiomes to mitigate soil-borne diseases and improve crop productivity.

Since time immemorial organic amendments have been an important strategy for improving soil fertility and suppressing a wide range of soil-borne pathogens. Biochar, a charcoal-like amendment has true potential in managing phytopathogens with an eco-friendly approach. It is produced by subjecting plant materials and agricultural waste to high temperatures of around 900°C in limited oxygen conditions. Biochar is considered to be an excellent carbon sequester and has an undeniably imperative role in improving soil properties. Biochar has innumerable applications in the remediation of environmental pollutants by immobilizing heavy metals such as Cadmium and Arsenic and degradation of dyes and pesticides. One of the most significant advantages of biochar in addition to mitigating environmental pollution is effectively managing plant pathogens by altering soil physical and chemical properties and promoting antagonistic microorganisms. Biochar directly suppresses plant pathogens by priming plant defense mechanisms. For instance, sugarcane bagasse biochar remediates Cd from contaminated soil, and citrus wood biochar induces systemic resistance against Botrytis cinerea in host-Lycopersicon esculentum, Capsicum annuum L. cv. Maccabi and Fragaria ananassa. Nevertheless, it is essential to acknowledge its limitations, such as the potential to absorb and enhance the residual activity of harmful chemicals. Further research is needed to develop a deeper understanding of biochar’s properties and mechanisms for more effective results. Advanced techniques like meta-transcriptomics and metaproteomics hold the potential to provide invaluable insights into this field. The review provides a comprehensive overview of current information regarding biochar, covering its production techniques and highlighting its agricultural benefits, with a particular focus on its role in plant disease management. Furthermore, the associated risks and concerns are also discussed.

Maize is the third most vital global cereal, playing a key role in the world economy and plant genetics research. Despite its leadership in production, maize faces a severe threat from banded leaf and sheath blight, necessitating the urgent development of eco-friendly management strategies. This study aimed to understand the resistance mechanisms against banded leaf and sheath blight (BLSB) in maize hybrid “Vivek QPM-9”. Seven fungicides at recommended doses (1000 and 500 ppm) and two plant defense inducers, salicylic acid (SA) and jasmonic acid (JA) at concentrations of 50 and 100 ppm, were applied. Fungicides, notably Azoxystrobin and Trifloxystrobin + Tebuconazole, demonstrated superior efficacy against BLSB, while Pencycuron showed limited effectiveness. Field-sprayed Azoxystrobin exhibited the lowest BLSB infection, correlating with heightened antioxidant enzyme activity (SOD, CAT, POX, β-1,3-glucanase, PPO, PAL), similar to the Validamycin-treated plants. The expression of defense-related genes after seed priming with SA and JA was assessed via qRT-PCR. Lower SA concentrations down-regulated SOD, PPO, and APX genes but up-regulated CAT and β-1,3-glucanase genes. JA at lower doses up-regulated CAT and APX genes, while higher doses up-regulated PPO and β-1,3-glucanase genes; SOD gene expression was suppressed at both JA doses. This investigation elucidates the effectiveness of certain fungicides and plant defense inducers in mitigating BLSB in maize hybrids and sheds light on the intricate gene expression mechanisms governing defense responses against this pathogen.

Plants are under constant exposure to varied biotic and abiotic stresses, which significantly affect their growth, productivity, and survival. Biotic stress, caused by pathogens, and abiotic stress, including drought, salinit... | Find, read and cite all the research you need on Tech Science Press

Vegetable production is challenged by a range of biotic and abiotic factors, often resulting in a substantial loss of the produce in each growing cycle. Unfortunately, abiotic stresses are becoming increasingly more prevalent especially in light of climate change. Like many cultivated plants, the tomato needs a variety of mineral elements to ensure its growth throughout its development cycle. When they are provided in excess or they are lacking, nutritional disorders occur. Blossom-end rot (BER) is a physiological disorder causing severe losses in tomato crops. Calcium deficiency is widely accepted as the main factor responsible for BER appearance in tomato (Solanum lycopersicum L.) fruit due to water logged soil conditions, transpiration and abiotic stresses. However, reactive oxygen species (ROS), which can damage plant tissues, have also been proposed to initiate BER appearance in tomatoes and other fruitbearing vegetables. Ascorbate, the major antioxidant in tomato fruit, is generally lower during green fruit development, which corresponds to the stage of BER appearance. Tomato varieties with elongated fruit usually have a greater susceptibility to BER than other varieties. When the tomato grows the lesions get darker, becomes leathery and can cover half the fruits bottom. The present review article deals with all the aspects of blossom end rot (BER) of tomato including the causes, symptoms, epidemiology and management.