Biotechnological advances with applicability in potatoes for resistance against root-knot nematodes

Comprehensive review of plant small signaling peptides: From stress adaptation mechanisms to practical solutions for crop resilience

Small signaling peptides (SSPs), short proteins of fewer than 100 amino acids, serve as pivotal signaling molecules with diverse structural features, post-translational modifications, and functional roles. They regulate various aspects of plant growth and development by modulating specific cellular signaling pathways. Research has shown that many SSPs are essential for mediating responses to environmental stresses. This review presents the structure, characteristics, and classification of plant SSPs and elucidates their roles in resistance signaling pathways through interactions with their specific receptors. We then summarize recent findings on the biological functions and regulatory mechanisms of SSPs in response to both biotic and abiotic stresses. Finally, we discuss the potential applications and future prospects of these peptides in plant protection. This review offers valuable insights for enhancing plant resilience to environmental stress and advancing sustainable agricultural practices, while also providing key references and perspectives to accelerate research on SSPs in plants.

Activity of chitin/chitosan/chitosan oligosaccharide against plant pathogenic nematodes and potential modes of application in agriculture: A review

Chemical nematicide is the most common method of controlling plant-parasitic nematodes (PPN). Given the negative impact of chemical nematicides on the environment and ecosystem, it is necessary to seek their alternatives and novel modes of application. Chitin oligo/polysaccharide (COPS), including chitosan and chitosan oligosaccharide, has unique biological properties. By producing ammonia, encouraging the growth of antagonistic bacteria, and enhancing crop tolerance, COPSs help suppress PPN growth during soil remediation. COPS is also an effective sustained-release carrier that can be used to overcome the shortcomings of nematicidal substances. This review summarizes the advancements of COPS research in nematode control from three perspectives of action mechanism as well as in slow-release carrier-loaded nematicides. Further, it discusses potential agricultural applications for nematode disease management.

A molecular beacon real-time polymerase chain reaction assay for the identification of M. chitwoodi, M. fallax, and M. minor

Root-knot nematodes (Meloidogyne spp.) are major pests of many important crops around the world. In the Northwestern region of the United States of America (USA), Meloidogyne chitwoodi causes economic losses in potatoes because the nematodes can infect the tubers, which leads to potato galling and reductions in marketable yield. Meloidogyne chitwoodi is a quarantine pathogen in certain potato export markets, and there is little industry tolerance for the presence of this nematode. Recently, two Meloidogyne species that are not known to be present in agricultural fields in the USA were detected on golf turfgrasses in California and Washington. These species, M. fallax and M. minor, are morphologically similar to M. chitwoodi and can infect potatoes and cause tuber damage. Their detection in the USA means that they could potentially infest potato fields and become a problem in potato production. Additionally, M. fallax is a regulated plant pest in the USA, which makes the correct identification of potato-infecting root-knot nematodes important. Previously, there was no single-tube assay that could determine whether M. chitwoodi, M. fallax, and/or M. minor were present in a sample. Thus, a molecular beacon real-time PCR assay which can reliably detect M. chitwoodi, M. fallax, or M. minor from crude nematode extracts was designed and characterized.

Application Potential of Bacterial Volatile Organic Compounds in the Control of Root-Knot Nematodes

Plant-parasitic nematodes (PPNs) constitute the most damaging group of plant pathogens. Plant infections by root-knot nematodes (RKNs) alone could cause approximately 5% of global crop loss. Conventionally, chemical-based methods are used to control PPNs at the expense of the environment and human health. Accordingly, the development of eco-friendly and safer methods has been urged to supplement or replace chemical-based methods for the control of RKNs. Using microorganisms or their metabolites as biological control agents (BCAs) is a promising approach to controlling RKNs. Among the metabolites, volatile organic compounds (VOCs) have gained increasing attention because of their potential in the control of not only RKNs but also other plant pathogens, such as insects, fungi, and bacteria. This review discusses the biology of RKNs as well as the status of various control strategies. The discovery of VOCs emitted by bacteria from various environmental sources and their application potential as BCAs in controlling RKNs are specifically addressed.