Biology, Taxonomy, and Management of the Root-Knot Nematode (Meloidogyne incognita) in Sweet Potato

Abstract

Sweet potato is the seventh-ranked food crop produced after wheat, rice, maize, potato, barley, and cassava in the world. It is the most important root tuber crop in temperate, subtropical, and tropical areas of the world. It is grown for food, income-generating, and jobs for farmers and retailers. The important nutritional substances of sweet potatoes are ß-carotene and anthocyanins. However, the production and its valuable products are limited due to root-knot nematode parasitism. One of the most important destructive species of root-knot nematode to this crop is Meloidogyne incognita. The most destructive stage to sweet potato is at its second juvenile stage (J2). At this stage, it invades the roots and tubers of sweet potato highly in warm sandy soil conditions. It is an obligate plant-parasitic nematode. M. incognita caused significant yield loss to sweet potato in terms of quality, quantity, disturbing the process of photosynthesis and nutrient uptake through the formation of galling, establishing of its feeding sites, or induced galls that contain giant-feeding cells, and cracking of tubers and roots directly. It also reduces the market values of the infected tuber of sweet potato by downgrading the production values. The problem of quality and quantity losses to sweet potato by this pest is one of the major problems nowadays. It caused this problem alone or interaction with other plant-parasitic pathogens or through synergistic of fungi, bacteria, viruses, and others. Therefore, this review paper is focused on the sweet potato M. incognita biology, taxonomy, geographical distribution, and management measures.

Sources of root-knot nematode (Meloidogyne enterolobii) resistance in sweetpotato genotypes

“…However, M. enterolobii Yang & Eisenback (1983) (syn. M. mayaguensis, Ramah & Hirschmann, 1988) is gaining notoriety, due to its ability to infect resistant plants to other RKN species (Rutter et al, 2019;Carmona et al, 2020;Silva et al, chlorosis, plant death, leaf wilting, poor shoot growth, and the development of root cracks in some cultivars or pimplelike bumps in others, presence of dark areas within the flesh, with the presence of enlarged females and their egg masses (Bernard et al, 2017;Wendimu, 2021). This causes great concern, especially in the tropics, subtropics and warm regions all around the world (Karuri et al, 2017;Rutter et al, 2019;Brito et al, 2020; D espite being considered a rustic plant species, sweetpotato (Ipomoea batatas) is a susceptible host to different root-knot nematodes (RKN) of the genus Meloidogyne (Villordon & Clark, 2018).…”

Effect of Soil Amendments on the Growth Parameters of Okra Infested with Root-Knot Nematode (Meloidogyne incognita)

“…The root knot nematode species, M. incognita, is the most widespread and probably the most serious plant parasitic nematode pest of tropical and subtropical regions throughout the world. It occurs as a pest on a very wide range of crops Wendimu [7]. Though M. incognita is found on many soil types, damage and yield losses caused are generally more severe on coarsetextured sandy soils.…”

Biosynthesis of Cry5B-Loaded Sulfur Nanoparticles using Arthrobotrys oligospora Filtrate: Effects on Nematicidal Activity, Thermal Stability, and Pathogenicity against Caenorhabditis elegans

“…2 Meloidogyne incognita (M. incognita) is among the most economically significant nematodes in tropical and subtropical areas that are difficult to control because they spend most of their lives within plant roots, rendering them resistant to conventional control methods. 3 Currently, plantparasitic nematode control is primarily based on chemical nematicides, which have resulted in severe environmental issues and the emergence of PPN strains with chemical resistance. As a result, biological agents, bioactive compounds derived from plants and microorganisms, such as fungi and bacteria, as well as innovative nanoparticle delivery systems for bionematicides, have gained attention for the control of PPNs.…”

“…Meloidogyne incognita (M. incognita) is among the most economically significant nematodes in tropical and subtropical areas that are difficult to control because they spend most of their lives within plant roots, rendering them resistant to conventional control methods . Currently, plant-parasitic nematode control is primarily based on chemical nematicides, which have resulted in severe environmental issues and the emergence of PPN strains with chemical resistance.…”