Plants And Pest

Neuropeptides are involved in many biological processes in insects. However, it is unclear what role neuropeptides play in Spodoptera litura adaptation to phytochemical flavone. In this study, 63 neuropeptide precursors from 48 gene families were identified in S. litura , including two neuropeptide F genes ( NPFs ). NPFs played a positive role in feeding regulation in S. litura because knockdown of NPFs decreased larval diet intake. S. litura larvae reduced flavone intake by downregulating NPFs . Conversely, the flavone intake was increased if the larvae were treated with NPF mature peptides...

Coffea arabica L. is a crucial crop globally, but its genetic homogeneity leads to its susceptibility to diseases and pests like the coffee berry borer (CBB). Chemical and cultural control methods are difficult due to the majority of the CBB life cycle taking place inside coffee beans. One potential solution is the use of the gene cyt1Aa from Bacillus thuringiensis as a biological insecticide. To validate candidate genes against CBB, a simple, rapid, and efficient transient expression system is necessary. This study uses cell suspensions as a platform for expressing the cyt1Aa gene in the coffee genome (C...

Plant volatile organic compounds (VOCs) are organic chemicals that plants release as part of their natural biological processes. Various plant tissues produce VOCs, including leaves, stems, flowers, and roots. VOCs are essential in plant communication, defense against pests and pathogens, aroma and flavor, and attracting pollinators. The study of plant volatiles has become an increasingly important area of research in recent years, as scientists have recognized these compounds' important roles in plant physiology...

Bermudagrass mite (Aceria cynodoniensis Sayed) infestation stunts bermudagrass (Cynodon spp. [Poales: Poaceae]) growth, leading to thinned turf and lower aesthetic and recreational value. Bermudagrass mites cause characteristic symptoms called witch's brooms, including shortened internodes and leaves and the proliferation of tillers. Grass clippings produced by mowing or scalping bermudagrass harbor mites, which abandon the desiccating grass clippings and spread to surrounding turfgrass. Dropped grass clippings can lead to infestation of new turfgrass...

Durable host plant resistance (HPR) to insect pests is critical for sustainable agriculture. Natural variation exists for aphid HPR in sorghum (Sorghum bicolor), but the genetic architecture and phenotype have not been clarified and characterized for most sources. In order to assess the current threat of a sorghum aphid (Melanaphis sorghi) biotype shift, we characterized the phenotype of Resistance to Melanaphis sorghi 1 (RMES1) and additional HPR architecture in globally admixed populations selected under severe sorghum aphid infestation in Haiti...

Phthorimaea absoluta is a global constraint to tomato production and can cause up to 100% yield loss. Farmers heavily rely on synthetic pesticides to manage this pest. However, these pesticides are detrimental to human, animal, and environmental health. Therefore, exploring eco-friendly, sustainable Integrated Pest Management approaches, including biopesticides as potential alternatives, is of paramount importance. In this context, the present study (i) evaluated the efficacy of 10 Bacillus thuringiensis isolates, neem, garlic, and fenugreek; (ii) assessed the interactions between the most potent plant extracts and B...

Following the commodity risk assessments of Acer palmatum plants grafted on A. davidii from China, in which Crisicoccus matsumotoi (Hemiptera: Pseudococcidae) was identified as a pest of possible concern, the European Commission requested the EFSA Panel on Plant Health to conduct a pest categorisation of C. matsumotoi for the territory of the European Union. Recent taxonomic revision of the genus Crisisoccus concluded that C. matsumotoi is a synonym of C. seruratus ; therefore, the categorisation will use the current valid name C...

The reniform nematode, Rotylenchulus reniformis , is a major yield-limiting pest of upland cotton ( Gossypium hirsutum ) in the United States that has been steadily increasing in incidence in many states. Reniform nematode-resistant cotton cultivars have recently become commercially available for cotton producers; however, few field trials have evaluated their efficacy as a nematode management tool. The aim of this study was to evaluate reniform nematode population development, plant growth, and seed cotton yield of reniform nematode-resistant cotton cultivars in two nematode-infested fields in Louisiana...

Triterpenoid saponins, synthesized via the mevalonic acid (MVA) pathway in the cytoplasm, provide protection against pathogens and pests in plants and health benefits for humans. However, the mechanisms by which triterpenoid saponins are transported between cellular compartments remain uncharacterized. Here, we characterize a tonoplast localized multidrug and toxic compound extrusion transporter, GmMATE100 (encoded by Glyma.18G143700 ), from soybean ( Glycine max L.). GmMATE100 is co-expressed with soyasaponin biosynthetic genes, and its expression was induced by MeJA treatment, which also led to soyasaponin accumulation in soybean roots...

The Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), is a crop pest of global economic importance because of its wide range of hosts and its invasiveness capacities. To develop a novel integrated and sustainable crop protection, we have investigated the insecticidal properties of different varieties of kava (Piper methysticum [Frost]) extracted by two methods and the attractive effects of six plant volatiles identified from B. tryoni host plants to female, mated or not. We did not identify any significant insecticidal effect of the traditional Pacific kava plant at the tested concentrations...

Cover crops, a soil conservation practice, can contribute to reducing disease pressure caused by Pseudomonas syringae, considered one of the most important bacterial plant pathogens. We recently demonstrated that phyllosphere (leaf surface) bacterial community structure changed when squash (Cucurbita pepo) was grown with a rye (Secale cereale) cover crop treatment, followed by a decrease of angular leaf spot (ALS) disease symptoms on squash caused by P. syringae pv. lachrymans. Application of biocontrol agents is a known agricultural practice to mitigate crop losses due to microbial disease...

The production of herbivore-induced plant volatiles (HIPVs) is a type of indirect defense used by plants to attract natural enemies and reduce herbivory by insect pests. In many crops little is known about genotypic variation in HIPV production or how this may affect natural enemy attraction. In this study, we identified and quantified HIPVs produced by 10 sorghum (Sorghum bicolor) cultivars infested with a prominent aphid pest, the sorghum aphid (Melanaphis sorghi Theobald). Volatiles were collected using dynamic headspace sampling techniques and identified and quantified using GC-MS...

BACKGROUND: Xylella fastidiosa is a multi-host bacterium that can be detected in hundreds of plant species including several crops. Diseases caused by X. fastidiosa are considered a threat to global food production. The primary method for managing diseases caused by X. fastidiosa involves using insecticides to control the vector. Hence, it is necessary to adopt new and sustainable disease management technologies to control not only the insect but also the bacteria and plant health. We demonstrated that N-Acetylcysteine (NAC), a low-cost cysteine analogue, is a sustainable molecule that can be used in agriculture to decrease the damage caused by X...

BACKGROUND: Aphids (Hemiptera: Aphididae) are notorious sap-sucking insects that rampantly threaten agricultural production worldwide. Current management against aphids in the field heavily relies on chemical pesticides, which makes economical and eco-friendly methods urgently needed. Spray-induced gene silencing (SIGS) offers a powerful and precise approach to pest management. However, the high costs and instability of double-stranded RNA (dsRNA) regulators applied for downstream RNA interference (RNAi) still limit this strategy...

Plants have evolved distinct defense strategies in response to a diverse range of chewing and sucking insect herbivory. While chewing insect herbivores, exemplified by caterpillars and beetles, cause visible tissue damage and induce jasmonic acid (JA)-mediated defense responses, sucking insects, such as aphids and whiteflies, delicately tap into the phloem sap and elicit salicylic acid (SA)-mediated defense responses. This review aims to highlight the specificity of defense strategies in Brassica plants and associated underlying molecular mechanisms when challenged by herbivorous insects from different feeding guilds (i...

The natural occurrence, distribution (within a plant) and roles of four phenylbutanoid compounds (anisyl acetone, cue-lure, raspberry ketone and zingerone) are elucidated for the Asia-Pacific and Oceania regions. These phenylbutanoids may act individually or in combination to attract true fruit fly males belonging to a tribe Dacini of subfamily Dacinae (Diptera: Tepritidae). Of special interest are the mutualistic interactions between the Dacini fruit fly males and the tropical daciniphilous (attracting exclusively Dacini fruit flies) orchids - leading to cross pollination for the orchids and enchanced mating success for the flies...

Euwallacea fornicatus is an invasive tree pest able to infest healthy plants and cause damage to many host plants. This beetle has become established in several countries where it was introduced. It has now become established in Brazil, and while the original introduction site remains uncertain, there is a possibility of multiple introductions. We report the first evidence for the establishment of E. fornicatus with molecular confirmation, as well as its distribution, and host plants in Brazil. Euwallacea fornicatus has spread to main commercial avocado groves, other monocultures, and native vegetation in the country, and its pest status puts it as a threat, mainly to Brazilian avocado producers...

The cultivation of grapes encounters various challenges, such as the presence of pests and diseases, which have the potential to considerably diminish agricultural productivity. Plant diseases pose a significant impediment, resulting in diminished agricultural productivity and economic setbacks, thereby affecting the quality of crop yields. Hence, the precise and timely identification of plant diseases holds significant importance. This study employs a Convolutional neural network (CNN) with and without data augmentation, in addition to a DCNN Classifier model based on VGG16, to classify grape leaf diseases...

Scirpophaga incertulas Walker (Lepidoptera: Crambidae, yellow stem borer, YSB) is a monophagous insect pest that causes significant yield loss in rice (Oryza staiva L.). Semiochemical based pest management is being sought as an alternate to chemical pesticides to reduce pesticide footprints. We hypothesized differential release of volatiles from host rice and two companion non-host weeds, Echinochloa colona and Echinochloa crus-galli could be responsible for oviposition and biology of YSB and these chemicals could be used for YSB management...

The sweet potato whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) is responsible for significant crop losses and presents one of the greatest challenges for global agricultural pest management. Management of whitefly populations and associated plant viral diseases is hindered by widespread whitefly resistance to chemical insecticides. An alternative control approach involves the use of insect-specific neurotoxins, but these require delivery from the whitefly gut into the haemocoel. Here we demonstrate that the coat protein (CP) of a begomovirus, Tomato yellow leaf curl virus, is sufficient for delivery of fused proteins into the whitefly haemocoel without virion assembly...