Whitefly Control Strategies against Tomato Leaf Curl New Delhi Virus in Greenhouse Zucchini

Abstract

(1) Background: Tomato leaf curl New Delhi virus (ToLCNDV), transmitted by tobacco whitefly (Bemisia tabaci Gennadius) (Hemiptera: Aleyrodidae), is of major concern in the cultivation of zucchini. The threat of this virus motivates reliance on chemical vector control but European consumers’ demands for vegetables grown free of pesticides provides an important incentive for alternative pest management; (2) Methods: Different whitefly management strategies and ToLCNDV incidences were surveyed in commercial zucchini greenhouses in south-east Spain. In an experimental greenhouse, three different whitefly control strategies, biological, chemical, and integrated (IPM), were evaluated in a replicated trial to determine the most effective strategy for virus suppression (3) Results: Whitefly was present in all commercial zucchini crops surveyed, whereas fewer crops had Amblyseius swirskii or other natural enemies. During three consecutive years, pest management was increasingly based on chemical treatments. Yet, ToLCNDV was widespread in zucchini greenhouses. Experimental results showed that the order of best strategy for virus suppressing was integrated management (73%) > biological control (58%) > chemical control (44%); and (4) Conclusions: IPM was the best strategy for virus suppression. The results can assist in the design of appropriate control strategies for chemical pesticide reduction and decision-making in pest management.

A Historical Account of Viruses in Intensive Horticultural Crops in the Spanish Mediterranean Arc: New Challenges for a Sustainable Agriculture

“…In a recent report, integrated management was revealed as the best strategy to control ToLCDV spread in greenhouse-grown zucchini, followed by biological and chemical control, in this order [123]. Nevertheless, efforts to move to biological controls are being taken into consideration because of public concerns [124].…”

A Review of the Biology and Control of Whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), with Special Reference to Biological Control Using Entomopathogenic Fungi

“…The effect of chemical pesticides on the non-target organism, environmental contamination, and resistance of insect pests have led to research on biological control agents as alternative control measures. B. tabaci can be effectively controlled by integrating multiple biological control agents such as parasitoids, predators, and EPF [ 45 , 71 , 72 , 73 , 74 , 75 , 76 ].…”

Response of Cucurbita spp. to tomato leaf curl New Delhi virus inoculation and identification of a dominant source of resistance in Cucurbita moschata

“…Dominant resistance to specific viruses--and also to some varieties of fungi and bacteria--is normally conferred by resistance genes (R genes), the majority of which encode nucleotide-binding domain and leucine-rich repeat proteins (NBS-LRR). These are able to initiate a resistant, hypersensitive response upon interaction with a pathogenic avirulence (Avr) determinant (Maule et al, 2007;de Ronde et al, 2014). In contrast, recessive resistance is usually conferred by mutations in susceptibility genes (S genes), which encode plant proteins that are required by the pathogen for interaction, movement, or replication within the host plant (Truniger and Aranda, TA B L E 4 Segregation of ToLCNDV resistance in F 1 , F 2 , and BC 1 generations derived from the cross between BSUAL-252 (resistant) and BSUAL-265 (susceptible) accessions of Cucurbita moschata 2009).…”

“…Most efforts to control viruses have focused on vector management by insecticide applications and the use of physical barriers in greenhouses. Additionally, agricultural practices such as elimination of infected plants, weed management, and the deployment of natural enemies of whiteflies are recommended (Rodríguez et al ., 2019). However, the effectiveness of these strategies is uncertain because the vector sometimes overcomes any physical or chemical treatment (Snehi et al, , 2015).…”