Integrated cultural practices for whitefly management in organic tomato

Abstract

The whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) is a serious pest among the diverse insect fauna of the tomato crop, especially when cultivated in organic systems. The feeding behaviour of B. tabaci is responsible for direct damage to tomato plants and for the transmission of several viruses, such as begomoviruses. The objective of this study was to evaluate the effect of integrating the cultural practices of intercropping and irrigation systems on B. tabaci abundance and the incidence of begomovirus in organic tomato systems. Field experiments were performed in the dry season for 2 years when B. tabaci abundance and begomovirus incidence were compared in tomato crops planted either in monoculture or intercropped with coriander and irrigated by overhead sprinklers or by a drip irrigation system. Tomato plants intercropped with coriander and irrigated by overhead sprinklers showed the lowest levels of B. tabaci colonization by adult and nymph densities. Most likely, the coriander plants produced visual and olfactory barriers for insect host plant selection, and the overhead sprinkler irrigation physically interfered with the movement and establishment of the insects. The combined effect of intercropping and sprinkler irrigation made tomato plants less suitable for B. tabaci establishment. Moreover, tomatoes intercropped with coriander and irrigated by sprinkler irrigation also reduced the incidence of begomovirus‐infected plants. In summary, integrating tomato–coriander intercropping and sprinkler irrigation can help manage B. tabaci and associated viruses in organic tomato crops.

Bemisia tabaci on Vegetables in the Southern United States: Incidence, Impact, and Management

“…Intercropping to prevent B. tabaci from locating host plants has shown promise. Lower B. tabaci densities and/or incidence of associated viruses were observed on tomato intercropped with coriander [135,145,171], squash [172], maize [142], chili pepper (Capsicum annuum L.) [173], cucumber [169,174], French bean (Phaseolus vulgaris L.) [175], onion (Allium cepa L.) [176], and garlic (Allium sativum L.) [176]. Additionally, intercropping okra with coriander or ginger (Zingiber officinale L.) has been reported as one alternative strategy to suppress B. tabaci populations in okra [177,178].…”

“…Water and fertility management plays a vital role as a cultural tactic in B. tabaci control on vegetable plants [131][132][133][134][135][136][137]. For instance, compared to furrow and sprinkler irrigation, daily drip irrigation resulted in the lowest B. tabaci density and incidence of whitefly-transmitted viruses in cucumber, green bean, squash, and tomato [132].…”

“…For instance, compared to furrow and sprinkler irrigation, daily drip irrigation resulted in the lowest B. tabaci density and incidence of whitefly-transmitted viruses in cucumber, green bean, squash, and tomato [132]. However, when integrating with the tomato-coriander (Coriandrum sativum L.) intercropping strategy, sprinkler irrigation reduced B. tabaci and associated viruses on organic tomato crops [135]. Moreover, increasing nitrogen levels increased B. tabaci populations in okra [131] and hydroponic tomato [136].…”

Whitefly (Bemisia tabaci) Management (WFM) Strategies for Sustainable Agriculture: A Review

“…Drip irrigation reduces whitefly density and viruses transmitted by them in several crops compared to furrow/sprinkler irrigation [109]. Irrigation using sprinkler technique was also reported to decrease the whitefly population and related viruses in tomatoes intercropped with the coriander plant [110]. Sulfur-containing fertilizers have variable impacts on whitefly population in different crops [111].…”

Population Dynamics of Whiteflies and Associated Viruses in South America: Research Progress and Perspectives

“…Studies conducted in Costa Rica have shown that intercropping with tomatoes and coriander plants (Coriandrum sativum L.) in open fields caused a reduction in whiteflies' incidence and plants with viruses [212]. Other tests carried out in the Federal District region of Brazil, in tomato crops associated with coriander plants and sprinkler irrigation systems, have shown promising results in reducing the infestation of B. tabaci and incidence of damage caused by begomoviruses in periods of greater susceptibility of tomato culture [213]. More studies are still necessary to establish the best spacing of these repellent barriers to increase their efficacy.…”