GuardSym · Disentangling the multitrophic interactions of the supervector Bemisia tabaci to potentially use its symbiotic communities to reduce plants viral-vectored diseases.

Disentangling the multitrophic interactions of the supervector Bemisia tabaci to potentially use its symbiotic communities to reduce plants viral-vectored diseases.

Agriculture is facing constant pressure to increase food production to fulfill human population demands. This has been accomplished by the use of intensive agricultural techniques. The increase in global temperatures together with intensive techniques like worldwide movements of plant material, use of monocultures, and abuse of insecticides have modified the trophic chains in agricultural systems. As a consequence, there is an unprecedented increase in emergent plant viral diseases in the last decades. Most of these viruses require an insect vector for their transmission. Unfortunately, some vector insects have been favored by intensive agriculture. Indeed, the whitefly Bemisia tabaci has become a worldwide supervector and is the cause of the global emergence of begomoviruses and criniviruses. This whitefly has developed resistance to many insecticides and developing new control techniques is a must. Recently, a population modification strategy has been applied to mosquitoes, displacing natural populations and replacing them with virus-resistant ones that are no longer able to transmit human diseases. This success has been achieved using Wolbachia, a bacterial symbiont present in many insects, that can confer virus-resistance phenotypes to its host. Interestingly, B. tabaci presents a rich bacterial symbiotic community, including Wolbachia, that can be naturally manipulated through hybridization. This offers the unique opportunity to unravel the multitrophic interactions that occur between B. tabaci, its symbionts, the vectored virus, and the plant. Using integrative frameworks to study the insect and plant physiology, the virus transmission, the dynamics of the symbionts, and the cross-talks between them (their transcriptomes) can lead to the discovery of new symbiotic virus-resistant phenotypes in B. tabaci. During the GuardSym action, two lines of B. tabaci carrying different symbiotic combinations but the same insect genetic background were generated. The Tomato Yellow Leaf Curly Virus (TYLCV) vectoring capabilities of the two lines obtained were compared to the parental and maternal lines. Whiteflies carrying TYLCV showed no differences in their survival or oviposition. Besides, the height, weight, and number of leaves of TYLCV symptomatic tomato plants were similar independently of the symbiotic community harbored by the insect. These results suggest that symbiotic communities induced TYLCV-resistance phenotypes neither in the insect host nor in the plant. Notwithstanding, it is possible that some resistance phenotypes could emerge in older plants or insects. Finally, both messenger RNA and small RNA were extracted from the two B. tabaci lines and tomato plants during the earlier and later stages of TYLCV disease. The molecular interactions between the insect, its symbionts, TYLCV, and the plant are currently under analysis.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз