Project description:Tomato plants are submitted to a high diversity of herbivory pests, among them the leafminer Tuta absoluta, considered as one of the most important threat on the tomato worldwide production. In spite of its susceptibility to this pest, a better understanding of the tomato plant response to T. absoluta herbivory will help defining plant resistance traits and enlarging the range of possibilities for an efficient integrated pest management strategy. We analyzed the transcriptomic response in leaves of tomato (cv. Better Bush) submitted to the herbivory of T. absoluta larvae after 5h and 24h.
2022-04-18 | GSE200795 | GEO
Project description:Immunological responses and gut microbial shifts in Phthorimaea absoluta exposed to entomopathogenic fungi.
Project description:The leaf miner, Tuta absoluta, is a notorious destructive pest of tomato that causes important losses worldwide. Breeding of resistant/tolerant tomato cultivars could be an effective strategy for T. absoluta management but, despite the economic importance of tomato, very limited information is available about its response to this treat. To elucidate the defense mechanisms to the herbivore feeding a comparative analysis was performed between a tolerant and susceptible cultivated tomato at both morphological and at transcriptome level to highlight constitutive leaf barriers, molecular and biochemical mechanisms to counter the effect of T. absoluta attack. The tolerant genotype showed an enhanced constitutive barrier due to the higher density of trichomes and increased inducible reactions upon mild infestation thanks to the activation/repression of key transcription factors regulating a higher number of genes involved in cuticle formation and cell wall strength as well as of antinutritive enzymes, and genes involved in the production of chemical toxins and bioactive secondary metabolites. Overall, our findings provide an important foundation for further understanding the insect resistance mechanisms of resistant/tolerant varieties that can be exploited for developing T. absoluta tolerant cultivars, acting as important component of integrated pest management strategy for more sustainable production.
Project description:Tomato leafminer (Tuta absoluta) is a major pest of solanaceous plant species and causes heavy economic losses to the tomato crop. T. absoluta have been developed resistance to many chemical insecticides and have serious impacts on human health as well as environment. To overcome the ill effects of insecticides, ecofriendly approachis needed and among various biological microbes, entomopathogenic fungi is reliable and cost effective. The entomopathogenic fungi, like Beauveria bassiana and Purpureocillium lilacinum have ability to control pest population. The present study was conducted to study the interaction of B. bassiana and P. lilacinum at proteomic level to understand post infection effects. The analysis showed that in fourth instar larvae of T. absoluta, and the 442 and 423 proteins were significantly dysregulated upon infection with P. lilacinum and B. bassiana respectively. The present study concluded entomopathogenic fungal infection decline the immune system of T. absoluta larvae and can be adopted in for control of T. absoluta insect pest.
Project description:Plants communicate with each other using specific volatiles to warn of attacks and thus are able to activate defense mechanisms that make them more robust against external aggressions. In this research, we have activated defense responses of tomato plants by exposing them to two synthetic Herbivore Induced Plant Volatiles (HIPVs): (Z)-3-hexenyl propanoate (HP) [(Z)-3-HP] and methyl salicylate (MeSA). Tomato plants induced by both volatiles turned out to be less attractive to key tomato pests such as Bemisia tabaci and Tuta absoluta and more attractive to natural enemies. Under semi-field conditions the (Z)-3-HP-mediated activation reduced the subsequent attack of Tetranychus urticae and T. absoluta to less than half. With this knowledge, dispensers to release (Z)-3-HP under field conditions were designed and calibrated. The use of these selected dispensers in commercial tomato greenhouses maintained defensively activated plants and reduced the impact of T. absoluta by almost 60%. Metabolomics analysis indicated increased production of fatty acid-derived compounds in treated leaves, consistent with the activation of the lipoxygenase pathway. Plants elicited with (Z)-3-HP and MeSA also accumulated specific defense compounds like glykoalkaloids and phenylpropanoids. Transcriptomic profiling confirmed the activation of transcripts involve in defense (ie. proteinase inhibitors) and specialized defense metabolism. Our work demonstrates for the first time under real field conditions how the use of HIPVs as elicitors of plant defenses can be successfully integrated as a new biorational and sustainable tool within pest management programs.