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This study focuses on the assessment of the impact of climate change on the efficiency of ambient air aeration and the dynamics of Rhyzopertha dominica, which is a major pest that infests wheat stored in Tunisia. To project future climate conditions for the period 2041–2070, two climate models, namely MPI-ESM1.2 and CNRMCM5.1, were used under two representative concentration pathways (RCP4.5 and RCP8.5). The study examined the historical and projected feasibility of aeration in six natural regions located in northwestern Tunisia, where wheat is the main crop, and investigated the potential consequences of climate change on the dynamics of R. dominica. Using a heat and mass transfer model in an unaerated wheat silo, the temperature and moisture distributions in the grain mass were used to predict the development, reproduction, and survival of R. dominica. The results revealed a decline in favorable aeration hours due to climate change, resulting in an average reduction of 25% across the six regions. This reduction in aerated hours could significantly affect the effectiveness of aeration as a means of pest control. The mean difference comparisons, based on Tukey's honestly significant difference (HSD) test, revealed a significant effect of climate change on the developmental parameters of R. dominica for the period 2041–2070 compared to the period 1970–1997. According to the insect dynamic model, future climate scenarios are expected to induce changes in the development duration, reproduction, and survival rates of R. dominica. The model predicts a (i) 10–15% extension in the development duration, (ii) 20–30% decrease in reproduction, and (iii) 5–10% decrease in survival relative to the historical period. These results underscore the critical importance of implementing adaptive pest management strategies for stored wheat. [ABSTRACT FROM AUTHOR]

The rise in global temperature also favors the multiplication of pests and pathogens, which calls into question global food security. Plants have developed special coping mechanisms since they are sessile and lack an immune system. These mechanisms use a variety of secondary metabolites as weapons to avoid obstacles, adapt to their changing environment, and survive in less-than-ideal circumstances. Plant secondary metabolites include phenolic compounds, alkaloids, glycosides, and terpenoids, which are stored in specialized structures such as latex, trichomes, resin ducts, etc. Secondary metabolites help the plants to be safe from biotic stressors, either by repelling them or attracting their enemies, or exerting toxic effects on them. Modern omics technologies enable the elucidation of the structural and functional properties of these metabolites along with their biosynthesis. A better understanding of the enzymatic regulations and molecular mechanisms aids in the exploitation of secondary metabolites in modern pest management approaches such as biopesticides and integrated pest management. The current review provides an overview of the major plant secondary metabolites that play significant roles in enhancing biotic stress tolerance. It examines their involvement in both indirect and direct defense mechanisms, as well as their storage within plant tissues. Additionally, this review explores the importance of metabolomics approaches in elucidating the significance of secondary metabolites in biotic stress tolerance. The application of metabolic engineering in breeding for biotic stress resistance is discussed, along with the exploitation of secondary metabolites for sustainable pest management. [ABSTRACT FROM AUTHOR]