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Survival in desert ecosystems poses significant challenges for plants due to harsh conditions. Plant microbiomes are thought to promote resilience; however, whether plant hormones, specifically strigolactones (SLs) and karrikins (KARs), shape plant microbiomes remains unknown. The recruitment of root-associated microbiomes in Nicotiana attenuata, a model desert plant, silenced in specific genes associated with SL biosynthesis (CCD7) and perception (D14), karrikin perception (KAI2), and in the shared receptor (MAX2), required for both pathways, was studied. SL and KAR signaling, with MAX2 as a co-regulator, fine-tuned the assembly of root-associated microbiomes, with unique and shared regulatory functions on bacterial microbiome recruitment, particularly in taproot. Significant variation among the different plant genotypes in bacterial diversity and composition in taproot and lateral roots provides a foundation for future research to explore how microbiomes function in plant resilience in these harsh environments. [ABSTRACT FROM AUTHOR]

Feeding and oviposition by phytophagous insects are both known to trigger defenses in plants. Whether these two defenses functionally interact remains poorly studied, although these interactions are likely important for pests with overlapping generations. Here we investigated the differences and interaction between feeding- and oviposition-induced plant defenses triggered by the brown planthopper (BPH, Nilaparvata lugens), which gregariously feeds and oviposits on rice. Analyses of host-plant transcriptomes, phytohormones, and direct and indirect defense compounds all show that BPH gravid females (GFs), but not nymphs and non-gravid females (NFs), strongly induce rice defenses. BPH nymphs and GFs prefer to feed on plants previously infested by nymphs over un-attacked plants, but are repelled by plants previously infested by GFs. Moreover, nymph feeding is found to reduce the attractiveness of rice plants to natural enemies and decrease egg parasitism by suppressing GF-induced volatiles that mediate indirect defenses in both growth chambers and paddies. Intergenerational interactions between oviposition- and feeding-induced plant defenses not only promote the development of the population of pest insects but may also contribute to the aggregation behavior of pest insects by suppressing oviposition-induced indirect plant defenses., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)