Emerging strategies for precision microbiome management in diverse agroecosystems.

Substantial efforts to characterize the structural and functional diversity of soil, plant and insect-associated microbial communities have illuminated the complex interacting domains of crop-associated microbiomes that contribute to agroecosystem health. As a result, plant-associated microorganisms have emerged as an untapped resource for combating challenges to agricultural sustainability. However, despite growing interest in maximizing microbial functions for crop production, resource efficiency and stress resistance, research has struggled to harness the beneficial properties of agricultural microbiomes to improve crop performance. Here, we introduce the historical arc of agricultural microbiome research, highlighting current progress and emerging strategies for intentional microbiome manipulation to enhance crop performance and sustainability. We synthesize current practices and limitations to managing agricultural microbiomes and identify key knowledge gaps in our understanding of microbe-assisted crop production. Finally, we propose research priorities that embrace a holistic view of crop microbiomes for achieving precision microbiome management that is tailored, predictive and integrative in diverse agricultural systems.

A role for the gibberellin pathway in biochar-mediated growth promotion.

Biochar is a carbon negative soil amendment that can promote crop growth. However, the effects of biochar on different plant species and cultivars within a species are not well understood, nor is the underlying basis of biochar-mediated plant growth promotion. This knowledge is critical for optimal use of biochar and for breeding biochar-responsive plants. Here, we investigated the genotype-specific effects of biochar on two cultivars of Solanum lycopersicum (tomato), and two wild relatives of tomato, Solanum pimpinellifolium, and Solanum pennelli, in two types of biochar. Biochar promoted shoot growth in all genotypes independent of biochar type but had genotype-dependent effects on other plant traits. Germination tests, exogenous GA4 application and mutant analysis indicated a role for GA in biochar-mediated plant growth promotion. Together, our results suggest that biochar promotes growth partially through stimulation of the GA pathway.