Foundational and Translational Research Opportunities to Improve Plant Health

Abstract

Summary This whitepaper reports the deliberations of a workshop focused on biotic challenges to plant health held in Washington, D.C. in September 2016. Ensuring health of food plants is critical to maintaining the quality and productivity of crops and for sustenance of the rapidly growing human population. There is a close linkage between food security and societal stability; however, global food security is threatened by the vulnerability of our agricultural systems to numerous pests, pathogens, weeds, and environmental stresses. These threats are aggravated by climate change, the globalization of agriculture, and an over-reliance on non-sustainable inputs. New analytical and computational technologies are providing unprecedented resolution at a variety of molecular, cellular, organismal, and population scales for crop plants as well as pathogens, pests, beneficial microbes, and weeds. It is now possible to both characterize useful or deleterious variation as well as precisely manipulate it. Data-driven, informed decisions based on knowledge of the variation of biotic challenges and of natural and synthetic variation in crop plants will enable deployment of durable interventions throughout the world. These should be integral, dynamic components of agricultural strategies for sustainable agriculture.

Lessons in effector and NLR biology of plant-microbe systems

“…We cannot underestimate the potential of translating fundamental knowledge, such as the concepts discussed in this paper, into practical applications that can solve real-world agricultural problems (Alfred et al 2014;Kamoun 2014;Michelmore et al 2017). There is a sense that as the science of plant-microbe interactions continues to mature and coalesce around robust principles, opportunities for practical applications are accelerating (see Supplementary Table S1 in Michelmore et al 2017).…”

An oomycete RXLR effector triggers antagonistic plant hormone crosstalk to suppress host immunity

“…This is best exemplified by co-option of JA-SA antagonistic cross talk: while this antagonism provides the plant with capacity for optimal defence, this configuration also carries a vulnerability, because pathogens/pests can activate one sector to suppress the other (Gutjahr & Paszkowski, 2009; Zhang et al, 2017). Understanding the mechanisms underpinning this co-option, across pathogen taxa, comprises an important piece in the puzzle of how microbes and pests successfully exploit host plants (Michelmore et al, 2017). In this report, we provide evidence for a novel mechanism through which an oomycete can manipulate JA-SA antagonism: HaRxL10 is secreted by Hpa into Arabidopsis cells, wherein it traffics to the nucleus and directly engages the JAZ3 transcriptional repressor protein to directly or indirectly trigger its degradation by the 26S proteasome.…”

Constant vigilance: plant functions guarded by resistance proteins

“…Deeper insights into the layers of plant functions that are targets of pathogens should allow the design of engineered resistance specificities protecting different cellular compartments and biochemical or physiological functions. Such a distributed network of resistance will be much harder for a pathogen to overcome, as it would entail the simultaneous evolution of several evasion strategies (Michelmore et al, 2017). In addition, such engineering approaches will likely have to include a better understanding of regulatory mechanisms that keep the plant immune system in check to prevent yield penalties.…”