BARD team recently met with scientists leading BARD-supported projects to hear firsthand about their discoveries, ideas, and the international collaboration. These visits provide a unique opportunity for researchers to share real experiences of teamwork, its successes, lessons, and human stories. During a recent visit to ARO, the BARD team observed five joint research projects addressing key agricultural and environmental challenges.
Topics included honeybee virus resistance through bee hygienic behavior, sustainable dairy nutrition aligned with environmental goals, Clavibacter host specificity and resistance in eggplants, drought-tolerant wheat through root-associated microbiomes, and extended tomato shelf life via autophagy mechanism.
The visits offered valuable insights into project progress and strengthened personal and professional ties, highlighting the importance of in-person engagement for advancing real-world impact. Each encounter deepens understanding and reinforces the network of innovators shaping a more sustainable agricultural future.
Prof. Victoria Soroker, Institute of Plant Protection:
Honey Bee Hygienic Behavior – Curtails or Enhances Virus Transmission
As a social insect living in colonies, bees have several behavioral and defense strategies. First, they possess an personal immune system that combats pathogens. Second is their social behavioral and hygienic system, which is primarily active against parasites. In the latter, bees identify and remove sick or dead larvae from the colony, which is proving effective against several diseases and the Varroa mite, although its efficacy against viruses has yet to be confirmed.
The research team led by Dr. Victoria Soroker from the Volcani Institute in Israel, along with Professors Marla Spivak and Declan Schroeder from the University of Minnesota, is conducting research examining the link between the hygienic behavior of honeybees and the spread of viruses in hives through comparing hives with high and low hygiene levels.
Using advanced artificial insemination techniques, the researchers are breeding hives with different hygiene levels in order to examine several key aspects. The research is still ongoing, but it appears that virus-infected bee larvae emit different odors compared to healthy larvae, and that nurse bees from hygienic hives also have a stronger personal immune system, although its effectiveness against viruses is still being tested. Additionally, the two research laboratories (in the U.S. and Israel) show significant differences in viral infection rates, which may add further significance to the findings.
This research could provide insights into the natural defense mechanisms of honeybees against viral pathogens and open new pathways for improving bee health and preserving their populations.
Dr. Yehoshav Ben Meir, Institute of Animal Sciences:
Manipulating dietary sodium and anions to reduce the environmental impacts of dairy cattle: sodium excretion and ammonia emission from manure.
Nutritional Strategies to Reduce Dairy Farming’s Environmental Impact
The dairy industry is a cornerstone of both local and global economies, providing essential nutrition and supporting rural livelihoods around the world. Yet, despite its benefits, public concern continues to grow over its environmental footprint, particularly regarding soil, water, and air quality. Addressing these concerns is critical for advancing sustainable agriculture. The collaborative research project between teams in Israel and the United States is tackling this challenge head-on. The research project focuses on developing nutritional strategies that reduce two major environmental pollutants from dairy farms: sodium (Na) effluents and ammonia (NH₃) emissions from manure. Sodium runoff can degrade soil and contaminate groundwater, while ammonia emissions not only diminish the value of manure as fertilizer but also contribute to air and water pollution, unpleasant odors, and respiratory health risks for both animals and humans.
The project’s dual objectives are to reduce dietary sodium in lactating cows to minimize sodium excretion, and to increase dietary chloride or sulfur to lower ammonia emissions. Through four carefully designed experiments, the researchers aim to understand how these dietary changes affect cow productivity, nutrient digestibility, and environmental outputs. The experiments are conducted jointly in Israel and the U.S. with each team contributing specialized expertise: the Israeli team focuses on mineral analysis, and the U.S. team, led by Prof. Chanhee Lee from Ohio State University, leads ammonia emission measurements.
The final experiment will integrate findings from the earlier studies to test a combined dietary approach that simultaneously reduces sodium and ammonia outputs.
Dr. Sigal Miyara Brown, Institute of Plant Protection:
Targeting Core RxLR-like effectors of phytonematodes to control root knot nematode disease
Advancing Research on Root-Knot Nematode Effectors
Plant-parasitic nematodes (PPNs) of the genus Meloidogyne, commonly known as root-knot nematodes (RKNs), represent one of the most destructive pests in global agriculture. These parasites manipulate host root cells, reprogramming them into specialized feeding cells that sustain nematode development and reproduction. Central to this process are molecular effectors secreted from the nematode’s salivary glands and injected into plant cells, enabling invasion, suppression of host defenses, and cellular reprogramming.
While comparative genomics has been widely used to predict candidate effectors, current pipelines generate thousands of secreted proteins, many of which are unrelated to parasitism, while overlooking unconventionally secreted effectors. To address this gap, the research project let by Dr. Miyara Brown offers a refined approach that leverages the discovery of an RxLR-like motif, previously associated with oomycetes, identified in Meloidogyne javanica genes, including known effectors. This motif may prove critical for effector uptake into host cells, and thus provides a promising marker for effector discovery.
The project has three main objectives. First, computational prediction of RxLR-like effectors using bioinformatics and machine learning. Second, functional characterization of candidate effectors through experimental validation. And third, identification of plant host targets that could be modified to enhance resistance.
Dr. Doron Teper, Institute of Plant Protection, and Prof. Gitta Coaker of UC Davis:
Effector proteases from Clavibacter: identification of plant immune receptors and investigating their influence on host specificity in Solanaceae
Uncovering Host Specificity in Clavibacter Plant Pathogens
Clavibacter, a genus of actinomycete plant pathogenic bacteria, continues to pose a serious threat to key agricultural industries, including tomato, potato, and maize. Despite its impact, the mechanisms behind its pathogenicity, host immune responses, and host specificity remain largely unexplored. Currently, no commercial Solanaceous crop varieties show resistance to Clavibacter, and no resistance loci have been identified in any crop.
Recent research highlights the role of secreted serine protease effectors from the Pat-1 family in Clavibacter species. These effectors significantly influence pathogenicity, yet their plant targets and mode of action are still unknown. The research team identified Pat-1 and ChpG, effectors from Clavibacter michiganensis, the causal agent of bacterial canker in tomato, as key players in determining host specificity. Pat-1 affects Nicotiana tabacum, while ChpG targets eggplant.
Through bacterial growth and immune response assays, the research team have observed that certain plant genotypes recognize these effectors. Thus, effectively rendering them non-hosts to Clavibacter. This led the team to hypothesize that Pat-1 effectors serve a dual role: promoting virulence in susceptible plants, while triggering immune responses in resistant ones.
To deepen their understanding, they apply transcriptional, comparative genomic, and genetic approaches to investigate the physiological functions of Pat-1 proteases. The goal is to clarify their role in host specificity and identify immune receptors that recognize these effectors in resistant plants.
This research advances the knowledge of plant-pathogen interactions and paves the way for developing crops with resistance to Clavibacter diseases.
Dr. Dror Minz, Institute of Soil, Water and Environmental Sciences, with Dr. Roi Ben David from ARO, Prof. Itzhak Hadar from Hebrew University, and Prof. Stefan Green Rush University:
Short term drought-tolerance inducing rhizobacteria (STDiR): a potential for water stress amelioration in wheat
Exploring Wild Wheat Microbiomes to Improve Drought Tolerance in Domesticated Crops
In regions where rain-fed wheat is cultivated, such as Israel and large parts of the United States, rainfall during the growing season is highly unpredictable. This variability poses a significant challenge to wheat production. After the initial rains, wheat seedlings typically emerge within two weeks, provided soil moisture is adequate. However, when rainfall halts unexpectedly, seedlings can suffer damage, leading to reduced yields. With climate change intensifying, such dry spells are expected to become more frequent and severe.
To address this challenge, researchers are turning to the evolutionary resilience of wild wheat relatives, such as Triticum dicoccoides and Aegilops peregrina. These species, along with their co-evolved rhizosphere microbiomes, have adapted over millions of years to thrive in drought-prone environments. In this project , researchers hypothesized that these microbiomes harbor beneficial bacteria with genetic traits that promote plant drought tolerance, traits that may have been lost during the domestication of modern wheat.
The study aims to investigate the structure and function of rhizosphere microbiomes associated with these wild wheat species. By identifying microbial communities that enhance drought tolerance in young wheat seedlings, the research team hopes to isolate and apply what they call “Short-term Drought-Tolerance Inducing Rhizobacteria” (SDTiR).
To achieve this, rhizosphere soil samples were collected from T. dicoccoides and A. peregrina across ten locations along a rainfall gradient in Israel. These samples were tested for their ability to confer short-term drought resilience when applied to domesticated wheat seedlings. Promising microbial communities are being analyzed using advanced molecular techniques, including quantitative PCR, long-read 16S rRNA gene sequencing, and high-throughput shotgun metagenomics. These methods help identify both known and novel bacterial traits linked to drought tolerance. In addition to characterizing these communities, the team is working on isolating individual SDTiR strains and evaluating their effectiveness in planta.
Dr. Minz: “Our ultimate goal is to develop a predictive model based on metagenomic and genomic data to pinpoint key traits responsible for short-term drought resilience. If successful, SDTiR strains, either individually or as part of synthetic microbial consortia, could be developed into seed treatments for commercial wheat varieties.”
Dr. Simon Michaeli, Institute of Postharvest and Food Sciences:
Regulating Ripening and Chilling Tolerance of Tomato Fruits Through Autophagy Modulat
Exploring Autophagy’s Role in Tomato Ripening and Chilling Tolerance
Fruit ripening and stress tolerance play a critical role in global food security, and their modulation contributes directly to sustainable agricultural practices. Tomato, a key crop worldwide, serves as a model system for studying fleshy fruit ripening and stress responses.
Ripening in tomato is governed by a complex interplay of phytohormones, transcription factors, and epigenetic mechanisms. This process involves extensive biochemical reprogramming, initially driving biomass accumulation, and later triggering tissue softening, color transformation, breakdown of toxic defense compounds, volatile production, and the synthesis of soluble sugars. These changes require substantial remodeling of cellular content, with precise regulation of synthesis and degradation pathways throughout each stage of ripening.
One of the major degradation mechanisms in eukaryotic cells is macroautophagy, commonly referred to as autophagy. This process involves the formation of a double-membrane structure, the autophagosome, which encloses cytosolic cargo destined for degradation in the vacuole.
Preliminary research utilizing autophagy inhibitors, analysis of tomato autophagy-related proteins SlATG8 and SlATG5, and confocal microscopy reveals that autophagy is active during fruit ripening and is essential for its proper progression. Furthermore, autophagy activity increases during cold storage, indicating a potential role in enhancing chilling tolerance.
The research, originally led by the late Dr. Autar Matto of USDA ARS and Dr. Simon Michaeli, aims to further elucidate the role of autophagy in tomato fruit ripening and chilling tolerance, and to assess the impact of its modulation on these traits. Prof. Barbara Blanco-Ulate from UC Davis joined the project after the passing of Dr. Matto.
Two complementary approaches are being employed:
Application of Natural Autophagy Inducers: Researchers are testing eco-friendly and health-promoting compounds such as the polyamines spermine and spermidine, and the sugar trehalose. These molecules are known to activate autophagy in animals, promoting longevity and health-span, though their effects in plants remain unexplored.
Genetic Induction of Autophagy: Overexpression of ATG5 and ATG7, two rate-limiting proteins essential for autophagy, is being used to stimulate the pathway.
Following autophagy activation through both approaches, the team is evaluating fruit shelf life, ripening progression, chilling tolerance, and overall quality. This research holds promise for advancing sustainable agriculture and improving postharvest fruit resilience.
