Wednesday, February 26, 2025

Select corn lines contain compounds that sicken, kill major crop pest

The compounds, called flavonoids, have an insecticidal effect on corn earworm larvae

Penn State

A series of corn plants — image:
The flavonoids that provide insecticide-like protection to some corn lines against corn earworm larvae also provide pigments to the plants that show up in the silks, husks and kernels. Pictured here are the lines used in the research.
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Credit: Penn State

UNIVERSITY PARK, Pa. — The corn earworm causes the loss of more than 76 million bushels of corn in the United States annually, and there is mounting evidence that increasingly extreme weather events and temperatures will exacerbate the damage done to agricultural output by insect pests. Responding to the threat, a team of researchers at Penn State has demonstrated that genetic lines of corn have inherent compounds that serve as insecticides, protecting them from the larvae that feed on them.

In findings recently published online ahead of the March issue of Plant Stress, the researchers reported that corn earworm larvae feeding on the silks, husks and kernels of corn lines containing high levels of flavonoids — chemicals that play essential roles in many biological processes and responses to environmental factors in plants — grow much more slowly and many die, compared to larva feeding on corn lines without flavonoids.

In addition to increased mortality and reduced body weight, larvae feeding on high-flavonoid corn lines developed a leaky-gut-like syndrome, the researchers found, suggesting involvement of microbiome changes in the larval gut. Moreover, the expression of gut health-related genes was changed in larvae consuming the flavonoid-rich husks.

In the study, the researchers compared how corn earworm larvae survived on genetically identical strains, except for a few specific, known differences of corn — in this case, with some expressing high flavonoid content in silks, husks and kernels; some not. The corn, grown at the agronomy farm at Penn State’s Russell E. Larson Agricultural Research Center, included a line engineered to have a gene that triggers flavonoid production and a line that was conventionally bred to produce flavonoids, which was developed over the last two decades by Chopra’s lab from cross-breeding a mutant line of corn.

Researchers pointed out that they noticed “a stark difference” in mortality and bodyweight between corn earworm larvae feeding on flavonoid-overproducing lines as compared to control lines. Both the genetically engineered line and the line bred from the mutant had similar effects on the larvae.

“This research is important because it may be an early step toward the development of corn lines resistant to insect pests ideal for organic production,” said research team leader Surinder Chopra, professor of maize genetics. “These findings, which suggest a novel option for integrated pest management for corn earworm larvae, shows that high-flavonoid maize has the potential to be used in a breeding program to develop specialty corn lines tolerant of multiple insect pests.”

More research is needed before plant breeders could be expected to try developing flavonoid-producing corn lines that also protect against other insects for organic farmers, Chopra noted.

“Future studies will investigate the mechanisms behind flavonoid-mediated damage to the gut of corn earworm larvae and will explore the broader impacts of flavonoid content on plant-insect interactions,” he said.

The study was spearheaded by Debamalya Chatterjee, a former postdoctoral scholar in the Chopra lab who is currently an assistant professor at Skidmore College. Contributing to the research were Charles Colvin, undergraduate researcher in plant science; Tyler Lesko, doctoral student in the Department of Plant Science; Michelle Peiffer, research support assistant and lab manager in the Department of Entomology; and Gary Felton, professor and head of the Department of Entomology.

The U.S. Department of Agriculture’s National Institute of Food and Agriculture financially supported this work.

Journal

Plant Stress

DOI

10.1016/j.stress.2025.100738

Article Title

Plant defense against insect herbivory: Flavonoid-mediated growth inhibition of Helicoverpa zea

How nitrogen reshapes root system architecture in plants?

Higher Education Press

image:
Image
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Credit: Xiujie LIU, Kai HUANG, Chengcai CHU

In soil, nitrogen (N), an essential macronutrient for plant growth, exhibits significant spatial heterogeneity. This necessitates plants to grapple with a complex array of environmental conditions in their quest for N sustenance. Roots, as the pivotal organs in N acquisition, manifest a remarkable morphological plasticity, including variations in the length and density of primary roots, lateral roots, and root hairs, in response to the form and content of available N, which is termed N-dependent root system architecture (RSA). For cultivated crops, the cultivation of an ideotype RSA, characterized by sensitive plasticity under diverse N conditions, is paramount for efficient N utilization, curtailment of N fertilizer inputs, and the realization of a green and sustainable agricultural development trajectory. What is the genetic basis of N-dependent RSA? The answers to this question will not only enrich the current understanding of the plants N utilization process, but also provide a treasure trove of genetic resources for targeted genetic modification, aimed at cultivating crops with ideotype RSA.

Prof. Chengcai Chu and his team from South China Agricultural University have systematically summarized the process of genetic basis of N-dependent RSA in Arabidopsis and major crops. Firstly, N sensing and signaling in plants is the fundamental to N-dependent RSA. The extracellular nitrate signal is primarily sensed and transduced into nucleus through the conserved NRT1-NLPs cascade across diverse plant taxa. Furthermore, long-distance N signal transduction between roots and shoots is mainly mediated by cytokinins and polypeptides, ensuring a harmonious interplay between different plant parts. Upon reception, these N signals intricately interact with phytohormones, such as auxin and brassinosteroid, either directly or indirectly influencing their synthesis, sensing, signaling, and distribution within the root system. This intricate hormonal crosstalk ultimately orchestrates the root developmental process in an N-dependent manner, reshaping the root architecture to suit varying N availabilities. While the majority of studies elucidating the genetic basis of N-dependent RSA have been conducted in the model plant Arabidopsis, our understanding of this process in crop plants remains nascent, let alone the implementation of genetic modification for cultivating ideotype RSA in these economically vital species. Fortunately, integration of advanced techniques like X-ray computed tomography and single cell analysis into plants research promises to unravel the genetic mysteries governing N-dependent RSA in crops. With these innovative tools at our disposal, the realization of ideotype RSA in future crop cultivars may soon transition from a distant aspiration to a tangible reality, heralding a new era in precision agriculture and sustainable food production.

This review has been published on the Journal of Frontiers of Agricultural Science and Engineering in 2025, 12(1): 3–15. DOI: 10.15302/J-FASE-2024587.

Journal

Frontiers of Agricultural Science and Engineering

DOI

10.15302/J-FASE-2024587

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

The genetic basis of nitrogen-dependent root system architecture in plants

Influencer marketing can help tourism industry mitigate waste, pollution

The transferability of passion: how green influencers inspire tourists’ green initiative support

Penn State

UNIVERSITY PARK, Pa. — Social media influencers who are passionate about environmental causes can help the tourism industry inspire tourists to engage in pro-environmental behavior to help mitigate waste and pollution, according to a new study from researchers in the Penn State School of Hospitality Management.

The research team found that influencers who are highly passionate about sustainability lifestyles — coined “green influencers” — can increase tourists’ environmental support through social media messaging. The researchers also found that environmental support, or backing waste reduction and wildlife conservation efforts, can be passed along to tourists via social media when influencers display less passion but do convey strong, specific goals.

Led by Penn State Assistant Professor of Hospitality Management Anni Ding, the research team published its findings in the Journal of Sustainable Tourism.

“Green influencers are people who are highly committed and passionate about environmental causes,” Ding said. “Pollution and waste accumulation can lead to environmental damage at tourist destinations. Tourism companies and destinations can leverage green influencers in their marketing efforts to promote environmentally friendly messaging to help prevent this damage.”

To determine a green influencer’s impact on the environmental support of tourists, the researchers completed two experiments with participants recruited via Prolific, a crowdsourcing panel data platform.

In the first experiment, the researchers explored the effects of green influencers’ passion — or intensity of expression — on tourist support for environmental initiatives, using data from 322 survey participants who were randomly assigned to view a set of social media posts depicting a fictional beach cleanup. One set of social media posts conveyed passion-related emotions and used passionate language whereas another set contained a straightforward recap of the cleanup without displays of emotional imagery or terminology. After viewing the posts, participants answered questions about the passion depicted in the posts as well as about their own green self-efficacy, or one’s belief about their own abilities to act in support of the environment.

“We found passion can be passed from the influencer to their followers through social media,” Ding said. “The link between influencer passion and tourists’ environmental support is reinforced by emotional contagion theory, which says emotions can be transmitted from one person to another. As passion can be contagious, influencers who demonstrate their passion and commitment to a green initiative and may see this spill over to their social media followers.”

Ding said the research team also wanted to understand whether influencer marketing could be effective even if the influencers did not display high levels of passion in their social media posts.

In a second experiment, the researchers tested how influencer goal strength and specificity may affect the social media audience in cases of high or low influencer passion. The research team analyzed data from 514 survey participants who were randomly assigned to view fictional social media posts about a beach cleanup with one of four conditions: high passion with high goal specificity, high passion with low goal specificity, low passion with high goal specificity or low passion with low goal specificity.

The research team found that goal specificity can mitigate low influencer passion, as strong, specific goals with calls to action can show that influencers are truly committed to the cause, according to Ding.

“Tourism companies and destinations can leverage green influencers in their marketing, but companies should not only look at the size of their influencers’ following but also focus on what the influencers are passionate about,” Ding said. “That can ultimately help businesses align their objectives with influencers who can best communicate key message points.”

Ding said partnering with the wrong influencer can be costly for companies because the company would not be efficiently spending their marketing budget if an influencer were not aligned with the company’s goals.

Influencers and their social media followers that align with a company’s target audience while sharing an authentic passion for environmental initiatives is a best-case scenario, according to Ding.

“Positive emotions like passion can be a very powerful tool in marketing or in communications,” Ding said. “By carefully choosing a passionate ambassador to communicate the right message, tourism companies can build an effective communications campaign.”

Tiffany S. Legendre of the University of Houston and Harold S. Lee and Jihye “Ellie” Min of the University of North Texas collaborated on this research.

Journal

Journal of Sustainable Tourism

DOI

10.1080/09669582.2024.2438245

Method of Research

Survey

Subject of Research

People

Article Title

The transferability of passion: how green influencers inspire tourists’ green initiative support

TOO LATE FOR USAID

Better poverty mapping: New machine-learning approach targets aid more effectively

Microlevel structural poverty estimates for southern and eastern Africa

Cornell University

ITHACA, N.Y. – Leveraging national surveys, big data, and machine learning, Cornell University researchers have developed a new approach to mapping poverty that could help policymakers and NGOs better identify the neediest populations in poor countries and allocate resources more effectively.

To eliminate extreme poverty, defined as surviving on less than $2.15 per person per day, governments and development and humanitarian agencies need to know how many people live under that threshold, and where. Yet that information often is lacking in the countries that need help most, the researchers said.

Household surveys on income or consumption – considered the gold standard for defining poverty lines – may be unavailable or outdated because they are expensive and difficult to administer frequently. Meanwhile, data from satellites and other Earth observation systems monitoring infrastructure, natural conditions, and human behavior has been successfully used to generate asset-based poverty indexes disconnected from the monetary measure most relevant to policymakers.

The Cornell team’s new structural poverty estimates seek to address that gap by translating abundant Earth observation data into more actionable terms for policymakers.

Focused on four southern and eastern African nations, the pilot project mapped poverty about as accurately as existing asset index methods, but for more useful measures – including the share of people living below the global poverty line. The structural poverty approach outperformed previous monetary poverty methods and is forward-looking, making it especially useful for informing programming.

“Rapid advances in data science haven’t gained widespread acceptance because they haven’t produced usable estimates,” said Chris Barrett, professor of applied economics and management. “We’ve made computational advances more practical by linking them to monetary poverty lines.”

Barrett is the senior author of “Microlevel Structural Poverty Estimates for Southern and Eastern Africa,” published in Proceedings of the National Academy of Sciences as part of a series of inaugural articles by academy members elected in 2022, including Barrett.

The research focused on Ethiopia, Malawi, Tanzania and Uganda – agricultural nations with high poverty rates where many development agencies are working, but with only a rough idea of where the poorest people live, the researchers said.

“These are places where we think the structural poverty model is quite relevant,” said first author Elizabeth Tennant, a research associate in economics. “They’re also places where we had good data on consumption and assets, so we were able to look at both and model their connections.”

The team trained machine-learning models using 13 national household surveys conducted in the four countries between 2008 and 2020, linking them to Earth observation data on assets like housing quality, land, livestock, vehicles, and access to technology including cell phones. In short, the researchers said, the older survey data trained models to generate localized “nowcasts” of current conditions from recent satellite observations.

“We’re showing that you can get all the computational precision of advances the data science community has made, while having the policy and programming usefulness of these monetary measures – and in a forward-, not backward-looking way,” Barrett said. “You want to know who’s expected to be poor right now – not when a big survey was conducted years ago – and that’s what our structural poverty models help predict.”

The research was funded by the Cornell Atkinson Center for Sustainability and received computing support from the Cornell Center for Social Sciences.

For additional information, read this Cornell Chronicle story.

-30-

Journal

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2410350122

Method of Research

Computational simulation/modeling

Subject of Research

Not applicable

Article Title

Microlevel structural poverty estimates for southern and eastern Africa

Article Publication Date

26-Feb-2025

An emissions tale of two cities: Salt Lake City vs. Los Angeles

Research shows carbon monoxide emissions on Utah freeways worsened while they went down in Southern California

News Release 26-Feb-2025
University of Utah

image:
John Lin, professor of atmospheric sciences, on the roof of the University of Utah's Browning building where a phalanx of air quality monitoring instruments are stationed.
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Credit: Brian Maffly, University of Utah

They may both be Olympic host cities, but Salt Lake City and Los Angeles, the major population hubs of their respective states, are much different places. However, they both experience poor air quality and share valley topography that traps pollutants during weather inversions.

Utah and Southern California differ sharply in their approaches to this problem, with the latter implementing more stringent regulations and fuel standards aimed at reducing emissions from motor vehicles. New research from the University of Utah, in collaboration with University of California scientists, shows California's earlier adoption of stricter rules may have helped lower concentrations of one pollutant—carbon monoxide, or CO—on LA freeways.

“We wanted to see empirically how emission characteristics have changed in these two cities over time,” said co-author John Lin, a Utah professor of atmospheric sciences. The research was initiated by Francesca Hopkins, a professor of climate change and sustainability at UC Riverside, and conducted with colleagues at UC Irvine.

The study relied on measurements taken by mobile labs that drove up and down LA and Salt Lake freeways for a few weeks in the summers of 2013 and 2019, with follow-up data gathering in Los Angeles over the next two summers to observe the effect of the Covid pandemic.

The study especially focused on the ratios of CO to CO2 (carbon dioxide) observed by the mobile labs. These two gasses are co-emitted from fossil fuel combustion and their ratio is an indicator of the efficiency of that combustion, since efficient internal combustion engines would convert Tmore of the fuel to CO2 instead of CO. The more CO emitted relative to CO2, the less efficiently the fuel is being burned.

“The CO-to-CO2 ratios appear to increase in Salt Lake, but they decreased in LA, and of course the question is ‘Why?’” said Lin, who serves as associate director of the U's Wilkes Center for Climate Science & Policy. “What's different between Salt Lake and LA? A lot of things are different. One thing proposed in the paper is the regulation and how much earlier it was adopted in Los Angeles. Salt Lake adopted Tier Three fuel standards not too long after LA but the fuel wasn't available in Utah until 2020.”

Lin offered a caveat arising from a yet-to-be-published study, led by one of his graduate students and based on parallel data gathered by stationary monitoring equipment from the Utah Division of Air Quality housed at Hawthorne Elementary School on 700 East, one of Salt Lake City’s busiest streets about a mile east on Interstate 15. Between 2013 and 2019, CO-to-CO2 ratios recorded at this spot declined.

Breathing carbon monoxide, or CO, impairs the human body’s ability to circulate the oxygen needed for survival. Indoor CO pollution can literally asphyxiate a person. Outdoor concentrations rarely reach such a toxic level, but elevated levels can harm those with heart disease, making it difficult for their organs to get enough oxygen, according to the U.S. Environmental Protection Agency. The agency set the 8-hour threshold for ambient levels of CO at 9 parts per million (ppm), or 35 ppm for 1 hour.

“There are other emissions we could look at, like the ratio of NOx to CO2," Lin said. "Carbon dioxide is the common denominator because it's what you get from burning fossil fuels and, and the engine undergoes ‘clean combustion’, when you convert most of the fuel into CO2 and water. I put clean in quotes because CO2 is a greenhouse gas that leads to climate change”

Motor vehicles are the main anthropogenic source of CO in the atmosphere. Nationally, 38% of anthropogenic CO originates from on-road mobile sources, but that portion is higher for Los Angles and Salt Lake counties, 47% and 56%, respectively, according to the new study.

These metro areas’ transportation fleets are different, with Salt Lake having a higher proportion of trucks, while passenger cars dominate in Los Angeles, and Salt Lake’s cars tend to be older, with a mean age of 9 years. And speed limits are higher in Utah. During the study period, in 2015, Salt Lake City freeway speed limits increased by 5 to 10 mph, which may explain some of the increase in CO emissions.

On the emission control side, California adopted mandates for cleaner vehicles and fuels several years ahead of Utah, as well as offered incentives to drivers to replace their older vehicles. Tellingly, the researchers discovered CO ratios increased in the follow-up testing on LA freeways in the summers of 2020 and 2021 when speeds increased as traffic thinned in the wake of pandemic shutdowns.

#####

The study titled, “Contrasting Summertime Trends in Vehicle Combustion Efficiency in Los Angeles, CA and Salt Lake City, UT,” was published in the Jan. 21 edition of Environmental Science & Technology. University of Utah authors include Susan Bush and former laboratory specialist Ryan Bares, now an environmental scientist with the Utah Division of Air Quality. The lead author is former UC Irvine graduate student Cindy Yañez, who is now with the California Air Resources Board.

Journal

Environmental Science & Technology

DOI

10.1021/acs.est.4c11701

Method of Research

Observational study

Subject of Research

Not applicable

Article Title

Contrasting Summertime Trends in Vehicle Combustion Efficiency inLos Angeles, CA and Salt Lake City, UT

Are our refrigerants safe? The lingering questions about the chemicals keeping us cool

University of New South Wales

Joshua Thompson, a PhD student involved in the research, operates the technology. — image:
A team at UNSW produced a gas mixture at various pressures to simulate the atmosphere and observe the chemical reaction.
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Credit: Photo: Supplied to UNSW

A team of scientists at UNSW has discovered that some of the most important new refrigerants break down, in part, into persistent greenhouse gas pollutants, including compounds that have been banned internationally. Refrigerants are chemicals that turn from a liquid to a gas – and vice-versa – and transfer heat in the process, that are used for refrigeration and indoor heating and cooling. The chemicals are also used as aerosol propellants, fire retardants and in the manufacture of foamed plastics.

Hydrofluoroolefins (HFOs), which react rapidly in the lower atmosphere, have emerged as the lead synthetic chemical for refrigerants, and are considered a more environmentally friendly alternative to their chemical predecessors.

While it’s known that HFOs decompose into chemicals like trifluoroacetaldehyde, there has been persistent discussion about whether this compound further breaks down into fluoroform – the most environmentally damaging hydrofluorocarbon (HFC) they were used to replace.

A paper led by Dr Christopher Hansen from UNSW Chemistry, and published in the Journal of the American Chemical Society, has demonstrated that HFOs do break down into a small amount of fluoroform. This new research suggests we need to more closely examine HFOs’ environmental impact, raising questions about their long-term safety.

“We don’t fully understand the environmental impacts of HFOs at this point,” says Dr Hansen. “But, unlike previous examples such as the CFCs and leaded petrol, we are trying to figure out the consequences of large-scale emission before we’ve potentially harmed the environment and human health in an irreversible way. We're trying to try to change the way that science introduces new products.”

The story so far

The hole in the ozone layer is a result of human activities that have released ozone-depleting chemicals, including chlorofluorocarbons (CFCs) – some of the first synthetic chemicals used as refrigerants and in aerosol cans.

Thanks to The Montreal Protocol, society began phasing these out internationally, and they were largely replaced with HFCs, which were used on a global scale from the mid 90s.

Although HFCs don't cause any ozone layer depletion, they turned out to be potent greenhouse gases. “In the end, scientists discovered that 1kg of fluoroform – a once commonly used HFC – emitted today will contribute to as much to surface heating of the planet over the next century as more than 14,000kg of carbon dioxide,” says Dr Hansen.

After realising the extreme greenhouse warming potential of HFCs, their global phaseout began in 2016.

HFOs, which have a shorter atmospheric lifetime, are now the leading synthetic replacements and are being rapidly proliferated as refrigerants, foam-blowing agents – such as those used in insulating foam – and aerosol propellants.

While scientists know some information about the chemical pathways of HFO decomposition, there has been a longstanding debate about whether they actually break down into some of the most environmentally unfriendly HFCs.

Experiments simulating the atmosphere

HFOs are made up of chemical units that are more reactive than their previous counterparts, so they don’t rise to the upper atmosphere and become long-lived greenhouse gases.

“But as chemists, we look at the structures of these molecules and we start to try and imagine what they are turned into,” says Dr Hansen. “So rather than just go, oh, this thing only has a lifetime of two weeks, it can't be a greenhouse gas, we must see what it's turned into.

“And most chemists will look at these structures, and they can draw reactions that actually lead to HFCs.”

But confirming whether HFOs break down into HFCs in low yields requires difficult experiments and most existing techniques and instruments lack the sensitivity and specificity to do so.

Dr Hansen and his team used multiple techniques, including two invented just for this study, to measure and evaluate the chemical reaction across the full range of pressures expected in the atmosphere.

“We used a variety of spectroscopic techniques to observe the reaction. And we made up a gas mixture at various pressures to simulate an atmosphere polluted with a trace amount of the immediate HFO decomposition product. Then we used a laser to simulate the photons that would otherwise come from the sun, to drive the reaction,” says Dr Hansen.

New data for climate models

We know that HFOs decompose into fluorinated carbonyls such as trifluoroacetaldehyde at a yield up to, or greater than, 100%. This means all the molecules of HFO turn into the first product and, for some HFOs, you might get two molecules of that product for each molecule of HFO that breaks down. This study reveals that the next step of the reaction, driven by light, produces a small amount of fluoroform from the decomposition of trifluoroacetaldehyde. Fluoroform is the HFC with the greatest global warming potential.

“We have demonstrated comprehensively that some of the most important HFOs do break down into HFCs and have provided the first hard scientific data needed to model and predict the consequences of large-scale emission,” says Dr Hansen. “Although the reaction only produces a small amount of fluoroform, the chemical can exist in the atmosphere for up to 200 years, and with a global warming potential more than 14000 times greater than CO2, a small yield can still have a significant impact.”

Many atmospheric crises have caught us by surprise. “Think leaded petrol, lethal smog events of the 20th century, the ozone hole crisis,” Dr Hansen explains. “But this wasn’t because our models were not good enough, but rather because the important chemistry was missing from the models,” he says.

Now, this study settles a longstanding controversy and provides the hard, scientific data needed to model and predict the impact of large-scale emission of HFOs, before policymakers may need to react to an emerging environmental crisis.

Climate modelling groups at UNSW, as well as scientists around the world, are now ready to input this data into models, to help work out the environmental impact of continuing to use HFOs.

“Although questions remain, this paper offers crucial evidence that should inform the next steps in addressing the environmental impact of the chemicals we release into the atmosphere,” Dr Hansen says.

Dr Hansen and his team are planning further novel experimental work. “For this paper, we performed the experiments at a single wavelength, the wavelength used in studies that are presently guiding regulators, industry, governments,” he says. “We plan to study this chemistry using other wavelengths of light, where the yield could be higher or lower.”

Journal

Journal of the American Chemical Society

DOI

10.1021/jacs.4c11776

Method of Research

Computational simulation/modeling

Subject of Research

Not applicable

Article Title

Fluoroform (CHF3) Production from CF3CHO Photolysis and Implications for the Decomposition of Hydrofluoroolefins and Hydrochlorofluoroolefins in the Atmosphere

Investors in farm equipment maker Deere reject anti-DEI resolution

By Ross Kerber and Utkarsh Shetti

(Reuters) - Deere investors voted overwhelmingly against a resolution aimed at its diversity, equity and inclusion efforts on Wednesday, continuing a pattern of shareholder distaste for anti-DEI measures despite Republican political pressure on executives.

During a webcast of its annual meeting, executives with the farm equipment maker said only 1.3% of votes cast were in support of a resolution calling on the company to report on racial and gender hiring statistics "to prove it does not practice discrimination."

The resolution was filed by the National Legal and Policy Center, a conservative-leaning Washington think tank that has opposed many corporate diversity efforts. Two other resolutions aimed at restricting social action by Deere won similarly low levels of support.

Deere's meeting was closely watched because in July it became one of the first major U.S. companies to back away from supporting programs such as LGBTQ+ pride events.

Numerous other U.S. companies have retreated from DEI in recent months, particularly as the Trump administration has stepped up threats to companies and institutions that engage in those efforts.

But many investors and executives see DEI efforts as necessary to address underrepresentation of certain populations in management roles. On Tuesday, Apple investors voted in defense of the company's DEI policies, as did Costco investors in January.

(Reporting by Ross Kerber; Editing by Rod Nickel)