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Hedgerows Aid in Pest Control

hedgerows

Research has shown that hedgerows of native California flowering shrubs planted along the edge of a crop field help keep crop pests under control by increasing the activity of natural enemies. UC Agriculture and Natural Resources and UC Berkeley researchers analyzing hedgerows in Yolo County have found that not only are farmers diversifying their land by planting hedgerows, but those plantings are attracting natural enemies that provide economic benefits. The two-year study of hedgerows planted adjacent to processing tomatoes showed higher numbers of natural enemies such as lady beetles (aka lady bugs) and fewer crop pests compared with conventionally managed field crops edged with residual weeds.

Benefits from Hedgerows Extend into Field

The researchers discovered that the increase in natural enemy activity in the hedgerows extended 600 feet into adjacent tomato crops and resulted in a reduction of aphid pests and an increase in stink bug egg predation by parasitoid wasps. Tomato fields adjacent to a hedgerow required fewer pesticide treatments than the tomato fields without hedgerows.

This report appears in the November 2015 issue of Acres U.S.A.

Bats a Boon to Corn Farmers

lasiurusborealis

Corn farmers, look to the sky at dusk and mutter thanks to the bats swooping over your moth-ridden fields: Those winged mammals put more than $1 billion back into your collective pockets, a new study suggests.

The first-of-its-kind research used nets to fully enclose 20-by-20-meter fragments of large corn fields at night, thereby excluding foraging bats throughout the growing seasons in southern Illinois in 2013 and 2014.

The team’s analysis focused on damage caused by corn earworms, the crop-damaging larvae of a species of moth (Helicoverpa zea) that lives worldwide and is often preyed upon by bats such as North America’s eastern red bat (Lasiurus borealis). Ears grown where bats couldn’t feed on moths had 56 percent more larvae-damaged kernels, the researchers report in the Proceedings of the National Academy of Sciences.

On the whole, bats increased crop yield by 1.4 percent — a benefit that, on average and at current corn prices, adds up to a difference of about $3.18 per acre and more than $1 billion worldwide.

The drop in damage could be attributed to bats, the researchers say, because the crop-enclosing nets were rolled up during daylight hours to provide access for farmers and pest-eating birds.

This article appears in the November 2015 issue of Acres U.S.A.

Book review: Altered Genes, Twisted Truth: How the Venture to Genetically Engineer Our Food Has Subverted Science, Corrupted Government, and Systematically Deceived the Public

Altered Genes, Twisted Truth Book Review

Altered Genes, Twisted Truth by Steven Druker

by Steven Druker, review by Simi Summer, Ph.D.

Safe food activists and concerned consumers alike will not want to miss the newest entry into the GM food debate by public interest attorney Steven Druker. Endorsed by Dame Jane Goodall, UN Messenger of Peace, the book has been launched at a critical time in the history of national and global food production.

Unwanted trends in the name of “sustainable agriculture” and international agricultural development point to the success of the Green Revolution in deceiving innocent farmers through biotechnology. This includes the widespread distribution of GM seeds to “solve” world hunger. Likewise, many countries with strict labeling laws, that have banned GMOs, are now considering commercial planting of GM crops. This reflects a change in collective thinking which seriously challenges international GM blockades currently in place. On the home front, the Safe and Accurate Food Labeling Act, otherwise known as the Dark Act, has been making headway, while GMO labeling supporters are busy letting congress know that this is not the kind of legislation they want implemented.

Although Druker’s book addresses the most current food safety concerns in an indirect manner, his topic is timely. He offers a compelling historical exposé of the way in which both the government and leading scientific bodies have convincingly misrepresented the facts about biotechnology. Druker claims that when GMO crops were first approved for commercial use in 1992, the government covered up and ignored the warnings of their own scientists, lied about the facts and subsequently violated federal food safety law by allowing these foods to be sold and marketed without using standard testing to prove that they were safe. Continue Reading →

Silicon’s Role in Rice Production

rice-fieldSilicon (Si) is the second most abundant element of the Earth’s crust after oxygen. It has long been neglected by ecologists, as it is not considered an essential nutrient for plants. However, research in recent years shows that it is beneficial for the growth of many plants, including important crops such as rice, wheat and barley.

For instance, Si enhanced the resistance against pests, pathogens and abiotic stresses such as salts, drought and storms. Silicon might, thus, play a crucial role in the development of sustainable rice production systems with lower or zero input of harmful pesticides.

Researchers from the interdisciplinary LEGATO project on sustainable rice production looked in more detail at the cycle of plant-available Si in contrasting regions of Vietnam and the Philippines to provide insights on the importance of this element in rice production.

An article published in the journal Plant and Soil reports on Si cycling and budgets on the farm level in the Laguna province of the Philippines. The data shows that the irrigation water can provide a considerable amount of the Si that is taken up by plants. In rainwater, the concentrations of Si were below the detection limit of the analytical method; the researchers, thus, assume that rain is not an important Si source for plants. Another major source of plant-available Si is the dissolution of solid soil particles. Continue Reading →

Book Review: Chasing the Red Queen ─ The Evolutionary Race Between Agricultural Pests and Poisons

Chasing the Red Queenby Andy Dyer, reviewed by Chris Walters

It’s not often that satirical fiction offers a nearly perfect illustration of a scientific principle. Yet Lewis Carroll pulled it off in Through the Looking-Glass when Alice mentions to the Red Queen that running fast generally gets you someplace, at least in Alice’s experience.

“‘A slow sort of country!’ said the Queen. ‘Now, here, you see, it takes all of the running you can do to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!’”

For a while, as Andy Dyer tells it, agricultural chemistry — pesticides and herbicides — were able to run fast enough to produce earth-shaking results. Their success transformed the fundamental human activity of growing food. Then they fell behind, finally leading to GMOs and the rapid adaptations of pests targeted by biotech cultivars, a turn of events Dyer calls “utterly predictable.” When you’re talking about the evolutionary biology of crops, weeds and insects, you’re describing a zone where the Red Queen rules. Continue Reading →

Natural Plant Toxins Aid Bees

Bee1webResearchers studying the interaction between plants, pollinators and parasites report that in recent experiments, bees infected with a common intestinal parasite had reduced parasite levels in their guts after seven days if the bees also consumed natural toxins present in plant nectar.

In this early and most comprehensive study of its kind, researchers at the University of Massachusetts Amherst and Dartmouth College studied hundreds of eastern bumblebees, Bombus impatiens, and their intestinal parasite Crithidia bombi, using eight separate toxic chemicals, known as secondary metabolites, produced by plants to protect themselves against predators.

The eight chemicals studied were nicotine and anabasine found in the nectar of flowers in the tobacco family, caffeine from coffee and citrus nectar, amygdalin from almond nectar, aucubin and catalpol from turtlehead flowers, gallic acid from buckwheat nectar and thymol from basswood tree nectar.

They found that these chemicals in nectar reduced infection levels of the common bumblebee parasite by as much as 81 percent by seven days after infection.

UMass Amherst evolutionary ecologist Lynn Adler said, “We found that eating some of these compounds reduced pathogen load in the bumblebee’s gut, which not only may help the individual bees, but likely reduced the pathogen Crithidia spore load in their feces, which in turn should lead to a lower likelihood of transmitting the disease to other bees.”

She adds, “Because plants just sit there and can’t run away from things that want to eat them, they have evolved to be amazing chemists. They make biological compounds called secondary metabolites, which are chemicals not involved in growth or reproduction, to protect themselves. They are amazing in the diversity of what they can produce for protecting themselves or for attracting pollinators.”

Adler says results may have implications for growers who depend on pollinators, who may want to think about planting pollinator-friendly hedgerows and gardens containing plants that produce natural herbal remedies for some of the common parasites and diseases that ail bees and other pollinating insects.

“The more we look, the more we see that these compounds are in nectar and pollen too,” she adds. “With so many people looking at bee health these days, it’s taken a long time for us to realize that perhaps we should be paying attention to how floral secondary compounds mediate pollinator dynamics and their interactions with pathogens. Having bees consume these protective chemicals could be a natural treatment of the future.”

Commercial honeybee growers already use one such chemical, thymol, found in thyme plants, to treat mite infestations.

Findings appear in Proceedings of the Royal Society B.

This article appears in the April 2015 issue of Acres U.S.A.