Month: June 2023

Entomology Today 10 hours ago Leave a Comment

Responsible use of pesticides depends in part on understanding where and when they’re used and their impacts on the environment. However, a key source of information on pesticide usage is being scaled back, which could leave scientists and the public in the dark. Just one example of research using data from the U.S. Geological Survey Pesticide National Synthesis Project is a 2023 study linking population declines in the bumble bee Bombus occidentalis to usage of neonicotinoid pesticides. (Photo by Casey Delphia, Ph.D., Montana State University)

By Maggie Douglas, Ph.D.

Imagine public health workers trying to manage the spread of disease without information on where infection rates are highest or how they are changing week-to-week. Or scientists and policymakers attempting to understand and mitigate climate change without monitoring the concentration of greenhouse gases in the atmosphere. This specter is all too real for those of us studying and managing pesticide use and its effects, who are facing the slow disappearance of a critical resource: the U.S. Geological Survey Pesticide National Synthesis Project.

For over a decade, this USGS program has published datasets, maps, and graphs describing the use of agricultural pesticides in U.S. states and counties on an annual basis back to 1992. At its most complete, the dataset reported hundreds of chemicals spanning pest targets (insecticides, fungicides, and herbicides) and covering virtually all U.S. cropland, making it the single most comprehensive description in the country of which pesticides are applied where and when. Even if you aren’t familiar with the name of the project, you may have seen one of their now-ubiquitous maps or graphs, which are frequently used in news stories.

However, in recent years, this invaluable resource has been reduced in size, scope, and detail, and more cuts are looming. Scientists in a variety of fields, including entomology, are concerned.

Pesticide Data is a Public Good

Basic information on pesticide use patterns is easy to take for granted, yet it is essential to sound science and policymaking on a diverse array of topics, including integrated pest management (IPM), wildlife conservation, water quality, and human health. The USGS Pesticide National Synthesis Project data have been used to understand how fungicides affect soybean yield and how spatial patterns of pesticide use lead to the evolution of resistance. It has been used to show that insecticide use is becoming less toxic to vertebrates like humans but more toxic to insects and other invertebrates. And it has facilitated ‘scaling up’ pollinator research, helping scientists identify which pesticides are associated with reduced crop pollination and bumble bee declines. In human health, researchers recently used the USGS data to link particular fumigants with pediatric and total cancer incidence in the western U.S. and to understand the implications of farmland fungicide use for treatment-resistant fungal disease. The deep scientific value of the dataset explains why more than 250 scientists recently signed a letter expressing their concern that it may be further diminished or lost entirely.

The USGS program has also become a central resource for education, outreach, and agricultural extension related to pesticides. More than a hundred organizations working on issues ranging from insect conservation to IPM to farmworker health recently signed a letter expressing their dismay about the degradation of the program, which they described as “one of the most vital tools for monitoring pesticide use and estimating water pollution nationwide.” The Entomological Society of America, meanwhile, has been in contact with Congress, federal agencies, and other societies regarding the issue.

The maps and graphs published by the USGS are frequently used in a wide array of venues to demonstrate how pesticide use varies in space and time. As just one example, Anders Huseth, Ph.D., assistant professor and extension specialist in entomology at North Carolina State University, uses the maps to help farmers understand how to prevent insecticide resistance and to communicate to IPM students how pesticide use varies across the U.S. landscape.

In recent years, the data available in the USGS Pesticide National Synthesis Project has been reduced, as these examples illustrate. Top row: The insecticide clothianidin is primarily used as a seed treatment. At left is the map showing the estimated use pattern in 2014, while at right is what the map looked like after seed treatments were no longer included in the dataset in 2015. Bottom row: The common insecticide bifenthrin is used in corn, soybeans, cotton, wheat, and fruits and vegetables, among other crops. The map at left shows its use pattern in 2018; as illustrated at right, this information was entirely absent after bifenthrin was dropped from the dataset in 2019. (Images downloaded from the USGS Pesticide National Synthesis Project by Maggie Douglas, Ph.D.)

Cutbacks Leave a Huge Gap

Unfortunately, the scaling back of the USGS program has radically reduced its value to the scientific community, educators, diverse organizations, and the public—and further cuts are in progress.

In 2015, the dataset stopped including seed-applied pesticides, one of the most widespread methods of application, and one that is not reported anywhere else. In 2019, the scope narrowed further to track only 72 pesticides, reducing the number of tracked chemicals by roughly 80 percent and the amount applied by 40 percent. Recently, the agency announced that, after 2024, the data will only be updated every five years, a significant lag given how quickly the pest management landscape changes.

The reasons for the cutbacks are still not entirely clear. Funding constraints are an obvious hypothesis but do not seem to be the full explanation. The data at the heart of the program come from farmer surveys administered by a private research firm, which are then purchased and processed by USGS into the dataset it provides. Public records show that the raw data cost USGS no more than $150,000 per year at its height, a tiny fraction of the agency’s current $1.7 billion annual budget and a modest price tag for this invaluable information.

Whatever the underlying reasons, these losses of pesticide usage data leave scientists and the public in the dark.

What You Can Do

No matter your perspective or role, you can speak your mind about the value of Pesticide National Synthesis Project:

1. Contact your Congressional representatives. Encourage them to write a letter to USGS requesting an explanation for the cutbacks and expressing support for restoring the program. (For guidance, see this shared document with talking points and Congressional contact info.)
2. If you use the Pesticide National Synthesis Project maps, graphs, or data in your work, please fill out this brief survey by July 3. Responses will aid in demonstrating the value of the program and what stands to be lost if it is not reinstated.
3. Spread the word. Contact the organizations you belong to and encourage them to engage in support of the Pesticide National Synthesis Project. Many organizations have policy arms that may be in a good position to advocate for the program.

Thank you for speaking out to restore this essential pesticide database!

Maggie Douglas, Ph.D., is an assistant professor of environmental science at Dickinson College in Carlisle, Pennsylvania. Email: douglasm@dickinson.edu.

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Source: Xinhua| 2023-06-16 00:26:30|Editor: huaxia

NAIVASHA, Kenya, June 15 (Xinhua) — The Food and Agriculture Organization (FAO) of the United Nations on Thursday launched a project in Kenya’s lakeside town of Naivasha to protect staple food crops from devastating losses caused by the African armyworm, a pest which can destroy up to 100 percent of staple foods if left uncontrolled.

The project, Emergency Support to Manage Outbreaks and Infestation by African Armyworm in Eastern Africa, aims to harness national capacities in eastern Africa against the incursion of the pest.

Xia Jingyuan, director of the Plant Production and Protection Division at the FAO, said the pest poses a serious threat to food insecurity in the subregion, necessitating the urgent intervention of the FAO and its partners to prevent major loss of crops, which are already under pressure of prolonged drought.

Xia said the pest is reproducing itself for up to 13 generations in a single year, with a huge potential for major outbreaks. “In 2022, the outbreaks were reported in many East African nations. Recognizing this challenge, FAO is employing its expertise to protect the livelihoods of smallholders through robust monitoring and management of the pest,” he said in a statement.

The FAO said the project aims to harness national capacities in eastern Africa against the incursion of African armyworms. It extends support to six countries in the region — Eritrea, Ethiopia, Kenya, Somalia, South Sudan, and Uganda.

“By establishing 2,400 monitoring sites, with 400 sites in each country, the project provides training to over 1,350 people in monitoring, early warning, and effective management techniques for African armyworm,” the FAO said.

Kello Harsama, principal secretary of the State Department for Crop Development at the Ministry of Agriculture and Livestock Development of Kenya, noted the fact that Kenya had just come out from the worst desert locust invasion that threatened farmers’ lives and livelihoods in more than 28 counties and was again facing the dangers of the African armyworm.

Harsama said Kenya has carried out surveillance on over 1.12 million hectares, of which about 296,000 hectares were found to be affected by African armyworms. “So far, over 173,000 hectares of land were protected through ground spraying. However, effective and lasting protection can be achieved through regional collaborative efforts,” Harsama said.

The project focuses on engaging experts from National Plant Protection Units within the Ministries of Agriculture as the primary beneficiaries, while also providing in-country knowledge transfer training to national experts and community focal persons in villages. The project emphasizes the use of a Community-Based Armyworm Monitoring and Forecasting system, which was started in Tanzania in 2000, with subsequent rollouts in Ethiopia and Kenya.

The system has demonstrated promising results and was scaled up in high-risk villages in Ethiopia, Kenya, and Tanzania from 2012 to 2015.

Carla Mucavi, the FAO representative in Kenya, said the African armyworm is a transboundary pest that threatens food security and nutrition in the whole of the East Africa subregion.

Muvaci said the pest can cause serious damage to staple foods unless it is monitored and managed.

“No single country can manage this pest alone. We need to join hands to defeat this pest, so as to prevent major crop losses that endanger the livelihoods of the smallholder farmers. Thus, I call upon governments and partners to put on more resources to catalyze and enhance the fight against this worrisome pest,” Mucavi said. ■

Mealybugs are a common insect pest in greenhouses, causing damage to plants and reducing yields. Mealybugs extract plant fluids through their piercing-sucking mouthparts, leading to stunted growth, yellowing leaves, wilting, and the production of sticky honeydew. Mealybugs can be introduced into greenhouses through tropical foliage and succulent plant material shipments, making effective control strategies important. A combination of cultural, insecticidal, and biological management strategies need to be implemented to manage mealybug populations.

Figure 1. Adults, nymphs, and egg masses of citrus mealybugs. Photo by the United States National Collection of Scale Insects Photographs, USDA Agricultural Research Service, Bugwood.org.

Identifying mealybugs is relatively easy due to their elliptical shape and distinctive white, waxy filaments protruding from their body. While they retain their legs in all instar stages, mealybugs seldom move except for the first nymphal instar stage or crawler, which actively searches for a place to feed. Some species leave behind white, cottony egg masses (Figure 1) and excrete honeydew, which can lead to the growth of black sooty mold. Their ability to hide in plant crevasses makes them particularly difficult to manage. Since only adult male mealybugs fly, yellow sticky cards are not effective for scouting. Therefore, using a hand lens or magnifying glass to confirm the identity of mealybugs is recommended. Keeping records of mealybug infestations and locations will help in making effective management decisions.

Disposal and quarantining
One of the most effective ways to stop the spread of mealybugs in the greenhouse is to dispose of heavily infested plant material (Figure 2). Setting up pest thresholds in your operation is important to determine when to cut your losses and throw away plant material. A pest threshold is a level at which a pest population in a crop reaches the point where it begins to cause economic losses. In other words, it is the point at which the cost of controlling the pest exceeds the cost of the damage it causes to the crop. Determining a pest threshold requires a comprehensive assessment of the crop, pest, economic factors, and the availability and effectiveness of management options. Plant material susceptible to mealybugs should be quarantined before introducing into the greenhouse. For high-value crops where disposal is not ideal, quarantining infested plants helps ensure mealybugs do not spread to unaffected plants. Quarantine protocols will be different depending on the size of the operation and the crop type, but the basic steps include the following:

1. Isolation: Place new plants in a separate area, away from the main greenhouse, to prevent the spread of mealybugs to other plants. This could be an area as large as a greenhouse or as small as a grow tent.
2. Inspection: Before bringing new plants into the greenhouse, inspect them thoroughly for mealybugs, focusing on growing tips and areas where the leaf attaches to the stem (Figure 3).
3. Prevention: Rejecting the shipment and contacting the supplier may be necessary.
4. Treatment: If mealybugs are found on new plants, treat plants with an insecticide before introducing them into the greenhouse. Thorough coverage of all plant parts is important and multiple applications will be required.
5. Monitoring: Regularly inspect quarantined plants for mealybugs and treat them with an insecticide as needed.
6. Record keeping: Record when and where mealybugs are found, the severity of the infestation, and any insecticides applied. Record-keeping will help determine the effectiveness of the quarantine measures.

Figure 2. Marigold plant heavily infested with citrus mealybugs that should be disposed of. Photo by Chazz Hesselein, Alabama Cooperative Extension System, Bugwood.org. 

Figure 3. Citrus mealybugs on stem of plant. Photo by Charles Olsen, Charles Olsen Insect Collection, USDA APHIS PPQ, Bugwood.org. 

Sanitation
Proper greenhouse sanitation is crucial to mitigate the spread of mealybugs. It is important to keep greenhouses clean. Doing so will help to minimize mealybug problems before the spring growing season begins.

The first step in greenhouse sanitation is to remove all plant debris. Weeds, plant debris, and unsalable plants can serve as hosts for insects, mites, diseases, and plant viruses. Reading the Michigan State University Extension Greenhouse Weed Management Strategy is recommended for managing weeds. Remove all weeds and plant debris and place them into a tightly sealed, covered garbage container to prevent pests and pathogens from migrating out and back onto the main crop. Remember to remove organic material and debris (media, spent plants, other organic material) daily to increase the effectiveness of disinfectants.

Mealybugs are easily spread in a greenhouse. Therefore, educating employees/workers on the importance of sanitation practices is important. Workers should be trained to identify signs of mealybug infestations on plants and the areas in the greenhouse where mealybugs are commonly located to prevent infestations from spreading. It is also important to remind workers to wash their hands frequently and disinfect not only tools and equipment but also any containers, trays, or other items used to transport plants. By taking these measures, workers can help reduce the risk of spreading mealybugs in a greenhouse.

Pesticide control
Due to their protective waxy covering, mealybug populations can be challenging to manage with insecticides. The covering is water-resistant and reduces their exposure to insecticide residues. Most insecticides have limited activity on mealybug eggs. The nymphal stages are the most susceptible to insecticides because they have not formed the waxy covering. Insecticides need to be applied frequently, at least once per week, due to the presence of multiple generations.

When using insecticides to manage mealybug populations, be sure to rotate insecticides with different modes of action. This will reduce the likelihood of mealybugs developing resistance. Refer to the Insecticide Resistance Action Committee (IRAC) website for information pertaining to insecticide modes of action.

For a complete list of recommended insecticides for managing mealybugs, check out the MSU Extension Greenhouse Pest Management Guide.

Biological control
Biological control agents, such as mealybug destroyers (Cryptolaemus montrouzieri) (Figure 4) and lacewing larvae (Chrysoperla spp.), can be purchased and released to manage mealybug populations.

Figure 4. Cryptolaemus montrouzieri adult feeding on citrus mealybug. Photo courtesy of Sonya Broughton, Department of Agriculture & Food Western Australia, Bugwood.org.

Source: canr.msu.edu

Publication date: Wed 24 May 2023

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une 15, 2023

Laura Hollis

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Use the Crop Sprayer app to improve your Integrated Pest Management strategy

The Crop Sprayer mobile app is the latest tool in the PlantwisePlus Toolkit. The free app helps users apply just the right amount of pesticide to treat and protect crops from pests.

Growth in pesticide use

Farmers lose up to 40% of their crops to pests and diseases. The increase in devastating species, such as the fall armyworm, papaya mealybug and tomato pinworm, has led to a growth in pesticide use among smallholder farmers. However, the misuse and overuse of chemicals can harm human health and the environment.

One solution for reducing pesticide risks is to follow an Integrated Pest Management (IPM) strategy. IPM is a holistic and sustainable approach to pest control. It combines physical, cultural and chemical practices to economically control crop pests whilst minimising hazards. As such, IPM strategies aim to reduce the use of pesticides.

Careful use of pesticides

IPM includes the use of pesticides, but only after monitoring indicates action thresholds have been exceeded. Applying the correct pesticide at the recommended dose is very important to minimise risks to human health, beneficial and nontarget organisms, and the environment.

This is when the Crop Sprayer app can be of benefit. Through the app, users can quickly work out simple calculations, including how much pesticide to put in their sprayer, how much pesticide they need in total, and how many tanks they require for an area.

When is it appropriate to incorporate pesticides into an IPM strategy, and how can the Crop Sprayer app help?

Identification and monitoring of pests

The first step in IPM is to identify and monitor the pest. Understanding the pest species, its behaviour, and its life cycle can help determine whether non-chemical methods alone are sufficient or if pesticide intervention is required.

View the PestSmart Diagnostic Field Guide

Threshold levels of pests

Threshold levels are predetermined pest population levels at which a farmer should take action to prevent economic or environmental damage. Utilising thresholds helps prevent unnecessary pesticide applications and ensures that treatments are targeted and effective.

Selective pesticides

When pesticides are deemed necessary, farmers should choose products that target the specific pest. Selective pesticides, also known as soft pesticides, reduce the risk of disrupting natural predator-prey relationships.

Pesticide resistance management

Pesticide resistance is a significant concern in pest management. Overreliance on a single pesticide can lead, over time, to resistance in pest populations, rendering the pesticide ineffective.

Using pesticides strategically and sparingly can help slow down pesticide resistance. Farmers can do this by rotating between chemical modes of action and employing other non-chemical control methods, such as biocontrols.

Cost-Benefit Analysis of pest problem

Assessing the potential economic losses from the pest problem compared to the costs associated with pesticide application allows farmers to understand if the economic benefits of pesticides outweigh the costs. Cost considerations include the product, application equipment and labour.

Using the Crop Sprayer app

If a farmer decides it is appropriate to use pesticides as part of their IPM strategy, then the Crop Sprayer app can help with the often tricky calculations. The app supports farmers and agricultural advisors, ensuring they can calibrate the output of their sprayers and purchase and use the right amount of pesticide. Not only does this help tackle issues around misuse and overuse, but it also means farmers do not have unused pesticides left over. Leftover chemicals cost the farmer money unnecessarily, as well as pose challenges with pesticide disposal.

About the Crop Sprayer app

The Crop Sprayer App is free for everyone to download and use and is available in English, French, Spanish, Swahili and Bengali.

Users require an Android smartphone or tablet with enough storage space for the app and access to the internet to download the app from the Google Play Store.

Once downloaded, the app works offline. However, a stable internet connection and sufficient storage space on your device are needed for any updates released by CABI.

data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw== The new Crop Sprayer mobile app

CABI Bioprotection Portal

The CABI BioProtection Portal can be used alongside the Crop Sprayer App as it provides up-to-date information to identify, source and apply registered microbial biopesticide products in a given country, thereby supporting the rational application of nature-based pest management solutions.

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Entomology Today 8 hours ago Leave a Comment

During the Biocontrol Field Tour hosted by the ESA Plant-Insect Ecosystems Section in the Wenatchee, Washington, area in May 2022, tour participants meet at a Zirkle Fruit orchard for the second day of the tour. (Photo by Suzanne Wainwright)

By Rebecca Schmidt-Jeffris, Ph.D., Dalton Ludwick, Ph.D., Alix Whitener, Ph.D., and Teah Smith

In May 2022, the ESA Plant-Insect Ecosystems (P-IE) Section hosted a Biocontrol Field Tour in the Wenatchee, Washington, area. The tour was part of a series of tours held by the P-IE Section and the first tour to be held since the COVID-19 pandemic started. Past tours focused on pollinators (Mississippi Delta in 2017, North Dakota in 2018), invasive species (southeastern Pennsylvania in 2018), and pesticide resistance management (Nebraska and Iowa in 2019). P-IE has historically partnered with other ESA sections and other societies (e.g., Weed Science Society of America) as appropriate for these tours.

The biocontrol tour was held against the backdrop of the Washington state tree fruit industry, which has a long history of successful implementation of classical, augmentative, and conservation biological control. Fifty-two participants met the first evening at Pybus Public Market for dinner and discussions to set the stage for the tour. Initial discussion groups mixed tour participants to ensure that each table encompassed a variety of viewpoints, including university researchers, U.S. Department of Agriculture (USDA) researchers, growers, crop consultants, and biocontrol and agrochemical industry professionals.

Participants were asked to describe the biggest challenges for biocontrol implementation from the perspective of their current position or crop system and to brainstorm potential solutions to these challenges as a group. While the details of the challenges varied, in general, groups agreed that education—through additional research and extension activities—and improved communication between groups were key to addressing the challenges. This networking activity was one of the most enjoyed parts of the tour, and one participant noted that, “Having a small group of the right people in the room is the way to share information and get problems solved.”

Zirkle Fruit Company hosted the field components of the tour at its Othello Ranch location. We started the day with demonstrations of deploying natural enemies for augmentation via drone (by G.S. Long Company and Parabug) and via a vehicle-mounted blower (by Koppert). Other insectary companies provided updates about available natural enemies and other products, and the team from Washington summarized ongoing research on release best practices. Sunview Vineyards (California) described the operation for rearing its own predatory mites for release to control spider mites. Participants walked through an on-farm native floral planting to scout for beneficial insects and were given an overview of the environmental and economic benefits of the planting by Zirkle’s Teah Smith and Corin Pease of the Xerces Society.

Next, a set of classroom talks covered a variety of topics on conservation biological control, including pesticide compatibility and a summary of the history of conservation biological control in Washington tree fruit, courtesy of Betsy Beers, Ph.D., of Washington State University. The day ended with a talk by Judith Stahl, Ph.D., of the University of California, Berkeley, on the classical biological control quarantine and approval process and a ceremonial “releasing of the wasps” by Jana Lee, Ph.D., project lead for the spotted wing drosophila areawide management project at the USDA Agricultural Research Service (ARS), including releases of Ganaspis brasiliensis.

The next morning, the group met at Walla Walla Point Park for donuts and coffee and to discuss what they had learned from the tour. Nearly all participants agreed that they gained useful information during the tour and would apply something that they had learned. The most popular “take home” ideas were beneficial plantings and releasing biocontrol agents (either from a practitioner or researcher perspective). Networking opportunities were by far the most popular part of the tour. Industry professionals hoped that the tour showed students that biological control was a viable career, emphasizing that all aspects of the industry need trained, motivated practitioners with a well-rounded agronomic background to be successful.

During the Biocontrol Field Tour hosted by the ESA Plant-Insect Ecosystems Section in the Wenatchee, Washington, area in May 2022, participants viewed a demonstration of releasing lacewings into an orchard using a drone. (Video by Aaron DeHerrera)

Participants came away with an increased understanding of the importance of demonstrations to show the viability of particular management tools. Growers emphasized that it is important to set realistic expectations, because biocontrol often requires a longer timeline to demonstrate its success than pesticides. Areas where more research is most needed were underscored: quantifying biocontrol effects and economic analysis in a variety of crops, making tailored best-practice recommendations, and developing management thresholds that include natural enemies (i.e., “farmer-izing” biocontrol) in the equation.

The tour provided networking opportunities for entomology graduate students and early career professionals. Thanks to more than $5,000 in sponsorships, we were able to provide travel support to two students and two ECP members, who received funding through a competitive application process. Congratulations once again to Monica Farfan, Ph.D., executive director of the Global Soil Biodiversity Initiative at  Colorado State University; Ashley Leach, Ph.D., assistant professor at Ohio State University; Julian Cosner, doctoral student at the University of Tennessee; and Charlotte Schuttler, master’s student at Michigan State University. Sponsors included Certis Biologicals, Corteva Agriscience, FMC Corporation, Marrone Bio Innovations, and Trécé, Inc.

On the third and final morning of the Biocontrol Field Tour hosted by the ESA Plant-Insect Ecosystems Section in the Wenatchee, Washington, area in May 2022, participants gathered for a group photo after breakout discussions. (Photo by Dalton Ludwick, Ph.D.)

Did you miss out on the 2022 field tour? More P-IE Section field tours are still to come! This year, an Invasive Species Field Tour will be held in Orlando, Florida, September 12-14, 2023. The tour will focus on various invasive pests affecting natural and managed landscapes in the southern U.S., including forest pests, agricultural pests, and pests in urban and suburban areas. Experts in entomology and pathology who are focused on both research and management will discuss how these pests arrived, what we are trying to do about them, and what the future holds for invasive pest detection and management. Learn more and register by July 31 for a discounted rate.

Do you have an idea for a future field tour? The P-IE Section is seeking new tour ideas and organizers for 2024 and beyond. Contact P-IE Section leadership if you have an idea or for more information on how to plan a successful tour.

Rebecca Schmidt-Jeffris, Ph.D., is a research entomologist at the USDA-ARS  Temperate Tree Fruit & Vegetable Research Unit in Wapato, Washington. Email:  rebecca.schmidt@usda.gov. Dalton Ludwick, Ph.D., is an assistant professor and extension entomologist at the Texas A&M AgriLife Extension Service in Corpus Christi, Texas. Alix Whitener, Ph.D., is the U.S. field development manager at FMC Corporation in Malaga, Washington. Teah Smith is an entomologist and agriculture consultant at Zirkle Fruit Company in Wenatchee, Washington.

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Nematode infestations are not as obvious as armyworms, thrips, or fleahoppers, but the damage they cause to numerous crops can be devastating. Farm Press called on Extension and Research pathologists From Texas to Georgia to ascertain the damage nematodes can cause, the symptoms to look for in-season, sampling recommendations, and management options. Also, new research seeks to find more varieties resistant to nematode damage.The first and most crucial part of managing nematode infection is identifying the problem, including determining level of pressure and specific species present.Timing and collection of representative samples are critical to identifying infection levels and creating a viable management plan.“Sampling should wait until at least 60 days after planting,” Terry Wheeler, Texas A&M AgriLife Research Pathologist, Lubbock, said. “Soil sampling for a nematode analysis is fine from 60 days to the end of the season, as long as there is good soil moisture.”She said soil tends to dry out in the fall, so sampling during the growing season “is usually better.”“Taking soil samples is the only way to determine the population density of root-knot or reniform nematode,” said Travis Faske, University of Arkansas Division of Agriculture, Lonoke.Related:Unmanaged nematode damage can exceed 50%He added that other nematodes, including lesion nematode or lance nematode, could be a problem in some states. “Lance is generally not a problem here.”He said the best time to sample in his area is just after harvest.

Sampling is crucial

“Sampling is the only way to detect problems of nematodes other than root-knot nematodes, the only one if you were scouting you could see stunted plants showing nutrition deficiencies in mid-season and could dig up and see galling.“That’s where I come in, sampling and getting farmers to sample. I’ve talked with some who say they have sampled. I ask, how long ago? ‘Well, about 15, 20 years ago’ they say. A lot of things change within their production system in that time.”“Fall is the best time,” said University of Georgia Extension Plant Pathologist Bob Kemerait, Tifton.But Kemerait said some Georgia farmers were sampling this winter. “We were seeing a number of samples come back positive for high levels of nematodes, which is unusual for samples collected during cooler winter months,” he said.He attributes those high populations to several La Niña winters, winters that are warmer than average and that allow nematodes to continue to feed.And during the winter of 2022-2023 they had a buffet. “In warmer winters, some cover crops or winter wheat could be a host,” he said. “Some common winter weeds like henbit and chickweed also might be a host in a warm winter. In a winter like we’ve had this year, nematodes never really went to bed and may want to go out and get themselves a snack.”Related:Resistant varieties, rotation suppress reniform nematodesHe said plants typically not a good host in colder winters could become fair hosts in warmer winters.Does it make sense to sample in the winter?“That’s a great question,” Kemerait said. “I would say under most circumstances no. It’s too late. But we’ve had growers across Georgia who, against my better judgment initially, took samples. They wanted to know what was in their fields. Surprisingly, we’ve found some very high levels of nematodes.”He cited two reasons to avoid taking samples during winter months. “The first is if you come back with nothing in the sample, you don’t know if that’s because there’s nothing there or because you sampled in the winter when nematode populations are suppressed. Also, our threshold levels are based upon fall counts, not spring. That makes interpretation of winter numbers a bit difficult.“On the other hand, because it’s been so warm this winter, we find successful growers who have nematode pressures at elevated levels, which we normally wouldn’t see this time of year.”Kemerait said some growers are making good decisions based on what they find in late nematode samples.“Still, I wish they had sampled in the fall.”Related:Nematode symptoms may resemble nutrient deficiencyHe added that if growers get samples with high numbers, they can make management decisions. “But if they don’t get low numbers back, they can’t know for sure if they have nothing or the timing is off. I prefer that growers sample in the fall, just after harvest, before soils get cold.”

Population changes

Faske said producers should consider that nematode population density could change over time and sometimes in spite of resistant varieties.He said producers may say, “’I don’t have a nematode problem,’ referring to root-knot but don’t think about reniform. Without a soil sample they don’t know.”Faske explained that nematode samples can be predictive or diagnostic.“If growers see a problem, stunted plants, for instance, they take a diagnostic sample to determine why those plants are stunted. They would take a sample in sick-looking plants, not the dead plants. Nematode populations will be low in dead plants.”He recommended comparing the sample area to a lush and green area in cotton, soybeans, or peanuts. “Send those two samples off and compare nematode numbers to determine if the symptom you’re seeing is related to nematode density.”He said producers take predictive samples in the fall.“Then they should ask if they can predict damage based on nematode density or are they at a level that would cause damage for a subsequent crop, cotton, soybeans or peanuts.”

Representative sample

He said samples should represent the field as accurately as possible.Samples do not have to be large, Faske said. “We don’t need a gallon of soil.”Wheeler recommends taking a composite soil sample (10 to 20 spots per sample) to a depth of 8 to 12 inches.  “You can be close to the surface, 6 to 8 inches, nearer to midseason, deeper as you get close to harvest. “Take the sample near the taproot. Mix the soil well in a bucket and put it in a plastic bag,” she said.  “Keep the sample from getting hot, or from freezing.  Nematodes are very sensitive to extreme temperatures.”Faske recommends producers stay with the same laboratory from year to year.“Although the process is generally the same, sometimes the way labs report findings are a little different.” He said Arkansas reports as per 100 cubic centimeters of soil; Mississippi reports as 500 cubic centimeters of soil; Missouri reports as 250 cubic centimeters of soil.

Thresholds

He said thresholds for nematode populations, unlike for insect pests, are difficult to establish.“If samples show more than 100 per 100 cubic centimeters of soil per root, that’s a serious problem going into soybeans or cotton and growers should think about a management tactic.”Faske said Arkansas commodity boards see nematode sampling as a critical tool in crop management and have “put their money where their mouth is, providing free assays to farmers. For the past few years, commodity boards have been paying for nematode assays.”All three agree, growers have to know what’s there before they can develop a management plan.

8 key tips for nematode sampling

Timing and technique are critical aspects of pulling, protecting, and transporting nematode samples.Morgan McCulloch, Texas A&M AgriLife, San Angelo, and Travis Faske, University of Arkansas, Division of Agriculture, Lonoke, offer tips to collect nematode samples.

Thursday, 20 April 2023 09:17:00

PestNet

Grahame Jackson posted a new submission ‘BUD ROT, OIL PALM – COLOMBIA: (CESAR)’

Submission

BUD ROT, OIL PALM – COLOMBIA: (CESAR)

ProMED

Source: Breaking Latest News [summ. Mod.DHA, edited]
https://www.breakinglatest.news/news/about-78-thousand-hectares-of-oil-palm-in-cesar-have-a-phytosanitary-threat/

Nearly 78 000 hectares [about 192 740 acres] of oil palm in the department of Cesar are threatened by the growing number of outbreaks of bud rot which could severely affect the plantations. Cenipalma (Oil Palm Research Center Corporation) calculations indicate that, if a regional contingency plan is not implemented to control and overcome the disease, by January 2026 98.8% of oil palms in the department could be affected. Similar situations have already occurred in the department of Magdalena, forcing the elimination of hundreds of hectares of oil palm plantings and replanting with more resistant cultivars.

A forum of stakeholders is being held to discuss phytosanitary issues, projections, and regional strategies for the management of bud rot. For now, there is talk of “isolated foci” in Cesar, but tasks such as proper drainage, avoiding flooding, phytosanitary monitoring, and nutritional management cannot be postponed.
—
Communicated by:
ProMED

[While a number of fungi can cause bud rots in palms, the disease caused by the oomycete _Phytophthora palmivora_ has emerged as the main threat to Latin American commercial oil palm (_Elaeis guineensis_) monoculture since the early 2000s. Tens of thousands of hectares of palms are affected with entire estates destroyed in Panama, Colombia, Suriname, Brazil, and Ecuador; the disease is the limiting factor for oil palm cultivation in the region.

Trees of all ages can be affected; they also become more susceptible to secondary insect or pathogen infestations or adverse environmental factors. In palms, symptoms start with discolouration of the spear leaf followed by extensive frond rots as the infected leaf unfolds. The rot progresses into the leaf base killing the single growing bud and thus eventually the tree. Disease incidence is usually more severe in high humidity.

The pathogen enters the host via the crown. It is spread by wind splashed rain, mechanical means (including insect activities, cutting knives), and with infected plant or other material; it can remain dormant in the leaf base during dry conditions. Disease management may include cultural practices (phytosanitary measures, nutritional improvements), removal and burning of severely affected palms, as well as treatments with appropriate agrochemicals (for example copper compounds) at or before onset of symptoms. Different palm varieties or hybrids may show different levels of susceptibility to bud rot. For oil palm, breeding programmes using possible bud rot resistance genes from _E. oleifera_ (indigenous to the Americas) are in progress.

_P. palmivora_ is known to affect more than 150 tropical hosts, including black pod of cocoa (e.g. ProMED post 20220913.8705557). New strains that spread faster and are more difficult to control are emerging.

Maps
Colombia:
https://promedmail.org/promed-post?place=8709576,37967 and
https://www.nationsonline.org/maps/colombia_pol_map.jpg (with departments)
South America, overview:
http://ontheworldmap.com/south-america/political-map-of-south-america.jpg

Pictures
Bud rot symptoms on oil palm:
http://www.scielo.org.co/img/revistas/agc/v32n3/v32n3a11f1.jpg and
https://apsjournals.apsnet.org/cms/10.1094/PHYTO-09-15-0243-RVW/asset/images/large/phyto-09-15-0243-rvw_f2.jpeg
Bud rot symptoms on coconut and other palms:
http://www.ctahr.hawaii.edu/nelsons/palms/coconut_heart_rot_1.JPG,
http://www.ctahr.hawaii.edu/nelsons/palms/cocorot-crown.jpg,
http://www.extento.hawaii.edu/kbase/view/files/pictures/Img0013.jpg, and
https://edis.ifas.ufl.edu/image/9028744/screen

Links
Bud rot of palms:
https://edis.ifas.ufl.edu/publication/PP144,
https://apps.lucidcentral.org/ppp_v9/text/web_full/entities/coconut_bud_rot_140.htm,
https://agenciadenoticias.unal.edu.co/detalle/more-aggressive-isolates-of-oil-palm-bud-rot-identified,
https://apsjournals.apsnet.org/doi/10.1094/PHYTO-09-15-0243-RVW, and
https://doi.org/10.1017/S0014479703001315 (review)
Information on other _P. palmivora_ diseases and hosts:
http://www2.ctahr.hawaii.edu/adap2/ascc_landgrant/Dr_Brooks/BrochureNo12.pdf
_P. palmivora_ taxonomy and synonyms:
http://www.indexfungorum.org/Names/NamesRecord.asp?RecordID=194605 and
https://www.speciesfungorum.org/GSD/GSDspecies.asp?RecordID=194605
_Phytophthora_ diseases, impact, and management:
http://www.baumkrankheiten.com/downloads/phytophthora-importance.pdf and via
http://edis.ifas.ufl.edu/hs254
Cenipalma:
https://www.cenipalma.org/
– Mod.DHA]

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Entomology Today 2 weeks ago 1 Comment

Cultivation of transgenic crops engineered to produce insecticidal proteins from Bacillus thuringiensis (Bt) has grown rapidly in the past 25 years. Bt crops have had noteworthy successes, but resistance to Bt crops has evolved in numerous instances. Five cases of practical resistance to Bt proteins that are produced by transgenic crops are documented for corn earworm (Helicoverpa zea), which is the most for any pest. (Photo by John C. French Sr., Retired, Universities:Auburn, GA, Clemson and U of MO, Bugwood.org)

By John P. Roche, Ph.D.

Insect pests damaging crops is a huge problem worldwide, threatening food security and causing significant economic loss. One avenue to address this is to genetically engineer crops to produce proteins from the bacterium Bacillus thuringiensis (Bt) that kill pests but are safe for most nontarget organisms. Although Bt-modified crops have been useful for controlling pests in numerous instances, some pests evolve resistance to Bt insecticide proteins. Therefore, scientists must evaluate the efficacy of Bt modified crops and find ways to delay evolution of insecticide resistance.

Sustained susceptibility to Bt cotton was essential for eradicating the pink bollworm (Pectinophora gossypiella) from the United States and Mexico, which it had invaded more than a century ago.As part of a multi-tactic program, pink bollworm caterpillars were mass reared (as shown here) and 11 billion sterile moths were released by airplanes to overwhelm its populations in the field. By contrast, this pest evolved resistance to dual-toxin Bt cotton in India, where it was used extensively with scarce non-Bt host plant refuges and limited integration of other tactics. (Photo by Alexander Yelich, University of Arizona)

In a review published in January in the Journal of Economic Entomology, Bruce Tabashnik, Ph.D., and Yves Carrière, Ph.D., of the University of Arizona and Jeffrey Fabrick, Ph.D., of the USDA Agricultural Research Service analyze both of these needs by examining patterns of Bt resistance in agricultural pests around the globe. The review is part of a special collection on field-evolved resistance to Bt crops.

The acreage of Bt-modified crops has grown rapidly in the past 20 years, with over a 100-fold increase between 1996 and 2019. The USDA estimates that, in the U.S. from 2009 to 2020, Bt crops accounted for more than 75 percent of the area planted with corn and cotton and that, from 2016 to 2020, 81 percent of corn and 87 percent of cotton planted in the U.S. was engineered to produce Bt proteins.

Bt crops have helped to suppress pests while also decreasing the need for conventional insecticides and augmenting the effectiveness of biological control species. “Two stunning successes of Bt crops against invasive pests in the United States,” Tabashnik says, “are suppression of the European corn borer (Ostrinia nubilalis) to its lowest levels in more than 75 years by Bt corn and eradication of the pink bollworm (Pectinophora gossypiella) using Bt cotton together with sterile moth releases and other tactics.” An example of a success against a native pest is the control of the tobacco budworm moth Chloridea virescens using Bt cotton in the U.S. and Mexico.

In their review, Tabashnik, Carrière, and Fabrick examined 73 sets of data on monitoring resistance to Bt crops, including information about responses to 10 Bt toxins in 22 species of moth and two species of beetle. They differentiated resistance found in these studies into the following three categories:

1. practical resistance, in which more than half of the individuals in a population are resistant and the field efficacy of the Bt crop has decreased;
2. early warning of resistance, in which resistance has evolved but fewer than half of individuals are resistant and efficacy of the Bt crop has not decreased;
3. no decrease in susceptibility, in which there is no statistically significant decrease observed in susceptibility.

In the 73 data sets examined, they found 26 cases of practical resistance. The average time from first planting of a particular Bt crop to the appearance of practical resistance was 6.6 years. Over half of the cases of practical resistance were in three species—the moths Helicoverpa zea and Spodoptera frugiperda and the beetle Diabrotica virgifera virgifera. Geographically, half of the instances of practical resistance were in the U.S. This makes sense, as the U.S. has planted Bt crops widely and extensively monitored resistance.

Tabashnik and colleagues found 17 instances of early warning of resistance. The mean time of detection of early warning of resistance was 8.6 years after exposure to Bt crops.

Thirty instances of no significant resistance were found after two to 24 years of exposure, with an average duration since exposure to Bt crops of 12.2 years.

The many instances of practical resistance lead to the question of how resistance can be delayed or prevented. One important way to reduce resistance is by creating refuges consisting of non-Bt-modified plants that serve as hosts for pest insects that are not resistant. Refuges were first envisioned to reduce evolution of resistance to insecticide sprays, but they have been crucial for slowing evolution of resistance to Bt insecticides. Because the refuge plants don’t produce Bt proteins, they allow survival of susceptible insects that can mate with any resistant insects that emerge from Bt crops.

Another factor that can hinder the evolution of resistance is increasing the concentration of Bt proteins enough to kill insects that are heterozygous for resistance, i.e., they carry only one allele that confers resistance. This “high-dose” strategy makes the resistance functionally recessive and less likely to spread quickly.

Tabashnik says, “Theory and empirical evidence indicate that recessive inheritance of pest resistance to Bt crops and abundant refuges of non-Bt host plants can help to sustain the efficacy of Bt crops. When inheritance of resistance is not recessive, the abundance of refuges relative to Bt crops can be increased to effectively delay evolution of resistance.”

Strategies being explored to heighten the efficacy of Bt crops include targeting each pest with two or more Bt proteins and using Bt proteins together with RNA interference (RNAi) insecticides. In the close of their review, Tabashnik and colleagues emphasize that rather than relying on any one control tactic—such as transgenic crops—sustainable pest suppression combines diverse integrated pest management tools.

Read More

“Global Patterns of Insect Resistance to Transgenic Bt Crops: The First 25 Years”

Special Collection: Global Perspectives on Field-Evolved Resistance to Transgenic Bt Crops

Journal of Economic Entomology

John P. Roche, Ph.D., is an author, biologist, and science writer with a Ph.D. in the biological sciences and a dedication to making rigorous science clear and accessible. He writes books and articles, and provides writing for universities, scientific societies, and publishers. Professional experience includes serving as a scientist and scientific writer at Indiana University, Boston College, and the University of Massachusetts Medical School, and as editor-in-chief of science periodicals at Indiana University and Boston College.

In the Philippines, GMO crops are regulated by several government agencies, and Bt eggplant, Bt corn, and Golden Rice are some of the approved GMO crops considered safe for human consumption and the environment, which passed a rigorous scientific assessment.

BY James Tababa

May 3, 2023 00:06 AM

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• In the Philippines, GMO crops are regulated by several government agencies, and Bt eggplant, Bt corn, and Golden Rice are some of the approved GMO crops considered safe for human consumption and the environment, which passed a rigorous scientific assessment.

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(icono/Pexels)

By JAMES TABABA

Genetically modified (GM) crops or genetically modified organisms (GMO) have been developed and grown since the 1990s. They are created through the process of genetic engineering, where the DNA of an organism is modified to produce desirable traits. GM crops are created to increase yield to increase food production, reduce the need to use pesticides and other harmful chemicals by creating insect pests and disease-resistant crops, and produce a highly nutritional crop to address nutritional deficiencies in certain populations.

The Philippines is one of the countries where genetically modified crops are being grown and used. However, GMO crops in the Philippines are regulated by the Department of Agriculture through the National Committee on Biosafety of the Philippines (NCBP) to ensure safety and prevent negative environmental impact. Evaluation of GMO crops is also supervised by several government agencies before approval for commercial purposes.

Department of Agriculture-Bureau of Plant Industry (DA-BPI) is responsible for the evaluation, regulation, and approval of GMO crops for commercial propagation, release, and field trials. The Department of Environment and Natural Resources-Environmental Management Bureau (DENR-EMB) examines the environmental risk of GMO crops. The Department of Health-Bureau of Food and Drugs (DOH-BFAD) assesses the safety and nutritional value of GMO crops intended for human consumption. Lastly, the Department of Science and Technology-Philippine Council for Agriculture, Aquatic, and Natural Resources Research and Development (DOST-PCAARRD) conducts research and development activities related to GMO crops.

These government agencies collaborate to ensure the safety and potential benefits of GMO crops. They undertake comprehensive evaluations and assessments to ensure that any GMO crops introduced undergo thorough scrutiny regarding their potential impact on the environment, human health, and the agriculture sector.

GMO crops have been a controversial topic in the Philippines. Some groups say that they can help increase food security and boost the country’s agriculture sector, while others expressed concerns over potential environmental and health risks associated with their use. Despite the ongoing debate surrounding GMO crops, the Philippine government has approved some of the GMOs that are considered safe for human consumption and the environment. Here are three of them:

Bt Eggplant

In 2022, The Bureau of Plant Industry of the Department of Agriculture in the Philippines granted a biosafety permit for the commercial cultivation of borer resistant Bt Eggplant to the University of the Philippines Los Baños. Bt eggplant contains a natural protein from the soil bacterium Bacillus thuringiensis, making it resistant to the eggplant fruit and shoot borer. The Philippines becomes the second country, after Bangladesh, to allow the commercial propagation of borer resistant Bt eggplant.

READ: The profitability of planting transgenic eggplants

Bt Corn

Bt corn is a genetically modified variety of corn that has been engineered to be resistant to the Asiatic corn borer (Ostrinia furnacalis). The Asiatic corn borer is a major pest of corn in Asia, and it can cause significant yield losses if left untreated. Bt corn has been genetically engineered to produce a toxin from the soil bacterium Bacillus thuringiensis that is toxic to the pest, thus reducing the need for chemical pesticides.

In the Philippines, Bt corn has been commercially cultivated since 2003, and it is one of the major GM crops grown in the country. Bt corn has several potential benefits for farmers and the environment. By reducing the need for chemical pesticides, Bt corn reduces the environmental impact and health risks associated with pesticide exposure for farmers and consumers. Additionally, Bt corn can lead to higher yields and increased profitability for farmers, which can help to alleviate poverty and food insecurity in rural areas.

READ: Two Cagayano Bt Corn Farmers and Their Advantages

Golden Rice

Golden Rice, now called Malusog Rice, is a genetically modified variety of rice that has been bioengineered to produce beta-carotene, a precursor of vitamin A. It is called “golden” because the rice grains have a golden-yellow color due to the increased presence of beta-carotene, an antioxidant found in fruits and vegetables responsible for the yellow and orange color. The development of Golden Rice was aimed at addressing vitamin A deficiency, which is a serious health problem in many developing countries, including the Philippines.

In the Philippines, the development and testing of Golden Rice have been ongoing since 2004. The project is a collaboration between the Philippine Rice Research Institute (PhilRice), the International Rice Research Institute (IRRI), and other research institutions. In 2022, DA-PhilRice led the pilot deployment of Golden Rice seeds in the Philippines. The rice is registered with the National Seed Industry Council as NSIC 2022 Rc682GR2E or Malusog 1.

READ: Updates on the status of Biotech Corn and Golden Rice in the Philippines

Bt eggplant, Bt corn, and Golden Rice are some of the GMO crops that passed the comprehensive regulatory system for GMO crops that involves several government agencies and a rigorous scientific assessment. This ensures the safety of GMO crops for human health, and the environment.
Read more about farming and gardening at agriculture.com.ph