prostko-spiderwort-2.jpg Dr. Eric Prostko
Benghal dayflower/tropical spiderwort research in Grady County, Ga., peanut field in 2004.

An old weed foe returns — and it’s not pigweed

Benghal dayflower/tropical spiderwort was PUBLIC ENEMY No. 1 prior to the evolution of herbicide-resistant Palmer amaranth.

Eric Prostko | Jan 15, 2019

As my colleague and I began our annual weed science gospel tour earlier this year, it was interesting that both of our presentations partially focused on the management of Benghal dayflower/tropical spiderwort (BD/TSW).

We did not consult each other prior to the tour and this was an obvious reflection of the number of inquiries we received about this weed in 2018.  As you might recall, BD/TSW was PUBLIC ENEMY NO. 1 prior to the evolution of herbicide-resistant Palmer amaranth in most of the southeast.  Since BD/TSW reared its ugly head again in 2018, I thought it might be a great time to review what happened and how this weed can be managed in peanuts.

It is my opinion that BD/TSW was such a problem in 2018 because of the biblical rainfall that occurred.  Here on the UGA-Tifton Campus where I reside, the rainfall total for the year was 62.77” (15.4” above the long-term average)!  Under soggy conditions, BD/TSW plants tend to grow very well, residual herbicides do not last as long, and timely POST herbicide applications can be delayed.  This trifecta is a great recipe for a BD/TSW nightmare.  Now I have no influence over the weather, but I do have a few suggestions for control that might be helpful.

Much like Palmer amaranth seed, BD/TSW seed does not like to be buried.  This is why tillage with a moldboard plow is so helpful in the management of this weed.  Research has shown that BD/TSW seed buried deeper than 4” in the soil will likely not emerge at all.  Other research has shown that BD/TSW seed viability is reduced to near 0% when buried 8” deep for at least three years.

I know that some folks prefer strip tillage to conventional tillage for very important economic and environmental reasons, but UGA research in 2018 continued to show that conventional-tillage peanuts out yielded strip-till peanuts by 8.6% to 13.3%, depending upon row configuration (single or twin row).

Over the last several years, there has been some discussion on the continued need for twin-row peanuts with the development of newer, disease-resistant, and high-yielding cultivars.   That cerebral discussion might be above my pay grade.  However, I can say that BD/TSW control in twin rows is about 12% better than in single rows.  Also, do not forget that twin rows are very important in the management of tomato spotted wilt virus.

The use of multiple applications of residual herbicides (at least two apps) prior to BD/TSDW emergence is crucial for full-season control.  Historically, Dual Magnum (s-metolachlor) has been the residual herbicide of choice for BD/TSW, but other relatively new peanut herbicides are available including Warrant (acetochlor) and Zidua (pyroxasulfone).

POST herbicide options for BD/TSW control in peanuts include Basagran (bentazon), Cadre (imazapic), Gramoxone (paraquat), and Strongarm (diclosulam).

Do not forget that the peak emergence of BD/TSW in South Georgia is around June 1.  Thus, at-planting applications of Dual Magnum or Warrant with April sowed peanuts might not be the best place for these residuals.  I tend to prefer BD/TSW residuals in combination with “cracking” Gramoxone sprays AND later POST herbicide applications (2 apps of residuals).

Mother Nature is very fickle and can be either friend or foe.  That’s entirely up to her.  All you can do is be prepared.  Didn’t someone more famous than I say “luck or chance favors the prepared”?  As with most weed problems, the best approach for managing BD/TSW in peanuts is to use a combination of tactics, including tillage, row spacing, multiple applications of residual herbicides, and timely POST herbicide applications.

As always, good weed hunting!

iita correct


Plant health covers topics such as the safe handling and movement of germplasm and seed, as well as the range of biotic threats faced by crops and the ways they can be managed to optimise yields and ensure safety and quality in crop production. These threats include viral, bacterial and fungal diseases as well as the impact of insect pests and weeds. This collection summarises 50 years of research on plant health by the International Institute of Tropical Agriculture (IITA) to improve the health of crops in Africa.

The first part of the book reviews general issues such as pest and disease surveillance and the range of viruses affecting key African crops. Part 2 summarises key research on improving the health of major crops such as cassava, maize, yams and cocoyams, bananas and plantains, legumes, vegetables and tree fruits. The final part of the book discusses ways of improving integrated pest management of insect pests, diseases and weeds in sub-Saharan Africa.

This unique book brings together some of the world’s leading experts on plant health in sub-Saharan Africa to review progress in dealing with the range of biotic threats faced by African farmers, and will be a standard reference on improving the management of pests and diseases in developing countries.

Key features

·         Focuses on plant health issues in sub-Saharan Africa which are key to improving yields

·         Reviews ways of improving the health of key African crops such as cassava, maize and grain legumes

·         Brings together leading experts on plant health in sub-Saharan Africa

What others are saying…

“This book, a must read for international agricultural scientists and pest management specialists, describes in meticulous detail how a group of eminent scientists have dedicated their lives to produce research that has led to stunning breakthroughs in the development of pest management strategies designed to solve the problems of African food insecurity, hunger and poverty.” Professor E. A. “Short” Heinrichs, Secretary General – International Association for the Plant Protection Sciences

Table of contents

Part 1 Managing threats to plant health
1.Key challenges in plant health in sub-Saharan Africa: stakeholder priorities: Kenton Dashiell, IITA, Nigeria;
2.Introduction to critical issues in plant health: a 50-year retrospective on African agriculture: Peter Neuenschwander and Manuele Tamò, IITA, Benin;
3.Disease surveillance, diagnostics and germplasm health in crop protection: P. Lava Kumar, IITA, Nigeria; J. P. Legg, IITA, Tanzania; M. Ayodele, IITA, Nigeria; G. Mahuku, IITA, Tanzania; and A. Ortega-Beltran and R. Bandyopadhyay, IITA, Nigeria;
4.Conserving and exploiting biodiversity in crop cultivation in sub-Saharan Africa: Georg Goergen and Peter Neuenschwander, IITA, Benin; and Danny Coyne, IITA, Kenya;
5.Viruses and their vectors in sub-Saharan African crops: James Legg, IITA, Tanzania, P. Lava Kumar, IITA, Nigeria; George Mahuku and Everlyne Wosula, IITA, Tanzania; Livia Stavolone, IITA, Nigeria; Eugene Terry, New Markets Lab, USA; and Nilsa Bosque-Pérez, University of Idaho, USA;

Part 2 Plant health in practice: managing threats to key African crops
6.Identifying and managing plant health risks for key African crops: cassava: M. Toko and P. Neuenschwander, IITA, Benin; J. S.Yaninek, Purdue University, USA; A. Ortega-Betran, IITA, Nigeria; A. Fanou and V. Zinsou, Université de Parakou, Benin; K. Wydra, Erfurt University of Applied Sciences, Germany; R. Hanna and A. Fotso, IITA, Cameroon; and O.K. Douro-Kpindou, IITA, Benin;
7.Identifying and managing plant health risks for key African crops: maize: Ranajit Bandyopadhyay, IITA, Nigeria; Kitty F. Cardwell, Oklahoma State University, USA; Alejandro Ortega-Beltran, IITA, Nigeria; Fritz Schulthess, Rheinstrasse 160, Switzerland; William Meikle, USDA-ARS, USA; Mamoudou Sétamou, Texas A&M University, USA; and Peter J. Cotty, USDA-ARS, USA;
8.Identifying and managing plant health risks for key African crops: yam, taro and cocoyam: Babatima Djana Mignouna, IITA, Benin; P. Lava Kumar, IITA, Nigeria; Danny Coyne, IITA, Kenya; and Ranajit Bandyopadhyay, Alejandro Ortega-Beltran, Ranjana Bhattacharjee and David De Koeyer, IITA, Nigeria;
9.Identifying and managing plant health risks for key African crops: banana and plantain: Stefan Hauser, IITA, Nigeria; C. Clifford Gold, International Agriculture Consultant, USA; Cornelia Pasberg-Gauhl and Friedhelm Gauhl, Consulting Office for Agriculture, Austria; Juliet Akello, IITA, Zambia; Kim Jacobsen, Royal Museum for Central Africa, Belgium; Lindsey Norgrove, Bern University of Applied Sciences, Switzerland; Daniel Coyne, IITA, Kenya; P. Lava Kumar, IITA Tanzania; George Mahuku, Manoj Kaushal and Valentine Nakato, IITA, Tanzania; and Leena Tripathi and Jaindra Tripathi, IITA, Kenya;
10.Identifying and managing plant health risks for key African crops: legumes: M. Tamò, IITA, Benin; L. Afouda, Université de Parakou, Benin; R. Bandyopadhyay, IITA, Nigeria; H. Bottenberg, United States Agency for International Development, USA; L. Cortada-Gonzales, IITA, Kenya; H. Murithi, IITA, Tanzania; A. Ortega-Beltran, IITA, Nigeria; B. Pittendrigh, Michigan State University, USA; R. Sikirou, Institut National des Recherches Agricoles au Bénin, Benin; A. Togola, IITA, Nigeria; and K.D. Wydra, Erfurt University of Applied Sciences, Germany;
11.Identifying and managing plant health risks for key African crops: vegetables: I. Godonou, IITA and Catholic University of West Africa, Benin; M.-G. Sæthre, IITA, Nigeria; G. Tepa-Yotto, IITA and Université Nationale d’Agriculture, Benin; D. Gnanvossou and O.K. Douro Kpindou, IITA, Benin; and D. Coyne, IITA, Kenya;
12.Identifying and managing plant health risks for key African crops: fruit and other tree crops: P. Neuenschwander and D. Gnanvossou, IITA, Benin; S. Hauser, IITA, Nigeria; G. Goergen, IITA, Benin; R. Hanna, IITA, Cameroon; L. Norgrove, Bern University of Applied Sciences, Switzerland; and K. Negloh and C. Agboton, IITA, Benin;

Part 3 – Integrated pest management: putting it all together and exchange of knowledge with farmers
13.Commercial products promoting plant health in African agriculture: Frederick Schreurs and Ranajit Bandyopadhyay, IITA, Nigeria; Christiaan Kooyman, IITA, Kenya; Alejandro Ortega-Beltran and Adebowale Akande, IITA, Nigeria; Matieyedou Konlambigue, IITA, Ghana; Niels Van den Bosch, IITA, Nigeria;
14.Weeds affecting crops in sub-Saharan Africa: David Chikoye, IITA, Zambia; Friday Ekeleme, Stefan Hauser, Abebe Menkir and Alpha Y. Kamara, IITA, Nigeria; Peter Neuenschwander and Obinna Ajuonu, IITA, Benin; and Hakeem A. Ajeigbe, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Nigeria;
15.Integrated pest management (IPM) for crops in sub-Saharan Africa: Danny Coyne, IITA, Kenya; Michael Abberton, IITA, Nigeria; Sounkoura Adetonah, IITA, Benin; Maria Ayodele, IITA, Nigeria; Laura Cortada, IITA, Kenya; Brice Gbaguidi, IITA, Benin; Stefan Hauser and P. Lava Kumar, IITA, Nigeria; Peter Neuenschwander, IITA, Benin; Marc Schut, IITA, Rwanda and Wageningen University, The Netherlands; Manu Tamò, IITA, Benin; and Abou Togola, IITA, Nigeria;

Part 4 – Conclusions and future challenges
16.Conclusions and future challenges; Peter Neuenschwander, IITA, Benin;

IAPPS | January 17, 2019 at 10:54 pm | Categories: Uncategorized | URL: https://wp.me/pWoIf-43E

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New book from CABI

A History of Pesticides

Graham A Matthews, Emeritus Professor, Imperial College London, UK

 In this fascinating book, Graham Matthews takes the reader through the history of the development and use of chemicals for control of pests, weeds, and vectors of disease.

Prior to 1900 only a few chemicals had been employed as pesticides but in the early 1940s, as the Second World War raged, the insecticide DDT and the herbicide 2-4-D were developed. These changed everything. Since then, farmers have been using a growing list of insecticides, herbicides and fungicides to protect their crops. Their use has undoubtedly led to significant gains in agricultural production and reduction in disease transmission, but also to major problems: health concerns for both users of pesticides and the general public, the emergence of resistance in pest populations, and environmental problems.

The book examines the development of legislation designed to control and restrict the use of pesticides, the emergence of Integrated Pest Management (IPM) and the use of biological control agents as part of policy to protect the environment and encourage the sustainable use of pesticides.

Finally, the use of new technologies in pest control are discussed including the use of genetic modification, targeted pesticide application and use of drones, alongside basic requirements for IPM such as crop rotations, close seasons and adoption of plant varieties with resistance to pests and diseases.

Key Features • A fascinating look at the history of pesticides from the earliest times right up to the present day • The book covers changes in application technology as well as the chemicals themselves • Includes a discussion on the application of new technologies in pest management • Discusses major issues surrounding pesticides and their future role in food production and disease control with a growing human population

Audience Suitable for students of crop protection and pest management specialists, scientists working in the pesticides industry, countryside managers, members of NGOs and environmental campaign groups, conservationists and amateur naturalists.

Contents 1: Pesticides in the early part of the 20th Century 2: Application of Pesticides 3: Insecticides 1950 onwards 4: Herbicides 5: Fungicides 6: Other Pesticides 7: Resistance 8: Integrated Pest Management 9: Health Issues 10: Regulations and the manufacturers of pesticides and related organisations 11: Pesticides – The Future

science daily

Furloughed from his work on rocket tests, NASA contractor Jack Lyons spends time in his workshop making props for marching bands.

David Goldman/AP Photo

No pay. No retirement. No stink bugs by mail. The shutdown pain is spreading

No paychecks. No experiments. No reviews of grant applications. And no stink bugs by mail.

The financial, empirical, and entomological consequences of the partial shutdown of the U.S. government for science multiplied this week, as it became the longest such closure in history. More than a half-dozen agencies that fund or conduct research, including NASA, the National Science Foundation (NSF), the U.S. Department of Agriculture (USDA), and the Food and Drug Administration (FDA), have been partly paralyzed since 22 December 2018. And the fight between Congress and President Donald Trump over spending $5.7 billion on a border wall, which has shuttered about one-quarter of the federal government, shows no signs of being resolved.

The impasse has already meant a lost paycheck for some 800,000 federal employees, as well as missed payments for thousands more contractors and academic researchers. Agencies have canceled dozens of meetings to review thousands of funding proposals, at one of the busiest times for federal grantmaking. Researchers inside and outside of government have postponed, restructured, or just given up entirely on planned studies.

The shutdown could soon paralyze federally funded scientific facilities and research centers that have been largely insulated from the pain because they are operated by contractors who get paid in advance, often on a quarterly basis. “But now that quarterly check may or may not be coming,” says Benjamin Corb, public affairs director at the American Society for Biochemistry and Molecular Biology in Rockville, Maryland. “The uncertainty is creating a real mess.”

At the National Center for Atmospheric Research in Boulder, Colorado, which is funded by NSF but operated by a consortium of universities, managers are beginning to consider ways to scale back activities. Staff could be given the option of being furloughed without pay or continuing to work at reduced pay (with back pay once the shutdown ends). That could disrupt efforts to improve climate models and manage massive data sets, officials say.

NSF’s closure is also creating anxiety for would-be graduate students hoping to win a prestigious Graduate Research Fellowship (GRF) from the agency. Last year, the agency received more than 12,000 GRF applications and gave out 2000 awards, which provide graduate students with a $34,000 annual stipend for 3 years. Managing that massive operation requires sticking to a tight schedule. Some 2000 reviewers had already agreed to serve on about four dozen virtual panels set for later this month. But if NSF remains closed, those panels will not be able to meet. (The agency had already canceled 33 other proposal review meetings as of 14 January, according to Corb.)

NSF typically announces GRF winners by the beginning of April because U.S. graduate schools require accepted students to make a firm decision by 15 April. So far, the agency has no contingency plan in case its review process is delayed. “Nobody knows what will happen because there’s been no guidance,” says a former GRF program manager who requested anonymity.

At FDA, reviews of submitted drugs and devices already paid for by industry fees can continue. But some researchers who want to continue other work—developing new tools or methods for evaluating drugs, for example—must show that it is essential for health, safety, or protecting a federal investment (such as continuing an animal experiment that has already begun). The justification process is “a heavily scrutinized rigmarole,” says one FDA employee who asked to remain anonymous.

Agricultural research is taking a particularly heavy hit because it often involves collaborations between federal and private or academic laboratories. At the Virginia Polytechnic Institute and State University in Blacksburg, veterinary pathologist Kevin Lahmers has had to halt studies aimed at evaluating the livestock disease threat posed by the Asian longhorned tick, first discovered in the United States in 2017. He is collaborating with a USDA laboratory in Pullman, Washington, to determine whether the tick can help transmit a parasite between calves, but the lab is closed. The disruption “will handicap our understanding of the disease,” Lahmers said in a statement.

At a USDA research center in Montana, the closure has wrecked a 3-month-long experiment that was to be one researcher’s final act before retiring. The study, of how a fungi that grows on wheat might be used to defend the plants against pest insects, “was to be my ‘swan song,’” says entomologist Stefan Jaronski of the Northern Plains Agricultural Research Laboratory in Sidney. He expected to spend this week cleaning out his laboratory before retiring on 18 January after a more than 35-year career, including about 19 years at USDA. But now it isn’t clear whether the department can complete his exit paperwork. And his final experiment, which Jaronski was conducting with a collaborator from the nation of Georgia, is “down the tubes” because he hasn’t been able to collect data needed “not only for good science, but publishing.”

USDA entomologist Don Weber, who works on biocontrol agents at the department’s Beltsville Agricultural Research Center in Maryland, isn’t completely immobilized. He is allowed to enter his lab a few times a week to maintain insect and plant populations. But he can’t do studies. Nor can he mail invasive stink bugs from his colonies to other researchers who want them, hobbling efforts to find a defense against the growing farm pest. And Weber hasn’t been able to order a synthesized chemical that is key to an upcoming project because his contract office is closed. “I’m going to lose a field season,” he predicts.

Weber hasn’t let past closures derail his research. During a 16-day funding impasse in 2013, he went ahead and collected the final data in a long-term field study “in defiance of the shutdown,” he acknowledged in a 2014 paper. “The way I saw it,” Weber says now, “collecting that data was essential to protecting a federal investment. Otherwise, the money that had been spent would have gone to waste.”

With reporting by Jeffrey Mervis and Kelly Servick.

Pest lens


About PestLens

Thursday, January 17, 2019 Notification

PestLens Survey
We invite you to complete our brief anonymous survey, so we might better serve you. This survey should take about 5-10 minutes to complete. Your comments and suggestions are important to us. Please use the following link to access the survey: https://www.surveymonkey.com/r/PestLens. Thank you for your participation!

First report of the begomovirus Mungbean yellow mosaic India virus (MYMIV) infecting Solanum lycopersicum (tomato) and Cucumis sativus (cucumber)
Source: Plant Disease, Australasian Plant Pathology
Event:  New Host

Recently, Cucumis sativus (cucumber) plants in a greenhouse in Oman exhibited yellow leaf mosaic and crumpling. Additionally, during 2016 surveys, cultivated Solanum lycopersicum (tomato) plants in India exhibited leaf curl and mosaic. Molecular analyses confirmed that the causal agent in each case was the begomovirus Mungbean yellow mosaic India virus (MYMIV). These are the first reports of MYMIV infecting Cucumis sativus and S. lycopersicum.

MYMIV infects other economically important plants, including Glycine max (soybean), Phaseolus vulgaris (bean), Vigna spp. (cowpea), and Cucurbita pepo (pumpkin). MYMIV has been reported from Oman and parts of Asia and is not known to occur in the United States. MYMIV is transmitted by the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae), which occurs in the United States. The PEST ID database does not list MYMIV (queried 1/16/19).


  1. Shahid, M. S., I. H. Al-Mahmooli, A. M. Al-Sadi, and R. W. Briddon. 2018. Identification of Mungbean yellow mosaic India virus infecting cucumber in Oman. Plant Disease 102(2):465. Last accessed January 17, 2019, from https://apsjournals.apsnet.org/doi/full/10.1094/PDIS-09-17-1356-PDN.
  2. Agnihotri, A. K., S. P. Mishra, M. Ansar, R. C. Tripathi, R. Singh, and M. Akram. 2019. Molecular characterization of Mungbean yellow mosaic India virus infecting tomato (Solanum lycopersicum L.). Australasian Plant Pathology DOI: 10.1007/s13313-018-0611-7. Last accessed January 17, 2019, from https://link.springer.com/content/pdf/10.1007%2Fs13313-018-0611-7.pdf.
  3. Pandey, J. and N. Verma. 2017. First report of Mungbean yellow mosaic India virus infecting pumpkin in India. New Disease Reports 36:23. Last accessed January 17, 2019, from https://www.ndrs.org.uk/pdfs/036/NDR_036023.pdf.

If you have any questions or comments for us about this article, please e-mail us at PestLens@aphis.usda.gov or log into the PestLens web system and click on “Contact Us” to submit your feedback.

First report of the slug Semperula wallacei (Gastropoda: Veronicellidae) in Japan
Source: BioInvasions Records
Event:  New Location

Recently, the slug Semperula wallacei (Gastropoda: Veronicellidae) was collected in Japan. This is the first report of S. wallacei in Japan.

Semperula wallacei is a polyphagous plant pest. It has also been reported from other parts of Asia, Oceania, and the United States, where it has been reported from American Samoa. Veronicellid slugs are intermediate hosts of Angiostrongylus cantonensis (rat lungworm), the causal agent of angiostrongyliasis. The PEST ID database lists Semperula wallacei as reportable (queried 1/16/19).


  1. Hirano, T., D. Yamazaki, S. Uchida, T. Saito, and S. Chiba. 2018. First record of the slug species Semperula wallacei (Issel, 1874) (Gastropoda: Eupulmonata: Veronicellidae) in Japan. BioInvasions Records 8. Last accessed January 17, 2019, from http://www.reabic.net/journals/bir/2019/Accepted/BIR_2019_Hirano_etal_correctedproof.pdf.

If you have any questions or comments for us about this article, please e-mail us at PestLens@aphis.usda.gov or log into the PestLens web system and click on “Contact Us” to submit your feedback.

First report of starhorn, Hygrophila corymbosa (Scrophulariales: Acanthaceae), naturalized in Mexico
Source: BioInvasions Records
Event:  Naturalization

Since 2007, populations of the aquatic weed starhorn, Hygrophila corymbosa (Scrophulariales: Acanthaceae), have been observed in irrigation canals in Mexico. This is the first report of H. corymbosa naturalized in Mexico.

Hygrophila corymbosa is native to India, Myanmar, Indonesia, and Malaysia. It is naturalized in Hungary, Taiwan, and the United States, where it occurs in two counties in Florida. Hygrophila corymbosa reproduces from seed and stem fragments, grows quickly, and forms monocultures that can reduce native species diversity. It is cultivated ornamentally in aquaria.


  1. Mora-Olivo, A., L. A. Alvarez-Vazquez, G. N. Requena-Lara, L. U. Arellano-Méndez, and H. A. Garza-Torres. 2018. New record of Hygrophila corymbosa (Blume) Lindau (Acanthaceae) for Mexico, a highly invasive aquatic weed. BioInvasions Records 7(4):375-379. Last accessed January 17, 2019, from http://www.reabic.net/journals/bir/2018/4/BIR_2018_Mora-Olivo_etal.pdf.
  2. Lukács, B. A., A. Mesterházy, R. Vidéki, and G. Király. 2014. Alien aquatic vascular plants in Hungary (Pannonian ecoregion): Historical aspects, data set and trends. Plant Biosystems 150(3):388-395. Last accessed January 17, 2019, from https://www.tandfonline.com/doi/pdf/10.1080/11263504.2014.987846?needAccess=true.

If you have any questions or comments for us about this article, please e-mail us at PestLens@aphis.usda.gov or log into the PestLens web system and click on “Contact Us” to submit your feedback.

New trichovirus, peach chlorotic leaf spot virus, described from China
Source: Archives of Virology
Event:  New Description/Identification

A recent publication describes a new trichovirus, peach chlorotic leaf spot virus, isolated from Prunus persica (peach) trees in China. Affected trees exhibited leaf chlorosis and mosaic.


  1. Zhou, J., Z. Zhang, M. Lu, H. Xiao, N. Habili, and S. Li. 2018. Complete nucleotide sequence of a new virus, peach chlorotic leaf spot virus, isolated from flat peach in China. Archives of Virology DOI: 10.1007/s00705-018-3984-6. Last accessed January 17, 2019, from https://link.springer.com/content/pdf/10.1007%2Fs00705-018-3984-6.pdf.

If you have any questions or comments for us about this article, please e-mail us at PestLens@aphis.usda.gov or log into the PestLens web system and click on “Contact Us” to submit your feedback.

To access previous PestLens articles, please log into PestLens.


Dear Colleague,

Greetings from the Secretariat of the “1st International Molecular Plant Protection Congress, IMPPC-2019”! We have almost 3 months left for the start of IMPPC-2019. We will be hosting 42 keynote speakers from 17 different countries (please see attached congress flier). We would like to kindly remind you that abstract submission deadline is Jan 21, 2019.

Please upload your abstract at:


Please follow the instructions when preparing your abstract:


Please do not forget to register for your self and accompanying persons (if any) at:


For accommodation:

We look forward to meeting you in Adana!
Kind Regards,
IMPPC-2019 Organization Committee

Puerto Rico: Insect collapse


Insect collapse: ‘We are destroying our life support systems’

Scientist Brad Lister returned to Puerto Rican rainforest after 35 years to find 98% of ground insects had vanished

El Yunque national forest in Sierra de Luquillo, Puerto Rico
El Yunque national forest in Sierra de Luquillo, Puerto Rico. Photograph: Stuart Westmorland/Corbis/Getty Images

“We knew that something was amiss in the first couple days,” said Brad Lister. “We were driving into the forest and at the same time both Andres and I said: ‘Where are all the birds?’ There was nothing.”

His return to the Luquillo rainforest in Puerto Rico after 35 years was to reveal an appalling discovery. The insect population that once provided plentiful food for birds throughout the mountainous national park had collapsed. On the ground, 98% had gone. Up in the leafy canopy, 80% had vanished. The most likely culprit by far is global warming.

“It was just astonishing,” Lister said. “Before, both the sticky ground plates and canopy plates would be covered with insects. You’d be there for hours picking them off the plates at night. But now the plates would come down after 12 hours in the tropical forest with a couple of lonely insects trapped or none at all.”

“It was a true collapse of the insect populations in that rainforest,” he said. “We began to realise this is terrible – a very, very disturbing result.”

The El Yunque national forest

The El Yunque national forest. Photograph: Alisha Bube/Getty Images

Earth’s bugs outweigh humans 17 times over and are such a fundamental foundation of the food chain that scientists say a crash in insect numbers risks “ecological Armageddon”. When Lister’s study was published in October, one expert called the findings “hyper-alarming”.

The Puerto Rico work is one of just a handful of studies assessing this vital issue, but those that do exist are deeply worrying. Flying insect numbers in Germany’s natural reserves have plunged 75% in just 25 years. The virtual disappearance of birds in an Australian eucalyptus forest was blamed on a lack of insects caused by drought and heat. Lister and his colleague Andrés García also found that insect numbers in a dry forest in Mexico had fallen 80% since the 1980s.

“We are essentially destroying the very life support systems that allow us to sustain our existence on the planet, along with all the other life on the planet,” Lister said. “It is just horrifying to watch us decimate the natural world like this.”

It was not insects that drew Lister to the Luquillo rainforest for the first time in the mid-1970s. “I was interested in competition among the anoles lizards,” he said. “They’re the most diverse group of vertebrates in the world and even by that time had become a paradigm for ecology and evolutionary studies.”

La Mina river cascades over rocks in El Yunque national forest

La Mina river in El Yunque national forest. Photograph: Raul Touzon/NG/Getty Images

The forest immediately captivated Lister, a lecturer at Rensselaer Polytechnic University in the US. “It was and still is the most beautiful forest I have ever been in. It’s almost enchanted. There’s the lush verdant forest and cascading waterfalls, and along the roadsides there are carpets of multicoloured flowers. It’s a phantasmagoric landscape.”

It was important to measure insect numbers, as these are the lizards’ main food, but at the time he thought nothing more of it. Returning to the national park decades later, however, the difference was startling.

“One of the things I noticed in the forest was a lack of butterflies,” he said. “They used to be all along the roadside, especially after the rain stopped, hundreds upon hundreds of them. But we couldn’t see one butterfly.”

Since Lister’s first visits to Luquillo, other scientists had predicted that tropical insects, having evolved in a very stable climate, would be much more sensitive to climate warming. “If you go a little bit past the thermal optimum for tropical insects, their fitness just plummets,” he said.

As the data came in, the predictions were confirmed in startling fashion. “The number of hot spells, temperatures above 29C, have increased tremendously,” he said. “It went from zero in the 1970s up to something like 44% of the days.” Factors important elsewhere in the world, such as destruction of habitat and pesticide use, could not explain the plummeting insect populations in Luquillo, which has long been a protected area.

Data on other animals that feed on bugs backed up the findings. “The frogs and birds had also declined simultaneously by about 50% to 65%,” Lister said. The population of one dazzling green bird that eats almost nothing but insects, the Puerto Rican tody, dropped by 90%.

A Puerto Rican tody

A Puerto Rican tody. Photograph: W arissen/Getty Images

Lister calls these impacts a “bottom-up trophic cascade”, in which the knock-on effects of the insect collapse surge up through the food chain.

“I don’t think most people have a systems view of the natural world,” he said. “But it’s all connected and when the invertebrates are declining the entire food web is going to suffer and degrade. It is a system-wide effect.”

To understand the global scale of an insect collapse that has so far only been glimpsed, Lister says, there is an urgent need for much more research in many more habitats. “More data, that is my mantra,” he said.

The problem is that there were very few studies of insect numbers in past decades to serve as a baseline, but Lister is undeterred: “There’s no time like the present to start asking what’s going on.”