Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Clay-clad corpses kill crop pests

21.05.2002


Pellets of rotting moths could keep weevils off oranges.


All wrapped up: dead moths make slow-release anti-pest pellets.
© US Dep. Agriculture


Fresh from a corpse, worms are more infective.
© © US Dep. Agriculture



Mummified rotting cadavers could be a cost-effective way to combat soil pests, suggest scientists at the US Department of Agriculture. Citrus crops, cranberries and ornamental shrubs all stand to benefit.

Bacteria in the guts of roundworms grown inside dead wax moths can emerge to kill other soil insects, including the black vine weevil (Otiorhynchus sulcatus), a serious pest of plants in nurseries.


The USDA’s Southeastern Fruit and Tree Nut Research Laboratory in Byron, Georgia, is coating dead moths in clay and starch to turn them into slow-release anti-pest pellets. One of these biological time bombs could keep a potted plant pest-free for months.

"Using cadavers means you don’t waste time or money harvesting roundworms," says Ed Lewis, who studies insects at Virginia Polytechnic Institute and State University in Blacksburg, Virginia. Wax moths are readily available and cheap: they are already commercially bred for fish bait.

Citrus farmers currently spray their fields with water containing roundworms, properly called nematodes. These worms are either grown in moth cadavers and captured in a water bath or raised in artificial media.

"Worms fresh out of a cadaver are 10 times more infective than those developed in artificial media," says David Shapiro-Ilan, a member of the USDA team. A chemical in the cadaver is believed to increase their infectivity.

Previous trials of ’dead body delivery’ floundered because of the corpses’ lack of structural integrity. Like most rotting things, they fell apart before reaching the greenhouse or field.

The new clay casing keeps the bloated cadavers together until soil water dissolves it. Then tens of thousands of nematodes slowly crawl out. When the worms (Heterorhabditis bacteriophora) enter soil pests through the mouth or anus, their resident bacteria (Photorhabdus luminescens) emerge and produce insecticidal proteins.

Farmers and nurserymen will probably need to lay down pellets quite frequently as the distribution of nematodes is patchy, and they can disappear within weeks.

Field trials are underway, and have already captured the interest of industry. The researchers have signed an agreement with H&T Alternative Controls in Perry, Georgia, to produce the nematodes and infected cadavers.

Nematodes aren’t often thought of as soil’s good guys. Some are themselves pests, infecting the roots of many commercial crops. Most are benign but important parts of the soil’s food web. Roughly 30 of the 25,000 known species are heralded for the insecticidal abilities of their associated bacteria.

VIRGINIA GEWIN | © Nature News Service

More articles from Agricultural and Forestry Science:

nachricht Back to Nature: Palm oil plantations are being turned back into protected rainforest
21.03.2019 | Forschungsverbund Berlin e.V.

nachricht The inner struggle of the evening primrose: Chloroplasts are caught up in an evolutionary arms race
14.03.2019 | Max-Planck-Institut für Molekulare Pflanzenphysiologie

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Solving the efficiency of Gram-negative bacteria

22.03.2019 | Life Sciences

Bacteria bide their time when antibiotics attack

22.03.2019 | Life Sciences

Open source software helps researchers extract key insights from huge sensor datasets

22.03.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>