Pesticide Sprays Improve Food Safety

Cherry Fruit Fly

Cherry Fruit Fly

Plants are living, dynamic organisms that must defend themselves from bacteria, fungi and insects. Plants in nature synthesize toxic chemicals in large amounts as a primary defense against hordes of bacterial, fungal, and insect predators. Plants respond to attacks by increasing their production of self-defense chemistries. To be effective, these self-defense chemistries are often potent toxicants. The good news is that the levels of natural toxicants of food plants are very much under human control through the application of small amounts of man-made pesticides. Farmers treat crops with pesticides to reduce damage from insects and fungi. When plants do not have to fight off insects and fungi, the plants make less of the self-defense chemicals. Adding a tiny amount of synthetic pesticide reduces exposure to larger amounts of plant-produced toxic chemicals.

“An unrecognized benefit of use of crop protection chemicals is a reduced net exposure to toxicants. …crops that are stressed by competition from weeds, and from attack from infections and bugs, have increased levels of ‘natural’ pesticides. Crops protected from stress have smaller amounts of ‘natural’ pesticide. These ‘natural’ pesticides commonly are mutagenic and carcinogenic, as well as having the capability of inducing a large variety of other types of toxicities. Manufactured crop-protection chemicals are screened for mutagenicity, carcinogenicity, organ toxicity and the like, and exposure is rigorously regulated. Hence, proper use of crop-protection chemicals can cause a net reduction in toxicant exposure by reducing exposure to the potentially more hazardous and abundant ‘natural’ pesticides.”

Author: Mattsson, J. L.
Affiliation: Health and Environmental Sciences, The Dow Chemical Co.
Title: Let’s end the double standard for natural versus manufactured chemicals
Source: J Occup Health. 1996. 38:94-96.

30 million Insects per Acre in Chinese Rice Fields Means Growers Must Spray

Rice Stripe on Leaf

Rice Stripe on Leaf

Insects often transmit diseases when they fed on a crop plant. Rice is fed on by planthoppers which transmit viruses. In one outbreak in China, 30 million planthoppers were estimated to infest each of 50 million acres. Major losses were prevented thanks to insecticide sprays.

“Laodelphax striatellus Fallén (Hemoptera: Delphacidae) is an economically important sap-sucking pest in rice. The leaves infested by L. striatellus turn yellow, wilt, and even die, resulting in yield loss and quality reduction. In addition, L. striatellus transmits rice viral diseases such as Rice black-streaked dwarf virus and Rice stripe virus, which are two of the most serious diseases and often cause major yield losses. In recent years, the damage caused by L. striatellus feeding injury and the diseases transmitted by this planthopper has been increasing in China. When the outbreak occurred in Jiangsu and Anhui provinces in 2004 and 2005, the density of L. striatellus reached 30 million per acre, and 50 million acres of rice was infested, causing 30% of yield reduction in areas without pesticide treatment.”

Authors: C-X Duan1, J-M Wan1, H-Q Zhai2, Q Chen1, J-K Wang1, N Su1 and C-L Lei1
Affiliation:
1Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China; 2Chinese Academy of Agricultural Sciences, Beijing, China
Title: Quantitative trait loci mapping of resistance to Laodelphax striatellus (Hemoptera: Delphacidae) in rice using recombinant inbred lines.
Publication: Journal of Economic Entomology. 2007. 100(4):1450-1455.

Japanese Consumers Have High Standards for Rice Quality Making Insecticide Use Necessary

Damaged Rice

Damaged Rice

Rice Bug

Rice Bug

The feeding of rice bugs on rice plants results in black marks on the rice grains. Japanese consumers demand perfect rice, which means that farmers must prevent the insects from feeding.

“A complex of Hemiptera, commonly referred to as rice bugs, are considered to be important insect pests in rice-growing regions of the world. Many species of Hemiptera, from families including Alydidae, Pentatomidae, Coreidae, and Miridae, have been reported as rice bugs.”

“Rice bugs cause yield loss, decrease the quality of grain, and reduce the germination rate. Among these problems, decrease in the quality of grain is considered to be the most important problem in Japanese rice. Infestations cause brown or black marks on the grain. Contamination of as little as 0.1% of such stained grain has reduced commercial value according to Japanese rice quality regulations, and thus the economic injury level is very low. This has led rice farmers to a dependence on insecticide use for rice bug control.”

Authors: H. Takeuchi1,2 and T. Watanabe1
Affiliation: 1Department of Entomology and Nematology, National Agricultural Research Center, Tsukuba, Japan; 2National Agricultural Research Center for Kyushu Okinawa Region, Kumamoto, Japan.
Title: Mortality factors of eggs of Leptocorisa chinensis (Hemiptera: Alydidae) in rice fields.
Publication: Journal of Economic Entomology. 2006. 99(2):366-372.

Insect Saliva Lowers the Quality of Italian Bread Wheat

Damaged Grain

Damaged Grain


Sunn Pest

Sunn Pest

Italian bread dough is famous for its high quality. Several insect species feed on the wheat plants in the field and when they do, they leave a little saliva behind, which would lower the quality of the bread if insecticides aren’t used.

“Several species known as sunn pests or cereal bugs, have long been recognized as detrimental to wheat bread-making quality in south central Europe, western Asia, and northern Africa. … In Italy, severe infestations of sunn pests have been reported in southern regions and also, although seldom, in the Po Valley.”

“For a long time, it has been recognized that damaged grains can show a discolored area around the point of stylet penetration and that flour derived from damaged kernels produces sticky dough and poor bread. The detrimental effect on baking quality is obvious even in presence of 3-5% damaged kernels and dramatically increases for values higher than 10%. The quality depletion is due to proteolytic enzymes injected in the kernels by insects via their saliva that persist in the flour after milling and cause breakdown of gluten structure in the dough.”

“Presently, no sources of resistance to E. Maura in Italian germplasm are known; thus the only way of reducing the damage is chemical pest control in the field.”

Authors: P. Vaccino1, M. Corbellini1, G. Reffo1, G. Zoccatelli2
, M. Migliardi3 and L. Tavella3
Affiliation: 1Instituto Sperimentale per la Cerealicoltura, Angelo Lodigiano, Italy; 2Dipartmento Scientifico e Tecnologico, University of Verona, Italy; 3University of Torino, Grugliasco, Italy.
Title: Impact of Eurygaster maura (Heteroptera: Scutelleridae) feeding on quality of bread wheat in relation to attack period.
Publication: Journal of Economic Entomology. 2006. 99(3):757-763.

“Organic Blueberries Don’t Come Easily”

The New York Times ran an article with this title in 2011 to inform readers why there are so few organic blueberries grown in New Jersey – “the blueberry capital of the world”. It seems that the organic blueberry growers are powerless to prevent massive feeding on their berries by insects that call New Jersey home. On the other hand, blueberry growers who use chemical insecticides are able to control the insect problem and harvest 2 to 4 times more blueberries per acre.

“New Jersey is one of the country’s top producers of blueberries, yet only a small number of farms are organic. And considering all the obstacles presented by nature, it’s not hard to see why. Insects like the root grub and the plum curculio, as well as some fungi, contribute to organic farmers’ loss of up to 50 percent of their berries a season, whereas conventional farmers may lose 5 percent or 6 percent, said Peter Oudemans, a Rutgers professor and a plant pathologist at the Philip E. Marucci Center for Blueberry and Cranberry Research in Chatsworth, Burlington County. Blueberry plants are native to New Jersey, Dr. Oudemans said, which makes them a natural food choice for native insects. ‘Planting a solid acre of organic blueberries in New Jersey is like throwing a peanut butter sandwich into a room full of kindergartners,’ said Dr. Oudemans, of Hammonton, ‘the blueberry capitol of the world,’ according to a local highway sign. ‘Everything around is going to go for them.'”

“‘We have to do twice the work of conventional growers,’ Mr. Condo [an organic grower] said. ‘It’s a lot harder and much more labor-intensive. Conventional farmers probably get around two or three thousand crates per acre. We’re lucky if we get 700 to 900.'”

Authors: Tammy La Gorce
Title: Organic blueberries don’t come easily.
Publication: The New York Times. June 17, 2011.