Fungicides Enable China to Lead in Global Production of Vegetables

Greenhouses in China

Greenhouses in China

China produces nearly half of the world’s vegetables- five times the U.S. share. China’s increase in vegetable acreage between 2000 and 2004 (5.7 million acres) exceeded the entire vegetable acreage in the United States (3.7 million acres). China’s vegetable production has grown mainly to meet domestic demand from its 1.3 billion citizens. There are over 7.3 million acres of greenhouse crops in China and the growing conditions in the greenhouses are conducive to fungal outbreaks making fungicide use necessary.

“Gray mold caused by B. cinerea has become one of the most economically important diseases, since the rapid development of greenhouse cultivation in the 1990s in eastern China. B. cinerea severely reduces the yield and quality of greenhouse vegetables such as eggplant, tomato, cucumber and pepper. Jiangsu and Zhejiang provinces are the major vegetable production regions of eastern China, where unheated plastic greenhouses have been in use since 1998. Growers depend on regular fungicide treatments approximately every 7 days from November to May, besides some cultural practices such as ventilation to control the epidemic of B. cinerea.”

Authors: Zhang, C. Q., et al.
Affiliation: School of Agriculture and Food Science, Zhejiang Forest College, China.
Title: Evolution of resistance to different classes of fungicides in Botrytis cinerea from greenhouse vegetables in eastern China.
Source: Phytoparasitica. 2009. 37:351-359.

Lychee, A Favorite Fruit of Chinese Emperors, Would be Largely Unavailable Without Fungicides

Litchi (lychee)

Litchi (lychee)

The lychee, also known as litchi, grows on a tropical and subtropical fruit tree native to southern China, Taiwan, Bangladesh and Southeast Asia, and now grown in many parts of the world. The lychee has a history and cultivation going back as far as 2000 BC. In the 1st century, fresh lychees were in such demand at the Imperial Court that a special courier service with fast horses would bring the fresh fruit from Guangdong. It was first introduced to the west in 1782. The fresh fruit has a delicate, whitish pulp with a floral smell and a fragrant, sweet flavor. Dried lychee are often called lychee nuts, though, of course, they are not a real nut. Litchi downy mildew is a devastating disease of litchi plants in China. Control of litchi downy mildew requires numerous fungicide applications.

“Litchi (Litchi chinensis Sonn.) is a tropical and subtropical fruit of high commercial value. Most litchi fruits are produced in China, India and Vietnam. In 2001, the world litchi production was approximately two million tons, and approximately 1.26 million tons were produced in China… However, the fruits are very susceptible to many diseases with significant losses in quality and yield. One of the most prevalent diseases is litchi downy blight caused by the peronosporomycete Peronophythora litchii.

P. litchii damages fruit, panicles and new shoots, causing panicle rot and withering, as well as watery brown spots on fruits which later produce snowy mildew. More than 60% of commercial losses have been reported after successive rainy and overcast days in the growing season.

The primary components of all commercial management programmes for this disease are applications of organic and/or inorganic fungicides.”

Authors: Wang, H., et al.
Affiliation: College of Plant Protection, Nanjing Agricultural University, China.
Title: Fungicide effectiveness during the various developmental stages of Peronophythora litchii in vitro
Source: Journal of Phytopathology. 2009. 157:407-412.

Rice Insect Pest Invades the World from the USA

Rice Water Weevil Larva

Rice Water Weevil Larva

The home of the rice water weevil is the southeastern US where the species feeds on
grasses in swampy areas. When rice plants were introduced into America, the
insect quickly found this new grass plant to its liking and has been feeding on
rice ever since. The weevils move into rice fields every year from nearby woods
and clumps of grass. Farmers have used insecticides since 1950 to control the
weevil populations in rice fields. The rice water weevil has spread from the
southeastern US to Louisiana, Texas, California, Japan, China and Italy where
it would decrease rice production without insecticide sprays.

“The rice water weevil, Lissorhoptrus oryzophilus, is the most destructive insect pest of rice in the United States. The insect is native to the southeastern United States but has, over the past 60 years, invaded important rice-growing areas in California, Asia and Europe and thus poses a global threat to rice production.

Small-plot research and sampling of commercial fields indicate yield losses from the rice water weevil would likely exceed 10% in many areas if no insecticides are used.”

Authors: Stout, M. J., et al.
Affiliations: Department of Entomology, Louisiana State University.
Title: The influence of rice plant age on susceptibility to the rice water weevil, Lissorhoptrus oryzophilus.
Source: Journal of Applied Entomology. 2013. 137:241-248.

Southern California Vineyards Recover Thanks to Insecticide Applications

Grapevines Destroyed in 1999

Grapevines Destroyed in 1999

Temecula Today

Temecula Today

In 1999, about one-third of the vineyards in Temecula Valley, Riverside County, California were destroyed due to Pierce’s Disease which is caused by a bacteria transmitted to grapevines by an insect-the glassy winged sharpshooter. The disease seemed destined to spread throughout Southern California. However, research demonstrated that a carefully-timed insecticide application would prevent the sharpshooter from transmitting the disease to grapevines. As a result of this insecticide use, the wine grape industry in Southern California has recovered and is prospering.

“Twelve years ago a Pierce’s disease epidemic in Southern California wine grapes prompted a multi-pronged local, state and federal attack to contain the disease spread and find a cure or treatment.

Riverside County agriculture officials declared a local emergency in 1999 and 300 acres of Temecula wine grape vines were destroyed after they were found to be infested with the glassy winged sharpshooter.

Emergencies were declared, a task force was formed, and in 2000 $22.3 million in federal financial assistance was secured to reduce pest infestations and support research.

Research found that the Southern California epidemics were almost entirely the result of vine-to-vine transmission…. A protocol of applying one carefully timed application of a persistent systemic insecticide such as imidacloprid virtually eliminates the vine-to-vine spread.

Ben Drake is a Temecula-area wine grape grower and vineyard manager who began seeing problems from PD in the Temecula Valley as early as 1997.

We’ve found that if we apply (imidacloprid) at the middle to the end of May, before the sharpshooter moves out of the citrus and goes into the vineyards, we get levels of the material into the plant high enough that when the sharpshooter flies over from the citrus groves to try it, they just fly back where they came from. Or, if they feed long enough, it will kill them.

But just look at the Temecula Valley now to understand what’s changed: From 12 wineries in 1999, the Temecula Valley Winegrowers Association website today lists more than 50 growers and 34 wineries…. A thriving agritourism industry has developed…. Existing wineries are expanding and new ones are under construction or in planning phases.”

Author: Christine Thompson
Affiliation: Reporter
Title: Grape growers urged to remain vigilant against sharpshooter pest
Source: Western Farm Press. 2011-12-12. Available at: http://westernfarmpress.com/grapes/grape-growers-urged-remain-vigilant-against-sharpshooter-pest

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.

China Warns of Famine Without Pesticides

Over the past several decades, China has become self-sufficient in basic foods such as wheat, maize, and rice. In addition, Chinese production of many fruit and vegetable crops has soared. The widespread use of pesticides has had a key role in this vast expansion in food production and without their use…

“China would ‘undergo famine if pesticides were not used’. The warning has come in a recent Ministry of Agriculture document entitled ‘pesticide residues in agricultural products and related safety issues’, reports the national newspaper, the AgriGoods Herald.”

“China has more than 1,700 types of plant disease and insect pests, with major pest outbreaks occurring on over 400 million hectares annually. Laboratory findings released by Chinese agrochemical company Beijing Yoloo Pesticide showed that rice production would be reduced by more than two-thirds if pesticides were not used, and wheat production would be halved.”

Authors: Agrow staff writer
Headline: China warns of famine without pesticides.
Publication: Agrow. 2012. No. 642, June 20.

China Protects Their #1 Ranking in Pears with Fungicides

Records suggest that China has cultivated pears for well over 2500 years. China ranks first in the world in pear production, growing 75% of the world’s output. Annual production has increased twenty-fold in China since the 1950s. A key to production is protecting pears from a disease known as pear scab, which is caused by a fungus that overwinters in leaves on the ground. Spores are released as a result of rain and are carried by air currents to leaves and fruit. Scab lesions form on fruit and, as they enlarge, become large black areas. Fungicides are used in China to prevent pear scab infections.

“Pear scab (Venturia nashicola) is an economically important disease in China. The pathogen is different from the European pear scab fungus (V. pirina) and causes significant annual yield loss on pears, especially on traditional Chinese varieties. … Infection by V. nashicola can occur at any time throughout the growing season from early spring until late autumn, if environmental conditions are conducive. Leaves and fruits become gradually less susceptible to infection as they age. Pear scab in China is managed by routine application of fungicides.”

Authors: Li, B.-H.¹, J.-R. Yang², B-D. Li¹ and X.-M. Xu³
Affiliation: ¹Laiyang Agricultural College, Shangdong Province, China; ² Northwest A & F University, Shaanxi, China; ³ East Malling Research, Kent, UK.
Title: Incidence-density relationship of pear scab (Venturia nashicola) on fruits and leaves.
Publication: Plant Pathology. 2007. 56:120-127.

Chinese Rice Farmers Use Insecticides to Control Invasive US Pest

The rice water weevil is an insect native to the southern US, where its native food was grass. Following the introduction of rice into the US, the weevil shifted from grasses to feed on rice. This shift was first reported in the 1880s. In the late 1950s, the insect was found in northern California rice fields. From there, the weevil was carried across the Pacific into Asia in the mid-1970s. First detected in China in 1988, the rice water weevil has become a major rice pest and has spread all across the country.

“The rice water weevil was recognized as an important invasive pest immediately after its discovery in mainland China because of the severe rice yield losses. The adults feed on the upper leaf surfaces producing longitudinal scars. Larval feeding on roots causes stunted growth, yellowing of the leaves (chlorosis) and plants that are easily uprooted, resulting in few tillers and low grain yield. In mainland China yield losses typically exceeded 10% in the established paddies, but approached over 80% in newly infested areas.”

“Insecticides provide the most effective means of controlling the weevil in China as they do in the United States and Japan.”

Authors: Chen, H.¹, Z. Chen² and Y. Zhou²
Affiliation: ¹ Department of Biology, SUNY-Buffalo; ² Plant Quarantine Institute, Beijing, China
Title: Rice water weevil (Coleoptera: Curculionidae) in mainland China: Invasion, spread and control.
Publication: Crop Protection. 2005. 24:695-702.

China #1 Producer of Garlic Thanks to Fungicides

China is by far the leading producer of garlic in the world, annually growing approximately 10.5 billion kilograms. Chinese garlic accounts for over 77% of world production. Following devastating outbreaks of leaf blight, research was conducted to determine the most effective means of controlling the disease.

“From autumn 2004 to spring 2008, leaf blight was found on garlic leaves in Dangyang County, Hubei, China, with the crop area affected estimated to be over 7000 ha. Garlic yield was reduced by 30% on average, with up to 70% yield losses in some fields during the winter growing season.”

“Epidemiology, cultivar resistance, and chemical controls were investigated during the 2006 to 2008 growing seasons in Dangyang County to improve disease control methods. … Relatively few of the commonly grown cultivars had high levels of resistance to leaf blight. … Fungicide applications in the field were effective in controlling leaf blight… As well, once symptoms are observed, field applications of the fungicides flusilazole (± famoxadone) or mancozeb are recommended to further combat disease.”

Authors: Lu Zheng¹, Rujing LV¹, Junbin Huang¹, Daohong Jiang¹, Xuhong Liu², Tom Hsiang³
Affiliation: ¹ Huazong Agricultural University, Wuhan, Hubei, China; ² Plant Protection Station, Dangyang County, Hubei, China; ³ University of Guelph, Guelph, Ontario, Canada
Title: Integrated control of garlic leaf blight caused by Stemphylium solani in China.
Publication: Canadian Journal of Plant Pathology. 2010. 32(2):135-145.

Organic Methods are Not an Option for Feeding China

China has made remarkable progress in increasing food production to feed its growing population. China can feed itself thanks to the widespread adoption of chemical pesticides and industrial fertilizers. Organic yields are considerably lower without these inputs, which means that widespread adoption of organic practices is not an option for feeding China’s 1.3 billion people.

“Today, China provides enough food for 21% of the world’s population from 9% of the world’s cultivated land. From 1949 to 2000, China’s population increased from 450 million to over 1200 million. During the same period, China’s food crop production increased from 130 Mt to 550 Mt. … This remarkable increase has led China to be able to feed its people.”

“Although organic farming is an old system brought out as a new concept, in our view it is not a practical national farming system for many developing countries – like China. … In organic farming, crop yields and production efficiency are lower and the unit cost of production higher. To produce the same total quantity of any crop, a larger area of land is needed. This additional area is not available in China, so that organic farming on a large scale is not an option to be advocated.”

Authors: Fang Chen & Kaiyuan Wan
Affiliation: Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
Title: The impact of organic agriculture on food quantity, food quality and the environment: a China perspective (Letter to the Editor).
Publication: Soil Use and Management (2005) 21:73-74. Available: http://onlinelibrary.wiley.com/doi/10.1111/j.1475-2743.2005.tb00109.x/abstract