BEIJING, April 30 (Reuters) – A pest that ravages corn crops is spreading in southern China, posing a growing threat to the world’s No. 2 producer of the grain, said an expert based in the country.
Native to the Americas, the fall armyworm has spread east in recent years, causing as much as $3 billion worth of damage in Africa, before reaching parts of Asia last year.
Before turning into a moth, the worm feasts in large numbers on the leaves and stems of many plant species and can infest and damage hundreds of hectares of corn overnight, according to the Food and Agriculture Organization of the United Nations.
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After reaching China’s southwestern Yunnan province in January, it was detected in the neighbouring Guangxi region and Guangdong province this month, said Wang Zhenying, a researcher at the Institute of Plant Protection at the Chinese Academy of Agricultural Sciences, a government think-tank.
So far, it has damaged about 8,493 hectares planted with corn, he said.
“I expect that it will cover the Yangtze River basin by May and June, and it is likely to reach North China and Northeast China in June and July,” Wang told Reuters on Tuesday.
China grows corn on about 42 million hectares and is expected to produce about 257 million tonnes this year.
Warmer, southern provinces plant corn over the winter, but China’s most important production areas are in the north, especially the northeastern provinces of Jilin, Liaoning and Heilongjiang.
So far, the insect has moved very fast, spreading to new provinces as corn seedlings emerged in the spring, said Wang.
The moth can fly long distances, allowing it to reach new regions rapidly, and it has been known to reduce corn output by about 20 percent in some areas.
However, Wang said damage could be restricted to around 5 percent with effective monitoring and control.
China’s Ministry of Agriculture and Rural Affairs has set up monitoring points in border provinces, while local agriculture departments are working with farmers to select pesticides to tackle the threat, according to a recent state media report.
“In Yunnan, the damage has been very light,” said Wang, thanks to the early detection of the pest.
The fall armyworm could also impact sugarcane, millet and sorghum crops, he added.