The impact of pests and diseases was relatively severe during August 2015 in the main rice regions of China. Maize areas were much less seriously affected.

Rice

For Southern China, south of the Yangtze River and in the middle reaches of the Yangtze River, due to large areas being cultivated either as single cropping rice or double cropping rice, a variety of different phenological stages coexist, which provide favorable conditions for the planthopper. The above average rainfall and normal temperature in easternSouthwest China, south of the Yangtze River, and in the Yangtze River basin has been conducive to both planthopper reproduction and sheath blight dispersal.

The distribution of the rice planthopper during August 2015is shown in figure 4.6(a) and table 4.2. Across China, the total area affectedwith by the insect has reached 20 million ha, with the pest mostly occurringin the northern part of Southern China and the middle andlower reaches of the Yangtze River. The most severely affected areas includeeastern Sichuan, most of Guizhou, central Hubei, most of Hunan, southernJiangsu, central Anhui and northernGuangdong, where in total 10 million ha were damaged.

Rice sheath blight (figure 4.6(b) and table 4.3) has damagedaround 15 million ha across China, with the disease mostly found along themiddle and lower reaches of the Yangtze River and in most areas of SouthernChina and the east of Southwest China. Damage was most severe on 6.7 million hain central Anhui, southern Jiangsu, most of Jiangxi, and in the east of Sichuanprovince.

Figure 4.6. Distribution of therice planthopper (a) and rice sheath blight (b) in China, August 2015

Table 4.2. Areas in China affectedby rice planthopper, August 2015

Table 4.3. Areas in China affectedby rice sheath blight, August 2015

Maize

In general, during August 2015, the situation of maizediseases and pests in the main maize producing regions of China was relativelyuneventful. In August, northern leaf blight only occurred in Northeast andSouthwest China. Meanwhile, the temperature and precipitationin Northeast, Huanghuaihai and Inner Mongolia provided a proper environment forarmyworm reproduction.

As shown in figure 4.7(a), only some parts of Heilongjiang,Jilin, Liaoning, Yunnan, Sichuan, and Guizhou provinces were affected bynorthern leaf blight. Within the diseased regions, the total damaged area isaround 560 thousand ha.

For armyworms, the total area affected in China is around1.5 million ha, with the pest mostly observed in Northeast, Inner Mongolia, andHuanghuaihai (figure 4.7(b) and table 4.4). Especially severe attacks arereported from eastern Inner Mongolia, southern Heilongjiang, Jilin, Liaoning,northern Hebei, Beijing, Tianjin, and some parts in Henan and Shandong, totaling1.3 million ha.

Figure 4.7. Distribution of maizenorthern leaf blight (a) and armyworm (b) in China, August 2015

Table 4.4. Occurrence of armywormin China, August 2015