1. Rice pests and diseases

The impact of pests and diseases was moderate during mid-September 2018 in the main rice regions of China. The temperature was lower than during the previous year in central and north-east China; precipitation was higher in central China, and south China. North China, east China, and southwest China were affected by typhoons and the resulting abundant rain provided suitable conditions for the migration of rice planthopper (Nilaparvata lugens) and rice leaf roller (Cnaphalocrocis medinalis) and the dispersal of rice sheath blight (Rhizoctonia solani).

Rice planthopper

The distribution of rice planthopper during mid September 2018 is shown in Figure 1.1 and Table 1.1. The total area affected reached 5.7 million hectares, with the pest severely occurring in north-eastern Sichuan, and western Heilongjiang, moderately in central Hunan, northern Jiangxi, central Jiangsu, and eastern Anhui and only slightly in central Yunnan, central Guangxi, and central Hubei.

Figure 1.1 Distribution of rice planthopper in China (mid September 2018)

Table 1.1 Statistics of rice planthopper inChina (mid September 2018)

Rice leaf roller

Rice leaf roller (Figure 1.2 and Table1.2) damaged around 5.0 million hectares, with severe infestations  in north-eastern Sichuan, southern Jiangsu, and central Hunan, moderate infestation in eastern Anhui, central Guangxi, and central Jiangxi. Only slight impacts affected eastern Yunnan, and western Heilongjiang.

Figure 1.2 Distribution of rice leaf roller in China (mid September 2018)

Table 1.2 Statistics of rice leaf roller in China (mid September 2018)

Rice sheath blight

Rice sheath blight (Figure 1.3 and Table1.3) damaged around 7.3 million hectares, mostly in eastern Sichuan, western Heilongjiang, central Hunan, and eastern Anhui (severe impact), but to a lesser extent in central Guangxi, central Jiangxi, and central Jiangsu where moderate impact occurred. Central Hubei, central Jilin and eastern Yunnan had light infestations.

Figure 1.3 Distribution of rice sheathblight in China (mid September 2018)

Table 1.3 Statistics of rice sheath blight inChina (mid September 2018)

2. Maize pests and diseases

Maize suffered moderately from pest and disease attacks during mid September in the main production areas. Low temperature and high humidity in southern and northern China were suitable to armyworm (Mythimna separata) reproduction and northern leaf blight (Setosphaeria turcica) dispersal.

Maize armyworm

The distribution of maize army worm in mid September 2018 is shown in Figure1.4 and Table 1.4. The total area affected  reached 3.9 million hectares, with the pest severely affecting central Jilin, southern Heilongjiang, northern Henan and southern Hebei. North-western Shandong, central Shaanxi, and southern Liaoning where moderately affected while southern Shanxi, northern Hunan and central Xinjiang suffered only lightly.

Figure1.4 Distribution of maize armyworm in China (mid September 2018)

Table1.4 Statistics of maize armyworm in China (mid September 2018)

Maize northern leaf blight

Maize northern leaf blight (Figure 1.5 and Table 1.5) damaged around 2.3 million hectares, with the disease severely occurring in central Jilin, southern Heilongjiang and western Shandong; moderately in northern Liaoning, southern Hebei and only slightly in central Inner Mongolia, northern Henan, and southern Shanxi.

Figure1.5 Distribution of maize northern leaf blight in China (mid September 2018)

Table1.5 Statistics of maize northern leaf blight in China (mid September 2018)