| Abstract: | Xinjiang is known as the oasis irrigation agricultural area, characterized by plenty of sunshine favorable for cotton growth. However, the oases, dotted in the gobi deserts, are distributed at the foot of the enclosed mountains and a steppe in the centre of the Turpan Basin, and thus has a rathe vulnerable eco-environment. Since the 1980s, the cotton-growing industry has developed very quickly. The area of cotton-growing belt has increased from 181,000 hectares in 1980 to 866,600 hectares in 1997, which accounted for 34.7% of the total cultivated area in Xinjiang. The cotton output has correspondingly increased from 79,200 tons to 1.05 million tons and per hectare output has also increased from 438 kg to 1211 kg1]. In recent decades, changes have taken place in agricultural products, such as the ratio of cotton and grain, total output and per hectare output with the expansion of cotton-growing belt. Before 1982, per hectare cotton output remained below 450 kg. Since 1982, thanks to the adoption of plastic film technique and such a planation mode as "short, dense and early", namely, to select short-stalked, close planting and early maturing varieties, the per hectare cotton output has undergone a steady increase. After 1984, per hectare output reached more than 900 kg, and since 1995 it has reached 1435 kg per hectare, 9 folds more than that in the 1950s1,2]. However the harmful organisms have accompanied the repaid expansion of the cotton-growing belt and the degree of deterioration has also kept increasing. Harmful organisms present a bottleneck for the further development of cotton production. To effectively control and protect against harmful organisms is the key to guaranteeing the steady development of Xinjiang cotton industry. |
