Major progress made in project to control soybean yield reduction from continuous and alternating cropping

The reporter learned from relevant departments that the project "Research and Demonstration of Key Technologies for Controlling Soybean Yield Reduction under Continuous and Alternating Cropping," tendered by the Municipal Science and Technology Bureau, has achieved major progress after two years of scientific research.

The project was carried out in Yilan and Bayan counties, the two counties with the largest soybean area in Harbin. Through key technology research, soybean varieties resistant to continuous and alternating cropping were selected, including Kenfeng 16, Heinong 48, Kangxian 4, and Hefeng 47. A formula fertilization technique was proposed with 45 kg of nitrogen, 60-67.5 kg of phosphorus, 67.5-75 kg of potassium, and 7.5 kg of the trace element boron per hectare, along with foliar fertilizer spraying at the flowering stage, autumn deep loosening and soil preparation technology, and biological control technologies for root diseases and pests using Trichoderma agents and biocontrol granules, among other key technologies for controlling soybean yield reduction under continuous and alternating cropping.

In 2006, demonstration applications in the two counties increased continuous-cropping soybean yields by 9.81% and alternating-cropping yields by 11.4%. Under unfavorable natural conditions, continuous and alternating cropping soybean yields reached 2348.5 kg per hectare, exceeding the province's 2006 average soybean yield of 691 kg.

In 2007, Harbin suffered its most severe drought in 50 years, and this technology still achieved remarkable results. Bayan County reached a yield of 2145 kg per hectare, an increase of 13.2%. The average yield in the plains area of Yilan County was 2136 kg per hectare, an increase of 8.8% by comparison.

Over two years, the cumulative area of continuous and alternating cropping soybeans using this scientific research achievement reached 21,000 hectares, increasing soybean production by 4.77 million kg and boosting farmers' economic benefits by more than 18 million yuan.

Liu Zhongtang, a renowned soybean expert at the Provincial Academy of Agricultural Sciences, believes that the "key technologies for controlling soybean yield reduction under continuous and alternating cropping" are genuinely effective, that controlling such yield reduction is entirely possible, and that relatively high yields can be created, which is of great significance and offers better prospects for increasing Harbin's soybean production.

It is understood that Harbin is a major soybean production area in the country, with more than 60% of its soybean sown area under continuous and alternating cropping. In response to problems in Harbin's soybean production such as the large area of continuous and alternating cropping, severe occurrence of diseases and pests, and low yields, the Municipal Science and Technology Bureau designed the project "Research and Demonstration of Key Technologies for Controlling Soybean Yield Reduction under Continuous and Alternating Cropping" in early 2006. The Heilongjiang Academy of Agricultural Sciences, the Northeast Institute of Geography and Agroecology of the Chinese Academy of Sciences, and the Harbin Agricultural Technology Extension Service Center jointly won the bid and undertook the project.