| Minqin belongs to typical temperate continental desert climate. The average annual rainfall is 110 mm, and the annual evaporation can reach 2644 mm. Most of rainfall below 5 mm is invalid and has little significance in agricultural production. Drought and water shortage is a major factor of Minqin desertification, and is the main reason of limiting the Minqin for the sustained development of agriculture, and water-saving irrigation technology is one of the main measures in the future sustainable development of agriculture. In this study, we investigated the drip of water-saving irrigation of the Jiu Mian 8 to identify the standard model parameters of suitable drip irrigation, cultivation patterns and cropping patterns in Minqin. To achieve effective water-saving agriculture and protect the ecological environment, we provided a theoretical reference for the species and water-saving drip irrigation under plastic film technology in Minqin. The results were as follows:(1) When the Jiu Mian 8 was in the whole growth period of the drips, the soil VWC in every drip treatment area showed a downward trend overall, moreover, VWC in 0cm～60cm and 80cm～100cm two soil layer respectively decreased 11.2% and 2.7% on the seedling and squaring stage, decreased 5.4% and 3.4% on the flowering stage, decreased 13.7% and 5% on the boll stage, and decreased 3.1% and 2.5% on the boll opening stage. Decrease of 0cm～60cm soil layer VWC compared to 80cm～100cm was significant. It was showed that the change of soil VWC 0cm～60cm had an important impact on cotton growth.(2) Considering the influence of drip irrigation on some factors such as cotton plant height, yield and other production, we established standard model parameters of cotton drip irrigation under plastic film in Minqin through the an alysis of the VWC change of different soil layer, different determination times and the time interval under different drip irrigation. Meanwhile, according to different planting patterns, two sets of standard model parameters were formed. The first scheme can guarantee irrigation water before sowing ,drip irrigation eight times about 240m3/666.67m2 in whole growth period(except non-effective rainfall). Sowing and seedling emergence is not irrigation, one time in squaring stage,one time in flowering stage,five times in flower bell stage , one time in boll opening stage. The first drip irrigation is on squaring stage in the June 20, the last time on August 30.The second scheme not can guarantee irrigation water before sowing , drip irrigation ten times about 290m~3/666.67m~2 in whole growth period(except non-effective rainfall).one time after sowing, After emergence and seedling,squaring stage is not drip irrigation, one time in early bud stage,five times in flower bell stage , one time in boll opening stage. After cotton planting, the first drip irrigation was done in order to meet the demand on the water at seed germination, the last is still on August 30.(3) Jiu Mian 8 should be sowed in mid-April, seeding rate was controled in 6～7 kg/666.67m2.During the early squaring, early bell flowers and topping period, 1～2g,3～4g,5g,98% (the mepiquat content) DPC powder was respectively used to chemical control. When the cotton aphid was occurred seriously in middle to late july,10 grams of 50% hypertonic pirimicarb (WP) was used to prevent by both positive and negative local leaf spraying . Under the first standard model parameters of cotton drip irrigation under plastic film,the first drip irrigation (before and after the flowering period) should be controlled in 30m~3/666.67m~2,the evaporation was large in July～August,due to increased irrigation,respectively,110m~3/666.67m~2,80m~3/666.67m~2 , the last drip irrigation was still on early September about 30m~3/666.67m~2. Follow the above cultivation model, 240m~3/666.67m~2 drip irrigation and 20,000/666.67m~2 plant density of cultivation mode in the whole growth period, the yield reached the top about 328.4kg/666.67m2.. Compared with flood irrigation that was commonly used in the management of local, saving-water 46.7% and the yield increased about 33.8%.
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