Development Of Drought Tolerant Potato Variety And High-yield Cultivation Techniques For Spring Planting Potato In Guizhou

The seasonal drought and high temperature are two extreme weather conditions thatseriously impact the potato production in southwest cool mountain areas of China. Thepurpose of this study is to explore the effect of soil ecological response on yield of thepotato new varieties and the mechanism of yield improvement. The experiments wereconducted in Weining, Guizhou during2008～2009, to analyze the effects of tillagetechniques on soil ecological response and the mechanism of yield improvement of thepotato new varieties. The summarized as following:Under the green manure and plastic mulching condition, the yield of Qianyu1canreach2976.4kg/mu, which is the highest yield among others, while the distance of row is90cm and the planting density is4148plant/mu. Therefore, Qianyu1was used forfollowing high yield cultivation studies.The tillage techniques significantly impact the daily average temperature of topsoilduring growth stage of potato (planting to middle of may), while the positive effects oftillage technique gradually reduced during later growth stage. The average topsoiltemperature treated with green manure+plastic mulching mode (GMPM) and simplyplastic mulching model (PM) could increase3.6℃and2.9℃per day, the accumulatedtemperature could increase184.1℃and149.3℃respectively. Obviously, the plastic filmcontributes largely to the soil temperature increase. The overall temperature increasingperformance of tillage techniques is as following: green manure+plastic mulching mode(GMPM) is the best, followed by simply plastic mulching model (PM) and green manure(GM), the conventional tillage technique is the worst.The water content of topsoil (0～21cm) also impacted by tillage techniques. Untilmiddle of May, GMPM, GM and PM can help to increase soil water content by12.93%,6.3%and10.88%respectively. While after middle of May, the water content of the topsoiltreated with GMPM and PM dropped6.35%and6.4%respectively. During the wholegrowth stage (Late Mar through late Aug), the variation of water content of top soil treatedwith GMPM and PM showed significantly when compare with control (p<0.05).According to the impact power of tillage techniques on dry matter accumulation, therank of techniques could be: GMPM>GM>CK>PM. The dry matter accumulation fromGM significantly increased (17.8%higher than control) during the whole growth stage;that from GMPM increased25.6%(P<0.01), and the commodization rate of tuber is 82.6%(P<0.01); the water utilization efficiency (WUE) of soil treated with CK, GM,GMPM and PM are69.38,65.84,47.92and33.75kg/hm2·mm. the water stress responsewas analyzed with FLINT1model, the results suggested that the water stress waspresented from all tillage techniques except GM during middle of May, and the severestress was predicted for PM treatment.