Effects Of Genetic Factors And Environmental Conditions On Potato Tuber Yield, Quality And Nutrients Uptake

The field experiments involving3cultivars and7nitrogen rates were conducted inirrigated area at Tumochuan and rainfed area at Wuchuan in the middle of InnerMongolia over two years. The objective of this study is to evaluate the relationshipsbetween potato tuber yield, quality (starch, rough protein and minerals) formation andamount of N, P, K uptake per1000kg tuber and genetic and environmental factors. Theresults are as follows:（1）The average tuber yield was1285.8kg/666.7m2and average starch content (freshbase) was18.6%and average rough protein content (dry base) was9.9%at the fieldexperiments in the middle of Inner Mongolia，and coefficient of variation was45.8%,11.14%and11.31%, respectively.On average, amount of N, P2O5and K2O uptake was4.64kg,2.47kg and6.43kg, and CV was44.4%,37.8%and36.7%, respectively. Theindex variation degree are very big. The analysis result showed that environmentconditions more strongly affected the tuber yield and rough protein content in tuber thangenetic factors, but inversely for the starch content in tuber. For amount of N and Puptake per1000kg tuber yield, environmental conditions was more robust factorscompared to genetic factors, inversely for amount of K uptake per1000kg tuber yield.（2）In the middle of Inner Mongolia, the rank of average content for10mineralnutrients was K (20.95±1.13g/kg), P (4.11±0.37g/kg), S (1.05±0.12g/kg), Mg(1.00±0.05g/kg), Ca (0.19±0.03g/kg), Fe (97.11±7.52mg/kg), Zn (28.37±8.84mg/kg),Mn (27.12±4.29mg/kg), Cu (11.33±1.06mg/kg) and Mo (0.49±0.17mg/kg). The contentof P, S, Mn and Zn in tuber at Tumochuan was significant higher than that at Wuchuan,but inversely for Cu, Ca and Mo. No significant difference occurred for the content of K,Mg and Fe in two areas. Environmental factors had a strong influence on the content of P,K, S, Ca, Mg, Mn, Cu and Zn in tuber whereas genetic factor more greatly affected thecontent of Mo in tuber.（3）Compared with the cultivars Zihuabai and Daxiyang, Longshu3had the longestgrowth period and the highest yield, and the tuber obtained more starch, rough proteinand mineral nutrients like K, Ca, Mg and Fe. This cultivar was sensitive to climate,which result in an unstable yield over years. The growth period for Daxiyang was the shortest, which is suitable to grow in good soil and climate conditions.（4）The average tuber yield and content of starch and rough protein in Tumochuanwas1435kg/666.7m2,18.4%and11.2%, respectively, which was significant higher intuber yield and rough protein content and lower in starch content compared to Wuchuan.Applying manure, manure combined N and P fertilizer and applying N, P and K fertilizertogether significantly increased tuber yield, starch and rough protein content in tuber, tosome degree increased the content of P, K, S, Ca, Mg, Fe and Zn in tuber.（5）With the developing of the growth stage, the variation trend of starch content intuber, rough protein content and the content of mineral nutrient in tuber was different.The content of P, S, Ca, Mn and Zn in tuber at Tumochuan was always higher than that inWuchuan, however, inversely for the content of K, Fe, Cu and Mo. The rank of starchcontent in tuber was Daxiyang> Longshu3> Zihuabai and for rough protein Zihuabai>Longshu3> Daxiyang.（6）The variation trend in the accumulation of stem, leaf, tuber and total plant drymatter and starch, rough protein conformed “S” curve across sites, years, andfertilizations. The accumulation of stem and leaf dry matter conformed cubic equationand others conformed Logistic formula. The accumulated rate of each organ and totalplant dry matter varied in a peak curve, which conformed a quadratic equation for stemand leaf, and V=ae-ct/(1+b e-ct)2formula for other organs. Differences existed in the tuberyield and accumulation of starch and rough protein in tuber and their accumulated rateover sites, cultivars, years and fertilization.（7）The developmental period for Daxiyang and Zihuabai was earlier compared toLongshu3. Thus, tuber yield and amount of accumulation and accumulated rate for thecontent of starch and rough protein in tuber was high in Daxiyang and Zihuabai at theearly tuber formation stage and inversely at the lately tuber formation stage. The peak forthe accumulation of tuber dry matter and content of starch and rough protein in tuberoccurred lately, which greatly limited the production of Longshu3. The yield for tuber,starch content and rough protein content in tuber, and its accumulation rate inTumochuan was higher than those in Wuchuan, and the peak of accumulation rateoccurred earlier compared to Wuchuan. Applying manure, manure combined N and Pfertilizer and applying N, P and K fertilizer together significantly increased accumulationrate of starch and rough protein in tuber in developmental period.（8）Amount of N, P and K uptake per1000kg tuber was6.26kg,3.16kg and9.17kgfor Longshu3,3.98kg,2.24kg and5.16kg for Zihuabai, and3.68kg,2.04kg and4.98 kg for Daxiyang. Amount of N, P and K uptake per1000kg tuber was4.15kg,2.02kgand6.70kg in Wuchuan, and was5.13kg,2.93kg and6.18kg in Tumochuan.