Evaluation on the situation of fertilization on potato in Shaanxi province

In order to understand the current situation of fertilizer application and nutrients resource input problems of farmers on potato in Shaanxi province and to put forward countermeasures to solve the problems, the household survey data of the project of soil testing and formulated fertilization from 2006 to 2009 were analyzed and evaluated. There were totally 14 counties and 1890 households for the survey. The results show that in Loess plateau area of northern Shaanxi and Qin-ba mountain area of southern Shaanxi, the yields of potato are 23.0 t/ha and 15.4 t/ha, and the average yield of the whole province is 22.3 t/ha. The ratios of households of using organic manure are 99.0% and 60.6% respectively, and the average of the whole province is 95.4%. The rates of chemical fertilizer N, P2O5 and K2O are 155, 78 and 13 kg/ha respectively in the whole province, which shows diminishing returns trends. Compared with the rational fertilizer rates, in Loess plateau area of northern Shaanxi and Qin-ba mountain area of southern Shaanxi, for chemical N application, 43.0% and 4.0% are rational respectively, the average of the whole province is 39.4%; 24.5% and 50.3% are excessive respectively, the average of the whole province is 26.9%. For chemical P2O5 application, 64.6% and 16.0% are rational respectively, the average of the whole province is 60.1%; 21.9% and 56.0% are excessive respectively, the average of the whole province is 25.0%. For chemical K2O application, 96.9% and 93.1% are insufficient respectively, the average of the whole province is 96.6%. The current situation of household fertilization on potato in Shaanxi province is that the nitrogen and phosphate fertilizer inputs are both excessive and insufficient, and the potassium fertilizer and organic manure inputs are both insufficient. Therefore, the reasonable application of nitrogen and phosphate fertilizer, increasing potassium fertilizer and organic manure inputs and increasing top dressing fertilizers, especially in Qin-Ba mountain area of southern Shaanxi are all should be concerned for households in Shaanxi province.