Improving Yield and Profitability of Processing Tomatoes in Northwest China with Potassium

The Xinjiang region of northwest China is the largest producer of processing tomatoes in the country. In fact, it’s one of the largest processing tomato growing regions of the world. About seven million tonnes of tomato fruit is produced annually, China is also the world’s top exporter of tomato paste. Tomatoes require a relatively large amount of potassium (K) for adequate growth, but falling soil K fertility in the region is leading to a reduction in tomato yield and quality.

To combat this problem, IPNI joined forces with the Xinjiang Academy of Agricultural Sciences, and the tomato industry to study the right K fertilizer sources, application rates and timings, and to assess the potential risks for any chloride imbalances that may occur if Potassium chloride (KCl) use was to increase in Xinjiang. The research showed that the use of KCl resulted in similar tomato yield and quality (and profit) as fertilization with potassium sulfate (K2SO4) or potassium nitrate (KNO3) applied at the same K rate. Applying K at a rate of 120 kg K2O/ha produced the highest tomato yield and economic return. Split application of KCl provided greater fruit yield and profit, compared to a one-time application. It is now recommended that farmers first apply 70% of their K requirement as KCl in the fall.

The new recommendation, now regarded as the appropriate management practice for K fertilization of processing tomatoes in Xinjiang, limits any undesirable chloride accumulation in the soil, supporting the production of high quality tomato paste in the processing plant. These results now provide the core technical message for training materials produced in Xinjiang as local farmers look to boost profit along with their improving yield.

Credit: IPNI

Read more about the project here.