R459 Improving Cultivation Practices in Potatoes
Aim: To improve cultivation practices in potatoes to increase soil structural stability, lengthen the window of cultivatability, improve soil N use efficiency, reduce wastage and energy consumption and produce consistently larger marketable yields, thereby improving competitiveness and sustainability.
Potato seedbeds need to be fine, friable, non-compacted, free-draining and structurally stable. Many growers fail to achieve all of these attributes owing to poor attention to soil status at cultivation, time pressure and use of high-powered tractors capable of either working soil unfit for cultivation whilst wet or pulverising the soil excessively when dry. Around 70% of the potato area in England is grown on soils with high risk of structural degradation and, owing to the wide-scale adoption of de-stoning machinery, degradation has increased. Over a longer time period, organic matter content has also decreased, which has increased the risk of structural damage with intensive cultivation.
Whilst soil type can vary considerably across fields, even in uniform-textured fields there remains large variability in natural water content and bulk density at planting which will affect the seedbed produced if cultivation takes place at a fixed depth. Reducing the depth of cultivation slightly can often reduce compaction. The soil nitrogen supply (SNS) is likely to be modified greatly by timing and depth of cultivations, soil water content and rooting activity. Since the current N fertilizer recommendation system frequently underestimates the SNS index resulting in over-application of N fertilizer, improvements to cultivations should increase N utilization and make recommendations more reliable.