Influence of Main Stem Density on Irish Potato Growth and Yield: A Review

Our review confirms that stem density is affected by seed factors, seedbed conditions and planting methods. Physiologically old seed tubers develop into a ‘weak’ stem density. A loose friable soil that is warm and moist increases sprout emergence leading to a high stem number per hill. This high stem density can be achieved through the use of large seed tubers at planting. The greater the stem densities the higher the yield since more tubers are obtained per plant. An increase in inter stem competition associated with high stem desnity results in a decrease in harvestable tuber weight and size. However, our findings were inconclusive on the influence of varietal differences and planting depth on stem density. The influence of stem density on tuber specific gravity is also yet to be fully understood. We reiterate that producers for ware consumption should aim for low stem populations per hill while conventional seed producer are encouraged to take advantage of higher stem densities.