Predicting the emergence of potato sprouts

Abstract

SUMMARYSprout emergence in the potato variety Estima was investigated in controlled environment and field experiments. The effects of temperature, physiological age, planting date and soil moisture were examined in controlled environments and the results were compared with the emergence of physiologically young and old seed in field experiments with different soil types, planting dates and planting depths.Elongation of sprouts could be described by a lag period of slow growth followed by a period of rapid linear growth. The lag period was shorter with increase in temperature up to 20 °C and sprout length at planting up to c. 10 mm. The lag period was slightly reduced by warming seed at 10 °C before planting, compared with planting seed directly from cold storage. The rate of linear growth increased with temperature up to 20 °C but was similar for young and old seed at different planting dates. The rate of growth was lower in dry soil than in soil near to field capacity, particularly at high temperatures.The observed date of emergence in the field was usually later than predicted, particularly with shallow planting, but prediction was improved by accounting for soil moisture. The use of this model should give more accurate estimation of emergence for farm operations and crop growth models than existing equations.