The effect of climatic factors on production of spring wheat quantity to quality ratio in southern Finland

Abstract

Interrelationships between climatic factors and spring wheat yield and quality were examined with 21 years field experiments. The formation of gluten was less at dry conditions (total precipitation under 50 mm) and total precipitation exceeded 130—140 mm. The optimum daily temperature for gluten production was some 15—17°C during grain filling. The gluten content decreased if daily minimum and maximum temperatures exceeded 11—12°C and 21—22°C, respectively. The effect of temperature and rainfall were not, however, significant in early maturing varieties. The climatic factors and grain yield did not correlate. Grain yield and protein yield had strong positive relationship, which was perhaps a consequence of supply and utilization of nitrogen. It is concluded that climatic factors affecting yield to quality ration in wheat may be excessive rains before heading and high temperature during grain filling. Interaction between weather and nitrogen are discussed to optimize correct timing of nitrogen fertilization for amount and quality of economic wheat yield.