ChileanJAR

The above ground biomass and root dry matter accumulation ofwheat (Triticum aestivum L.) grown in Southern Chile, the absorption ofN, P, K, Ca, Mg, Zn, Mn, Cu and B during development and the extraction ofthese nutrients per kilogram ofgrain are described. The biomass dry matter accumulation curves were similar for the winter and spring crops, although the spring growing period was shorter. The root dry matter accumulation curves were similar to the above ground biomass curves, but the proportion of root biomass decreased between the CD 23 (26%) and anthesis (7%) stages. Nutrient absorption rates were generally correlated to dry matter production up to anthesis, with K, Cu and B being the exceptions. In general, the nutrient extraction per kilogram of grain was in agreement with the values reported elsewhere. Differences in extraction for sorne nutrients were found between cultivars. Different sowing dates and growing seasons produced significant differences in the extraction of sorne nutrients per kilogram of grain.