GROWTH AND DEVELOPMENT OF SOME FIELD CROPS AS INFLUENCED BY CLIMATIC PHENOMENA AT TWO DIVERSE LATITUDES

Abstract

The investigation involved establishment of an experimental site at Madison, Wisconsin, latitude 43 °N., and another at Beaverlodge, Alberta, 55 °N., where 10 annual crops representing varieties of wheat, oats, barley peas and millet were grown for two years. Growth and phenology of the varieties were correlated with meteorological conditions at the two points. Climatic phenomena studied were insolation, air temperature, photo- and thermoperiod, and water relations. Over the growing season, insolation was approximately equal at Madison and Beaverlodge, despite the high latitude of the latter point. On the other hand, the effective heat supply at Beaverlodge was only 60 per cent of that at Madison. The photoperiods at the two locations were found to be quite different.Under the long summer days of the more northerly latitude at Beaverlodge all crops except millet developed as well as at Madison. Millet proliferated vegetatively and did not head at Beaverlodge. The yield of seed of all crops except millet was associated with much less vegetation at the northern station. The earlier-maturing varieties did comparatively better under cool temperatures than did the later-maturing types. The results indicate that from the standpoint of seed production the plants at Beaverlodge were subjected to cooler temperatures than the comparable plants at Madison. In the phase from heading to maturity this temperature difference was less pronounced than from emergence to heading. All varieties grew taller and greater in size at Madison, but all except millet produced heavier kernels at Beaver-lodge.