DETERMINATION OF CLIMATICALLY SUITABLE AREAS FOR SOYBEAN (Glycine max (L.) MERR.) PRODUCTION IN MANITOBA

Abstract

The effects of daily maximum and minimum temperature and photoperiod on the phenological development of soybean cultivars Maple Presto and McCall were studied under field conditions over the period 1979–1982. Experimental sites were located throughout the agricultural area of Manitoba. Data collected were used to derive a biometeorological time scale for each cultivar. For this purpose, the growth of the crop was divided into four stages: planting to emergence, emergence to flowering, flowering to beginning pod fill, and beginning pod fill to maturity. When the biometeorological time scale developed from the first 3 yr of the study was used to predict the duration of each stage of development during the fourth year, the largest root mean square error of estimation was 4.0 days. A biometeorological time scale developed from all 4 yr of data was applied to historical weather station data in order to determine the probability of maturing soybeans in Manitoba. According to the analyses, only a small area in central Manitoba south of 50° N latitude is capable of maturing the cultivar McCall 90% of the time. Most of the agricultural region can expect to mature the cultivar Maple Presto 90% of the time.Key words: Soybeans, climatically suitable areas