Megaenvironmental Trials

Soybean (Glycinemax) has become one of the major crops produced worldwide owing to its versatile good properties. Although the interest in growing soybeans in Europe increased, little is known about growing areas and no norms for classification soybean varieties and Maturity Group (MG) exists. This requires the study to estimate different growing areas by identifying Mega Environments in Europe and to identify standard varieties which represent most stable each MG .

The sample was provided from 10 countries by the participants of the trial and then was chosen to represent the maturity groups which are grown in Europe. Every participant was requested to start with a weekly survey of the growth stage beginning with calendar week (CW) 23 until at least CW 40. The phenological growth stages were evaluated either with the German BBCH Scale (Munger et al., 1997) or with the American Code from Fehr and Caviness (1977).

The results show that each MG tends to mature earlier when moving to the south. Different components of genotype, location and genotype-location effects were all significant for flowering and maturity. The growth development of the stable varieties at the different locations indicates that early MGs are less photoperiod sensitive compared to the later-maturing genotypes which differ stronger in the calendar week and cumulative temperature. The growth development of the genotypes indicates that maturity is generally depending more strongly on temperature.

A map of growing areas in Europe can be established with identified MEs. The standard varieties can also be used as benchmark varieties to compare or classify for example new breeding material and as checks in field trials in general. More information on the European breeding material considering maturity could be obtained by examining the known loci on maturity and further developing markers which are functional in European breeding material. The identified MEs provide for the first time information about growing areas of different MGs in Europe.