Ha. Vandeventer et al., A STUDY OF SINGLE AND MULTIPLE STRESS SEED VIGOR TESTS FOR UNDETERIORATED SEED LOTS OF WHEAT, Seed science and technology, 21(1), 1993, pp. 117-125
Moisture and temperature stresses occurring in the seedbed of dryland
wheat in the summer rainfall area of South Africa result in reduced em
ergence, even of undeteriorated seed lots. The purpose of this study w
as to determine the usefulness of a number of single and multiple stre
ss laboratory tests in predicting relative emergence of 18 undeteriora
ted seed lots of wheat (six wheat cultivars, each represented by three
seed lots from different production localities) at two field trial si
tes. There was a lack of significant correlations at one site, but a c
onsiderable number at the other. Single stress tests (germination at 9
-degrees-C and thermotolerance induction response) were better predict
ors of relative emergence than multiple stress tests (accelerated agei
ng and the complex stressing vigour test). Promising results were also
obtained with the standard germination test, which included a determi
nation of speed of germination.