The effect of poor quality seed and various levels of grading factors on the germination, emergence and yield of wheat

Abstract

High quality seed is essential for establishing productive stands of wheat. Seed should have, amongst others, a high germination percentage, be free of seed borne diseases and should not contain any weed seed. Protein content (PC), hectolitre mass (HLM) and falling nudmber (FN) are three important quality characteristics determining the grading of wheat at delivery point. Seed with high and low values of these three quality requirements were planted over a two year period under dryland and irrigation conditions to determine the effect of these quality parameters on the yield of the following crop. Seed with various levels of preharvest sprouting damage were also planted to determine the effect of sprouting on the field performance of the crop. Results from this study showed that germination was not affected by grading factors, but the emergence of seed with low HLM was significantly reduced compared to high HLM seed. Low PC had a significant effect on the crop, especially under dryland conditions, while FN did not have an effect. Severely sprouted seed had a significant negative effect on the emergence and yield, especially when seeds were carried over to the next planting season. However, a low intensity of sprouting did not affect the yield negatively. End results indicated that using low quality seed for planting can have a negative effect on crop yield. It is concluded that producers should use certified seed that is true to variety, is clean and has a high germination percentage for crop production.