The efficacy of different seed priming osmotica on the establishment of maize (Zea mays L.) caryopses

The purpose of this Communication is to compare the efficacy of different seed priming osmotica on the germination and emergence of maize caryopses. First, a laboratory experiment was carried out to determine the effects of different seed priming osmotica on germination. The osmotica used are 0.1% copper sulphate, 0.1% zinc sulphate and 0.1% sodium sulphate. A control of unprimed caryopses was used for comparative analysis. In general, seed priming significantly increased the final caryopses germination. Caryopses primed in copper sulphate, however, gave the highest final germination. Then, field trials to determine the final seedling emergence of caryopsis in the field were carried out in a semi-arid area in southern Zimbabwe. Results testify that priming in copper sulphate and zinc sulphate significantly increased seed emergence by 43% and 29%, respectively, while priming in sodium sulphate did not significantly increase emergence. The study thus recommends copper sulphate as the most suitable seed priming osmotica.