Impact of non-optimal temperature and bioregulator on root and seedling vigour of corn [Articol]

Abstract

Take into account that the corn vigour has the strong correlated field emergence and yield, the purpose of this work was to evaluate the combined influence of non-optimal temperatures and a natural bioregulator on the vigour of corn root and seedling. The seeds of Porumbeni 455 corn hybrid pre-treated with natural bioregulator (JS) extracted from Juniperus sabina were subjected to treatment at 50°C (heat test) and at 10°C (cold test). The vigour of root and seedling was assessed after seed germination. Temperature above the optimum significantly affected both the vigour of root and the vigour of seedling, but temperature below the optimum only reduced the root vigour of the tested corn hybrid. The JS bioregulator contributed to an increase in root system vigour. Corn seeds pre-treated with JS had root vigour greater than untreated ones by 13.08 and 18.46%, respectively in the cold and heat test. The evaluation of factor impact showed that the temperature influenced both the root and seedling vigour more than the treatment with the bioregulator, and their combined effect significantly modified only the root vigour.