THE USE OF MORPHOREGULANTS INSTEAD OF THE SUMMER CUT IN APRICOT TREES
In 2-year-old apricot crowns, and still more in those of the third growth season when quite a large size has already been attained, application of the summer-cut technique becomes a time-consuming matter. It was therefore our aim to replace this technique by a more expedient one; preference being given to the spray of growth retardants. The actual reason for their application was to induce retardation in the growth of the new shoot which, after a certain period of stagnation, would resume its growth, while the buds set prior to application of the retarding agents during the first swing of development would produce premature growth.
Workers of the Institute of Fruit Culture, Brno University of Agriculture, branch of the Faculty of Agronomy at Lednice na Morave, have subjected to testing the effects of morphoregulants as exerted on growth and fertility of apricot, peach, and apple trees. In apricot trees the spray of maleic-acid hydrazide has proved highly effective, while that of chlorcholine chloride (CCC) showed but lesser effects.
The spray of either 2 g maleic-acid hydrazide solution or 2 ml CCC per 1 litre water was first applied early in April, prior to apricot blooming, and the treatment was repeated seven times, or nine times if necessary, at one week's intervals except for the time of blooming.