[Triennal research into the effects induced by growth regulators on Ligustrum shrubs]

English. In 1977, 1978 and 1978 some trials were made on Ligustrum sinensis and L. ovalifolium to assure the retardant effect induced by Atrinal (Dikegulac Sodium 20% a.p.). All the tests of 1977 were carried out to find the optimal dosage for Ligustrum sinensis. The phytotoxic symptoms were restricted and never compromised the appearance of the hedge. Shoot growth was considerably reduced in comparison with the control by both concentrations (1.25 and 0.625% of Atrinal). Growth inhibition stopped at the end of June in the case of the higher concentration and at the beginning of the same month in the case of the concentration. The test of the following year with ACR 1093 (Dikegulac-Sodium 90%) gave no results. The concentration (0.25) was too high and caused very strong phytotoxic symptoms; moreover there was no emission of lateral shoots. In the same year the different parts of Ligustrum sinensis hedge were treated by 0.25 MH, respectively 1, 2 and 3 times. The best results were obtained in the hedge parts sprayed twice, where MH reduced the shoot growth of 40%. In 1979 Ligustrum ovalifolium was treated with Atrinal 0.25%. This regulator reduced the shoot growth of 30% in comparison with the control and induced many lateral shoots.

Italian. Nel 1977, 1978, 1979 sono state condotte ricerche al fine di accertare, su differenti specie di ligustro, gli effetti provocati da Dikegulac Sodium. Nel 1978 tali effetti sono stati anche comparati con quelli provocati da MH. Al termine del triennio di ricerche e stato messo a punto il dosaggio ottimale al fine di ottenere una riduzione di sviluppo delle piante.