Alexandru Todea

ASPECTS CONCERNING TO CHEMOTHERAPY OF FIGHTING AGAINST MEALY ATTACK FROM DURMAST NATURAL REGENERATION

Among the biotical natural causes which conduce on the amplify of the durmast drying phenomenon is considered first the durmast mealy attack with a large spreading produced by the pathogen Microsphaera abbreviata. The fungus, attack first leaves of saplings, or sprouts and continuous to the leaves and stems of mature trees. The most harmful attack effect are recorded in degraded rammels, in culture, nurseries and especially in young natural regenerations which are presented like foliage mass on large surfaces. Considering the importance of this to formation in new rammels where placed experiments in Sylvicultural Departments ray of: Dej, Gherla and Cluj, where was remark the effect of some fungicide (Systhane, Karathane, Trifmine and Alert) compared with the Bumper 250 EC standard produce. The results where synthesize in table 1. Table 1 The efficiency of SYSTHANE preventing the attack of Microsphaera abbreviata (f.c.Oidium alphitoides) Cvercinee regeneration Nr Infested leaves crt Product Sylvicultural department Conc. (%) Applied dose F(%) I GA Z E(%) Cluj 0,04 0,400 10,0 1,4 0,14 4,4 95,6 Turda 0,04 0,400 8,8 2,7 0,24 6,3 93,7 1 SYSTHANE Gherla 0,04 0,400 9,3 1,9 0,18 4,7 95,3 Cluj 0,03 0,300 11,6 1,9 0,22 6,9 53,1 Turda 0,03 0,300 11,2 2,1 0,24 5,9 94,1 2 BUMPER 250EC Gherla 0,03 0,300 11,0 2,0 0,22 5,5 94,5 Cluj - - 71,4 4,5 3,21 - - Turda - - 76,9 5,0 3,84 - - 3 Martor Gherla - - 80,5 5,0 4,03 - - According to obtained results and of ascertains we may conclude: - the chemotherapy represent an efficient solution fighting against the mealy attack; - to chose the right combination of substances must to be made according to their efficiency, value and the provision possibilities.