Proposal for the prediction of spring infection by Blumeriella jaapii "Rehm" v. Arx.
1992
Veghelyi, K. (Gyumolcs- es Disznovenytermesztesi Kut.-Fejl. Vall., (Hungary))
The date of spring infection with Blumeriella haapii, causing leaf spots and early leaf abscission in sour cherry orchards, depended on the overwintering conditions of leaves infected in the previous year and on the number of frost days. Studies and observations made between 1969 and 1978, and a consideration of the climatic data, showed a correlation between the number of frost-free days and the development of the conidial form of the pathogen. The quantity of precipitation in the winter half-year did not influence the development of the fungus. If the development of the pathogen is regularly checked, the appearance of conidial infection in spring can be expected after 60-65 frost-free days, calculated from 1 January. The data of a 10-year period indicate that there may be a deviation of 3-4 weeks from one year to the next in the date when this period occurs. Foliage disinfection in autumn prior to leaf abscission, with preparations containing 0.1 o/o benonyl (Chinoin, Fundazol), or after leaf abscission with 1.5-2.0 o/o DNOC (Novenda), sprayed in large quantities, will hinder the overwintering of the fungus.
Показать больше [+] Меньше [-]