The objective of this research was to study the aerial dispersion of Lasiodiplodia theobromae, the causal agent of coconut (Cocos nucifera) leaf blight, and its relationship with pluviometric precipitation. Five wind catcher spore traps and one Burkard spore trap were installed in a coconut plantation, at a height of 1.80 m from the ground. The conidia were captured in transparent tapes covered with gelvatol and vaseline. Every week, the tapes were retrieved and mounted on slides for microscopy, where the number of trapped conidia was determinated. For the wind catcher trap, the highest amount of trapped conidia was 231 units in the month of October. For the Burkard spore trap the highest amount of captured conidia was 3072 units achieved in June. In general, during a-year-round sampling, there was a predominance of conidia liberation during the diurnal period. The highest amount of conidia was captured from 6:00 to 10:00 a.m. The number of conidia trapped by the two types of devices correlated positively with the amount of precipitation ranging from 25 to 80 mm. Above 80 mm of rain, the correlation was negative. Curves of tendency were established indicating that the amount of conidia captured by the two types of spore traps is a function of monthly precipitation and that both devices showed similar curves of tendency. The liberation of conidia was stimulated whenever precipitation reached a minimum of 25 mm. The curves maximum point, correspond to 80 mm of rain, indicating that above this volume the conidia were precipitated.
leaf blight; aerobiology; epidemiology
