Dynamics of the number of cranberry tipworm (Dasineura vaccinii S.) in America large-fruited cranberry plantation in the vegetation season in Latvia | Dzērveņu dzinumu pangodiņa (Dasineura vaccinii S.) skaita dinamika Amerikas lielogu dzērveņu stādījumā veģetācijas sezonā Latvijā
2010
Apenite, I., Latvian Plant Protection Research Centre, Riga (Latvia)
The cranbery tipworm Dasineura vaccinii S. (Diptera, Cecidomyiidae) dynamics of American large-fruited cranberry (Oxycoccus macrocarpus or Vaccinium macrocarpon (Ait.) Pers.) was studied in the north-east part of Latvia in 2005 and 2006. Main attention was paid to the effect of weather conditions (air temperature, precipitation) on the course of D. vaccinii development stages (eggs, 1st-3rd larval stages, and pupae). Dynamics of D. vaccinii flying out and further development was dependent on the plants growth stage which, in its turn, was affected by the air temperature and relative humidity in the cranberry plantation. The maximum infestation level by D. vaccinii was observed during the 1st and 2nd 10-day period of July when more than half (50-66.9%) of all cranberry vertical apical shoots were invaded. In the large-fruited cranberry plantation, two D. vaccinii generations were observed: the first generation developed in the 2nd and 3rd 10-day period of June, the second generation - in the 3rd 10-day period of July and the 1st 10-day period of August. Egg hatching of the first generation was delayed by the low minimal air temperature (below 0 deg C) at the beginning of the vegetation season, but later egg hatching was influenced by the amount and intensity of precipitation, which was not statistically provable. The development course of D. vaccinii 2nd-3rd-stage larvae and the intensity of pupation were affected by the maximal air temperature and precipitation during the vegetation season.
اظهر المزيد [+] اقل [-]