Occurrence of Fruit Doubles in the 2004 Season Associated with Heat and Drought Stress in Previous Year

摘要

A higher than normal incidence of fruit doubles occurred in the Czech Republic in the 2004 season. Fruit dou-' bles or twinning was most frequently observed among plum fruits sold in town markets, in mirabelle in small gardens in Prague and environs,and in apple, variety James Grieve, on the experimental plots of the Research Institute of Crop Production, Prague -Ruzyně. In other cases, only the terminal fruits were fully developed, usually in one apple spur, while basal fruits were retarded. Basedon meteorological data and literature reports, it can be concluded that the higher incidence of fruit doubles in the CR in 2004 is correlated with heat and drought stress in 2003, The period between August 3 and August 15, 2003, was the time during which differentiating and developing flower buds might have been stressed and injured. In this period, there were high temperatures (30 to 38.9°C) each day and trees suffered water stress.