CRANBERRY STOMATAL CONDUCTIVITY

Cranberry (Vaccinium macrocarpon Ericaceae Ait.) stomatal conductivity (SC) was investigated in the field to examine plant response as a fun ction of weather conditions. Measurements were made during fruit matur ation on 14 days between 0540 and 1710 HR, as weather conditions permi tted. SC ranged from 0.02 to 0.08 cm.s-1 and was much lower than for m ost other crops. Scatter plots of SC vs. leaf temperature by day indic ated only a weak linear relationship. When the data were stratified by time of day and by clear and overcast skies, several significant Pear son correlation coefficients suggested a stomatal response. The findin gs, when combined with current knowledge of the physical structure of cranberry stomata, suggest that cranberries behave as xeromorphic plan ts.