Vliv vodního deficitu a následné regenerace na vybrané fyziologické charakteristiky u rajčat (Lycopersicum esculentum Mill.)
Authors: H. Hniličková, J. Duffek
Page: 26-31
English / Anglicky:
The effect of water deficit and subsequent regeneration in tomatoes (Lycopersicum esculentum Mitl., the varieties Monika F1, Stupické polní rané and Start F1) as affected the rate ofphotosynthesis (PN), rate of transpiration (E) and stomatal conductance (gs) was studied in pot trials in the years 2000 and 2001. Irrigation was discontinued in a stressed variant (S) for five days, then it was again renewed. Five measurements were done in total (on the2nd and the 5th days of dehydration, and on the 1st,2nd and 4th days of rehydration) using the portable analyser LCA 4. Water deficit resulted in potato plants in reduction of stomatal conductance up to zero value and at the same time the rate of photosynthesis and transpiration decreased. Zero stomatal conductance was reached in the variety Monika F1 on the fifth day of dehydration and in the varieties Stupické and Start F1 on the first day of rehydration. The measured differences in the rate of photosynthesis among control and non-irrigated plants were statistically significant (F = 4.428, p = 0.035193, Table2, Fig. 1). The rate of photosynthesis was measured on the second day of dehydration on average on the level 65.44 % of photosynthesis of control plants. The taken values of the rate of photosynthesis ranged between 5.78 up to 8.20 µmol CO2.m-2.s-1. The drop of dehydration (5th day) resulted in decrease of photosynthesis was on average 20.91 % in the varieties Start F1, Monika F1 and Stupické polní rané, whereas lowest rate of photosynthesis was recorded in the variety Monika F1 (1.21 µmol CO2.m-2.s-1). Gradual regeneration of physiological processes appears during the first four days after rehydration, but pre-stress level was not reached within the trial in any of the studied parameters. Th