Articles
CONTROL OF PLANT GROWTH BY COVERING MATERIALS FOR GREENHOUSES WHICH ALTER THE SPECTRAL DISTRIBUTION OF TRANSMITTED LIGHT
Effects on the growth, development and yield of cucumbers (Cucumis sativus L. cv.
Hokushin) and tomatoes (Lycopersicon esculentum Mill. cv.
Saturn) were examined under materials which selectively intercepted FR or R.
In the FR-intercepted greenhouse (R/FR=2.33), for both cucumber and tomato, the plant vegetative growth was significantly inhibited with shorter stem length and internodes; the fruit harvesting dates were delayed and the yield of the fruit in the initial stages was reduced when compared with the control (R/FR=1.11). In the R-intercepted greenhouse (R/FR=0.58), the flowering date was significantly earlier only for tomato.
However plant vegetative growth was significantly promoted with longer stem length and internodes.
For both species the fruit harvesting dates occurred earlier and the yield of fruit in the initial stage was greater when compared with the control.
Effects were more obvious in cucumber than in tomato.
The experimental results showed that these covering materials are effective in controlling vegetative growth, reproductive growth and improving the morphological characteristics of the plant canopy or community.