Articles
THE PHOTOSYNTHETIC ACTIVITY OF DIFFERENT PEACH GENOTYPES
Three genotypes selected at the I.S.F. of Rome, were used for this purpose: standard vegetative behaviour (STD), semidwarf (SDW), dwarf (DW).
174 plants for each genotype were used, grafted on GF677, randomized in blocks of 8. The field was equipped with an automatic system for the environment control.
The photosynthetic activity was studied by analyzing single leaves with a Li-Coor 6002 device.
The following experiments were carried out:
- Analysis of the photosynthetic activity related to PAR variations, shading with nets to reduce light of 20, 50, 80%. All measures were taken from 7:30 to 8:30 a.m.
- Analysis of the photosyntetic activity during the day, taking records at 8:00 a.m., 11:00 a.m., and 5:00 p.m.
- Variation of the photosynthetic activity, during the season, taking records from the end of April through beginning of July.
Leaf area, stomata number, chlorophyll content were also recorded.
A good correlation was established between the photosynthetic activity and PAR with the following c.c.
| STD = 0.91, SDW = 0.90, DW = 0.91 |
On the whole, the photosynthetic activity, whose reduction is related to light decrease, is higher both in SDW compared to ST and in DW compared to SDW trees.