Reducao de nitrato em plantas jovens de café cultivadas em diferentes níveis de luz e de nitrogenio
The effect of levels of light and nitrogen on the activity of the enzyme nitrate reductase and its relationship with the availability of sugars and nitrate was studied in leaves of coffee plants (Coffea arabica L. cv. Catuaí). Ten month old plants were grown on pots containing a mixture of soil and compost, and were kept at full or 50 percent sunlight. Half of the plants of each light treatment received nitrogen supply. The results showed that the activity of nitrate reductase was higher on plants supplied with nitrogen at both light treatments. For the same nitrogen level, plants grown under full sunlight presented lower nitrate reductase activity, higher nitrate and sugars concentrations, and higher transpiration rates than plants kept at 50 percent sunlight. These results indicate that the lower nitrate reductase activity of plants grown under full sunlight was apparently not due to limitations of available nitrate and sugars to supply the energy necessary for nitrate reduction
| Main Authors: | , , , |
|---|---|
| Format: | biblioteca |
| Published: |
1990
|
| Subjects: | COFFEA ARABICA, NITRATO REDUCTASA, AZUCARES, NITRATOS, ACTIVIDAD ENZIMATICA, CULTIVO BAJO SOL, |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|