Some effects of irrigation and plant density on the water relations of high density coffee (Coffea arabica L.) in Kenya
Measurements were made of xylem water potentials, stomatal apertures, shoot growth, yield and yield components in two-to four year-old trees of Coffea arabica growing at a range of high planting densities, and in one experiment given irrigation for different periods during the year. Irrigation greatly increased lateral extension growth and node production but, as node numbers were negatively correlated with fruits per node, fruit yield was relatively little affected. In trees irrigated only once during a very dry period, lateral growth rate, node production and stomatal apertures were generally higher at around 8000 plants ha-1 than at 5000 and at even higher densities either remained constant or declined. Midday xylem water potentials were lowest, not at the times of greatest soil water deficit, but a few days after irrigation or rain showers. The relationship of water potential to plant density was variable but on days when potentials were below - 16.5 bar, the highest potentials were found in the middle range of densities. Thus within the range of practicable high densities, increasing density appears not to increase plant water stress and may even alleviate it. Among the irrigation treatments, the one in which water was given frequently at all times of the year did not support the highest yield and it is suggested that a period of soil water deficit to stimulate blossoming or limit vegetative growth might be of advantage
Main Authors: | , |
---|---|
Format: | biblioteca |
Published: |
1979
|
Subjects: | COFFEA ARABICA, RIEGO, NECESIDADES DE AGUA, ESPACIAMIENTO, POBLACION, FISIOLOGIA, ETAPAS DE DESARROLLO DE LA PLANTA, CRECIMIENTO DE RAMAS, CRECIMIENTO DE LA PLANTA, |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|