| dc.description.abstract | A study was conducted during the dry periods of 1990 in the
field and in the greenhouse at the University of Nairobi's Faculty of
Agriculture Farm, Kabete to investigate varietal differences in
photosynthesis, growth and yield responses of beans (Phaseolus
vulgaris L.) under different watering regimes. Four indigenous bean
varieties ('Ulonzo', "Pinto', 'Zebra beans', 'White Haricot') from
marginal rainfall areas, four ('Rosecoco (Merul', 'Pocho', 'Local',
Okuodo) from high rainfall areas were used along with the two
improved varieties ('GLP-1004' and 'GLP-2') which have been
developed for marginal and high rainfall areas respectively. Watering
treatments were imposed from seed emergence to late podding stages '
using a line-source sprinkler irrigation system in Experiment I and
differential irrigation frequency in Experiment II. Photosynthesis and
leaf area (LA)were measured using infra-red gas analyser and a Li-COR
automatic LAintegrator respectively.
Results showed that Ulonzo consistently had higher net
photosynthetic rates than the other varieties under both watering
levels. It was also observed that varieties from marginal rainfall areas,
in general had higher photosynthetic values than those from high
rainfall areas. Ulonzo also out yielded all the other varieties and as with
photosynthesis, it was also noticed that varieties collected from
marginal areas generally gave higher yields than those from high
rainfall areas.
This study indicates that there are varietal differences in
photosynthesis, growth and yield responses of beans and that varieties
from marginal rainfall areas tend to perform better than those from
high rainfall areas. | en |
