dc.description.abstract | Climbing snap beans have the potential of increasing productivity and competitiveness in
domestic and export markets, but suitable varieties
with market demanded p
od quality
characteristics and
preferred agronomic traits are not available to smallholder farmers in Kenya
and other countries in east, central and west Africa. The objective of the study was to select
climbing snap beans with market
preferred pod quality characteristics, pod yield and disease
resistance from locally developed breeding populations and advanced lines. Twenty F
5.7
lines
with type IV growth habit were evaluated at Mwea and Embu during the 2013 long rain and
short rain sea
sons
. Diseases were scored on 1 to 9 disease scale, where scores of 1
-
3 were
considered resistant; 4 to 6, intermediate; and 7 to 9, as susceptible. After pod formation, plots
were harvested every other day. Pods were graded as extra
-
fine, fine and bobby
using standard
commercial criteria. Results showed that there were significant genotypic differences for plant
vigour, disease resistance, days to first picking, pod yield, pod length and market grades among
the new lines. Plant vigor scores varied from 1
to 7 at Embu, and 1.7 to 3.5 Mwea. Check
varieties were the most vigorous lines in both sites but they were not the highest yielders.
Anthracnose and angular were the most severe diseases especially at Embu where sprinkler
irrigation was used. Except for K
SV27
-
69
-
4
-
1
-
2T, all other lines showed resistant reactions to
anthracnose and angular leaf spot. Rust incidence was low throughout the season and all
genotypes showed resistant reactions. Duration to 50% flowering varied from 43.5 to 52 days in
Embu, and 3
1.8 to 48.5 days in Mwea. This may have contributed to differences in days to first
picking which varied from 56 to 60 days after planting. Pod yield over 9 harvests in Embu varied
from 3,252 to 10,626 kg ha
-
1
. The total yield from 18 harvests in Mwea vari
ed from 16,214 to
23,724 kg ha
-
1
. New lines out
-
yielded the the checks by 56.6%. The new lines produced an
average of 44.1% premium grades. However, this varied with genotypes and was not
significantly influenced by number of harvests. The results of this
study indicate that new
climbing snap bean varieties with market demanded pod characteristics, high yield potential and
resistance to major diseases can be developed from the selected lines. Exploitation of the longer
harvest period of climbing beans can c
ontribute to higher yields and better returns to investment
especially for smallholder farmers, and to the overall competitiveness of the snap bean sub-sector | en_US |