Breeding for resistance to bean common mosaic virus, halo bllght, pseudomonas phaseolicola and anthracnose, colletotrichum lidemutttlenum in common bean (phaseolus vulgaris L.)
Abstract
Five popular bean cultivars susceptible to bean common mosaic virus, halo blight
Pseudomonas phaseolicola and anthracnose Colletotrichum lindemuthianum were
crossed in a dial lei with two other cultivars resistant to these pathogens. Progenies were
evaluated at the National Horticultural Research Centre - Thika and the University of
Nairobi - Kabete. Lines combining resistance to two or more of the diseases were
selected. Mode of inheritance of resistance to BCMV in cultivar L226-10 (52) and that
of resistance to Pseudomonas phaseolicola and Col/etotrichum lindemunthianum in
NB-123 were studied.
Out of 1800 pollinations of the diallel crossing to seven bean cultivars, 1400 were
successful, giving an overall 78.3% of successful crosses with each pod containing 3-7
seeds. L226-10 (52) was rated resistant to BCMV isolate 510 both in the green house
and in the field. The F1' F2 and F3 progenies of the crosses GLP-2 x GLP-24, GLP-2 x
M535, GLP-288 x GLP-24, GLP-24 x GLP-2, GLP-24 x M535, GLP-x.92 x M535, M535
x GLP-2, M535 x GLP-2, M535 x GLP-288, M535 x GLP-24 and M535 x GLP-x.92 were
highly tolerant to the virus isolate both in the green house and in the field. NB-123 was
rated resistant to Pseudomonas phaseolicola both in the green house and in the field.
The F1' F2 and F3progenies with NB-123 and M535 as one of the parents were resistant
to the pathogen both in the green house and in the field. NB-123 was rated resistant to
Coletotrichum lindemuthianum both in the green house
and in the field. The Fl' F2 and F3 progenies with M535 and NB-123 as one of the
parents had a high degree of resistance to the pathogen both in the green house and
in the field.
Segregation of the F2 progenies for resistance to BCMV of the crosses GLP-2 x
L226-10 (52), GLP-x.92 x L226-10 (52) and their reciprocals did not differ from the
expected ratio 3:1 (resistantsusceptible). Segregation of the F3 progenies for resistance
to BCMV of the same crosses and their reciprocals also did not differ from the expected
ratio 2:1 (segregating:non-segregating). It was therefore concluded that resistance to
BCMV in L226-10 (52) is governed by a single dominant gene.
TAe segregation of the F2 progenies for resistance to Pseudomonas phaseolicoJa
of the crosses GLP-2 x NB-123, GLP- x.92 x NB-123 and their reciprocals differed from
the expected ratio 3:1 (resistantsusceptible). Segregation of the F3 progenies for
resistant to Pseudomonas phaseoJicoJa of the same crosses and their reciprocals differed
from the expected ratio 2:1 (segregating:non-segregating).lt was therefore concluded
that resistance to Pseudomonas phaseolicoJa in NB-123 is not governed by a single
dominant gene.
The segregation of the F2 proqenies for resistance to CoJ/etotrichum
Jindemuthianum of the crosses GLP-2 x NB-123, GLP-x.92 x NB-123 and their reciprocals
did not differ from the expected ratio 3:1 (resistant:susceptible). Segregation of the F3
progenies for resistance to CoJ/etotrichum Jindemuthianum for the
same
Citation
Master of science in plant breedingPublisher
University of Nairobi Department of Crop Science