Efficacy and Cost Benefits of Grafting in the Management of Bacterial Wilt (Ralstonia solanacearum) of Tomato
Abstract
Bacterial wilt (Ralstonia solanacearum) is the second most important constraint to
tomato production after Fusarium wilt in Kenya. This study was conducted to assess the
efficacy of two tomato rootstocks, Kilele and Roma in the management of bacterial wilt of
tomato. The experiment was conducted in a greenhouse that is naturally infested with bacterial
wilt pathogen at the University of Embu. Three treatments were used, Kilele grafted to Roma,
Roma grafted to Kilele and non-grafted Kilele. The experiment was laid out in a randomised
complete block design with three replications. Plants were monitored for bacterial wilt
symptoms immediately after transplanting. Disease related data such as days to the onset of
wilting (DTOW), days to complete wilting (DTCW), disease incidences, disease severity and
weights of different fruit qualities were recorded during the study period. Data on incidences
and severity score, DTOW, DTCW, the weights of different fruit qualities per plant, graft take
rate and graft survival percentage were coded and entered in MS Excel spreadsheet. Analysis
of Variance (ANOVA) was performed on disease incidences, DTOW, DTCW, browning and
oozing scores and yield whereas graft take and graft survival percentage were subjected to Ttest
using
SAS
software.
Means
were
compared
using
the
least
significance
difference
(LSD)
at
5%
significance
level.
Bacterial
wilt
disease
severity
and
incidence
was
reduced
by
20%
when
wilt
susceptible
Roma
cultivar
was
grafted
onto
Kilele
rootstock.
The
study
indicated
that
bacterial
wilt
can
be
managed
to an extent by grafting susceptible varieties on tolerant
rootstocks such as Kilele.