Evaluation of plant extracts for tomato late blight control in Cameroon

Figures & data

Table 1  Effect of plant extracts at 3% on four distinct stages of Phytophthora infestans pathogenesis: percent sporangial germination inhibition after 24 h of incubation on 1.5% water agar medium at 18°C in darkness, lesion size of late blight on 7–8-week-old detached tomato leaflets in Petri dishes, incubation period and percent severity of late blight on tomato plants incubated in the greenhouse for 7 days at 21°C during the day and 18°C during the night, with 12 h photoperiod

Treatment	Sporangia inhibition (%)	Lesion size (cm^2)	Incubation period (days)	Disease severity (%)
Tephrosia vogelii	67.95±1.76 c^*	2.18±0.46 fg	4 a	8.09±0.71 e
Entandrophragma angolense	53.21±2.06 b	3.68±0.36 e	3 b	8.10±0.73 e
Eucalyptus saligna	31.45±1.10 e	9.80±0.80 d	3 b	20.98±1.98 d
Clausena anisata	20.63±1.25 f	3.00±0.23 ef	5 a	4.73±0.91 f
Garcinia smeathmannii	12.83±0.53 g	19.80±0.17 c	2 c	48.05±1.55 b
Ageratum houstonianum	14.88±1.06 g	0.18±0.17 hi	3 b	4.20±0.41 f
Deinbollia saligna	6.50±1.29 h	20.50±0.58 b	1 d	28.75±0.96 c
Metalaxyl	72.45±2.80 a	0.40±0.49 hi	–^†	0.00±0.00 g
Maneb	70.33±2.05 bc	1.33±0.98 gh	5 a	3.20±0.36 f
Uninoculated control		0.00±0.00 i	–^†	0.00±0.00 g
Distilled water-sprayed		23.08±1.43 a	1 cd	55.50±1.73 a
^*Means (±SEM) in a column with the same letter are not significantly (P < 0.05) different according to Tukey's HSD multiple comparison test. Values are means of four experiments with four replicates per experiment
^†No late blight lesion developed during the 7-day observation period