The effect of plant extracts as seed treatments to control bacterial leaf spot of tomato in Tanzania

Table 3 The effect of treatment with selected plant extracts from Aloe vera, Coffea arabica, Glycyrrhiza uralensis and Yucca schidigera on tomato seed germination, seedling vigor and dry weight of tomato plants

Treatment	Seed germination^a			Vigor index (%)^b	Dry mass (g)
Treatment	NS (%)	ABS (%)	DS (%)	Vigor index (%)^b	Dry mass (g)
Control
Sterile distilled water	90.50b	3.00a	6.50a	702.51b	0.16a
Copper sulphate	92.80ab	2.30a	5.00ab	707.60b	0.14a
Untreated seed	92.00ab	3.50a	4.50ab	718.06b	0.16a
Plant extract
A. vera	94.80a	1.80a	3.50ab	749.39ab	0.14a
C. arabica	95.50a	2.50a	2.00b	784.77a	0.14a
G. uralensis	92.80ab	2.80a	4.50ab	714.33b	0.16a
Y. schidigera	94.30a	2.00a	3.80ab	741.91ab	0.14a
Mean	93.20	2.50	4.30	731.22	0.14
F test	**	ns	**	**	ns

ns not significant
** Significant at P = 0.05
^aSeed germination states: NS normal seedlings, ABS abnormal seedlings, DS dead seed. Each value is the percentage from 400 seeds test
^bSeedling vigor index (Vi) was calculated as Vi = (mean root length + mean shoot length) × (percentage germination) (Abdul-Baki and Anderson 1973); means followed by the same letters in a column are not significantly different based on the SNK test at P = 0.05