Exploring the role of soil types on defense and fitness traits of silverleaf nightshade (Solanum elaeagnifolium), a worldwide invasive species through a field survey in the native range

Figures & data

Figure 1. Growth pattern and herbivory in silver-leaf nightshade, Solanum elaeagnifolium. (a) plants before flowering, (b) mature fruits, (c) leaf damage, and (d) flower damage

Figure 2. Map showing the sampling locations for the 50 subpopulations included in this study (black dots), their respective counties and the different soil types in that county. The survey area included 11 Texas counties and covered about 36,000 km²

Table

Predictor	Coefficient	S.E.	Chi-sq	p
1A	Leaf Damage vs Soil type
Intercept (0)	−0.9404	0.1165	65.2	<0.0001
Intercept (1)	0.9364	0.1158	65.33	<0.0001
Intercept (2)	2.1623	0.1565	191	<0.0001
Intercept (3)	3.9676	0.3252	148.87	<0.0001
Clay	−0.3816	0.1263	9.13	0.0025
Sandy	−0.2772	0.1264	4.81	0.0283
Wald chi-sq	16.2			0.0003
Psuedo R2	0.014
AICc	1168.41
BIC	1192.65
1B	Population Scale vs. Soil type
Intercept (0)	0.2414	0.1078	5.01	0.0251
Intercept (1)	2.0135	0.1563	165.81	<.0001
Clay	−0.1621	0.1321	1.51	0.2199
Sandy	0.7219	0.1421	25.8	<.0001
Wald chi-sq	28.7882			<0.001
Psuedo R2	0.0359
AICc	780.98
BIC	797.18
1C	Spines vs. Soil type
Intercept (0)	−1.0877	0.1211	80.74	<.0001
Intercept (1)	1.5449	0.1347	131.52	<.0001
Clay	0.5839	0.1352	18.66	<.0001
Sandy	−0.5154	0.1357	14.42	0.0001
Wald chi-sq	27.2221			<0.001
Psuedo R2	0.0324
AICc	840.765
BIC	858.963

Figure 3. Results from our survey indicate that soil type had a significant effect on Solanum elaeagnifolium height (One-way Anova; F = 7.06; P = .001). Significant differences are based on post hoc Tukey tests represented by lowercase alphabetical letters at P < .05. The X-axis represents soil type and Y- axis plant height (cm)