Ecological Archives E085-063-A6

Anurag A. Agrawal. 2004. Resistance and susceptibility of milkweed to herbivore attack: consequences of competition, root herbivory, and plant genetic variation. Ecology 85:2118–2133.

Appendix F. Multivariate analyses followed by mixed-model univariate analyses for effects of grass competition, root herbivory by beetles, and full sibling family of milkweed on the natural log of number of stems, sum of stem heights, and sum of stem widths in the spring of the second growing season. The likelihood-ratio test was used for the random effect (Family). Denominator degrees of freedom for the univariate fixed effects range from 119 to 124 and were determined by the Satterthwaite approximation.

 
MANOVA
Stems
Height
Widths
 

Wilks' lambda

df

F

P

F

P

F

P

F

P

Grass

0.795

3, 115

9.89

<0.001

 

11.14

0.001

 

3.34

0.070

 

13.43

<0.001

Beetle

0.803

3, 115

9.42

<0.001

 

0.00

0.978

 

12.48

0.001

 

11.60

0.001

Grass × Beetle

0.948

3, 115

2.12

0.102

 

4.88

0.029

 

5.92

0.016

 

5.94

0.016

Family

0.582

39, 341

1.76

0.005

0.9

 

0.171

3.8

 

0.026

3.5

 

0.031


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