Association of apple powdery mildew (Podosphaera leucotricha) and anthracnose (Neofabraea malicorticis) epidemics with environmental factors and agronomic practices in Chencha highlands, southern Ethiopia

Table 2 Analysis of the logistic regression model for apples for powdery mildew and anthracnose severity and likelihood ratio tests on independent variables in Chencha district of the Gamo zone, southern Ethiopia, during the 2021 and 2022 production years

Independent variable	df	Severity of apple powdery mildew, LRT				Severity of anthracnose, LRT
		Type 1 analysis (VEF)		Type 3 analysis (VEL)		Type 1 analysis (VEF)		Type 3 analysis (VEL)
		DR	Pr > χ²	DR	Pr > χ²	DR	Pr > χ²	DR	Pr > χ²
Altitude	1	0.37	0.5440	17.14	< 0.0001	6.08	0.0137	11.57	0.0007
Years	1	62.05	< 0.0001	0.89	0.3462	35.80	< 0.0001	6.60	0.0102
Survey site	1	0.01	0.9171	0.35	0.5552	45.91	< 0.0001	45.33	< 0.0001
Age of apple tree	3	62.18	< 0.0001	23.05	< 0.0001	111.90	< 0.0001	9.61	0.0059
Source of planting materials	1	5.36	0.0206	0.78	0.3756	0.05	0.8172	1.02	0.3136
Cropping system	4	148.07	< .0001	50.34	< 0.0001	19.68	0.0006	8.06	0.0346
Growth stage	2	62.76	< .0001	2.87	0.2380	6.61	0.0367	0.74	0.6915
Apple tree management	1	1.93	0.1648	9.42	0.0021	0.99	0.3190	1.42	0.2340
Precipitation	1	46.71	< 0.0001	11.82	0.0006	32.11	< 0.0001	3.07	0.0799
Relative humidity	1	0.00	0.9845	2.11	0.1459	15.26	< 0.0001	6.92	0.0085
Temperature	1	6.45	0.0111	0.06	0.8023	0.09	0.7594	0.12	0.7279
Disease status	2	261.30	< 0.0001	77.45	< 0.0001	2261.79	< 0.0001	743.74	< 0.0001
Disease management	2	266.88	< 0.0001	7.25	0.0266	14.78	0.0006	6.40	0.0496
Weed management	2	36.42	< 0.0001	21.51	< 0.0001	32.81	< 0.0001	33.46	< 0.0001
Yield (t/ha)	3	386.32	< 0.0001	386.32	< 0.0001	83.50	< 0.0001	83.50	< 0.0001

LRT Likelihood ratio test, VEF Variable entered first in the model, VEL Variable entered last in the model, DR Deviance reduction, Pr Probability of an x² value exceeding the deviance reduction, x² = Chi square, df Degrees of freedom