Evaluation of acibenzolar-S-methyl and other low-toxicity products for control of rose powdery mildew (Podosphaera pannosa) in greenhouses

Figures & data

Table I. Effect of different products against rose powdery mildew (Podosphaera pannosa) on cv Pink Monte Roso.

		Application date (31 January, before inoculation^a)		Disease severity^b (%)
Treatment	Product	Concentration/ml^c	Application way^d (10 ml)	13 February	20 February
1	Control (water)		Watering	23.3a	60.4a
2	Control (water)		Spray	25.8a	60.4a
3	Bion 50 WG	0.1 mg	Watering	6.7de	15.8d
4	Bion 50 WG	0.1 mg	Spray	0.8f	17.1d
5	Bion 50 WG	0.01 mg	Watering	22.9ab	45.4bc
6	Bion 50 WG	0.01 mg	Spray	17.1abcd	46.7bc
7	Resistim	0.1 ml	Watering	10.0bcde	42.9c
8	Resistim	0.1 ml	Spray	4.2def^e	42.1c
9	Resistim	0.05 ml	Watering	8.3de	55.4ab
10	Potassium phosphate	5 mg	Watering	22.1abc	45.0c
11	Potassium phosphate	5 mg	Spray	12.9bcde	52.1abc
12	Potassium phosphate	10 mg	Watering	20.8abcd	55.0ab
^aInoculation date: 5 February.
^bMean values with the same letters within a column are not significantly different (P<0.05).
^cConcentration of commercial products. Dilutions were made with distilled water.
^dTreatments were applied by drenching the pots or by foliar spray with 10 ml of solution per pot.
^eThe leaves were heavily damaged after the treatment. New growth of susceptible young leaves had merely started.

Table II. Effect of different products against rose powdery mildew (P. pannosa) on cv Pink Monte Rosa.

		First application (25 March, before inoculation^a)		Second application (7 April, after inoculation^a)		Disease severity^b (%)
Treatment	Product	Concentration/ml^c	Application way^d	Concentration/ml^c	Application way^d	7 April	14 April
1	Control (water)		Watering, 10 ml			15.0	36.2a
2	Control (water + Tween 20)	10^−4 ml (0.01%) Tween	Spray, 100 ml			13.8a	39.6a
3	Control (water )		Spray, 100 ml		Spray, 100 ml	6.3abc	31.2ab
4	Control (water + Tween 20)		Watering, 100 ml	10^−4 ml	Spray, 100 ml	7.9abc	38.3ab
5	Bion 50 WG	0.1 mg	Watering, 10 ml			1.7d	7.1d
6	Bion 50 WG	0.1 mg	Spray, 10 ml			3.7c	17.5c
7	Bion 50 WG	0.05 mg	Watering, 10 ml			7.5abc	22.5bc
8	Bion 50 WG	0.05 mg	Spray, 10 ml			4.1bc	25.8abc
9	Resistim	0.1 ml	Watering, 10 ml			6.3abc	23.7bc
10	Resistim	0.1 ml	Watering, 10 ml	0.1 ml	Watering, 10 ml	8.3ab	28.3abc
11	Resistim + Tween 20	0.01 ml + 10^−4 ml	Spray, 100 ml			5.8bc	21.7bc
12	Resistim + Tween 20	0.01 ml + 10^−4 ml	Watering, 10 ml	0.01 ml + 10^−4 ml	Spray, 100 ml	7.9abc	20.0
^aInoculation date: 30 March.
^bMean values with the same letters within a column are not significantly different (P<0.05).
^cConcentration of commercial products. Dilutions were made with distilled water.
^dTreatments were applied by drenching the pots or by foliar spray. The total amount of solution applied was 10 or 100 ml/pot.

Table III. Effect of different products against rose powdery mildew (P. pannosa) on cv Pink Monte Rosa.

		First application (18 February, before inoculation^a)		Second application (2 March, after inoculation^a)		Disease severity^b (%)
Treatment	Product	Concentration/ml^c	Application way^d	Concentration/ml^c	Application way^d	2 March	9 March
1	Control (water)		Watering, 10 ml			40.8a	74.2abc
2	Control (water)		Spray, 50 ml		Spray, 50 ml	45.8a	75.4ab
3	Bion 50 WG	0.2 mg	Watering, 10 ml			6.3c	30.0e
4	Bion 50 WG	0.1 mg	Watering, 10 ml			19.4b	52.5d
5	BABA	0.4 mg	Watering, 10 ml			37.1a	75.8ab
6	BABA	0.2 mg	Watering, 10 ml			35.8a	75.9a
7	C-Pro	2 mg	Watering, 10 ml			34.6a	74.2abc
8	NeemAzal	5 µl	Watering, 10 ml			37.9a	79.2a
9	NeemAzal	5 µl	Watering, 10 ml	1 µl	Spray, 50 ml	40.7a	75.0ab
10	NeemAzal	1 µl	Watering, 10 ml	1 µl	Spray, 50 ml	43.0a	68.8bc
11	Dewacid	50 µl	Spray, 50 ml			40.0a	77.1a
12	Dewacid	25 µl	Watering, 10 ml			45.4a	77.9a
13	Dewacid	25 µl	Watering, 10 ml	25 µl	Watering, 10 ml	42.5a	80.8a
14	Dewasid	5 µl	Spray, 50 ml	5 µl	Spray, 50 ml	37.1a	75.4ab
15	Bion 50 WG+Dewacid	0.05 mg+25 µl	Watering, 10 ml			23.8b	66.7c
^aInoculation date: 23 February.
^bMean values with the same letters within a column are not significantly different (P<0.05).
^cConcentration of commercial products. Dilutions were made with distilled water.
^dTreatments were applied by drenching the pots or by foliar spray. The total amount of solution applied was 10 or 50 ml/pot.