Thorough coverage of tobacco plants is critical for effective blue mold control. Application parameters will vary depending on growth stage. The information presented in this section is based on research conducted by Agriculture and Agri-food Canada on the application of Aliette WDG at different stages of tobacco growth.

Tobacco growth stages can be identified by plant height. The taller the plant, the more product needed to cover the foliage. The table below outlines how finished spray volume of Aliette can be varied to optimize coverage as tobacco plants grow.  Note that it is important to stay within the total rates specified for tobacco on the product label (2.5-3.25 kg product/ha). 

Table 1 - Application of Aliette WDG on tobacco.

Be sure to stay within the total rates on the label. This table indicates spray mix rates onlyA. 

Growth Stage Plant Height Banded Spray Mix Rate
Early plant growth up to 25 cm 100 L/ha
Early–mid plant growth 25–36 cm 170 L/ha
Mid-late plant growth 36–70 cm 320 L/ha
Late plant growth 70 cm to topping stage 500-560 L/ha
AThe labelled broadcast application rate for Aliette WDG is 2.5–3.25 kg of product/ha in 450–560 L water/ha — a ratio of 1 kg of product for every 175 L of water (1 kg:175 L). A single application should never exceed 3.25 kg of product in 560 L water/ha. Never exceed 3–4 applications per year and never exceed 10 kg product/ha/yr.

Hollow cone nozzles configured as in the figures below will provide sufficient coverage at the volumes shown in Table 1. Thorough coverage of tobacco plants can be obtained with these sprayer configurations when using a hydraulic-type sprayer such as a Hi-Boy.

Diagram showing 2 young tobacco plants with a spray boom above containing 3 nozzles over each plant. One nozzle is positioned directly above the plant, and 2 are angled about 45 degrees on either side of the plant

Figure 1 - Sprayer nozzle configuration for freshly transplanted tobacco (0-3 weeks after planting). Use a spray boom arrangement with a single nozzle centered over the tobacco row for early applications. (Figure courtesy of BASF Canada Inc.)

Diagram showing 2 mid-sized tobacco plants with a spray boom above containing 5 nozzles per plant. One nozzle is positioned directly above the plant, two are angled at about 45 degrees on either side of the top sides he plant angled about 45 degrees with one positioned towards the top of the plant, and the other just below the middle of the plant.

Figure 2. Sprayer nozzle configuration for mid-sized tobacco (knee-high plants). Use additional nozzles mounted on drop pipes, centred between the rows on either side of the centre nozzle, and aimed at plants on either side of the drop pipes. (Figure courtesy of BASF Canada Inc.)

Diagram showing 2 large tobacco plants with a spray boom surrounding it containing 7 nozzles per plant. One nozzle is positioned directly above the plant, and 3 are positioned on each side of the plant, in the upper, middle and lower third of the plant.

Figure 3 - Nozzle configuration for large-sized tobacco (waist-high or taller plants). Mount the drop nozzles on a swivel to allow small adjustments in mounting angle to get the best coverage at various growth stages. v