Your Guide to Applying Foliar Fungicides

Getting the best result from a foliar fungicide requires you choose the right product and apply it at the right time and at the right rate. This post outlines some of the key considerations when applying a foliar fungicide.

Factors to consider before applying foliar fungicide

Factors to consider before applying foliar fungicides include:

• the disease pressure – dependent on variety, weather events and inoculum source

• whether there are visual symptoms present – monitor the crop for infection levels

• whether you are applying the fungicide as a seed treatment, in-furrow or foliar

• the growth stage of your crop – apply fungicides to protect plant parts that contribute most to yield

• the crop yield potential – in low disease + low yielding crops, fewer sprays are needed. In moderate to heavy disease + higher yielding crops, multiple fungicide inputs are often required.

What is the objective of applying a foliar fungicide?

The main goal of a foliar fungicide application is to increase profitability.

Fungicides do not generally increase yield, but they protect the yield potential of a given crop by maintaining the green vegetative area (including leaves, stems and seed pods).

Foliar diseases reduce the green area of the plant and its ability to produce energy (via photosynthesis), particularly during key growth stages such as pod fill.

Getting the best result

There are a number of key considerations when applying fungicides to achieve the best result. These factors include:

• Timing of application
• Product selection
• Rate selection.

Timing of application

Timing of application of foliar fungicides is the most important consideration for effective disease control.

Key points to consider with fungicide timing are:

• Application at critical growth stages - protect plant tissues that contribute to yield
• Multiple applications may be required as fungicides cannot protect leaves that haven’t emerged at the time of spraying
• High disease pressure/susceptible variety = earlier spraying + multiple sprays
• Applying fungicides to prevent the disease from becoming established. Do not rely on curative ability.

Product selection

The choice of fungicide to apply will depend on:

• The disease/s present
• Severity of disease pressure
• Crop growth stage
• Yield potential
• Resistance management
• Likelihood of livestock grazing.

Fungicides differ in their disease spectrum and efficacy. Mathcing the right product to the pathogen at the right timing provides a greater likelihood of getting a profitable return on investment.

The key foliar fungicide options available for use in chickpeas, lentils and faba beans are listed in Tables 3, 4 and 5 of the ADAMA Foliar Fungicide Guide for Winter Pulses (available for download below) along with important criteria such as their FRAC (Fungicide Resistance Action Committee) resistance group, type of activity within the plant and the relative strength against the key foliar diseases.

Rate Selection

Changing the application rate of foliar fungicides will alter the efficacy, disease spectrum and length of residual control.

Growers may choose to apply lower rates under lower disease pressure and/or when multiple applications are planned in a spray program.

If higher rates are to be used, growers must ensure they do not exceed the maximum number of sprays permitted for the season or the maximum combined product rate allowable per hectare as directed by the label or permit. This is to ensure there are not excessive residues in the grain or hay, as well as ensuring fungicide resistance management is considered.

Foliar Fungicide Guide for Winter Pulses

This post is extracted from the ADAMA Foliar Fungicide Guide for Winter Pulses. If you haven't already downloaded the guide, click 'Download' below for your copy.