Segway fungicide

Cyazofamid is a selective Oomycete fungicide discovered and developed by ISK Biotech. It is the active in Segway fungicide, which is a newer pythium control product on the Australian turf market and is in fungicide FRAC group 21. This means it is an ideal rotation option in any resistance management program. We think that any turf agronomist worth their salt will admit that this is the go to option if there is a problem with pythium.

For those who don’t want to read on here are the Segway Label and the Segway SDS. Segway is registered for use in both professional turf and lawn disease control and is available in 500ml and 1L pack sizes.

Being a Qil (Quinone inside Inhibitors) Segway controls Pythium diseases and attacks oomycetes fungi by respiratory inhibition at Complex III in the mitochondria. Segway inhibits all stages of the oomycete’s development and works as both a preventative and curative. The Segway fungicide label is in the turf chemical section.

Fungicide properties

Segway is long lasting giving 14-28 days of pythium control from one application. Once applied it locks onto waxy leaf surfaces, penetrating locally with translaminar mobility for excellent coverage, and is rainfast soon after application. The active, cyazofamid has low water solubility and good spreading properties on the plant surface.

Due to its excellent rainfast characteristics Segway Fungicide sticks to and remains where it’s needed so maximising its performance as a protectant fungicide.

Segway Resistance management

Although this is a new active with a new mode of action for the Australian turf industry now is the time to adopt a management strategy to delay the development of any resistance in the future. The US label states that Segway fungicide can be applied two times consecutively up to three times per year at the highest labeled rate, and six times per year at the lowest rate. This flexibility plus the fact that Segway has no known cross-resistance with other classes of fungicides make it an excellent option for resistance management programs. The table below shows a suggested application schedule.

Diseases controlled

Segway fungicide controls all pythium sp including:

• Pythium root dysfunction;
• Damping-off;
• Pythium root rot and
• Pythium blight.

Segway Fungicide Trials for pythium.

Trials into the effect of irrigation on Segway fungicide show that watering immediately after application results in a fivefold increase in cyazofamid residue (32.4% to 36% of the amount applied) in the 0-25mm soil depth. This compares delaying irrigation for six hours after treatment (5.3% to 5.5%).

Segway fungicide Label and Segway fungicide SDS.

Segway Fungicide for Pythium blight ( Pythium aphanidermatum)

Prevention of pythium blight

•  A trial at the University of wisconsin in 2021 shows that a Segway treatment 1 day before covering with Evergreen covers was the only treatment to provide acceptable turf quality.

Control of pythium blight

Pythium Root Rot

There in fact two different pythium root rot diseases which are caused by two different Pythium sp. On creeping bentgrass, root rot is called Pythium root dysfunction (PRD), and Pythium volutum causes this. However, on Poa annua, this disease is called Pythium root rot and is caused by many different Pythium species. The Pythium sp that cause damage to turf roots are different from Pythium aphanidermatum, which causes Pythium blight, a foliar disease.

As Oomycetes, they are also referred to as water molds and as a result, they tend to be a problem in periods of significant rainfall in the spring and summer.

The best treatment for Pythium root dysfunction is Segway which should be watered in following application to move it down into the upper root zone and crown area.

For Pythium root rot, there is not as much information on which treatments work the best, although there have been reports of Segway, Subdue, Banol, and Terrazole all working well.

Pythium Root dysfunction  (Pythium volutum and other pythium sp)

Preventative

• Cyazofamid gives moderate preventative control of Pythium root dysfunction.
• Autumn and spring applications of pyraclostrobin, azoxystrobin, and cyazofamid suppress Pythium root dysfunction symptoms during the summer. Pyraclostrobin is one of the actives present in the combination fungicide Lexicon Intrinsic.

Pythium Root Rot

Root rot favours periods of wet weather and symptoms appear as irregular patterns of orange and yellow hues.

Prevention

• This disease is worse where there is an excess thatch or in poorly drained areas. The key to managing it is to carry out regular cultural practices such as aerification, vertical mowing, and topdressing.
• Preventative applications need to be well-timed to manage Pythium root rot, so if you’re going to have many days of rain then it’s a good time to think about spraying.
• Trials have shown that preventative control of Pythium root rot is best achieved when cyazofamid is applied before the soil temperature has reached 24 ℃.

Curative control

• Cyazofamid performs well as a curative application.
• Applications at the low rate (2.8L/Ha) over 14-21 day intervals are as effective as applying the high rate (5.6L/Ha).