Lexicon Intrinsic fungicide

Lexicon Intrinsic Fungicide is a highly effective turf fungicide. It gives long-term control of up to 28 days against a wide range of turf diseases whilst also offering advanced plant health benefits. These benefits are one of the reasons as turf agronomists we really like this product. It doesnt just kill turf disease!

This new fungicide has a dual mode of action and contains both pyraclostrobin and fluxapyroxad in a 1:2 ratio. Pyraclostrobin is also the active in Insignia fungicide. The Lexicon Intrinsic fungicide label and MSDS are in the turf chemical section. It can be used in both the professional and homegarden markets for turf disease control.

The fungicides in Lexicon  are in fungicide resistance groups 7 and 11 respectively and so Lexicon Intrinsic is also an ideal rotation option in any resistance management program.

Plant health benefits of Lexicon Intrinsic fungicide.

With its excellent disease control Lexicon also gives proven turf health benefits including:

• Increases in photosynthesis;
• Stronger root growth;
• Increases the ability of the turf to cope and recover from stress better;
• Improves the rate of couch grass vegetative establishment and sod shelf life.
• Enables turf in shade to better cope.

The majority of fungicides on the market give either a quick knockdown or a long term residual. Lexicon Intrinsic does both of these due to containing two highly effective actives. These are 333g/L pyraclostrobin and 167 g/L fluxapyroxad and are in fungicide Groups 7 and 11 respectively.

Pyraclostrobin is in fungicide Group 11 and is a quinone outside inhibitor-type fungicide, and stops germinating fungal spores and prevents them from infecting plant tissue. It also has some curative activity by causing fungi to stop growing and die.

Fluxapyroxad is in fungicide Group 7 and is a SDHI (succinate dehydrogenase inhibitor) and works by blocking plant respiration at Complex II and so blocks the growth of fungal cells. Fluxapyroxad works against a number of diseases but is excellent for the control of dollar spot.

Lexicon Intrinsic is very rainfast as it is tightly bound to the waxy leaf surface. Once it enters the leaf it moves upwards systemically though the xylem to unsprayed areas. This redistribution, along with its high level of activity, ensures long-lasting preventative and curative effects and results in reliable, more consistent disease control. Regarding the use of spray adjuvants with this I would strongly recommend not using an organosiloxane with this as it may cause turfgrass injury (as per the US label).

Diseases controlled

Research in the USA and Australia shows that this fungicide provides excellent control of 27 key cool and warm season turf diseases including:

• Anthracnose Colletotrichum graminicola
• Bentgrass dead spot Ophiosphaerella agrostis
• Bermudagrass decline* Gaeumannomyces graminis var graminis
• Brown patch Rhizoctonia
• Brown ring patch Rhizoctonia circinata var. circinata (previously called ‘Waitea patch’)
• Dollar spot Sclerotinia homoeocarpa
• Fairy ring various Basidiomycete fungi
• Fusarium patch Microdochium nivale or Fusarium spp.
• Gray leaf spot Pyricularia grisea
• Large patch Brown patch of warm season of turfgrasses, including Zoysia patch Rhizoctonia solani
• Leaf spot Bipolaris, Drechslera, and Exserohilum spp.
• Melting out Drechslera poae
• Necrotic ring spot* Leptosphaeria korrae
• Pythium blight Pythium aphanidermatum, Pythium spp.
• Pythium root dysfunction Pythium volutum, Pythium spp.
• Red thread Laetisaria fuciformis
• Rhizoctonia leaf or Sheath spot R. oryzea, R. zea
• Rust Puccinia and Uromyces spp.
• Spring Dead Spot Ophiosphaerella narmari
• Summer patch Magnaporthe poae
• Take-all patch Gaeumannomyces graminis var. avenae
• Yellow tuft (Downy mildew) Scleophthora

Lexicon Intrinsic Trials for disease control.

Several trials have shown that Lexicon Intrinsic fungicide gives excellent control of a variety of diseases, including brown patch, dollar spot, summer patch and fairy ring. In a trial on SR7100 colonial bentgrass, Lexicon Intrinsic showed 0% Rhizoctonia infection (brown patch) after 21 days, compared to the untreated control that averaged 70.5% disease incidence.

In a trial on “Baron” Tall Fescue, Lexicon Intrinsic showed 1.8% summer patch after 21 days. This compares with 58.2% on the untreated control.

Lexicon Intrinsic fungicide Label and Lexicon Intrinsic MSDS.

Dollar spot

Dollar spot control using Lexicon Intrinsic is both preventive and curative. Whether disease has actively begun to infect, or conditions are right for growth, fluxapyroxad will stop further growth when it contacts the fungi.

The numbers in parentheses denote the number of rating dates out of 13 when dollar spot lesions were fewer than five. Disease breakthroughs with Interface and Headway occured after 28 days. Applications were made on June 4, July 2 and July 30. Source: Dr. Rick Latin, Purdue University, 2014.

Lexicon Intrinsic for Pythium

BASF trials have shown that Lexicon gives better control of pythium than azoxystrobin + propiconazole (Headway Maxx label).

Root dysfunction

• Applications using pyraclostrobin provided superior preventative control of pythium root dysfunction compared with azoxystrobin (AzoForce fungicide label) and cyazofamid (Segway fungicide label).
• Azoystrobin and cyazofamid did provide moderate control of PRD in two of three seasons.
• Propamocarb did not work against pythium root dysfunction.

Pythium root rot

• Trials have shown that preventative control of Pythium root rot is best achieved when cyazofamid is applied once soil temperature have reached 24 ℃. Cyazofamid also performs well as a curative application.

Brown Patch on bentgrass

Spring Dead Spot (SDS)

Plant Health benefits

Turf quality

Turf quality readings with the last rating being taken 28 days after the last application. Applications of Lexicon Intrinsic were made on a 21-day interval on the 5/13, 6/3 and 6/24. Source: Dr. Bruce Martin, Clemson University, 2014.

Lexicon Intrinsic for faster grow in time and establishment

Lexicon pre treated sprigs on left, untreated on right down at Pinehurst Number 7 with the sprigs being treated 30 days and 5 days before sprigging. This is something you should seriously consider if you are sprigging and have a limited grow in window to get the turf etablished.

2020 work looking into harvest aids for improved couch sod shelf-life and transplant success has shown that Lexicon Intrinsic increases plant health characteristics of transplanted sod and may hasten the establishment of hybrid couch plugs.

Better root growth

One other plant health benefit of the use of Lexicon Intrinsic is that it improves root growth on both cool and warm turf species such as bentgrass or buffalograss.

Improved growth in shade

Research on shaded turf has shown that use of Lexicon Intrinsic improves turf quality.