Forage: Phytophthora Root Rot (Phytophthora medicaginis)

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Pub 812: Field Crop Protection Guide > Chapter 3: Forages > Phytophthora Root Rot

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Field Crop Protection Guide 2011-2012, Order 2011-2012 publication

Table of Contents

1. Integrated Pest Management Options
   • Seed Treatment
     • metalaxyl-M – Apron XL LS
     • metalaxyl – Allegiance FL, Apron FL
2. Related links...

Integrated Pest Management Options

Seed Treatment

Plant resistant varieties that are treated with metalaxyl or metalaxyl-M. Consult with your seed company and the Ontario Forage Crops Committee Variety Trial Results at www.uoguelph.ca/plant/performance_recommendations/ofcc/ofcc.htm for variety profiles. Drain excess moisture from soil and avoid compaction. Avoid other stresses such as insects, weeds and untimely cuttings that may stress the plants and make them more susceptible to Phytophthora. Do not cut during wet conditions. Crop rotation has little affect on the disease. Promote lateral root growth by following a good fertility program.

Active ingredient	metalaxyl-M
Trade name	Apron XL LS
Rate (product)	40 mL per 100 kg seed
Comments	For use in commercial seed treatment facilities only. Do not use in hopper-box, planter-box, slurry-box or other non-commercial seed treatment applications at or immediately before planting. Do not graze or feed livestock on seeded area for 4 weeks after planting. Read label for information regarding resistant strains of fungus.

 

Active ingredient	metalaxyl
Trade name	Allegiance FL
Rate (product)	46-110 mL per 100 kg seed
Comments	Do not graze or feed livestock on seeded area for 4 weeks after planting.

 

Active ingredient	metalaxyl
Trade name	Apron FL
Rate (product)	46-110 mL per 100 kg seed
Comments	Do not graze or feed livestock on seeded area for 4 weeks after planting.

 

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Related links...

• Agronomy Guide for Field Crops - Publication 811
  • Forage: Phtophthora Root Rot
• Diseases
• Forages