Crop Protection



The new and unique solution for flexible and robust cereal disease control.

Questar™ is a new fungicide for the control of Septoria tritici, brown rust and yellow rust in winter wheat, winter triticale, winter spelt and durum wheat.

Questar is broad-spectrum fungicide containing Fenpicoxamid, more commonly known as Inatreq™ active. 

Inatreq active offers a new and unique site of action for curative and persistent protection against all Septoria strains. 

Questar MUST always be used in a mixture with a partner product which has a different mode of action.

For enquiries, contact Terrachem on: +353 87 254 7534 or email:, or call our Technical hotline:  +44 800 689 8899 or e-mail:


About Questar

Best Use Advice

  • Questar™ may be used on all commercial varieties of winter crops of wheat, triticale, durum wheat and spelt wheat.
  • Ideally apply at T2 to see maximum yield benefits but Questar could alternatively be applied at T1 if preferred.
  • Apply at the recommended rate of 2L/ha.
  • Questar will give the best results before the disease has become established in the crop.
  • Rainfastness is 1 hour for Questar.
  • Questar must always be used in mixture with a product with a different mode of action at a dose that offers robust control.
  • Before applying Questar we recommend visiting our Inatreq Sprayer Advice webpage for our best practice application advice and sprayer parts guidance. 

Resistance Management

Questar™ must always be used in mixture with a product with a different mode of action at a dose that offers robust control.

You must not apply more than one application of Questar to any cereal crop in the same year.

Questar should be used in accordance with the instructions for use for the target disease at the specific growth rate indicated.


Winter wheat

Winter triticale

Winter spelt

Durum wheat

Technical Specifications

Product Registration Number:
PCS 06465


Active Ingredients:
50g/L Fenpicoxamid (Inatreq active) (FRAC Code 21) 








Pack Size:
5 L
































Emulsifiable Concentrate (iQ-4 formulation)
Maximum Single Dose Rate:
2.0 L/ha
































Maximum Total Dose:
2.0 L/ha
































































Maximum Number of Applications:
1 per crop per season
































































Application Timing:
Beginning of stem elongation (GS 30)- end of flowering (GS 69)
































































1 hour 

Water Volumes:
100-300 L/ha

Aquatic Buffer Zone:
Buffer zone is determined by the STRIPE Water Tool but if the ditch is dry only a 1m buffer zone is required
































































































































®™Trademarks of Corteva Agriscience and its affiliated companies. Use plant protection products safely. Always read the label and product information before use.