Terpal
A plant growth regulator for late season use in winter wheat, winter and spring barley, triticale and winter rye. Terpal® is the tried and tested industry standard, delivering stem and root lodging resistance, and is an invaluable tool for protecting yield and quality.
Benefits
- Increases resistance to stem lodging by one point and resistance to root lodging by almost two points (Source: ADAS)
- The best product to reduce brackling in barley
- Co-formulation of mepiquat chloride and 2-chloroethylphosphonic acid in an SL formulation
Why Terpal?
Why Terpal®?
Terpal® is a soluble concentrate containing two active ingredients - mepiquat chloride and 2-chloroethylphosphonic acid. The growth regulator can be used to protect yield quality in winter wheat, spring and winter barley, triticale and winter rye. Particularly in barley, Terpal® reduces brackling, which is key to protecting yield, quality and enhances harvest efficiency.
A major benefit of Terpal® is even crop quality, achieved by balancing main and side tiller height and preventing lodging. Terpal® improves ease of harvesting and maintains grain quality. In addition, Terpal® counteracts crop stress from ethylene production; this is a problem with straight 2-chloroethylphosphonic acid (ethephon) which can impact yield.
Product Profile
Active ingredient(s) | 305 g/l mepiquat chloride + 155 g/l 2-chloroethylphosphonic acid |
Formulation | Soluble concentrate (SL) |
Pack size | 5 litres in outers of four |
Crop(s) | Winter wheat, winter and spring barley, triticale and winter rye |
Maximum number of treatments: Winter wheat and winter barley | Two per crop (as split dose) |
Maximum number of treatments: All other recommended crops | One per crop |
Maximum individual dose: Winter wheat, winter barley, triticale and winter rye Spring barley | 2.0 litres per hectare 1.5 litres per hectare |
Maximum total dose: Winter wheat, winter barley, triticale and winter rye Spring barley | 2.0 litres per hectare 1.5 litres per hectare |
Maximum number of treatments: Winter wheat and winter barley All other recommended crops | Two per crop One per crop |
Latest time of application | See label |
Water volume | Minimum of 220 litres per hectare |
Aquatic buffer zone | None |
Other specific restrictions | Maximum total dose must not exceed 2.0 litres product per hectare when applying split dose applications to winter wheat and winter barley |

Terpal® - the best PGR for late lodging protection
Terpal® applied at GS32-39 in cereals can significantly increase the lodging resistance score of high risk crops and is the best choice PGR to protect yield late in the season.