With more ground being put down to spring cropping this year, Farmacy is advising growers to pay close attention to plant growth regulator (PGR) requirements.
Alice Cannon, regional technical support manager for the East Midlands, explained that while most spring crops require at least one PGR application, both spring barley and oats will need two to reduce lodging risks as crops race through growth stages.
An early low rate of trinexapac-ethyl or chlormequat plus phosphates can help to improve tillering and root development, she added, something that could be beneficial given the delays and disruption with drilling.
Zinc, as well as biostimulants, can also assist root development and establishment.
Alice said that lodging risks are often greater on heavier soils, or in thicker crops, such as in situations where the seed rate has been increased to compensate for later drilling.
“Increasing the seed rate by 100 seed/m2 in spring barley increases the lodging risk by 1.5-2 points on the Recommended List rating. Where crops are being positioned in heavier soils or high-risk situations, then at least one PGR application should be planned.”
Spring barley has three potential application timings; T0 (growth stage 30), T1/1.5 (GS 31-32) and T1.5/T2 (GS 39), although the key timing is T1/1.5. Product choice should be tailored to the crop type, lodging risk and growth stage, and it should be recognised that the application cut-off date may differ for each product.
Between T1 and T1.5 is also the main application for oats, although growth stages will need to be monitored closely to ensure applications are not missed as oats can move through the stages very quickly.
“I highly recommend starting the PGR programme early to ensure you don’t miss applications as the product cut-offs are much earlier in oats. Also, be wary of end-market contract restrictions for certain PGR products,” Alice said.
As oats are more sensitive to chemical applications, she added that extra focus should be given to cultural controls to limit lodging, including careful timing of nitrogen applications, rolling and drilling dates. PGRs shouldn’t be mixed with herbicides when working in oats, as this could increase the risk of crop damage.
“You may find that spring cereals grown in the traditional light land situations, may not need a PGR application as lodging risk can be well managed with cultural controls.”
Alice concluded by reminding growers that anything drilled after the 1st of February is legally classified as a spring crop, and must be treated as such when planning inputs.
