Stress relief in flowering maize to boost cob size and yield

Syngenta technical manager, Andy Cunningham, outlined: “Crop stress during the reproductive stage of maize deteriorates both the number of kernels set on each cob, and their quality.

“That typically occurs around the 9 to 10 leaf stage in maize and will set crop quality for feed or biodigestion.”

Under moderate heat stress pollen tube germination is restricted, with a higher proportion of sterile anthers, he warned. “Maize is particularly susceptible to heat stress at this stage. Application of Quantis prior to the tetrad stage helps to protect pollen development and successful fertilisation.”

Quantis field trials

Split field trials in Shropshire last year, with Quantis application at the 9-10 leaf stage on a crop of LG Prospect, increased cob weight by an average of 22% in the treated crop, with an average cob length of 17.25 cm, compared to just 15.75 cm in the untreated.

As a result, the treated crop yielded 35% more dry matter, at 16.48 t/ha, compared to 12.21 t/ha in the farm standard agronomy programme, Andy reported.

“Using Quantis to protect maize plants through stressful periods enables the crop to function more normally, and so protect yield,” he advised.

Andy advocated that all crops should receive an application of Quantis at 2.0 l/ha prior to the sensitive tetrad stage, which occurs around the 9-10 leaf stage, with further applications if the crop is subjected to significant heat stress events during the cob and grain fill stages.

“Maize is generally more resilient to higher temperatures through the growing season. However, if sustained temperatures over 30⁰C do occur – as has increasingly been the case in recent seasons – significant reduction in the plant’s activity and performance can occur.

“Quantis application prior to heat events has been shown to help plants to better cope with the conditions, as well as to recover faster without long-lasting effects.”

The Quantis Heat Stress Forecast tool is available free to growers and agronomists as part of the Syngenta myFIELD digital platform. It provides warnings of potential heat events on a field-by-field basis, in time to take necessary action, with a maize specific heat stress guide in development. The myFIELD App is available for download and to register from the App Store or Google Play.