Light leaf spot forecast

Producing more than one infection cycle per season, light leaf spot is an important disease of winter oilseed rape. Although chemistry is available, sufficient control often depends on a combination of cultural measures and well-timed sprays.
How to manage light leaf spot in oilseed rape

Issued each autumn by AHDB, the preliminary light leaf spot (LLS) forecast shows the proportion of the oilseed rape crop (disease resistance rating of 5) estimated to have more than 25% of plants affected by LLS in the spring for the current season. The forecast uses previous season pod incidence data and deviation from the 30-year mean summer (July and August) temperature. It also uses historic average winter rainfall data. In spring, the forecast is updated to reflect deviation in actual winter rainfall data from the 30-year mean.

The forecast provides a guide to seasonal risk levels. However, as local risk varies, it is important to inspect crops on a field-by-field basis, with prioritisation on early-sown susceptible varieties.

2020/21 (preliminary)

0–14%

15–29%

30–44%

45–59%

>60%

Read the news release about this research

Light leaf spot final forecasts (2013–20)

2019/20

2018/19

2017/18

2016/17

2015/16

2014/15

×