We’ve not got as many apples and plums as last year, but the pears are pretty good and the rain over the summer has not only helped the wheat and barley harvests but also the fern growth on our asparagus which is much bigger than last season.
As we’ve only got a small area, we’re able to practice good crop hygiene and remove all the old fern and reduce the amount of inoculum on the old stems so our stemphylium levels are very low.
The hot wet weather during June and July has had some interesting effects in the potato crops, particularly in the East. Botrytis and sclerotinia are evident in many fields and will now be having some effect on yield. Hot wet weather during flowering (in the high 30degCs) with heavy rain and thunderstorms were the perfect conditions for infection.
Sclerotinia is particularly found in rotations with carrots, parsnips and brassica species and is pretty evident with the broken stems, large white lesions and the black sclerotia when the stems are split open.
Botrytis is less distinctive and can be confused with blight, but has still caused early defoliation in some fields. Whether it’s the season or the lack of fluazinam in the blight programme is not clear, as it has an effect on both diseases.
So there may be justification for more fluazinam use in 2020 around flowering - even with the issue with Dark Green 37-A2 and its reduced sensitivity.
As we know it’s the last season of use of diquat and it will be the first time many growers will be looking at flails in their management systems.
Many crops are well advanced and their haulm is senescing much more than usual at this time of year.
This means we should expect a bit easier time regarding haulm management than a more normal season, but lessons will no doubt be learnt.
We have our own demo of flailing and haulm management without diquat at our Fen demo and trial site at AL Lees later in September and will be interesting to see what that shows.
Beet has also been affected by the hot weather and many crops on lighter soils have wilted and the outer leaves have scorched. This meant, when the thunderstorms arrived, the beet stood up again and now many crops are showing yellow symptoms, but not all caused by virus.
This wilting is not confined to very light soils and needs some further investigation to find out what’s actually going on, as it may not be just drought.
Flagging beet crops can often be a sign of Beet Cyst Nematode (BCN) and the poor, stunted root systems cannot take up the water required for the crop and wilt earlier and longer than other parts of the field. A walk with a spade or a trowel can be a useful thing to do looking for the stunted and hairy root system with the white, lemon-shaped cysts attached.
There are several BCN tolerant varieties on the RL list including Daphna which is the top yielding variety so identifying issues now influences how the crop can be manged more effectively in 2020.
It wasn’t that long ago that British Sugar advised against beet and oilseed rape in the same rotation due to BCN build up, as BCN affects both beet and oilseed rape.
Many poor areas of oilseed rape can be affected by BCN and looking at the roots can reveal those white, lemon-shaped cysts. So, its important to identify any issues as it can affect more than one crop in the rotation.
Secondary infections of rust, mildew and cercospora are now being seen in crops so a second fungicide needs to be applied, especially for later lifted crops and treatment should start as soon as disease is seen on the plants.