CROP CRACK - 29.09.07
By WENDY FEARON
Clarendon Agricare - Winter Drilling Underway

The weather over the past week has unfortunately turned more autumnal and the heavy rain has resulted in deteriorating soil conditions severely hampering autumn cultivations and other fieldwork.

Most main crop potatoes have now been desiccated and successful harvesting and storage is the main aim.As ground conditions deteriorate this becomes an increasingly difficult job.Harvesters should be carefully set to minimise damage to the crop as damaged tubers allow easier infection by storage diseases.

Grass reseeds should be inspected for weeds and pest damage and treated where necessary while ground conditions still allow.

WINTER CEREALS

Winter barley drilling has begun in most areas with the acreage well up on last year. Both winter barley and winter wheat seed are very scarce. Winter wheat still remains the most profitable crop option.

Most of the autumn herbicides we have been familiar with are still available for this year, with the introduction of some new chemistry.PICONA which is a mix of pendimethalin and picolinafen may be applied to both winter wheat and winter barley pre-emergence up to GS 30 of the crop. Some LIBERATOR will also be used this season and may be applied up until the end of December on both wheat and barley.

All residual herbicides will be compromised with current high temperatures as persistency is linked to soil temperature. As soil temperatures drop persistency will improve, although AMG is best controlled when just emerging.

BARLEY YELLOW DWARF VIRUS (BYDV)

BYDV is a virus disease passed on to the crop by aphids when they feed on the young plants in the autumn.  Once plants are infected nothing will prevent the development of BYDV and therefore it is essential to use preventative measures by applying insecticides at the correct time, usually with a herbicide.

Inspect your crops regularly for the presence of aphids and apply either SUMI- ALPHA or TOPPEL in October or early November or when aphids are first seen in the crop. 

POTATOES

As storage diseases such as gangrene and dry rot cause infection mainly through wounds, keep damage during harvesting and grading to a minimum.  These diseases plus silver scurf and skin spot can be controlled on seed potatoes with imazalil (FUNGAZIL). It is advisable to check with your customer before applying a fungicide, particularly to ware.

Apply the fungicides as soon as possible after lifting to achieve the most effective control.  Their efficacy is reduced if there is excessive soil on the tubers as the fungicide for optimum effect needs to make contact with the tuber skin.

Sprouting can now be controlled in ware potatoes during storage with granules of Mss CIPC 5G.Previously it could only be applied as a fog through a specialist machine hence restricting its use to very large stores. This is an ideal product for smaller storage facilities where fogging is not an option. Only clean mature and disease free potatoes should be treated.CIPC 5G should be applied when sprouts are more than 0.5mm on inspection during the storage period. It will kill the growing points and further growth will cease. Potatoes must be dry, cured and the skins set before application.CIPC5G must not be used on a seed crop.