Gout fly eggs were seen in profusion this autumn and were found in area where previously unseen. This pest, unlike WBF which invades one tiller, feeds then moves on to the next and so on, simply invades one tiller and remains there. The symptom to look for is a tiller swollen at the base (hence the name - gout fly) resembling a spring onion. Easily treated with a systemic insecticide but rarely economic to do so, the damage is not usually yield threatening. However, with such high egg numbers, total damage may be high this season.
Spring drilling
Some are still out there carrying on sowing winter wheat following roots (where soil conditions allow, a rare thing this spring, although drilling into frosts has been achieved over some acreages), spring wheat will in all but exceptional circumstances give better returns from February sowing than winter varieties. They are more vigorous, establish better (particularly in poorer seedbeds) than winter wheats and produce more leaf giving better light interception. Maturity is around the same time as conventionally drilled winter varieties. Spring wheats tend to produce milling quality reliably and can therefore often attract a premium.
Latest safe sowing dates
Status early April
Ashby mid April
Belvoir mid April
Chablis mid April
Shiraz mid April
Samoa end April
Alder end April
Seed rates should be around 350 seeds m2 from now until mid March for reasonable seedbeds (adjust up 30-40 seeds for poor seedbeds, down 30-40 for good seedbeds).
Winter barley
There are some very lush barley crops around the country, many with far too many tillers to support, also there are some fairly backward crops too. Over thick crops will increase management time, disease and lodging risk and potentially reduce yield and grain quality. The best thing to do with crops that are too tillered is leave them alone. Don’t be tempted to apply nitrogen too early, as this will encourage tiller survival. You will need, for a 2 row barley, somewhere in the region of 900-1200 ears/m2, for a 6 row 700-900 ears/m2. More than this and specific weight will begin to drop, screenings, disease risk and lodging risk will increase.
Less well developed crops will need some nitrogen in mid March to ensure tiller numbers are maintained or increased to give the ear numbers needed. About 30 - 40kg ha –1 should be enough, then wait for GS 31/32 (around early to mid April) before applying anymore.
An application of PGR at GS 27/29 to even up the tillers (and maybe encourage better rooting) is recommended.
Don’t forget the sulphur. As with wheat, barley requires sulphur and the soils are not now supplying enough in most areas. About 15kg S (37kg SO3) should be enough in average yield situations. Yield and grain quality (particularly screenings) will suffer in sulphur deficient situations.
In general crops weren’t carrying a high disease burden in the late autumn and that has in most cases been reduced considerably as older and infected leaves have been killed off by the frosts and cold winds over Christmas and through January.
However, both net blotch and Rhynchosporium can be found and have the potential to re-infect crops quickly. Both are extremely difficult and expensive to eradicate once established (although the newer strobilurin products are more active on both diseases than some of the older fungicides). Better and cheaper to control them early with a T0 fungicide if it looks like they may become a threat later in the season.
Mildew is present in almost every variety looked at so far but at low levels and whilst not a concern at the moment, could become a serious threat. Monitor crops regularly and if it develops before the T1 spray timing, it may justify a fungicide.
Eyespot is not a disease usually considered in barley, but actually we believe it is responsible for considerable yield losses in recent years. Consider a fungicide with eyespot activity at T1 (and use at rates that will actually have an effect).
Oilseed Rape - February 2003
Crops are variable this spring, some well advanced but many quite backward with small plants, mainly due to the dry period in September, from which they never seemed to recover. What we need now is a little mild weather to encouraging new growth. As we seem to see so often these days with the mild open autumns and winters, the disease threat remains very high, so fungicide programmes should be considered and with poorly rooted crops and the possibility that soil nitrogen will have been moved lower in the profile by the wet weather, fertilizer spreaders should be retrieved from the back of the barn and made ready to go so some nitrogen can be applied to be immediately available when growth does restart,
Disease
LLS levels has increased dramatically in recent weeks, notably in the north but high levels have been found in all parts of the country including the South and South East and East Anglia where it isn’t traditionally a problem. Keep a watchful eye out as the weather becomes milder as LLS can develop very quickly. LLS is historically one of the most important diseases in oilseed rape and can reduce yields by up to 1.5 tonnes/ha. Effective control is achievable but once established it is expensive to eradicate. Autumn fungicides will be running out of steam so be prepared to go again soon, and be prepared to use effective rates.
Phoma has been a problem all season. High levels in the autumn in almost all areas of the UK have translated into high incidence in the spring, particularly in the south east. With such small plants in so many crops, Phoma will migrate down leaf stems and into the main stem rapidly, so be ready to treat crops at short notice. Phoma can cause huge yield losses if left untreated and must be put high on the list of priorities if found in the crop.
If an autumn fungicide was used, disease levels will have been reduced but it remains vital to use a spring application if either disease is identified. Go on with applications sooner rather than later. If no autumn fungicide was applied then the likelihood is that either you are very lucky and have a clean crop or that there are some potentially damaging levels of disease in your crop. A high rate of fungicide (at least ¾ rate if not full rate) should be applied as soon as conditions allow. In bad situations follow up with another, lower rate, in a month’s time.
Fertilizer
As mentioned at the start, small backward plants will have a poorly developed root system not able to scavenge nitrogen from the soil. Application of some early nitrogen will improve availability and allow crops to get away well when warm weather arrives. It is best to split total seasonal applications into 2, or if using very high rates, 3 applications. Apply the first when ground conditions allow, before the end of February, and the last split as late as is practical (i.e. before the height of the crop interferes with the accuracy of spreading).
It’s a similar story with sulphur availability. The importance of Sulphur to any crop cannot be emphasized enough. Sulphur is a major nutrient required for any plant growth and deficiencies will not necessarily manifest themselves as a physical symptom, at least not until it is too late. OSR is no different. Sulphur is required in large quantities from stem extension through to grain fill. Most will be able to recognize the symptoms as the pale yellow, small petalled, flowers, but it is much too late to do anything by then.
Atmospheric deposition of sulphur has reduced considerably over the last 10 years and the amount of available Sulphur in the soil is decreasing at a high rate. Most soils should now be considered deficient.
High yield potential crops should receive adequate sulphur to allow them to achieve their full potential. A 5 tonne crop will require up to 55kg S (140kg SO3) applied in the spring. 35kg S (85kg SO3) will still be required by low yield potential varieties have been sown.
The most reliable way to provide this is by using Ammonium Sulphate. Elemental Sulphur needs to be broken down in the soil and converted to Sulphate to become available to the plant. This is temperature dependent and can make availability unreliable.
Sulphur availability will determine the amount of nitrogen the crop is able to take up. If sulphur is limiting it will ‘cap’ the nitrogen uptake. Any nitrogen applied above that amount will not be utilized by the crop and will probably end up, like the yield and your money, somewhere down the drain.
Case Study
Since the Stone Age, farmers have understood that it was possible to make a plant or animal by
Selective breeding.
Selective breeding means choosing the animals with the characteristics you want to breed with because they probably have the genes you want to pass on.
So, if you want sheep with larger bodies, but less fatty meat, you select parents which are most like the offspring you want. If you keep repeating the same selection year after year, then you increase the proportion of the genes you want.
Here is an example
If you were an early sheep farmer with a flock of Mouflon, what would you look for in the parents of next year’s lambs?
In different parts of the world, sheep farmers have selected different characteristics. For example, Sheep in the Yemen have been selected over many generations for wool which is suitable for making carpets.
In hilly and mountainous areas, sheep have tended to be breed which are lighter and more agile.
As a result of many different farmers needs there are numerous breeds of sheep.
