Article taken from The Fruit Grower Magazine
By Clive Marlow
More than 70 delegates from Herefordshire, Worcestershire and Gloucestershire attended the Agrovista Technical Seminar held at Ledbury, Gloucestershire in February. Jane Antrobus of Agrovista welcomed the audience who were mainly producers of cider apples and perry pears.
Growers Choice Interactive (GCI)
The first speaker was Alex Radu, an Agrovista fruit agronomist, who gave an overview of Growers Choice Interactive (GCI), the internet-based pest and disease modelling service, and the improvements made during the past 12 months. Using live data from a network of weather stations the software provides indications of the risk of infections of scab, Fireblight, Nectria, codling moth and larvae activity. GCI is an invaluable tool for growers to time their pesticide applications. Alex also warned that Nectria canker was becoming a more important disease in cider orchards.
Pest and disease control
Paul Bennett, Agrovista's technical head of fruit, was next to take the podium and gave an update of the latest changes in legislation regarding pesticide use and the significant changes that will be necessary for spray programmes in 2016. These changes affect products such as chlorpyrifos, Aphox, phosphites and Captan. The current situation is that manufacturers have been advised that notices were being drafted that all products containing chlorpyrifos must be withdrawn from sale, distribution and use from March 1 2016.
New MRL restrictions came into force in early 2016, stating that, with immediate effect, Aphox should not be applied to apples, pears, blackcurrants, redcurrants, strawberries or cherries. Growers need to consult their agronomists to amend their planned spray programmes and to incorporate ecologically beneficial products. The main timings are: pre-bloom to control blossom weevil, caterpillars and rosy apple aphid; and post-bloom to control sawfly, capsid, caterpillar, mussel scale, nut scale and codling moth. Alternative products are available, with some cost implications. Phosphites have been used in UK orchards and the current legal position is:
• UK phosphite labels must make no fungicidal or biostimulant claims.
• Phosphite-use is purely to promote leaf, shoot and root development.
• All such products must be used legally. The position at present is that CRD and DEFRA have agreed that the low dosage of phosphite-use in the UK, and the fact that they are used as root and leaf promoters, means that they may be used as fertilisers and they fall outside of the EU biostimulant class.
The EU has imposed a blanket 75mg/kg maximum residue limit (MRL) while discussions continue. On 1st January this year the MRL reverted to 2mg/kg on some crops, but apples, pears and strawberries remain at 75mg/kg. However, stone fruit, bush fruit and cane fruit reverted to 2mg/kg, which is the limit of detection (LOD). It is important to bear in mind that discussions are ongoing and that further changes may follow. Cider processors will take a view as to how many phosphite applications have been made to a crop. Paul was also of the opinion that in the foreseeable future the industry could lose glyphosate.
Nutritional requirements of cider apple production
This subject was covered by Jane Antrobus. She began with the statement that higher yields can often be achieved by increasing fruit size rather than by producing more apples. An increase of more than 10% can be gained by increasing the size of the fruit from 40mm to 44mm. Starting with the soil, the ideal pH for cider apple production is in the range of 6.3 to 6.8, cider apples preferring a slightly acidic soil.
A good healthy soil improves the uptake of minerals. Jane posed the question, ""Why consider additional nutrition for cider apples?"" Firstly, it strengthens the tree vitality for continual cropping, and increases the size of the fruit. Secondly, strong trees are able to withstand pest and disease pressures. Foliar applications aid the overall nutrient ratios, resulting in higher yields and greater profit. In early spring, two to four weeks before flowering, nitrogen should be applied to boost the growth of the trees. This must be applied before the petals have opened and as 50% nitrate plus 50% ammonium. This will be available for longer and will help leaves to grow, increasing the chlorophyll content and improving photosynthesis. Post-flowering is the time to assess fruit-set — if the set looks high an additional nitrogen application should be considered. Nitrogen applied at this stage helps with cell division and aids tree vitality. Also important is leaf analysis during June, which can identify potassium deficiency. Soil analysis can show that potassium is adequate, but it may be locked in the soil, so leaf analysis is the surest method of identification. In summer nitrogen deficiency can cause small leaves, and an application of nitrogen in nitrate form should be made immediately. Around 21 June fruit cell expansion should be encouraged by ensuring that the tree has sufficient water. The application of nitrogen after harvest and in the autumn will pay dividends for the next season's crop.
A cider-maker's view
This was given by Allen Hogan, a cider-maker based in Warwickshire who presses 300 to 400 tonnes of cider apples and 20 tonnes of pears, exporting his cider and perry to ten countries around the world. In his thought-provoking presentation he highlighted the anomalies of the tax system. There is no duty payable on the first 7,000 litres of cider produced, but once 7001 litres are produced, duty is payable on every litre. For this reason the majority of the 480 cider-makers in the UK are small. The industry presses about 250,000 tonnes of fruit per annum, 200,000 tonnes of which is bitter-sweet cider varieties and 50,000 tonnes is culinary varieties. However, based on the current annual consumption of 1,500 million pints, UK apples account for only 30% of cider consumed. There was lively audience participation and Allen conceded that cider-makers had not always communicated well with growers. He said that what cider-makers wanted was cider apples and perry pears with a good balance of tannin, sugar and acidity. Early varieties were preferred and the fruit must be clean and free from foreign bodies.