Technical and Marketing Workshop 2012
Introduction Crop Protection Programs Fruit Production-Tree Health management Dave McLellan Guest Speakers Gro Chem Steve Huxstable & Greg Evans Market Outlook & General Discussion Ian Albers, Phil Croy, Stuart Mansill, Robert Schroder & Brian Pepper
Insecticides Resistance issues have ruled some chemistry ineffective-use new chemistry at label rates Whitefly and its close relation Mealy Bug are renowned for being some of the fastest pests to develop resistance to new chemistry A mixture of old and new chemistry, broad spectrum and targeted products and a range of active ingredients considered best for effective control and preventing resistance developing
Example Insecticide Program October (post pruning) Copper + oil (.5%) November (post fruit set) Mag-nitrate November (before 30 th ) Dew + oil (1%) December Mag Nitrate December Mancozeb Rust Mite + Fungicide December (pre Xmas) Movento January (before 31 st ) Movento March/April/May Success/Fyfanon/Buprofezin Pest specific dependant on monitoring results
Spray Diaries, PHIs & MRLs Spray Diaries are not an optional extra! These need to be submitted 4 weeks prior to harvest. PLEASE NO DIAZINON after November Check PHI before you spray Is there alternative product if outside the PHI? Check with Dave if in doubt. Where is my crop going? Check with product managers if in doubt. MRLs - Scientists can now detect one drop of chemical in an Olympic size swimming pool. (Unless you re an international road cyclist).
Disease and Fungicides This season we had over 1000 mm of rain between fruit set and harvest (December to August) compared with an average of just over 700 mm (NZCGI figures). During the 151 day period of cell expansion and fruit growth stage (December April) it rained on 77 days. A number of growers were caught out early without fungicide cover on young fruitlets and spent the rest of the season chasing infection. Fruitlets are most susceptible to infection during the first 10-12 weeks following fruit set.
Fungicides Fungicide programs traditionally based around mainly copper applications (timing crucial - copper a protectant) Mancozeb formulations are effective and are also used to control Rust Mite from December to January and Bud Mite in April. Mancozeb also contains a source of Manganese. USA usage of Mancozeb alright due to its chemical group (Dithiocarbamate) including a US product Ferbam as long as under MRL for Ferbam. Those with a history of Rots, Melanose, Alternaria, Melanose or Glomerella should be applying protectant copper applications pre and post flower
Melanose Melanose affects most varieties. Symptoms vary from small raised scabs to large smooth areas resembling rust mite damage and tear drop to fly spec patterns. Spores live in dead wood and release during wet conditions to infect young leaves and fruit Young fruitlets are most susceptible and Oranges appear resistant once they achieve 40mm diameter. Can be hard to see early infections against dark green of fruitlets.
Melanose symptoms are varied
Melanose Prevention Copper is the mainstay of Melanose prevention but Phaltan and Serenade Max also have label claims for it. Crucial stage is the 12 weeks from petal fall as young fruitlets are most at risk. Copper spray before blossom opens and again at ¾ petal fall will ensure good coverage of young fruitlets. A further application after 3-4 weeks can be made, (only if wet weather conditions dictate).
Alternaria-Brown Spot Alternaria rot is a fungal disease that affects mainly navel oranges and lemons. The disease itself often doesn't develop until after harvest and most damage occurs during storage but infection happens in the orchard. It is also called black rot, and results in dark brown to black, firm spots or areas mostly around the navel in oranges. If you cut the fruit in half, you can see the rot extending into the core.
Alternaria found off-shore
Alternaria Prevention Mancozeb has a label claim for Alternaria. Copper Hydroxide & Copper Oxychloride also control. The use of the growth regulator 2,4-D (Stop Drop) delays senescence and thereby restricts colonization of the host as well.
Citrus Blast Young growth not hardened off before winter most susceptible. Injury to tissue occurs during driving rain and wind allowing bacteria to enter tissue. Several days of rain is needed for infection to occur. Needs temperatures between 8-18oC to reproduce Lemons and Mandarins most susceptible Copper applications control
Citrus Blast found off-shore
Phosphorous Acid Applications Phosphorous Acid (Foschek, Phosgard, Perk etc) Combination of Phosphorous (Phosphorous Acid) and Potassium (Potassium salts) Phosphorous is the trace element for root health and development Systemic activity can last for 8-12 weeks Extremely effective (due to its systemic nature) of controlling Brown Rot or Root Rot (Phytophthora)
Phosphorous Acid and Potassium N P K Perk Supa 0 23 38 Phosgard 0 28 25 Phosgard + 0 32 25 Foschek 0 11 16
Fruit Marking Theories Reaction of Limonene (oils) to high doses of P or K coupled with extreme weather which triggers reaction. Tree stress due to excess water and wet roots. Reaction to higher K levels in Perk as damage not observed by those using other products (but Perk most popular)
South African Phos 400 SL Label
Phos Acid Recommendations Avoid using during winter months (June-August) It is systemic for 8-12 weeks so an application late May should cover coldest months. Better used as a preventative than curative. Consider use of Mancozeb or Copper as alternatives during winter months (but leave 4 weeks between Phos Acid and Copper sprays) If necessary to use in Winter due to rots, consider skirt sprays targeting bottom 1m. Too many applications can lead to a nutrient imbalance causing Zinc deficiencies. Maximum of 3 applications per season.
Improving Fruit Quality of Gisborne Citrus Tree Health. Tree/Crop Management. Harvest Management.
Improving Fruit Quality of Gisborne Tree Health. Citrus Key factors affecting tree health are Soil conditions Tree nutrition Irrigation
Gisborne Soils Mostly heavy soil types, heavy silt and clay loams. In general, most plants grow by absorbing nutrients from the soil. Their ability to do this depends on the nature of the soil. Depending on its location, a soil contains some combination of sand, silt, clay, and organic matter. The makeup of a soil (soil texture) and its acidity (ph) determine the extent to which nutrients are available to plants.
Know your soil Soil ph (a measure of the acidity or alkalinity of the soil) ideally should be between 6.0-6.5 Soil ph is one of the most important soil properties that affects the availability of nutrients. Macronutrients tend to be less available in soils with low ph. (Nitrogen/Phosphorous/Potassium/Sulphur/Calcium and Magnesium) Micronutrients tend to be less available in soils with high ph. (Boron/Copper/Iron/Manganese/Molybdenum/Zinc)
Boeyen Case Study
Boeyen Case Study
Boeyen Case Study
Boeyen Soil test results
Irrigation Citrus feeder roots are only found to about 400mm below the surface and therefore any watering below this zone is not assisting the tree. Pulse irrigation rather than flood irrigating the root zone is recommended and flooding citrus roots can possibly cause anaerobic conditions in the root zone leading to disease such as Phytophthora. Irrigation Monitoring is important to avoid stressing trees by improper irrigation (e.g. flood then drought) and ideally the water level should remain between the full and trigger points.
Irrigation Monitoring
Pulse v Flood irrigation only top 400mm needs water Moisture level below 400 has not changed in 2 months
Improving Fruit Quality of Gisborne Citrus Tree & Crop Management. Key factors affecting tree health are Crop Loading Thinning (Chemical and Hand)
Fruit Size Management Calendar & Checklist
Crop Load and Size Management of Navel Oranges Based on Australian data and being modified to New Zealand conditions Measurement of fruit in February (NZ) can calculate fruit size at harvest (eg Fruit at 40mm mid Feb will be 70mm at harvest Thinning timing: Frame counts in January - Navels aiming for 10-12 fruit per ½ m 3 Sizing in Mid February - any fruit <35mm should be removed
Fruit Size Prediction Model Based on initial work with Washington Navels
GA Sprays-Navels GA can be applied to navel oranges to: Improve rind firmness, quality and decrease incidence of: Oleocellosis, Albedo breakdown (creasing) and Postharvest rind breakdown as well as: Extending postharvest shelf-life and slowing down rind colour development and delaying harvesting It can also be used for Flower manipulation and size enhancement (used going into an on year to turn floral buds into leafy inflorescence) to create a greater ratio of leaf to flower Depending on which effect is sought, separate GA applications and timings are required.
GA Sprays-Application timings Summer GA: to improve rind quality and market outturn A GA spray at 10ppm applied when the majority of the fruit are 30 50 mm in size in summer (February) is recommended for navel oranges (especially for export markets) to reduce the incidence of rind disorders such as: albedo breakdown (creasing) water spot or Oleocellosis postharvest rind breakdown Winter GA: to reduce flower buds and improve size A GA spray at 25ppm applied in Mid June (same timing as used for Satsumas) during the floral induction phase has been shown to suppress flowering and increase size leading to increased returns in excess of $2000/ha due to improved size profile. (NB only to be used if going into an on year)
Naphthylacetic Acid (NAA/ANA) Used for thinning traditionally Research re sizing showed benefits on Navel Oranges when applied in Late December (targeting fruitlets at 16-20mm average) International research also shows decrease in creasing and better fruit finish as well as size enhancement and assists with alternate bearing NZ research shows higher brix and 67% of fruit size >70mm compared with controls at 51% Smoother fruit finish (less creasing) An addition to GA and Calcium applications
THINNING One of the main costs of production for growers is the expense of hand thinning. Hand thinning allows grower s to achieve the right crop load for a given variety. For Satsuma's hand thinning should take place between mid December and the end of January (depending on variety) For Encore commence hand thinning in February once natural drop and chemical thinners have finished working
Chemical Thinning ANA/NAA100 Satsuma and Encore mandarins can be successfully thinned with the chemical ANA (NAA100). ANA and NAA100 are identical products both containing the same active ingredient at the same rate. ie 100g/l Naphthylacetic Acid A rate of 300ppm (300mls/100 litres) is applied as a dilute spray when the young fruitlets are averaging 12 mm in diameter Thorough coverage of all fruitlets is important. Water rates should vary to match tree size and density. It is critical temperatures on the day of application and for the following two days reach at least 20 degrees (25 is better)
Encore Crop and Size Monitoring College Road block-encore 4 years old Trees chosen at random 10 th tree each row 20 fruit per tree tagged, measured and recorded each week commencing 1 September Crops thinned February Trees carrying average of 280 fruit/tree (Range 16 690 fruit/tree) Average size of fruit 54.9 mm (1 st September)
Average size fruit 28 Sept = 56.5mm Growth (4 weeks) = 0.42 mm/week Trees then picked 28 September Measured 24 October (4 weeks after pick) Average fruit size 24 Oct = 59.3 Growth 28 Sep 24 Oct = 0.7mm/week Pricing during this period 55mm = $1.30-1.40/kg -v- 60mm+ = $2.00/kg
Improving Fruit Quality of Gisborne Citrus Harvest Management. Key factors affecting harvest management are Liaison with marketers Timing of Harvest Harvest Supervision and Quality Control
Harvesting Supervision & Quality Control Despite a challenging growing season there was a definite improvement in the quality of Satsumas presented for packing last season compared to the previous season. While there were some very well presented lines of fruit there were still lines where picking related defects were high and cost growers money needlessly. A contributing factor for this high level of damage is poor training and supervision of picking teams. While some fruit that has been cut by clippers will inevitably end up in the juice bin it is actually the difference between TAG 1 and 2 that can be the most expensive for the grower. A simple long stem can reduce the value of the fruit by up to 60% depending on the season.
Harvesting Supervision & Quality Control Case Study One grower (Tony Cornelius) this year extensively used a QC (Jenny) and the First Fresh QC sheets. There were some 26 pickers picking at his property, a daunting task for any grower. The use of the sheets identified two pickers consistently damaging fruit and allowed for these pickers to be managed to ensure the quality of their work improved or they were removed to avoid further damage to the crop The results were very good with the pack house TAG1 average for Miyagawa sitting at 81.5% Tony achieved a TAG1 average of 88.5% The difference was not in the reject or juice grade which both ran at 6.3% but in the difference between TAG1 and TAG2 which the grower was able to minimise and keep TAG2 at 5.2% while the average for all growers in the pack house was over 12.1% The difference in return between TAG1 and 2 was $0.65/kg and represented an extra $4500 return to the grower for his efforts.