Dr. Danielle Hirkala BC Tree Fruits Cooperative

Transcription

1 Replant Orchard Analysis / Bioassay Test & Replant Advisory Service (RAS) Dr. Danielle Hirkala BC Tree Fruits Cooperative

2 Simply soil..

3 Tree Fruit Replant/Decline Replant disease = fruit trees that do not establish well or fail to establish when planted on a site previously grown with tree fruits Tree fruit decline = fruit trees establish well then growth & production gradually decline within 3-5 years of planting on new ground (or previously planted) Same disease just different timing Replant/decline is not a specific disease caused by a single agent, but rather a complex of biotic and abiotic stressors

4 Tree Fruit Replant/Decline Contributing factors to replant/decline Complex of fungal pathogens incl. Cylindrocarpon, Fusarium, Rhizoctonia, Pythium, Phytopthora,?? Mycorrhizal fungi (specific pathogen mix varies with site) Plant pathogenic nematodes Soil abiotic factors (i.e. ph,nutrient status, soil texture) It is important to know your soil for replant establishment and maintained health of established trees Aid decision making soil treatments (i.e. fumigation), rootstocks, amendments Stressed trees are more susceptible to diseases such as Cytospora and bacterial canker

5 Why does Tree Fruit Replant /Decline occur? Planting a young traumatised tree with an immature root system into this 'broth' of pathogens can be too much for an infant tree Any new root growth is rapidly and heavily colonized so that shoot growth is virtually zero Disease severity is greater on sites previously planted with large standard trees (pathogens survive in dead wood and organic matter) Amplified on dwarfing rootstock which by its nature will be relatively inefficient

6 Replant/Decline management Prevention is much easier and more successful than control. There is very little that can be done to correct replant problems once the trees are planted. Not all soils respond in the same way to the various pre-plant treatments Pre-plant soil testing can help to identify potential causes of poor replant performance and is highly encouraged (e.g. soil fertility testing, plant pathogenic nematode testing, replant pot test) Know your soil and site!!!!

7 Replant Orchard Analysis

8 Root weight (g) Replant Orchard Analysis Soil fertility analysis, plant pathogenic nematode count and pot test = Bioassay test ab a a abc abc c c c bc SOIL ANALYSIS GROWER: DATE OF SAMPLING: GROWER NUMBER: TYPE OF TEST: Basic + Boron + CEC SAMPLE AREA DETAILS: c Excessive High 1 Ideal Low 0.5 Deficient Ca (%) Mg (%) K (%) P (%) B (%) Na (%) Fe (%) Mn (%) Cu (%) Zn (%) PPM Base Saturation (meq/100g) Calcium Magnesium Potassium Sodium Phosphorus Boron Iron Manganese Copper Zinc 0 Control Peat Autoclave MAP MKP Manzate Aliette Movento Organic Matter % 3.4 ph 6.2 Total Exchange Capacity 16.1 (CEC) Total Nitrogen % 0.13 Electrical Conductivity (mmhos/cm 0.46 (soil saline if >1.5)

9 Soil fertility analysis

10 Plant Pathogenic Nematode Testing Nematode Extraction Procedures: Baermann Pan Method extraction of root lesion and free-living nematodes Sucrose extraction for ring nematodes Nematodes of concern in local tree fruit orchards: Root lesion nematode (Pratylenchus sp.) Ring nematode (Mesocriconema sp.) Pin nematode (Paratylenchus sp.) Dagger nematode (Xiphenema sp.)

11 Plant Pathogenic Nematode Testing Nematode Genera Root lesion nematode (Pratylenchus sp.) Guideline thresholds 100 per 100 cc soil, 50 per 1 g root Root knot nematode (Meloidogyne sp.) 100 per 100 cc soil Pin nematode (Paratylenchus sp.) 100 per 100 cc soil Dagger nematode (Xiphinema sp.) 50 per 100 cc soil Stem and bulb nematode (Ditylenchus sp.) 100 per 100 cc soil (not likely cause of tree fruit decline)

12 Replant pot test Examines the effects of soil treatments on the growth of apple seedlings grown for 10 weeks in the replant soil Treatments include untreated control, fumigation, compost (Glengrow), peat, various forms of phosporous ( , , ), etc. Soil treatments are altered based on the soil fertility results Results shoot height & weight, root weight and the weight of 5 leaves

13 Shoot height (cm) Replant pot test 25 a 20 a a a ab 15 bc bc 10 c c c 5 0 Control Peat Autoclave MAP MKP Manzate Aliette Movento

14 Root weight (g) Replant pot test

15 Replant Advising Services (RAS) pilot program - collaborative effort between BC Ministry of Agriculture, BCTF and Summerland Varieties Corporation to maximize the success of the replant program streamline/coordination of planning and implementation of replant plans with subsequent follow-up

16 Replant Advising Services (RAS) If you are interested in the horticultural advising service please contact: Danielle Hirkala at or If you are a cooperative grower and have already been in touch with your field person proceed through them

17 Replant Orchard Analysis / Bioassay Test & Replant Advisory Service (RAS) Dr. Danielle Hirkala BC Tree Fruits Cooperative