Soil quality and cover crops in red raspberry in the Pacific Northwest
Rachel Rudolph, Inga Zasada, and Lisa DeVetter
Small Fruit ConferenceDecember 1, 2016
Introduction
• Red raspberry is a valuable crop to Washington
• Total acreage has increased in the Pacific Northwest (PNW), but crop longevity has decreased
• The decline is attributed to various factorshttp://www.raspberries.us/
Soil management challenges
• Pathogenic fungi• Pathogenic bacteria• Plant parasitic nematodes• Improper pH• Soil nutrient deficiency
Soil management challengesPratylenchus penetrans, or root lesion nematode (RLN), is one of the most important raspberry pests
• Non-segmented roundworm • Migratory endoparasite • Feeds on roots, causes reduced
uptake of water and nutrients• Dark lesions develop on roots• Plants can decline rapidly
http://extension.oregonstate.edu/umatilla/pests/rootlesionnematodes
Current management practices• Alleyways are commonly kept clean by repeated
rototilling/cultivation and herbicides• Alleyway cover cropping is not a common practice
in PNW red raspberry systems• Repeated cultivation can:
• Increase soil erosion • Increase compaction • Contribute to loss of soil physical structure • Reduce nutrient and water holding capacity• Increase dust during the dry season
Potential benefits of cover crops
• Increased soil organic matter • Weed suppression • Soil structure improvement • Pest and pathogen suppression • Promotion of beneficial soil microorganisms • Improved nutrient cycling/management• Increased water infiltration
Keep in mind…• Proper selection of cover crops is crucial
because many cover crop species may serve as hosts for P. penetrans
• White clover • Barley • Oat • Cereal rye
Photos by Brigid Meints
Field experiment: Cover crops and ground covers in established red raspberry alleyways
Objectives• Measure the effects of alleyway cover cropping in established red
raspberry on:• Soil quality—physical, chemical, biological• P. penetrans population dynamics• Soil microbial community structure• Plant competition
• Evaluate suitability of annual and perennial cover crops in PNW red raspberry production system.
http://www.almanac.com/plant/raspberries
Experimental design• Fall 2014-Fall 2016• Established commercial ‘Meeker’ red
raspberry field• History of RLN, but no root rot• CRD, 9 treatments, 4 reps, untreated
cultivated bare soil and weedy mown plots served as controls
• Treatment plots were 30 ft x 12 ft and spanned the entire alleyway on both sides of the row and a minimum of 60 ft were maintained between plots as buffer
• Treatments seeded twice over two years (once each fall)
Treatments• W1: Hard, red winter wheat cv. Norwest 553 (Triticum aestivum)• W2: Soft, white winter wheat cv. Rosalyn (T. aestivum)• O1: Winter-hardy oats cv. TAM 606 (Avena sativa)• O2: Winter-hardy oats cv. Nora (A. sativa)• G1: *Ryegrass (Lolium spp.) mix that included 51.25% intermediate ryegrass cv.
Tetralite and 48.24% tetraploid perennial ryegrass cv. Kentaur • G2: Perennial ryegrass (L. perenne) mix that included 43.93% ‘Esquire’, 31.44%
‘TopHat 2’, and 22.49% ‘Tetragreen’• T1: Triticale cv. Trical 103BB (Triticosecale sp.)• T2: Triticale cv. TriMark 099 (Triticosecale sp.)• R: Generic cereal rye (Secale cereale)• Mow: Control, weedy mow• Till: Control, bare soil, repeatedly rototilled (common industry practice)
Data collectionVariable Fall 2014 Spring 2015 Summer 2015 Fall 2015 Spring 2016 Summer 2016 Fall 2016SoilsBulk density x x x xPenetration x x x xNutrients (macro, micro, organic matter) x x x x xSoil microbiology x x x x xNematodes in soil x x x x xRaspberry plantsYield x xBerry weight & quality x xCane density x xNematodes in roots x x x x x
Take Home Message 1
Repeated cultivation did not significantly out perform ground cover treatments in any measured soil quality parameter.
Soil quality--physicalSpring 2015 Fall 2015
Spring 2016 Fall 2016
Lower bulk density =
less compaction=
better soil quality
Soil quality--chemical
• Cation exchange capacity (CEC), pH, % organic matter, N, P, K• Few significant differences among treatments.
Soil quality—biological
• Data forthcoming
Take Home Message 2
Alleyway cover crops did not significantly affect yield or plant performance.
Summer 2015 estimated yield and fruit quality
No significant differences in fruit yield or quality among treatments
Yield Fruit quality
Summer 2016 estimated yield and fruit quality
• No significant differences in fruit yield or fruit quality among treatments in 2016
• Fruit quality in all treatments was significantly higher than 2015
Yield Fruit quality
Take Home Message 3
Alleyway cover crops are maintenance hosts for P. penetrans, but vary in host suitability.
P. penetrans densities in alleyway soil
• P. penetrans population densities in soil were low in both years.• Till did not have significantly lower densities than many other treatments
in both years.
Spring 2015 and 2016 Fall 2015 and 2016
P. penetrans densities in bed soil
Spring 2015 and 2016 Fall 2015 and 2016
Average P. penetrans densities in bed vs. alley
Pp/100 g of soilBed Alleyway
Spring 2015 99 18Fall 2015 184 10Spring 2016 129 10Fall 2016 129 28
Take Home Message 4
Alleyway cover crops do not impact P. penetrans population densities in the raspberry crop.
P. penetrans densities in raspberry roots
Spring 2015 and 2016 Fall 2015 and 2016
P. penetrans populations were lower in most treatments in both the spring and fall in 2016.
P. penetrans densities in raspberry roots over time
Till
G2W2
G1Mow
Conclusions• Alleyway cover crops do not negatively affect raspberry yield or fruit
quality compared to bare soil alleyways.• Alleyway P. penetrans populations do not affect bed P. penetrans
populations.• Raspberry planted in plots with bare soil did not fare better than
raspberry planted in plots with cover crops under any measured parameter.
• P. penetrans population densities did not increase over time in raspberry roots.
• Cover crops were hosts for P. penetrans, but some were less suitable than others.
Alleyway cover crops: Pros vs. Cons• Pros:
• Lower bulk density when left to grow over time• Easier management with mowing compared to rototilling• Less expensive?• No increase in P. penetrans populations over time in raspberry
roots• No difference in yield or fruit quality compared to bare soil• Less dust/soil in the air during dry season• Less standing water in alleyways• Soil microbiological changes?
• Cons:• Cost of seed and planting• No increase in fruit yield or quality• Soil microbiological changes?
Acknowledgments
• Grower cooperator• Dr. Zasada’s lab• Dr. DeVetter’s lab• Northwest Agricultural Research Foundation• Washington Red Raspberry Commission
Literature cited• Bélair, G. 1991. Effects of preplant soil fumigation on nematode population densities, and on growth and yield of raspberry. Phytoprotect. 72(1):21-25.
• Freyman, S. 1989. Living mulch ground covers for weed control between raspberry rows. Acta Hort. 262:349-356.
• Forge, T.A., Ingham, R.E., Kaufman, D., and J.N. Pinkerton. 2000. Population growth of Pratylenchus penetrans on winter cover crops grown in the Pacific Northwest. J. Nematol. 32(1):42-51.
• Karlen, D.L., Mausbach, M.J., Doran, J.W., Cline, R.G., Harris, R.F., and G.E. Schuman. 1997. Soil quality: A concept, definition, and framework for evaluation (a guest editorial). Soil Sci. Soc. Am. J. 61:4-10.
• Kirkegaard, J.A, Gardner, P.A., Desmarchelier, J.M., J.F. Angus. 1993. Biofumigation--using Brassica species to control pests and diseases in horticulture and agriculture. Proc. 9th Australian Research Assembly on Brassica. p. 77-82.
• Kirkegaard, J.A. and M. Sarwar. 1998. Biofumigation potential of brassicas. I. Variation in glucosinolate profiles of diverse field-grown brassicas. Plant and Soil 201:71-89.
• Mazzola, M. and Y. Gu. 2002. Wheat genotype-specific induction of soil microbial communities suppressive to disease incited by Rhizoctonia solani Anastomosis Group (AG)-5 and AG-8. Phytopathol. 92(12):1300-1307.
• Magdoff, F. and H. Van Es. 2009. Building soils for better crops: Sustainable soil management. Waldorf, M.D.: Sustainable Agriculture Research and Education.
• McElroy, F.D. 1977. Effect of two nematode species on establishment, growth, and yield of raspberry. Plant Dis. Rptr. 61(4):277-279.
• McElroy, F.D. 1992. A plant health care program for brambles in the Pacific Northwest. J. Nematol. 24(3):457-462.
• Merwin, I.A., Byard, R., Robinson, T.L., Carpenter, S., Hoying, S.A., Iungerman, K.A., and M. Fargione. 2001. Developing an integrated program for diagnosis and control of replant problems in New York apple orchards. New York State Horticultural Society.
Literature Cited• Pacific Northwest Extension. 2007. Commercial red raspberry production in the Pacific Northwest. PNW 598.
• Savory, B.M. 1966. Specific replant diseases causing root necrosis and growth depression in perennial fruit and plantation crops. Commonwealth Agricultural Bureaux, Farnham Royal, Bucks, England.
• Sarrantonio, M. 2007. Building soil fertility and tilth with cover crops, p.16-24. In: A. Clark (ed.) Managing cover crops profitably. 3rd ed. Sustainable Agriculture Research and Education, College Park, M.D.
• Thies, J.A., A.D. Petersen, and D.K. Barnes. 1995. Host suitability of forage grasses and legumes for root-lesion nematode Pratylenchus penetrans. Crop Sci. 35:1647-1651.
• United States Department of Agriculture, National Agriculture Statistics Service. July 2014. Noncitrus fruits and nuts 2013 Summary. <http://www.usda.gov/nass/PUBS/ TODAYRPT/ ncit0714.pdf>.
• Vrain, T., R. DeYoung, J. Hall, and S. Freyman. 1996. Cover crops resistant to root-lesion nematodes in raspberry. HortScience 31(7):1195-1198.
• Walters, T.W., Pinkerton, J.N., Ekaterini, R., Zasada, I.A., Particka, M. Yoshida, H.A., and C. Ishida. 2009. Managing plant-parasitic nematodes in established red raspberry fields. HortTechnology 19(4):762-768.
• Zasada, I.A., S.L.F. Meyer, and M.J. Morra. 2009. Brassicaceous seed meals as soil amendments to suppress the plant-parasitic nematodes Pratylenchus penetrans and Meloidogyne incognita. J. Nematol. 41(3):221-227.
• Zasada, I.A., Walters, T.W., and J.N. Pinkerton. 2010. Post-plant nematicides for the control of root lesion nematode in red raspberry. HortTechnology 20(5):856-862.
• Zebarth, B.J., Freyman, S., and C.G. Kowalenko. 1993. Effect of ground covers and tillage between raspberry rows on selected soil physical and chemical parameters and crop response. Can. J. Soil Sci. 73:481-488.