Fruit and soil quality of organic and conventional strawberry agroecosystems.
BACKGROUND
Sale of organic foods is one of the fastest growing market segments within the global food industry. People often buy organic food because they believe organic farms produce more nutritious and better tasting food from healthier soils. Here we tested if there are significant differences in fruit and soil quality from 13 pairs of commercial organic and conventional strawberry agroecosystems in California.


RESULTS
At multiple sampling times for two years, we evaluated three varieties of strawberries for mineral elements, shelf life, phytochemical composition, and organoleptic properties. We also analyzed traditional soil properties and soil DNA using microarray technology. We found that the organic farms had strawberries with longer shelf life, greater dry matter, and higher antioxidant activity and concentrations of ascorbic acid and phenolic compounds, but lower concentrations of phosphorus and potassium. In one variety, sensory panels judged organic strawberries to be sweeter and have better flavor, overall acceptance, and appearance than their conventional counterparts. We also found the organically farmed soils to have more total carbon and nitrogen, greater microbial biomass and activity, and higher concentrations of micronutrients. Organically farmed soils also exhibited greater numbers of endemic genes and greater functional gene abundance and diversity for several biogeochemical processes, such as nitrogen fixation and pesticide degradation.


CONCLUSIONS
Our findings show that the organic strawberry farms produced higher quality fruit and that their higher quality soils may have greater microbial functional capability and resilience to stress. These findings justify additional investigations aimed at detecting and quantifying such effects and their interactions.
Reganold
John P
JP
Department of Crop and Soil Sciences, Washington State University, Pullman, Washington, United States of America. reganold@wsu.edu
Andrews
Preston K
PK
Reeve
Jennifer R
JR
Carpenter-Boggs
Lynne
L
Schadt
Christopher W
CW
Alldredge
J Richard
JR
Ross
Carolyn F
CF
Davies
Neal M
NM
Zhou
Jizhong
J
D000383:Agriculture / Q000379:methods*; D002244:Carbon / Q000032:analysis; D031985:Fragaria / Q000737:chemistry* / Q000235:genetics / Q000254:growth & development; D005638:Fruit / Q000737:chemistry / Q000254:growth & development; D009584:Nitrogen / Q000032:analysis; D058871:Organic Agriculture; D010936:Plant Extracts / Q000032:analysis; D012987:Soil / Q000032:analysis*
D010936:Plant Extracts; D012987:Soil; D002244:Carbon; D009584:Nitrogen
ISME J. 2007 May;1(1):67-77
18043615
Appl Environ Microbiol. 2001 Jul;67(7):3245-57
11425748
Appl Environ Microbiol. 2004 Jul;70(7):4303-17
15240314
J Pharm Biomed Anal. 2005 Sep 1;39(1-2):164-9
16085136
Planta. 1983 Apr;157(3):239-44
24264153
Appl Environ Microbiol. 1998 Aug;64(8):2814-21
9687435
Proc Natl Acad Sci U S A. 2008 Jun 3;105(22):7768-73
18509054
Am J Clin Nutr. 2009 Sep;90(3):680-5
19640946
J Altern Complement Med. 2001 Apr;7(2):161-73
11327522
Science. 1993 Apr 16;260(5106):344-9
17838252
Nature. 2001 Apr 19;410(6831):926-30
11309616
Trends Ecol Evol. 2006 Jun;21(6):288-95
16769427
Am J Clin Nutr. 2005 Jan;81(1 Suppl):268S-276S
15640490
Science. 2002 May 31;296(5573):1694-7
12040197
Appl Environ Microbiol. 2006 Jul;72(7):4931-41
16820490
Science. 2001 Oct 26;294(5543):804-8
11679658
J Sci Food Agric. 1972 Apr;23(4):465-73
5029975
Crit Rev Food Sci Nutr. 2002 Jan;42(1):1-34
11833635
Environ Health Perspect. 2003 Mar;111(3):377-82
12611667
Proc Nutr Soc. 2002 Feb;61(1):19-24
12002790
J Chromatogr B Analyt Technol Biomed Life Sci. 2009 Aug 1;877(23):2235-43
19577965
Food Addit Contam. 2002 May;19(5):427-46
12028642
ISME J. 2010 Sep;4(9):1099-107
20376100
J Agric Food Chem. 2006 Feb 22;54(4):1248-55
16478244
J Pharm Biomed Anal. 2005 Aug 10;38(5):798-805
16076542
Int J Food Sci Nutr. 2003 Sep;54(5):357-71
12907407
Am J Clin Nutr. 2005 Jan;81(1 Suppl):215S-217S
15640483
Physiol Plant. 2004 Apr;120(4):519-528
15032813
Appl Environ Microbiol. 1996 Feb;62(2):316-22
8593035
Am J Clin Nutr. 2005 Oct;82(4):721-32
16210699
J Agric Food Chem. 2005 Nov 30;53(24):9536-43
16302774
Environ Health Perspect. 2006 Feb;114(2):260-3
16451864