Do You Want Nematodes with Your Fries?

potate

Nematode-Damaged Potato

Farmers in Oregon and Washington grow 12 billion pounds of potatoes every year. 90% of this production is for processing into potato chips and fries. 80-90% of the potato acres in Oregon and Washington are fumigated every year to reduce populations of nematodes which are microscopic parasitic worm-like animals that live in the soil and penetrate potatoes underground. Females feed just under the potato skin and deposit 200 to 1000 eggs. Brown spots become evident when the eggs are laid. Growers fumigate the soil to reduce the nematode populations because of the potential for rejection of the potatoes for processing into consumer products.

Columbia root-knot nematode (CRN) infects and develops in potato tubers but does not cause yield loss. Columbia root-knot nematode causes quality defects such as galling on the surface and small brown spots surrounding adult females when peeled. The external and internal defects render tubers unacceptable for fresh market sales and internal defects are unacceptable for processing. For processed potatoes, if between 5% and 15% of the tubers in a field have visual defects the whole-field crop can be substantially devalued or rejected. Based on USDA 2010 yields and prices, the average gross value of potatoes in Idaho was $6,921/ha. The rejection of a potato crop grown on an average 52.6-ha center-pivot-sprinkler-irrigated field represents a loss of $364,000. The potential for dire financial consequences from the presence of CRN in potato tubers is taken very seriously by producers.

Because potential for crop rejection exists with low population levels at planting, fields with any CRN must be treated with a preplant fumigant, nonfumigant nematicides, or both.”

Authors: King, B. A., and J. P. Taberna, Jr.
Affiliation: USDA, Agricultural Research Service, Kimberly, ID
Title: Site-Specific Management of Meloidogyne chitwoodi in Idaho Potatoes Using 1,3-Dichloropropene; Approach, Experiences, and Economics
Source: Journal of Nematology. 2013. 45[3]:202-213.

Advertisements

North American Ginseng Production Depends on Fumigation

Roots of American ginseng are common ingredients in herbal medicines. However, being a root crop subjects ginseng to attacks by soil-dwelling organisms, which cause root rot of ginseng seedlings. In order to prevent damage to the roots, growers typically fumigate fields before the ginseng crop is planted.

“An important component of many traditional Asian herbal medicines is dried root of American ginseng (Panax quinquefolius L.). … Although indigenous to the forests of eastern North America, most of the world supply of dried root is now provided by crops grown in cultivated fields under artificial shade structures. Over two-thirds of Canada’s ginseng crop is grown in the sandy soils of southwestern Ontario.”

“Current production methods provide environments favourable to disease development, and crop loss due to disease is significant. Although ginseng germplasm is diverse, disease-resistant cultivars are not available. … To reduce risk of damage from soilborne species of Pythium and nematodes, ginseng growers normally fumigate fields prior to seeding.” 

Authors: R.D. Reeleder¹, J. Miller¹, B. Capell¹ and J. Schooley²
Affiliation: ¹Agriculture and Agri-Food Canada, Ontario, Canada; ²Ontario Ministry of Agriculture, Ontario, Canada.
Title: Mefenoxan sensitivity and the impact of fumigation on Pythium species and Phytophthora cactorum in ginseng soils.
Publication: Canadian Journal of Plant Pathology. (2007) 29:427-436.

Chinese Ginger Relies on Soil Fumigation

Ginger, a root crop, is exposed to attack by soil-borne pathogens, nematodes, insects and weed competition. Chinese farmers produce 300,000 tons (FAO) of this important worldwide spice annually from fields that are fumigated prior to planting. A recent experiment showed that the fumigation with methyl bromide doubled ginger yields…

“Ginger weight per category and total weight were significantly affected by the fumigation programs. In the experiment, the highest yield of extra-large fruit (8.6 t/ha) was obtained in the MeBr treatment, while the lowest was achieved in the non-treated control (3.5 t/ha). … A similar trend was observed for total marketable fruit yield, where the highest yield (76.4 t/ha) was produced in the MeBr treatment plots; [while the lowest yield (48.2 t/ha) was achieved in the control plots].”

Authors: Kang Qiao, Yukun Zhu†, Hongyan Wang, Xiaoxue Ji*, Kaiyun Wang†
Affiliation: †Shandong Agricultural University, ‡Shangdong Academy of Agricultural Sciences, *Plant Protection and Inspection Station of Feicheng
Title: Effects of 1,3-dichloropropene as a methyl bromide alternative for management of nematode, soil-borne disease, and weed in ginger (Zingiber officinale) crops in China.
Publication: Crop Protection (2012) 32:71-75.