Some Like It Hot: Horseradish Needs Protection to Prevent Discoloration


Horseradish: (A) Normal; (C) Internal Discoloration

Horseradish is a root plant from the mustard family. The root is harvested in the spring and fall and is sold to processors who grate the root, releasing the oils that distinguish horseradish from all other flavors. The oil creates a hot and spicy flavor. Consumers expect horseradish to be a light color. Internal discoloration of horseradish roots is the main production problem. Internal discoloration of the root begins with dark brown to black discoloration of the vascular system and gradually spreads to the core and cortex areas in the root. Internally discolored horseradish roots are useless for industrial purposes such as preparing horseradish sauce. Research has shown that fungicides can prevent the discoloration.

“Illinois produces approximately half of the total commercial horseradish in the United States. Over the past years, horseradish growers have experienced internal discoloration in horseradish roots, causing up to 100% yield losses.  …Fungicide fludioxonil (Maxim 4FS or Maxim Potato WP) and biofungicides Trichoderma virens (G-41/ABM 127 or SoilGard 12 G) and Bacillus subtilis (Serenade MAX), applied to pathogen-free sets, protected horseradish roots against the soil-borne pathogens for approximately 12 weeks. …Application of either the fungicide or one of the biofungicides to the tissue culture-generated sets protects roots in the field through July. The remaining period of the growing season is not long enough for infection and discoloration of the roots.”

Author: Babadoost, M.
Affiliation: Department of Crop Sciences, University of Illinois, Urbana.
Title: Set treatment for controlling internal discoloration of horseradish root.
Source: Phytopathology. 2006. 96[6](Supplement):S7

Lack of Insecticides for Radishes Would Cause Significant Economic Loss in France

France is the second largest European producer, behind Germany, of radishes. Each year, France produces 48,000 tons of radishes. Damage to radishes from root maggots must be prevented in order to produce a marketable crop. But since 2007 no insecticide has been registered in France for use against root maggots. Emergency uses of unregistered insecticides have preserved the industry. A recent analysis calculated the economic costs of not having effective insecticides available.

“The additional costs caused to replace a chemical treatment by a manual operation (manual sorting at harvest) is calculated at 6,905 €/ha. At the sector level, the lack of availability of a registered plant protection product against vegetable flies would thus lead to a direct loss of 18,600,000 €. This loss in profitability seriously impacts the viability of the radish production sector in France and puts at the stake the employment directly and indirectly involved in this sector. To give an indication, in Loire-Atlantique this sector has significant weight representing 2,500 FTEs (Full Time Equivalent). … The risk of distortion of competition in the French radish production sector is real vis-à-vis other European countries where pressure of the vegetable flies is less.”

Publication: Economic damage caused by the lack of plant protection products against root maggots in radish production in France. In: Study on the Establishment of a European Fund for Minor Uses in the Field of Plant Protection Products. June 2011.
Project Leader: ARCADIA International

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.