Insects - wheat

Contributors to this page: CIMMYT, Mexico (Etienne Duveiller, Monica Mezzalama, Eloise Phipps, Thomas Payne, Jesper Norgaard), Independent consultant (Jesse Dubin).

Khapra beetle

Scientific name

Trogoderma granarium Everts

Importance

High phytosanitary importance.

Significance

The khapra beetle is considered to be one of the world's most destructive pests of grain products and seeds. It is principally serious under hot dry conditions. Reproduction may be so rapid that larvae are found in large numbers in the surface layers of binned grain. The discovery of T. granarium in a non-infested area usually leads to an immediate quarantine of suspected goods and an expensive eradication and control effort.

Symptoms

Presence in stored grain. The stage most commonly seen during inspection is the larva, and the most usual evidence for infestation is cast larval skins.

Hosts

Grain and stored product hosts.
The beetle is by nature an omnivorous protein scavenger and has been found in many locations that would not be obvious food sources.

Geographic distribution

T. granarium probably originated in the region now including Bangladesh and India. It has since spread to other areas including northern and eastern Africa, southern Europe and the Mediterranean region, and the Middle East.

EPPO distribution map: http://www.eppo.org/QUARANTINE/insects.

Biology and transmission

T. granarium is a member of the Coleoptera family Dermestidae.

The eggs are milky white, turning pale yellowish with age, cylindrical, 0.7 by 0.25 mm, with one end rounded, the other pointed and bearing spine-like projections.

The larvae at hatching are approximately 1.6 to 1.8 mm long, more than half of this length consisting of a tail made up of hairs on the last abdominal segment. Larvae are uniformly yellowish white, except the head and body hairs, which are brown. As the larvae increase in size, their body color changes to a golden or reddish brown, more body hairs develop, and the tail becomes proportionally shorter. Mature larvae are approximately 6 mm long and 1.5 mm wide. Larval development may occur in four weeks, but under conditions of cooler temperatures, crowding, or poor food quality the larvae may enter diapause.

Adults are oval-shaped and brown to black in color, with indistinct lighter brown patterns on the elytra. The adult males are 1.4-2.3 mm long and 0.75-1.1 mm wide; adult females are 2.1-3.4 mm long and 1.7-1.9 mm wide. They appear densely hairy under a microscope. These hairs may trap dust, giving a dirty appearance. Adults are short-lived, persisting only for one to two weeks.

This beetle has never been observed to fly; therefore, its spread is probably dependent on movement of infested goods or in containers where it may be transported while in diapause.

Detection/indexing methods

• At CIMMYT: Physical inspection of seed.
• At ICARDA: Visual inspection

Treatment/control

• Fumigation using methyl bromide is the treatment of choice. Because of the khapra beetle's habit of hiding in cracks and crevices and infesting porous block, the entire storage structure, in addition to its contents, must be fumigated. The future for the continued use of methyl bromide fumigation for khapra beetle is currently uncertain.

Procedures followed at the centers in case of positive test

• At CIMMYT: The seed lot is destroyed (the pest is quarantined in Mexico).
• At ICARDA: Double dose of fumigation with phostoxin

EPPO protocols

EPPO Diagnostic Protocols for Regulated Pests PM 7/13(1): Trogoderma granarium. EPPO Bulletin 32: 241-243. [online] Available from URL: http://www.eppo.org/QUARANTINE/insects/. Date accessed 07 April 2010

References and further reading

Banks HJ. 1977. Distribution and establishment of Trogoderma granarium Everts (Coleoptera: Dermestidae); climatic and other influences. Journal of Stored Product Research 13: 183-202.

Buss LB, Fasulo TR. 2006. UF/IFAS Photo Gallery Stored Product Pests CD-ROM SW 185. Unifersity of Florida IFAS Extension.

EPPO. Data Sheets on Qurantine Pests: Trogoderma granarium. [online] Available from URL:http://www.eppo.org/QUARANTINE/insects/. Date accessed 07 April 2010

French S, Venette RC. 2005. Mini risk assessment: khapra beetle, Trogoderma granarium (Everts) [Coleoptera: Dermestidae]. United States Department of Agriculture. [online] Available from URL: http://www.aphis.usda.gov/ Date accessed 07 April 2010

Lowe S, Browne M, Boudjelas S, DePoorter M. 2000. 100 of the World's Worst Invasive Alien Species: A Selection from the Global Invasive Species Database. Invasive Species Specialist Group, World Conservation Union (IUCN). 12 pp. [online] Available from URL: http://www.issg.org/booklet.pdf. Date accessed 07 April 2010

Szito A. (2006). Trogoderma granarium (insect). Global Invasive Species Database. [online] Available from URL: http://www.issg.org/database/ Date accessed 07 April 2010.

Von Ellenrieder N. 2004. Pest Sheet: Khapra beetle (Trogoderma granarium). Entomology Laboratory, Plant Pest Diagnostics Center, California Department of Food and Agriculture. [online] Available from URL: http://www.cdfa.ca.gov/. Date accessed 07 April 2010

ZipcodeZoo.com. 2009. Trogoderma granarium (khapra beetle). [online] Available from URL: http://zipcodezoo.com/Animals. Date accessed 07 April 2010

Weeds - wheat

Contributors to this page: CIMMYT, Mexico (Etienne Duveiller, Monica Mezzalama, Eloise Phipps, Thomas Payne, Jesper Norgaard), Independent consultant (Jesse Dubin).

Creeping thistle, Canada thistle

Scientific name

Cirsium arvense (L.) Scop.

Importance

High.

C. arvense is a noxious weed of the Asteraceae family. It is difficult to eradicate, and is usually introduced accidentally as a contaminant in cereal crop seeds. It is present in Mexico but limited to certain areas. Many countries regulate this plant, or its parts (i.e., seed) as a contaminant.

Significance

C. arvense is a serious invasive species in regions where it has been introduced. It is difficult to eradicate because it produces rhizomes.

Hosts

Cereals and other crops.

Geographic distribution

Native to Europe. Present in the USA, Canada, Mexico, Brazil, South Asia, Brazil, Australia and New Zealand.

Biology

C. arvense is a tall, herbaceous, perennial plant, forming extensive clonal colonies from an underground root system that sends up numerous erect stems each spring, reaching 1-1.2 m tall (occasionally more). The stems often lie partly flat by summer but can stay erect if supported by other vegetation. The leaves are very spiny, lobed, up to 15-20 cm long and 2-3 cm wide (smaller on the upper part of the flower stem). The inflorescence is 10-22 mm in diameter, pink-purple in color, with all the florets of similar form (i.e., with no division into disc and ray florets). The flowers are usually dioecious, but not invariably so, with some plants bearing hermaphrodite flowers. The seeds are 4-5 mm long, with a feathery pappus that assists in wind dispersal.

Most seeds germinate within a year, but buried seed can stay dormant for up to 20 years.

Detection/indexing methods used

• At CIMMYT: Physical inspection of seed
• At ICARDA: Not applicable

Treatment/control

• Killing the roots is the only effective control method in the field. A combination of spring-summer mowing and herbicide application in the fall is extremely effective. There is no seed treatment available

Procedures followed at the centers in case of positive test

• At CIMMYT: Depending on the level of infestation, the seed may be cleaned (i.e., the weed propagules are removed from the wheat seed). If the infestation rate is too high the seed lot is destroyed.
• At ICARDA: Not applicable

References and further reading

Alberta Invasive Plants Council. Invasive alien species factsheet: Canada thistle (Cirsium arvense). [online] Available from URL: http://www.invasiveplants.ab.ca/Downloads/FS-CanadaThistle.pdf. Date accessed 07 April 2010

Blamey M, Grey-Wilson C. 1989. The Illustrated Flora of Britain and Northern Europe. London: Hodder and Stoughton.

United States Department of Agriculture (USDA). PLANTS profile: Cirsium arvense (L.) Scop., Canada thistle. [online] Available from URL: http://www.plants.usda.gov/. Date accessed 07 April 2010
 

Safe transfer of lentil germplasm

Contributors to this page: ICARDA, Aleppo, Syria (Siham Asaad, Abdulrahman Moukahal).

ICARDA, as one of the 15 CGIAR centers, has the mandate for care and maintenance of lentil germplasm.
Information is included on:

• Import and export requirements. 
• Technical guidelines for the safe movement of germplasm and detection of relevant pathogens and pests. 

Import/export of lentil germplasm

Contributors to this page: ICARDA, Aleppo, Syria (Siham Asaad, Abdulrahman Moukahal).

Lentil is a crop under the mandate of ICARDA. It is very important to remember that an International Phytosanitary Certificate is always required for any plant germplasm exchange.

The requirements of countries that request and receive seed from ICARDA Headquarters located in Syria have been collected from the permits granted to ICARDA for exportation of lentil experimental seed. It indicates specific requirements and the pathogens and pest that seed should be free of when it is imported to a given country.
Please consider that:

• The information received from the same country may vary from a permit to another; therefore the latest has been considered the valid one.
•  It is always advisable before sending a shipment to contact the consignee in the recipient country to confirm the information reported in this table.