Opuntia stricta (Pest pear of Australia, Suurturksvy)

Opuntia stricta (Pest pear of Australia, Suurturksvy)

[=Opuntia macrantha]

Life > eukaryotes > Archaeoplastida > Chloroplastida > Charophyta > Streptophytina > Plantae (land plants) > Tracheophyta (vascular plants) > Euphyllophyta > Lignophyta (woody plants) > Spermatophyta (seed plants) > Angiospermae (flowering plants) > Core Eudicots > Order: Caryophyllales > Familty: Cactaceae > Genus: Opuntia

Native from the southern USA to Venezuela. A declared Category 1 invasive plant in South Africa.

Cactoblastis cactorum (Lepidoptera: Pyralidae: Phycitinae). The orange and black striped larvae of this moth eat the parenchymous tissue inside the cladodes of a wide variety of Opuntia species, including Opuntia stricta. It was released in South Africa in 1933 for the biological control of Opuntia ficus-indica. Cactoblastis cactorum is world famous as a biological control agent of Opuntia stricta in Australia, and while it has caused extensive damage to Opuntia stricta infestations in South Africa (Klein 2011), the damage has not been as great as in Australia.
Dactylopius opuntiae (Hemiptera: Dactylopiidae). The 'stricta' biotype was released in 1997 against Opuntia stricta and has caused extensive damage. Dactylopius species are collectively known as cochineal insects and are all characterised by having vivid red body contents that from Dactylopius coccus is used for producing cochineal dye. The females suck the juices from the cactus and those of Dactylopius opuntiae are easily noticed on the plant because of their untidy covering of waxy filaments, looking rather like blobs of cotton wool.

Klein H. 2011. A catalogue of the insects, mites and pathogens that have been used or rejected, or are under consideration, for the biological control of invasive alien plants in South Africa. African Entomology 19(2): 515-549.

Text by Hamish Robertson