[Edited_by_A._Ciancio,_C.N.R.,_Bari,_Italy_and_K.(Bookos.org)

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death of the mite through the cuticle and forms new spores. It takes about 4 h for a spore to
penetrate the cuticle of the host, while time from infection to formation of new spores is
around 4 days at 25–30°C (Fig. 4).
The fungus can easily be grown on artificial media and this property together with its
high infective potential towards the citrus rust mite (CRM) has led to research aimed at the
development of the fungus as biological control agent. Large-scale laboratory and industrial
production methods have been developed for the production of mycelial and conidial
preparations (McCoy, Hills, & Kanavel, 1975; McCoy, 1981). It was planned to introduce
the fungus early in the season as a prophylactic to reduce outbreaks of the CRM.
Commercial production of conidial preparation in the USA was developed in 1975–1976
by Abbott Laboratories and full registration was received for a mycoacaricide for the
control of eriophyids on citrus under the name Mycar TM . Several hundreds of kilograms
were sold of the product but commercial production was discontinued in 1985 as too many
factors affected the stability and reliability of the acaricide.
Interest in the production of H. thompsonii based acaricides for use against eriophyids
continued in other countries even after the production of Mycar TM in the USA was
discontinued. Experiments have been conducted in several countries, e.g. Brazil, Argentina,
Mexico and Sri Lanka, but these studies have yet not led to a commercial biological control
product. More successful were studies in India where the coconut mite, Aceria (Eriophyes)
guerreronis, is a major constraint to coconut farming in India, the third largest producer of
coconuts in the world. Biological control has been considered for a long time, despite the
availability of other control methods, including chemical and botanical pesticides and
nutrition-based cultural methods (Sreerama Kumar & Singh, 2001; Sreerama Kumar,
2006). Research has resulted in the identification of the most infective mite pathogen,
H. thompsonii, as important regulator of the coconut mite (Fig. 5). Further research had led
to the production of a biological acaricide, Mycohit TM , with a mixture of mycelium
Figure 5. Aceria (Eriophyes) guerreronis infected by Hirsutella thompsonii.
Photograph courtesy of Dr. P. Sreerama Kumar.