Pathogens
       
  How are fungal pathogens beneficial?  
  Identify five fungal pathogens that destroy rice insect pests.  
       
Zoophthora radicans
   Disease-causing organisms or pathogens kill very few insect pests of rice. The exception, however, is the Zoophthora radicans (Brefeld) Batko. It wipes out most leaf folder larvae of irrigated rice fields in early October of the second cropping season.

  
Beauveria bassiana
  

Fungal-infected hoppers are relatively common in wetland rice fields. Hoppers infected with the fungus Beauveria bassiana (Balsamo) Vuillemin, family Moniliaceae, become white as the pathogen grows out of the host. The remains of the dead insect stick to the rice plants in the field.

The fungus Beauveria bassiana growing out of the host (left) and the remains of infected insects sticking to rice plants in the field (right).

 
Metarhizium anisopliae
   Metarhizium anisopliae (Metchnikoff) Sorokin, also a Moniliaceae, attacks beetles, hoppers, and black bugs. Infected hosts are killed as the fungus grows and "wraps" the body of the host.

Metarhizium anisopliae attacking hoppers and black bugs.

 
Nomuraea rileyi
  An equally effective fungus against rice-defoliating caterpillars is Nomuraea rileyi (Farlow) Samson, family Moniliaceae. Infected larvae are coated with thick pale green spores and can be easily seen on the rice leaves in the fields.

Infected larvae are coated with thick pale green spores.

 
Hirsutella citriformis
   Hirsutella citriformis (Speare), family Stilbaceae, is another fungus that attacks and destroys hoppers. Once inside the body of the hopper, the fungus utilizes the inner tissues of the host and gradually grows out as long, hairy, and dirty white filaments. It covers the entire body of the infected hopper.

Fungus grows out of the hopper's body as long, hairy, and dirty white filaments.

 
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