Trichogramma Wasp

Trichogramma pretiosum — a representative species in genus Trichogramma — is one of about 200 species in family Trichogrammatidae (the trichogrammatid wasps — TINY parasitoid wasps that lay eggs inside the eggs of moths and butterflies). The species is widespread across all of North and South America and is one of the most-used Trichogramma species in commercial biological control. Adults are extraordinarily TINY — 0.3-0.8 mm long, SMALLER THAN A GRAIN OF SAND. The species' diagnostic features: tiny body size, yellow-orange body coloration, large red compound eyes (proportionally large compared to the small body), and short clubbed antennae. The species' biology is unlike most Hymenoptera in TARGETING THE EGG STAGE OF HOSTS rather than larval or pupal stages. Female Trichogramma wasps locate the eggs of LEPIDOPTERAN PESTS (moth and butterfly eggs — typically 0.5-1 mm in size) on host plant leaves and lay 1-3 of their own eggs INSIDE EACH HOST EGG using a needle-like ovipositor. The wasp eggs hatch inside the host egg and the developing wasp larvae CONSUME THE HOST EGG CONTENTS from inside, KILLING THE DEVELOPING HOST LARVA before it can hatch and damage crops. The wasp larvae develop inside the host egg over 2-3 weeks, pupate, and emerge as adults by chewing through the host egg wall. The egg-parasitism strategy is one of the most-cited examples of ARTHROPOD PARASITOID BIOLOGY in modern entomology. The species is one of the MOST COMMERCIALLY MASS-REARED biological control agents in the world. Commercial Trichogramma production began in the 1920s-1930s and has expanded dramatically over the past century — BILLIONS of Trichogramma wasps per year are produced in commercial insectaries worldwide and released across hundreds of millions of hectares of agricultural land. Major commercial Trichogramma production countries include: RUSSIA (the largest Trichogramma producer worldwide — annual production reaches 100+ billion wasps released across millions of hectares of corn, sugar beet, and other crops), CHINA (major Trichogramma production for sugarcane borer and other crop pests), MEXICO (major Trichogramma production for corn earworm and sugarcane borer), and BRAZIL (Trichogramma production for sugarcane borer and other tropical crop pests). Major target pests include CORN EARWORM, EUROPEAN CORN BORER, SUGARCANE BORER, COTTON BOLLWORM, ARMYWORMS, and many other lepidopteran crop pests. The Trichogramma program is one of the foundational case studies in modern AUGMENTATIVE BIOLOGICAL CONTROL and is featured in essentially every modern textbook discussion of arthropod biocontrol. The species is harmless to humans (way too small to be noticed by humans — even when present in millions of individuals released on a single agricultural field, the wasps are essentially invisible).