They have a relatively large geographical distribution and are a known pest of many agricultural “cash” crops such as cocoa, cashew, and tea.
Thus, their impact on humans has caused them to be of great interest biologically, resulting in significant environmental implications.
Helopeltis antonii are found in a region known as the old-world tropics which encompasses places such as India, Northern Australia, Guinea, Vietnam, Tanzania, Nigeria, and Indonesia.
[2] In India their distribution is primarily found within the “cashew belt” which is located along the western coast and central regions of the country due to its high affinity for these plants.
[3] Mating typically occur in shaded, covered areas[3] Arousal consists of both chemical and tactile stimuli.
[5] Females probe plant tissues with the tip of their rostrum to find a suitable site for the deposition of their eggs.
[3] The exact reason behind site choice is unknown, but once found the female bends her abdomen to establish contact between her ovipositor and the plant tissue.
[4] H. antonii experiences partial metamorphosis, otherwise known as hemimetabolous development, which is characterized by it transition from an egg to nymph and eventually into a matured adult.
In contrast, the more matured fourth and fifth instars tend to be more dispersed and feed in areas farther from their hatch site as a result.
[4] A brownish-black colour morph is also seen within the population, but its abundance is low, and its frequency remains constant throughout the year.
Rather, both adult and nymphs feed on various sites ranging from tender shoots, buds, stems, and even their fruiting bodies to obtain sap.
[8] H. antonii possess modified mouthparts which work to form a long straw-like structure known as a “stylet”.
[7] This modified mouth part enables them to suck up sap from deep within the plant tissues that would not otherwise be as easily accessible.
As host plants enter their fruiting or flushing stages, they begin to have a higher rates of sap production and as a result become targeted by H.
[8] In native, non-cultivated, habitats there appears to be a preference for certain types of host plants even when many others are present.
[2] However, their feeding schedule on these is agricultural crops are more restricted based due to growing and harvest seasons.
However, the biochemical understanding of the toxin's toxicology and function within the saliva is poorly understood and is a site of current research.
The use of insecticides and pesticides have long been used in an attempt to manage and reduce the damaging effects of H. antonii feeding.
[11] Thus, natural predators and parasitoids have been looked to for their biological control properties to prevent the use of these harmful chemicals.
[10] Parasitoids of both nymph and adult morphs include Hymenoptera (Braconidae, Platygastridae) and Diptera (Sarcophagidae).
[10] Predators are more extensive in diversity and consist of Hymenoptera (Formicidae, Vespidae), Coleoptera, Mantodea, and Odonata.
The employment of these parasitoid specialists has significantly decreased the abundance of H. antonii eggs to effectively reduce their devastating impact on agricultural crops.
[11] The combined use of pesticides and biological control agents are less effective in reducing the number of H. antonii within agricultural systems.
[10] Biological predators and parasitoids are more affected than H. antonii due to their increase locomotory abilities causing them to be exposed to larger amounts of the synthetic pesticides found on crops.
[9] Die-back from blight also limits the plant's ability to produce products and grow—further perpetuating yield loss.