Pacific Pests & Pathogens - Mini Fact Sheet EditionAmaranthus stem weevil (351)
Pacific Pests & Pathogens - Mini Fact Sheet EditionAmaranthus stem weevil (351)
Summary
- Restricted distribution. Asia, Africa, Central America, Oceania. In Fiji. A weevil on Amaranthus species, both vegetables and weeds. Commonly called 'pigweeds'.
- Important pest. Damage by grubs (larvae) boring stems and branches. They spread Fusarium species causing decay and cankers. Pupate inside stem at base. Adults feed on leaves. Larvae spread in stems and adults on the wing.
- Natural enemies: Not reported; note, used as biocontrol of Amaranthus spinosus - major weed in Thailand.
- Cultural control: weed - especially wild amaranths; avoid adjacent overlapping crops; monitor frequently and pull out and burn wilted plants; collect and burn crop remains at harvest.
- Chemical control: PDPs (botanicals), e.g.,neem, pyrethrum and derris; or synthetic products, e.g., malathion and pyrethroids. Note, effectiveness in doubt as larvae concealed within stems/branches.
Common Name
Amaranthus stem weevil. Amaranthus weevil, pigweed weevil.
Scientific Name
Hypolixus species. The species recorded by CABI1 are Hypolixus ritsemae, Hypolixus truncatus, and Hypolixus nublilosus. Hypolixus haerens is reported as the most common pigweed weevil in Kenya.
AUTHOR Grahame Jackson
1CABI Amaranthus spinosus (spiny amaranth) (2017) Crop Protection Compendium. (www.cabi.org/cpc). Information from Tara JS (2009) Bionomics of Hypolixus truncatulus (f.) (Coleoptera: Curculionidae: Lixinae: Lixini), a major pest of Amaranthus caudatus L. Mun. Ent. Zool. Vol. 4(2); and Chittora A (2015) Insect pests of amaranthus and moringa. (https://www.slideshare.net/AkshayChittora/insect-pests-of-amaranthus-and-moringa-53613459); and Rajeshkanna et al. (2017) Biology and management of Amaranthus stem borer (Hypolixus trancatulus) Coleoptera: Curculionidae). Annals of Sri Lanka Department of Agriculture 19: 258-266; and from Blodgett J., Swart WJ, Louw SvdM (2004) Identification of fungi and fungal pathogens associated with Hypolixus haerens and decayed and cankered stems of Amaranthus hybridus. Plant Disease 88:333-337. Photos 1-5 Mani Mua, SPC, Sigatoka Research Station, Fiji.
Produced with support from the Australian Centre for International Agricultural Research under project HORT/2016/185: Responding to emerging pest and disease threats to horticulture in the Pacific islands, implemented by the University of Queensland and the Secretariat of the Pacific Community.
This mini fact sheet is a part of the app Pacific Pests and Pathogens
The mobile application is available from the Google Play Store and Apple iTunes.
Copyright © 2019. All rights reserved.