Information Sheet

TM IS15002

Island sugarcane Eumetopina flavipes Muir (: )

Introduction

The island sugarcane planthopper (Figure 1) is a pest that has caused significant damage to the sugarcane crops in Papua New Guinea where it is the carrier of Ramu Stunt disease. In situations where the Ramu Stunt virus is not present, the can cause minor damage when it reaches high populations.

Figure 2: Island sugarcane planthopper eggs in the leaf midrib and surrounding discolouration.

Figure 1: Island sugarcane planthopper adults and nymphs can be detected by unrolling the leaf whorl – PNG.

Symptoms Figure 3: Pale, grassy stunted shoots seen in variety This pest lays eggs under the leaf epidermis, which causes Q85S-7102, infected with Ramu stunt – PNG. local leaf discolouration (Figure 2). The insect on its own (virus free populations) may cause plant stress, yellowing Hosts of whorl and spindle deformation, especially in susceptible varieties. If the insect transmits the causal agent of The island sugarcane planthopper attacks predominantly Ramu Stunt, then symptoms of severe stunting, trashy species that are relatives to sugarcane (Saccharum appearance, leaf stripes and mottling and stool death will officinarum) and related species (Saccharum species). be evident in the sugarcane plant (Figure 3).

sugarresearch.com.au Information Sheet

TM IS15002

Distribution

While the island sugarcane planthopper has not been recorded in commercial sugarcane crops in Australia, it is present in northern parts of Australia including the Torres Strait Islands and northern tip of Cape York, and neighbouring countries including Papua New Guinea and Indonesia. The population of island sugarcane planthopper on the Torres Stait islands and Cape York does not seem to harbour the virus causing Ramu Stunt disease.

Yield loss

Virus free populations of the island sugarcane planthopper are unlikely to have any significant economic impact on sugarcane crops, unless under heavy infestations, which may lead to plant stress.

Where the insect is carrying the causal agent of Ramu Stunt disease, the economic impact will depend on the resistance level of the variety. Infected stools of susceptible varieties show severe stunting and eventually die. Root systems are also stunted and eventually die as the disease progresses. Ratoon failure is common in susceptible varieties.

Ramu stunt almost destroyed the sugarcane industry in 1986 in Papua New Guinea where a 60% reduction in productivity was recorded in one highly susceptible variety that made up 90% of the plantation (see photos on the right).

Control

While no research has been undertaken on chemicals that will effectively control island sugarcane , it is possible that pyrethroids and neonicotinoid-based insecticides, which are used against sugarcane moth borers, may be used as a means of control.

The most important and effective method of control is to limit movement of infested plant material. Preventing the movement of infested sugarcane from the Torres Strait, Cape York and neighbouring countries into commercial sugarcane areas is the first line of defense.

sugarresearch.com.au

Copyright © 2015 • All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior permission of SRA.Disclaimer In this disclaimer a reference to ‘we’, ‘us’ or ‘our’ means SRA and our directors, officers, agents and employees. Although we do our best to present information that is correct and accurate, we make no warranties, guarantees or representations about the suitability, reliability, currency or accuracy of the information we present in this Information Sheet, for any purposes. Subject to any terms implied by law and which cannot be excluded, we accept no responsibility for any loss, damage, cost or expense incurred by you as a result of the use of, or reliance on, any materials and information appearing in this Information Sheet. You, the user, accept sole responsibility and risk associated with the use and results of the information appearing in this Information Sheet, and you agree that we will not be liable for any loss or damage whatsoever (including through negligence) arising out of, or in connection with the use of this Information Sheet. We recommend that you contact our staff before acting on any information provided in this Information Sheet.Warning Our tests, inspections and recommendations should not be relied on without further, independent inquiries. They may not be accurate, complete or applicable for your particular needs for many reasons, including (for example) SRA being unaware of other matters relevant to individual crops, the analysis of unrepresentative samples or the influence of environmental, managerial or other factors on production.