Both nymphs and adults of the insect are found either at the base or on the upper part of the plants. The earliest signs are the wilting of leaves and stunting of plants due to the feeding activities on phloem sap and the damage of tissues which result in loss of water and nutrients. High population densities can lead to “hopperburn”, i.e leaves progressively turn orange-yellow from the tip to the mid vein, then dry up and die. Plants are stunted, develop fewer tillers and may lodge. Insects can also attack panicles, resulting in brown ears, rusty or black-cracked kernels, and reduced grain production.
The damage is caused by the whitebacked planthopper, Sogatella furcifera. Adults are about 3 mm long, light brown to black, and have translucent forewings with a characteristic dark brown mark at the tip. This insect attacks preferably high yielding varieties. Its high reproductive potential and its migratory habits makes it a major pest of rice in East-Asia and Australia. It also transmits viruses in a persistent manner, for example the rice black streaked dwarf virus and the southern rice black-streaked dwarf virus. Planting time, the excessive use of nitrogen and the availability of water for irrigation affect the populations significantly. Environmental factors such as temperature, humidity or rainfall are also key drivers in its life cycle.
Naturally-occurring biological control agents can normally keep populations of S. furcifera low. Predators include the mirid bug Cyrtorhinus lividipennis and some fairyflies of the genus Anagrus (A. flaveolus, A. perforator, A optabilis and A. frequens) that attack the eggs of the pest. There are also a number of predatory spiders that attack this pest, for example Lycosa pseudoannulata. Finally, the fungal pathogen Erynia delphacis can also help to reduce populations of the pest.
Always consider an integrated approach with both preventive measures and biological treatments if available. Insecticides have been used heavily for management, which has resulted in the development of resistance. Oxamyl, some pyrethroids, buprofezin and pymetrozin should be alternated for an effective treatment.