S. Villareal and K.L. Heong, International Rice Research Institute, Los Baños, Philippines
The role of the aquatic system in rice production is often taken for granted. Besides providing the essential elements, such as water and nutrients to grow a good and healthy crop, the aquatic system is also the home of thousands of aquatic predators. These predators act like sharks or piranhas that quickly zoom on to insect pests that land or fall into the water. Invading planthopper females in the early crop stages might find themselves landing into water. If the aquatic fauna is rich, insect pests, like planthoppers that land or fall into water have little chance of survival. On the other hand, if insects land up in the water with poor aquatic fauna and devoid of predators, they have higher survival chances. One such group of predators in the rice water is the veliids and in particular Microvelia douglasi atrolineata. Here we present a video showing veliids attacking a planthopper nymph.
Other videos available
Mirid bug feeding on BPH nymphs – https://ricehoppers.net/2012/07/captured-on-video-mirid-bug-cyrtorhinus-lividipennis-feeding-on-bph-nymph/
Egg predation by mirid bug – https://ricehoppers.net/page/3/?s=captured+on+video
Because most sprayers rice farmers in Asia use have poor delivery droplet discharges, most of the insecticide active ingredients delivered roll off the crop into the water. In Thailand farmers mix insecticides with diesel and pour them directly into the water. The aquatic fauna is thus most susceptible to most insecticide applications. When insecticides are reduced, the biodiversity of the aquatic species can be easily increased five folds.
Or you can watch the video here: