Ultraviolet-Blocking Materials as a Physical Barrier to Control Insect Pests and Plant Pathogens in Protected Crops

Abstract

New types of ultraviolet (UV)-blocking materials, such as polyethylene films and nets, have been developed in recent years as a very promising tool to control insect vectors of plant disease threatening greenhouse crops. UV-blocking materials have properties to filter the UV radiation (280-400 nm) interfering with the vision of insects and in consequence, their behaviour related with movement, host location ability and their population parameters. The exclusion of part of the UV radiation within the greenhouse environment has a dramatically incidence on insect orientation, movement and on the spread of insect-transmitted viral diseases. In the same way, the impact of UV-absorbing materials on population dynamics of natural enemies, pollinators and crop yield needs further investigation. The level of protection of the different UV-blocking materials may vary among different designs of greenhouses and the geographic location that determines different internal climatic conditions and the amount of UV and visible light absorbed and transmitted within the covered structures. In this review, we will discuss the current knowledge about the impact of UV-absorbing films on insect pests, plant pathogens and beneficial organisms, with special attention to insects acting as vectors of plant disease. Also, the new perspectives, limitations and advantages of using UV-blocking materials together with other control strategies under Integrated Pest Management (IPM) production systems will be discussed.