Inert Dusts

Factors affecting the insecticidal efficacy of the diatomaceous earth formulation SilicoSec® against adults of the rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae)

“…The reports on the influence of rh on DE efficacy are in agreement with the fact that DE formulations are not effective at high rh levels, and this trend is evident for all beetle species examined so far (Le Patourel, 1986;Aldryhim, 1990Aldryhim, , 1993Arthur, 2000;Fields and Korunic, 2000;Vayias and Athanassiou, 2004). Low rh values cause a more rapid desiccation, which is the mode of action of DE (Subramanyam and Roesli, 2000). According to our results, a change in rh level does not always have the same effect in the insecticidal efficacy of SilicoSec ® against S. oryzae.…”

“…DE formulations are created by the fossils of diatoms and they are composed of amorphous hydrated silica. DE particles damage the cuticle, resulting in water loss and death through desiccation (Korunic, 1998;Fields and Korunic, 2000;Subramanyam and Roesli, 2000;Mewis and Ulrichs, 2001). These dusts are of natural origin with low mammalian toxicity and can be easily removed from the grain during processing and milling (Korunic et al, 1996;Subramanyam and Roesli, 2000).…”

“…DE particles damage the cuticle, resulting in water loss and death through desiccation (Korunic, 1998;Fields and Korunic, 2000;Subramanyam and Roesli, 2000;Mewis and Ulrichs, 2001). These dusts are of natural origin with low mammalian toxicity and can be easily removed from the grain during processing and milling (Korunic et al, 1996;Subramanyam and Roesli, 2000). DE formulations are usually applied directly to the product with almost the same technology as traditional residual insecticides (Subramanyam and Roesli, 2000), so there is practically no need for expensive changes in application machinery in stored-grain facilities.…”

“…These dusts are of natural origin with low mammalian toxicity and can be easily removed from the grain during processing and milling (Korunic et al, 1996;Subramanyam and Roesli, 2000). DE formulations are usually applied directly to the product with almost the same technology as traditional residual insecticides (Subramanyam and Roesli, 2000), so there is practically no need for expensive changes in application machinery in stored-grain facilities. Several studies have shown that DE formulations are effective against a wide range of species, but researchers underline the fact that DE efficacy can be affected by several biotic or abiotic factors; e.g., temperature (Aldryhim, 1990(Aldryhim, , 1993Arthur, 2000Arthur, , 2002Fields and Korunic, 2000;Athanassiou et al, 2005), moisture content or relative humidity (Arthur, 2000(Arthur, , 2002Fields and Korunic, 2000;Vayias and Athanassiou, 2004), and type of product (Athanassiou et al, 2003).…”

Resfriamento artificial para o controle de Coleoptera em arroz armazenado em silo metálico

“…O efeito da temperatura sobre o desenvolvimento e reprodução dos insetos tem sido estudado e revisado por Howe (1965), Fields (1992), Prakash & Rao (1995) e Subramanyam & Roesli (2000). Segundo Fields (1992), a temperatura ótima para o desenvolvimento da maioria das espécies de insetos de produtos armazenados situa-se em torno de 25-33 o C. A utilização da temperatura, tanto o aquecimento da massa de grãos a 55-65 o C quanto o resfriamento a 14-16 o C ou abaixo, representa uma estratégia para reduzir o desenvolvimento desses insetos, contudo, a temperatura aplicada não pode causar efeitos adversos na qualidade dos produtos.…”