APLICAÇÃO DE REPELENTES ALTERNATIVOS EM INSETOS PRESENTES NAS SEMENTES DO MILHO ARMAZENADO EM ESPIGAS

Abstract

The present trial aimed at studying the use of common eucalyptus,
eucalyptus citriodora and the spraying with a 10% solution of creosol to
check its repellent effects on corn seeds from spikes picked manually and
mechanically, stored into 20 L cans of a concrete silo and covered with air
opening during six months. In order to compare data, it was also observed a
treatment with phosphine. Each thirty days, three spikes were randomly
removed to registered water content; plaguing degree of insects; specific weight
and weight loss. There was a huge plaguing of Sitophilus spp and Tribolium
castaneum insects. Treatments with creosol and phosphine were more
efficient, as well as showed the greatest specific weight while the treatment
with eucalyptus common recorded the smallest specific one. The treatments
did not influence on seeds weight. Seeds water content, cropped mechanically,
presented a significant decrease (P<0.05), although that it did not happen
with the manual crop, but there was an increase on the number of insects
when temperature decreased. During this trial, it was not observed an
apparent relation among relative humidity, temperature and precipitation
when compared to the observed number of insects, besides, the crop choice
influenced on the insects plaguing of corn seeds stored in spikes.