The raspberry weevil, Aegorhinus superciliosus (Guérin) (Coleoptera: Curculionidae), is the most important pest in blueberry and raspberry fields in the south of Chile. In this study, we investigated the electroantennographic and behavioral responses of A. superciliosus to semiochemicals released from conspecific individual adults, with particular attention to male attraction to females. Odors released from females significantly attracted males in a Y-tube olfactometer. Gas chromatographic and mass spectral analysis of female volatile extracts revealed the presence of limonene and α-pinene. Electroantennogram recordings from both sexes indicated that males of A. superciliosus possess olfactory sensitivity for the R isomer of limonene and α-pinene, whereas females only perceived R-limonene. Behavioral assays using synthetic compounds showed that only R-limonene elicited an attraction response from male weevils. Field experiments confirmed the laboratory results, showing that R-limonene was attractive to weevils. This is the first report of intraspecific chemical communication in this weevil. We discuss the origin of these compounds, their possible role in the sexual behavior of this species, and their potential use in a pest control strategy.

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Food manufacturing wastes, such as olive mill solid waste, tomato pomace and grape pomace are three wastes produced by food industries in the Region of Maule. One of the simplest strategies for the proper disposal of these residues is to directly eliminate them by cultivation with degrading mesophilic microorganisms, which use these wastes as their sole carbon source. A fungal strain was isolated from tomato peel and used to degrade food manufacturing wastes. This strain was effective in degrading olive mill solid waste, but partially degraded both grape and tomato pomace. Based on mycelium morphology, sequence of part of the ribosomal and internal transcribed spacer (ITS) DNA, the strain most probably belongs to Botrytis genera. This is the first report that uses a strain similar to Botrytis in degrading food manufacturing wastes from the Region of Maule.

The effect of liquid cow manure (LCM) on dimethenamid persistence was studied using amended soils with various stabilization times and LCM doses corresponding to specific field applications. Soils were amended with LCM doses equivalent to 100,000, 200,000, and 300,000 L ha -1 . Dimethenamid (2-chloro-N-(2, 4-dimethyl-3-thienyl]-N-[2-methoxy-1-methylethyl) acetamide) was applied in a field dose. The study was conducted under controlled conditions using an Andisol without the prior application of the herbicide and LCM. Respiratory activity, fluorescein diacetate (FDA) activity, and residual dimethenamid were measured within a specific time period. The respiratory activity and FDA studies showed that LCM-amended soils were stabilized after 20 days in incubation and displayed no significant differences after applying dimethenamid. The half-life (t 1/2 ) of dimethenamid in soil was 28 days; however, in LCM-amended soils, the half-life ranged from 13 to 21 days. In the amended soil, the t 1/2 decreased significantly to 13 days in soils that contained the highest levels of LCM at 10 days of pre-incubation. The results show that both the dose and stabilization time of LCM-amended soils change the half-life of dimethenamid. Larger LCM doses are not recommended for field application. Dimethemanid should be applied 20 days after the soil amendment to increase dimethenamid efficacy.

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This work studied the sorption and mobility of dimethenamid (2-chloro-N-(2,4-dimethyl-3-thienyl)-N-(2methoxy-1-methylethyl)-acetamide) in soil amended with liquid cow manure (LCM) at doses equivalent to 0, 100, 200 and 300 thousand L ha-1 (D0, D100, D200 and D300 respectively). For the batch sorption study the amended soils were previously incubated for 30 days under controlled conditions. The mobility was evaluated under field conditions, determining the herbicide retained in different soil profiles and its concentration in soil solutions sampled with ceramic suction cups. Application of LCM at the two lowest doses (D100 and D200) did not modify dimethenamid adsorption, however adsorption increased at D300 (K foc = 62.1) as compared with D0 (K foc = 42.3). This result could be explained by the higher content of dissolved organic matter in D300, since the addition of LCM does not change the organic matter content in the soil. The results of the field trials showed that D300 adsorbed the highest amount of dimethenamid in the upper layer of soil, and that the amount of dimethenamid in leachates was lower than that of D0. The results showed that high doses of amendment contribute to higher herbicide retention in the topsoil, reducing leaching.