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141.
Biology and Fertility of Soils - Peatlands are archives of extreme importance for the assessment of past ecological, environmental and climatic changes. The importance as natural archives is even...  相似文献   
142.
A novel, simple, and cheap method to synthesize antioxidant methacrylic-ferulic acid copolymer (PMAA-FA) by free radical polymerization was developed by employing a hydrogen peroxide-ascorbic acid pair to produce hydroxyl radicals acting as radical initiators. FT-IR spectra were performed to verify the insertion of ferulic acid into the polymeric chain, and the antioxidant activity of PMAA-FA was compared to that of a control polymer synthesized in the absence of antioxidant molecule. Good antioxidant activity was demonstrated by obtained materials, showing the efficiency of the polymerization method. This material could be useful in the pharmaceutical field and in the food industry (food packaging).  相似文献   
143.
The maize weevil Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae) is a worldwide pest on stored products, as maize, wheat and rice grains. However, in South Brazil, these weevils have been found attacking fruits in field conditions. It was reported that adults attack fruits to feeding, but there was no information of oviposition and larval development on these hosts. Furthermore, due to monitoring apple orchards, was observed that some fruits showed distinct kind of punctures, suggesting a oviposition by these weevils. The present study reports first record an unusual behavior of S. zeamais by oviposition and larval development in peach and apple fruits. The study was conducted in laboratory conditions (temperature: 25?±?1 °C, RH: 70?±?10% and photophase of 14 h). Peach and apple fruits were offered to S. zeamais females. The oviposition and duration of immature stages in peach were measured in fruits and in corn grains, used as control observation. The oviposition and larval development occurred in peach and apple fruits, with a development until to adult. The average of egg-to-adult was 47.4 d in peach and and 45.1 d apple fruits, respectively, while in corn grains, its natural host, the duration was 38.2 d. These results show that the damage caused by S. zeamais in peach and apple fruits may be due to oviposition and the development of immature stages. So, the novelty is in demonstrating that the maize weevil does not just feed as an adult opportunistically on the fruits, but can complete a full life cycle using fresh fruits.  相似文献   
144.
Precision Agriculture - Laser-controlled land leveling (LLL) can help improve rice production's spatial and temporal management, leading to optimized water and crop management. This research...  相似文献   
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