Phytotoxicity of alkaloids, coumarins and flavonoids isolated from 11 species belonging to the Rutaceae and Meliaceae families

Meliaceae and Rutaceae families are known for the high diversity of their secondary metabolites, which include many groups that represent a rich source of structural diversity, and are good candidates as sources of allelochemicals that could be useful in agriculture. In the work described here the bioactivity profiles were evaluated for 3 alkaloids (1–3), 12 coumarins (4–15), 2 phenylpropanoic acid derivatives (16 and 17) and 14 flavonoids (18–31) from 11 species belonging to the Meliaceae and Rutaceae families. All compounds were tested in the wheat coleoptile bioassay and those that showed the highest activities were tested on the STS (Standard Target Species) Lepidium sativum (cress), Lactuca sativa (lettuce), Lycopersicon esculentum (tomato), and Allium cepa (onion). Most of the isolated compounds showed phytotoxic activity and graveoline (3), psoralen (8), and flavone (18) were the most active, with bioactivity levels similar to that of the commercial herbicide Logran1. The results indicate that these compounds could be involved as semiochemicals in the allelopathic interactions of these plant species

Manejo integrado da cochonilha Diaspis echinocacti praga da palma forrageira em Brasil

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Angelo Moreira Da Costa Lima: renombrado entomologista, prot?tipo de homen bom

8 ref

Central ai lhe seed rice nematode Apho/enchoides besseyi.

Em seis experimentos conduzidos nos municípios de Lorena e Pindamoiihangaba, SP, procurou- se verificar o efeito de tratamentos químicos e térmico de sementes sobre o nematóide Aphelenchoidesbesseyi Christie 1942, em condições de cultivo irrigado. Alauns produtos e o tratamento térmico reduziram o nível populacional do nematóide, porém não houve associação entre os dados de redução e aumento na produção. As cultivares utilizadas, IR 841, IAC 435, IAC 120 e IAC 899, demonstraram elevada tolerância ao nematóide, com destaque de produtividade da IAC 899.Six triale were carried oul nt Lorena and Pindamonhangaba, SP, Brazil, to study lhe confrol of the rice nematode Aphe/encho ides besseyi Christie 1942, for irrigated conditons. Some chemicals and one thernial treatment were elteclive in decreasing nematode density nevertheless, there was no associailon with yield increases. The cultivars IR 841, IAC 435, IAC 120 and IAC 899 were very tolerant to nematode with yields prominence 01 lAC 899