The effectiveness of plant metabolites extracted from plants on larvae of the first age at Colorado beetle

Abstract

Metabolic extracts obtained from plants harvested in preparation causes mortality between 67-100% over the same extracts made from plants harvested the year before. The same phenomenon was observed in all variants Repellent who used plants harvested in 2014, and those collected in 2013, only the extract from Tanacetum vulgare L. affected by this phenomenon. Also consumption increases exponentially leaf variants harvested in 2013. These phenomena were determined in the laboratory may lead to the idea that some plants by storing a longer period of time may lose some or transformed into other substances chemical combinations leading ultimately to the differences in mortality of larvae. Since we are tempted to say that the plant extracts are preserved better in alcohol and no in water, knowing very well the maintenance of its property, from the results presented herein just the opposite: larval mortality was higher by 10- 30% in the extracts obtained in water at some alternatives to those obtained in alcohol