RESUMEN
Date palm trees, their cultivation and harvesting have become challenging due to infestations caused by some specific mites including Oligonychus afrasiaticus (McGregor) (Tetranychidae). Current research has been carried out to investigate the efficiency of nine pesticides against eggs and date palm mite, Oligonychus afrasiaticus against nine pesticides. Side effects of the nine pesticides were also examined on predatory mite, Amblyseius swirskii Athias-Henriot (Phytoseiidae). Mites and their eggs were treated with the recommended dosage of nine pesticides namely, Bifenazate 24%, Bifenthrin 10%, Matrine 0.6%, Imidacloprid 37% + Abamectin 3%, Sulphur 99.5%, Micronized Sulphur 80%, Mineral oil 95%, Pyrethrin 1.5% and Hexythiazox 10%, while they were present in their natural environment on the date palm trees in the experimental fields. Highest mortality of 91.16% was observed when O. afrasiaticus was treated with Bifenazate (24%) followed by 87.31%, 85.20%, 72.06%, 71.34%, 65.35%, 64.14%, 61.06% and 24.25% in case of Bifenthrin 10%, Matrine 0.6%, Imidacloprid 37% + Abamectin 3%, Sulphur 99.5%, Micronized Sulphur 80%, Mineral oil 95%, Pyrethrin 1.5%, and Hexythiazox 10%, respectively. A minimum hatching of 25.74% was observed when eggs of O. afrasiaticus were treated with Hexythiazox 10% and the highest success of hatching (99.07%) was seen when treatment was given with Imidacloprid 37% + Abamectin 3%. When same trials with same nine pesticides were performed on predatory mite; Amblyseius swirskii, the highest mortality in terms of percentage reduction (75.63%) was observed with Bifenthrin and the lowest (14.69%) with Matrine. Nine pesticides used in this study have distinct toxicity against targeted mite, their eggs and the predatory mite. A two steps control strategy is recommended for this treatment. First spray Hexythiazox at the egg laying stage and then at the moving stage of mites by using Matrine which is toxic to mites but negligibly toxic to predatory mites. Further studies are recommended to evaluate varied actions of the pesticide against eggs, phytophagous mites, and predatory mites.
Asunto(s)
Acaricidas , Ácaros , Neonicotinoides , Animales , Ácaros/efectos de los fármacos , Phoeniceae , Tetranychidae/efectos de los fármacos , Piretrinas , Alcaloides/farmacología , Nitrocompuestos , Ivermectina/análogos & derivados , Ivermectina/farmacología , Matrinas , Quinolizinas/farmacologíaRESUMEN
Alkaloid contents of leaf and seed samples of eight species of Sophora native to New Zealand, plus Sophora cassioides from Chile are reported. Fifty-six leaf and forty-two seed samples were analysed for alkaloid content by proton nuclear magnetic resonance spectroscopy, which showed major alkaloids as cytisine, N-methyl cytisine and matrine. GC analyses quantified these and identified further alkaloid components. The alkaloids identified were cytisine, sparteine, and matrine-types common to Sophora from other regions of the world. Cytisine, N-methyl cytisine, and matrine were generally the most abundant alkaloids across all species with seeds containing the highest concentrations of alkaloids. However, there was no clear taxonomic grouping based on alkaloid composition. A quantitative analysis of various parts of two Sophora microphylla trees showed that the seeds were the richest source of alkaloids (total 0.4-0.5% DM), followed by leaf and twig (0.1-0.3%) and then bark (0.04-0.06%), with only low amounts (<0.02%) found in the roots. This study represents the most comprehensive phytochemical investigation of New Zealand Sophora species to date and presents data for three species of Sophora for which no prior chemistry has been reported.