The development and implementation of sustainable and environmentally friendly agricultural practices are indispensable as alternatives to pesticide use and to keep populations of soil-borne plant pathogens at levels ...The development and implementation of sustainable and environmentally friendly agricultural practices are indispensable as alternatives to pesticide use and to keep populations of soil-borne plant pathogens at levels that do not affect crop productivity.The present research evaluates the incidence of soil-borne phytopathogens on the pineapple variety MD-2,which was subjected to different treatments:Incorporation of Crotalaria juncea into the soil(organic amendment),application of dolomitic lime to soil(inorganic amendment),and the use of plastic mulch covering the soil.During the crop cycle(15 months),the following variables were evaluated:plant height(cm),fruit weight(kg·plant^(−1)),crop yield(ton·ha^(−1)),the bud root disease incidence caused by Phytophthora nicotianae,number of soil phytoparasitic nematodes and colony-forming-units(CFUs)of soil fungi and oomycetes.The results indicate that Crotalaria juncea treatment reduced the pathogen population(nematode and oomycetes)at levels that did not affect crop development,so that yield increased(18–20%).The incorporation of C.juncea into the soil as an organic amendment favors the populations of fungi disease suppressors(Trichoderma-Aspergillus).The phytoparasitic nematodes(Meloidogyne sp.,Pratylenchus sp.,and Mesocriconema sp.)and oomycetes(Phytophthora spp.,and Pythium spp.)showed a reduction of their population levels by effects of organic amendment(C.juncea).The plastic mulch was also effective,probably due to the maintenance of optimal condition to crop growth and weed control.However,the dolomitic lime application had the poorest effect under the conditions of the study area on the variables analyzed.The described observations are characteristics of a system-based approach for the potential management of soil-borne pathogens of pineapple MD-2 in Veracruz,México.展开更多
Root-Knot Nematodes （RKN） Meloidogyne spp. significantly affects glasshouse tomatoes in Central Greece. Elimination or halting J2s could be an efficient strategy to control RKN. Recently, it was reported that a comm...Root-Knot Nematodes （RKN） Meloidogyne spp. significantly affects glasshouse tomatoes in Central Greece. Elimination or halting J2s could be an efficient strategy to control RKN. Recently, it was reported that a commercial product of Neem （Azadirachta indica） seed extract （Azadirachtin 1% Emulsion Concentrate-EC） significantly reduced the number of galls on tomato roots and egg masses, compared to the untreated control. In the present study neem proved to have a direct immobilising effect on RKN J2s. Different concentrations （0, 0.05, 0,1, 0.25, 0.5, I, 5, 10, 25 and 50%） of the tested neem product were applied with water containing fresh J2s and in soil naturally infected with RKN. Records of immobilised J2s were taken after 10 min, 1 h, 6 h, 24 h and 72 h of Neem application in water and after six days of neem application into the soil. Neem solution concentrations 5% and 10%, resulted in 85% ± 3.2 and 100% of immobilised J2s. The same concentrations of neem when were added in the water for nematode extraction from the soil, resulted 14.25% ± 4.01 and 1.7%, of J2s extracted from the soil with a significant concentration effect （P = 0.008）, compared to the untreated control. However, the neem product at high application dose significant damage the tomato plants caused phytoxicity.展开更多
文摘The development and implementation of sustainable and environmentally friendly agricultural practices are indispensable as alternatives to pesticide use and to keep populations of soil-borne plant pathogens at levels that do not affect crop productivity.The present research evaluates the incidence of soil-borne phytopathogens on the pineapple variety MD-2,which was subjected to different treatments:Incorporation of Crotalaria juncea into the soil(organic amendment),application of dolomitic lime to soil(inorganic amendment),and the use of plastic mulch covering the soil.During the crop cycle(15 months),the following variables were evaluated:plant height(cm),fruit weight(kg·plant^(−1)),crop yield(ton·ha^(−1)),the bud root disease incidence caused by Phytophthora nicotianae,number of soil phytoparasitic nematodes and colony-forming-units(CFUs)of soil fungi and oomycetes.The results indicate that Crotalaria juncea treatment reduced the pathogen population(nematode and oomycetes)at levels that did not affect crop development,so that yield increased(18–20%).The incorporation of C.juncea into the soil as an organic amendment favors the populations of fungi disease suppressors(Trichoderma-Aspergillus).The phytoparasitic nematodes(Meloidogyne sp.,Pratylenchus sp.,and Mesocriconema sp.)and oomycetes(Phytophthora spp.,and Pythium spp.)showed a reduction of their population levels by effects of organic amendment(C.juncea).The plastic mulch was also effective,probably due to the maintenance of optimal condition to crop growth and weed control.However,the dolomitic lime application had the poorest effect under the conditions of the study area on the variables analyzed.The described observations are characteristics of a system-based approach for the potential management of soil-borne pathogens of pineapple MD-2 in Veracruz,México.
文摘Root-Knot Nematodes （RKN） Meloidogyne spp. significantly affects glasshouse tomatoes in Central Greece. Elimination or halting J2s could be an efficient strategy to control RKN. Recently, it was reported that a commercial product of Neem （Azadirachta indica） seed extract （Azadirachtin 1% Emulsion Concentrate-EC） significantly reduced the number of galls on tomato roots and egg masses, compared to the untreated control. In the present study neem proved to have a direct immobilising effect on RKN J2s. Different concentrations （0, 0.05, 0,1, 0.25, 0.5, I, 5, 10, 25 and 50%） of the tested neem product were applied with water containing fresh J2s and in soil naturally infected with RKN. Records of immobilised J2s were taken after 10 min, 1 h, 6 h, 24 h and 72 h of Neem application in water and after six days of neem application into the soil. Neem solution concentrations 5% and 10%, resulted in 85% ± 3.2 and 100% of immobilised J2s. The same concentrations of neem when were added in the water for nematode extraction from the soil, resulted 14.25% ± 4.01 and 1.7%, of J2s extracted from the soil with a significant concentration effect （P = 0.008）, compared to the untreated control. However, the neem product at high application dose significant damage the tomato plants caused phytoxicity.
