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Codling moth (Cydia pomonella L.): investigations on diapause and hibernation | [Le carpocapse des pommes (Cydia pomonella L.): études sur la diapause et l'hibernation]
1999
Hoehn, H. ((Swiss Federal Research Station for Fruit Growing Viticulture and Horticulture, Waedenswil (Suisse))) | Graf, B. | Hoepli, H.U.
In the present study diapause, hibernation and spring emergence of the codling moth Cydia pomonella L. have been investigated in order to improve the forecasting system. It could be shown that under Swiss conditions diapause entrance extended over three months from early July to the end of September. When protected during hibernation winter mortality was mainly caused by fungal diseases and increased with a delay in diapause entrance. In spring males and females emerged more or less simultaneously. The dispersed emergence pattern could partly be explained by the scattered diapause entrance in the previous year, but was mainly due to different temperature conditions at the hibernation sites. Accordingly the prediction of spring emergence could be improved when the temperature sum was based on stem temperature instead of air temperature
Afficher plus [+] Moins [-]Optimising the control of rosy apple aphid Dysaphis plantaginea (Pass.) (Homoptera: Aphididae) | [Optimisation de la lutte contre le puceron cendré du pommier Dysaphis plantaginea (Pass.) (Homoptera: Aphididae)]
1999
Graf, B. ((Swiss Federal Research Station for Fruit Growing Viticulture and Horticulture, Waedenswil (Suisse))) | Hoehn, H. | Hoepli, H.U.
The rosy apple aphid Dysaphis plantaginea was identified as one of the major pest problems in Swiss apple orchards. Field and lab experiments were carried out in 1996 and 1997 with the objective to improve the control strategy in general and the risk assessment in particular. Based on hatching experiments under controlled conditions a simple temperature sum method was developed to optimise the timing of pre-bloom aphid monitoring and control measures. Artificial infestations were applied to establish a time specific damage threshold. Preliminary results confirm the observation that D. plantaginea, though harmful during the period of cell division, can be tolerated in higher populations in summer
Afficher plus [+] Moins [-]Genetic flexibility of plant chloroplasts
1999
Frey, J.E. (Swiss Federal Research Station for Fruit-Growing, Viticulture and Horticulture, Department of Zoology and Weed Science, 8820 Wadenswil (Switzerland))
The smaller fruit tortrix, Grapholita lobarzewskii: predicting the phenology of adult emergence
1999
Graf, B. (Swiss Federal Research Station for Fruit-Growing, Viticulture and Horticulture, Waedenswil (Switzerland).) | Hoepli, H.U. | Hoehn, H.
Host-plant susceptibility to the carrot fly, Psila rosae. 2. Suitability of various host species for larval development
1999
Degen, T. | Stadler, E. | Ellis, P.R. (Swiss Federal Research Station for Fruit-Growing, Viticulture and Horticulture, CH-8820 Wadenswil (Switzerland))
Effects of high apple rust mite population densities on gas exchange, yield, fruit quality, tree growth and flower formation | [Effets de densités élevées des populations de phytopte libre du pommier sur les échanges gazeux, le rendement, la qualité des fruits, la croissance des arbres et la formation des fleurs]
1999
Spieser, F. ((Swiss Federal Research Station for Fruit Growing Viticulture and Horticulture, Waedenswil (Suisse))) | Graf, B. | Hoehn, H. | Hoepli, H.U.
Effects of high Apple Rust Mite (ARM) (Aculus schlechtendali Nalepa) populations on leaf damage, single leaf gas exchange, yield, fruit quality, flower formation and tree growth were investigated on the varieties Jonagold and Golden Delicious. The experiments were carried out during three years with trees that were grown under field conditions and artificially infested with ARM. All investigated parameters were significantly affected by ARM's. The influence of ARM populations on long term parameters such as flower formation and tree growth increased from the first to the second year. Golden Delicious seems to be more tolerant to high ARM population densities than Jonagold
Afficher plus [+] Moins [-]Host-plant susceptibility to the carrot fly, Psila rosae. 3. The role of oviposition preferences and larval performance
1999
Degen, T. | Stadler, E. | Ellis, P.R. (Swiss Federal Research Station for Fruit-Growing, Viticulture and Horticulture, CH-8820 Wadenswil (Switzerland))
Host-plant susceptibility to the carrot fly, Psila rosae. 1. Acceptability of various host species to ovipositing females
1999
Degen, T. | Stadler, E. | Ellis, P.R. (Swiss Federal Research Station for Fruit-Growing, Viticulture and Horticulture, CH-8820 Wadenswil (Switzerland))
Recommendations for an efficient plant protection programme in Swiss apple orchards: current state and future development of a decision support system | [Recommandations pour un programme de protection efficace des vergers de pommiers suisses: état actuel et développement à venir d'un système d'aide à la décision]
1999
Graf, B. ((Swiss Federal Research Station for Fruits Growing Viticulture and Horticulture, Waedenswil (Suisse))) | Hoehn, H. | Siegfried, W. | Hoepli, H.U. | Holliger, E.
[Recommandations pour un programme de protection efficace des vergers de pommiers suisses: etat actuel et developpement a venir d' un systeme d' aide a la decision].
1999
Graf B. | Hoehn H. | Siegfried W. | Hoepli H.U. | Holliger E.
