Möglichkeiten und Grenzen für integrierte Pflanzenschutzmaßnahmen im Ackerbau
Meine Ausführungen sind der Versuch einer realistischen Einschätzung verbundener Anwendung der zur Zeit verfügbaren Pflanzenschutzmethoden. Trotz Uberwiegens der chemischen Maßnahmen kommen auch in der hochtechnisierten Landwirtschaft wesentliche Elemente der Hygiene zur Geltung. In welchem Tempo das Repertoire praktikabler Pflanzenschutzmaßnahmen um biologische und biotechnische Komponenten ergänzt wird, hängt in erster Linie vom Aufwand für die Forschung und wissenschaftliche Anleitung der Praxis ab. Die modernen, aufgeschlossenen Landwirte werden neue Teilsysteme in die Pflanzenschutzpläne bereitwillig einbauen, wenn sie der Zielsetzung des integrierten Pflanzenschutzes entsprechen, nämlich den höchst möglichen wirtschaftlichen Nutzen und das bestmögliche Ernteprodukt bei geringstem Aufwand zu erzielen (W e l t z i e n 1966). Es wäre illusionär, nach Lage der Dinge rasche Fortschritte in der Entwicklung und praktischen Nutzung zu erwarten. ; The analysis of all known methods of plant protection in agnculture shows that there are only few p'ossibilities for practical integrated programmes. At present only rural engineering and chemical methods can be combined with the aim of taking care of beneficial and indifferent organisms as weil as of promotion of the antiphytopathological potential. The application possibilities of the single registered biological plant pr o tectant based on Bacillus thuringiensis are strongly limited. Any other biological or biotedmica.l methods are not yet ready for use. For mass production of predators, genetically managed pests, and biological pesticides as weil as for the development of biotechnical methods from screening to !arge scale operations several times the budget presently available for integrated plant protection has to be provided. From the chemical industries only limited interest can be expected in respect to tedmological development of biological or bio-_ chemical products as weil as to commercializing the rearing of beneficial animals. The chances that attractants and selective pesticides will be synthesized are better. Commercial agriculture has to be prepared for the mange towards integrated plant protection. Most important is the readiness for renouncing procedures without solid motivation. Occasional phytosanitary controls must be replaced by regular inspection of the important pests and their antagonists. The investigation of ecological facts that cause the necessity of control methods will require a lot of knowledge, experience, and input of labour. Therefore farmers who want to ·manage plant protection in this manner will have to undergo a comprehensive basic study and periodical advanced training. The WARNDIENST, a system of the plant protection service especially operating in natural regions, can provide only little assistance for the strongly differenciated integrated programmes. The hints and appeals of the WARNDIENST can only point out tendencies. Last not least it would be desirable to abolish the contrary requirements between agricultural and food legislation on one hand and the principles of integrated plant protection on the other.