. Boll rüsselkäfer Unterdrückung, Verwaltung und Beseitigung Technologie: Verfahren der Konferenz, Februar 13-15, 1974, Memphis, Tennessee. Boll Rüsselkäfer, Kontrolle, Kongresse. Copiah Co.1972. 6/27 7/5 7/12 7/19 7/26 8/1 8/7 8/14 8/21 DATUM Abbildung 1.-Daten von Copiah County Experiment. Diese beiden Farmen. Wir pflanzten 90 Morgen Fries Deckblatt und 128 Hektar normale Deckblatt. Wir con-ummantelt bug-catcher (Traktor montiert) Probenahme von jedem Feld für mehrere Wochen. Am 13. Juni die Baumwolle wurde Anfang pinhead Plätze zu haben. Am 19. Juni haben wir einen Durchschnitt von 42 wee-VILS pro Morgen in jeder der 12 Fries und

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. Boll weevil suppression, management, and elimination technology : proceedings of a conference, February 13-15, 1974, Memphis, Tennessee. Boll weevil, Control, Congresses. Copiah Co. 1972. 6/27 7/5 7/12 7/19 7/26 8/1 8/7 8/14 8/21 DATE Figure 1.—Data from Copiah County experiment. these two farms. We planted 90 acres of Frego bract and 128 acres of normal bract. We con- ducted bug-catcher (tractor mounted) sampling of each field for several weeks. On June 13 the cotton was beginning to have pinhead squares. On June 19, we caught an average of 42 wee- vils per acre in each of the 12 Frego and 12 normal fields. Since we were on farmer fields being used for commercial production, this level of infestation called for an application of insec- ticide. Between June 20-23 one-fourth pound of methyl parathion was applied to each field. After this application, each of the 24 fields was sprayed only when the level of egg-damaged squares exceeded 10 </c. The overall results were a 50 % reduction in oviposition-damaged squares per acre and 46 % fewer applications of insecti- cide were used in the Frego than in normal bract. The yield was equal in the Frego bract and nor- mal. One grower's yield was slightly less than the others, but equal for each type. The detailed week-by-week population figures are shown in figure 1. Above each data point on the graph for Frego and normal are shown the number of fields (reps) of each cotton type out of 12 that required insecticide in a given week. In the Frego bract, after the initial application to all 12 fields on June 20, there were two fields on July 5, three fields on August 1, and six fields on August 7 that required insecticide. Beginning on August 14 all 12 fields were in need of boll weevil insecticides. The picture was quite dif- ferent on the normal bract. After the initial ap- plication to all 12 fields on June 20, there were three fields that required insecticide on July 5, and on July 19 all 12 fields needed insecticide fo

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