Cotton Aphid (Homoptera:aphididae) Treatment Threshold Incorporating Natural Enemies in Arkansas Cotton
نویسندگان
چکیده
A 12-acre field at the Delta Branch Station in Clarkedale, AR, was subdivided into 16 plots, each ~ 0.75 acre in size (56 rows x 63 m). The experiment consisted of four treatments: (1) untreated control, (2) fungicide treated, (3) conventional threshold, and (4) experimental threshold; with four replicates in a Latin square design. The fungicide treatment was used in an attempt to disrupt the action of the aphid fungus (Wells et al., 2000). Conventional plots were treated when >50% of the plants were infested and aphid populations were increasing (Johnson, 2001). Experimental plots were treated when the conventional threshold was reached and aphid densities exceeded: 15 aphids/ leaf IF “no” fungus, parasitoids or coccinellids; 30 aphids/leaf IF “no” fungus, 10% mummies, 1 coccinellid adult/row-m, 0.6 coccinellid larvae/row-m; 50 aphids/leaf IF
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