Research
Row Cover results for 2001

Trapping and Other Strategies for Management of Striped and Spotted Cucumber Beetles in Iowa Muskmelons 

Traps were placed in two concentric rings 50 and 65 feet outside of the muskmelon field.  We also tested three other management methods in combination with the traps. 

Treatment 1: Reemay (opaque, white fabric) stretched over hoops at the time of planting
Treatment 2: Slitted plastic row covers stretched over hoops at the time of planting
Treatment 3:  BioYield, a soil inoculant that includes a variety of plant growth-promoting rhizobacteria.

The experiment was planted on black plastic at the ISU Horticulture Farm; the Southwestern Research and Demonstration Farm in Castana; and the Muscatine Island Research Station in Fruitland.  Each location included two fields, a trapping field and a control field, with four replications of the treatments included in each field.  Yellow sticky cards placed in each plot were counted and replaced at the same time the traps were counted and emptied, once per week through the end of harvest.  Bacterial wilt ratings (number of wilted plants per plot) were taken at the first sign of disease at Ames; there were very low levels of disease at Castana and Muscatine.

              The most convincing evidence for the success of the traps at Ames is the difference in bacterial wilt incidence between the trapping and control fields at that location.  There was 36% more wilt in the control field than in the traps field.  Overall, there were also fewer beetles found in the field with traps than the field without (Table 1).  This was reflected in yield only at Ames, where there was much greater beetle and bacterial wilt pressure than at Castana or Muscatine.  There were also fewer wilted plants in the trapping field than in the control field at Ames.  The effect of the row covers and BioYield-treated soil on beetle populations was minimal, though the slitted row covers did seem to increase yield at Muscatine and Castana.  This increase may have been due to temperature increases, however, since it was not correlated with a decrease in beetle populations or bacterial wilt.  Another year of data would be useful in understanding why these row covers increased yield, as well as the mechanism by which the traps reduce bacterial wilt. 

Mean total weight (marketable + cull), marketable weight, number of marketable melons, and marketable melon weight in a single plot for the traps and control fields at three Iowa locations.

Location

Field

Total Weight
(lbs)

Marketable Weight
 (lbs)

Quantity (melons)

Average Weight (lbs/melon)

Ames

Traps Field

 156.1 A

    141.8 A

   26.8 A

   5.3 B

 

Control Field

 115.9 B

      99.4 B

   15.1 B

    6.6 A

 

LSD (α = 0.05)

        30.2

  28.2

 4.7

0.7

Castana

Traps Field

208.2 B

211.4

35.0

6.1

 

Control Field

248.1 A

234.2

40.1

5.9

 

LSD (α = 0.05)

        27.5

             31.7

 5.3

0.5

Muscatine

Traps Field

132.5 B

    89.5 B

   18.3 B

4.9

 

Control Field

159.1 A

   144.1 A

  27.4 A

5.3

 

LSD (α = 0.05)

        21.3

19.1

        3.6

0.3