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. 1999 Feb 2;96(3):980–985. doi: 10.1073/pnas.96.3.980

Figure 3.

Figure 3

Rapid responses of thrips to natural and supplemental UVB from experiments carried out with the 1997 crops (all cultivars combined). (A) Soybean crops grown either with (SUN pretreatment) or without solar UVB (−UVB pretreatment) had their filters changed at flowering, when the plots were covered with either UVB-transparent or UVB-opaque films (SUN and −UVB treatments, respectively). The filter change was performed at 1000 h on 6 May 1997; the bars indicate the average number of insects counted in each treatment (T)/pretreatment (P) combination 8 h later (the thin bar indicates the SE; n = 4 plots per T × P; 10 randomly selected upper canopy leaves per plot). (B) Rapid effects of UVB irradiation on thrips densities. To create the different treatments, UVB lamps were covered with either Mylar, cellulose diacetate, or polyethylene films (see Materials and Methods). The Mylar filter blocks UVC and UVB radiation but lets through the small amount of UVA emitted by the lamps (UVAr); the cellulose diacetate filter blocks the UVC but lets through most of the UVB and UVAr emitted by the lamps (UVAr + UVB), whereas the polyethylene film is also transparent to the small amount of UVC (UVCr) produced by the UVB lamp (UVAr + UVB + UVCr). The bars show the average thrips density (6 repeated measurements for each treatment) before and at the indicated times after turning the UVB lamps on; the P values shown indicate the significance of the irradiation effect; the thin bars indicate the SEs calculated from the ANOVA. The experiment was replicated on 3 different days with similar results; the results shown are from an experiment carried out on 8 May 1997. (C) Effects of UVB and UVA irradiation. The different treatments were created as follows: no UV = 1 UVB313 + 1 TL/05 lamps covered with a 2-mm thick polycarbonate sheet (Lexan, General Electric, Mt Vernon, IN); UVAr + UVB = 1 UVB313 lamp wrapped with a diacetate filter; UVA = 1 UVB313 + 1 TL/05 lamps wrapped with a Mylar film; UVA + UVB = 1 UVB313 lamp + 1 TL/05 lamps wrapped with a diacetate film. The bars show the average thrips density (16 randomly selected leaves per treatment; thin bar indicates SE) before and 120 minutes after turning the lamps on (experiment carried out on 15 May 1997).