Kaolin reflectant treatments have been shown to reduce stress due to the environment, pests, and pathogens in many plants. We tested the effect of kaolin on yield, beet curly top virus (BCTV) incidence, and physiological parameters (measured as hyperspectral reflectance) of field-grown chile pepper (Capsicum annuum L.) in southern New Mexico. Curly top incidence was significantly lower in kaolin-treated chile blocks than untreated blocks. Peppers treated with the kaolin-reflectant showed significantly less water stress and higher photochemical reflectance than untreated plants during active growth periods. Treated plants had significantly higher levels of chlorophyll a and higher reflectance than untreated plants. Yield from treated plants was not significantly different from that from untreated plants. We did not detect any deleterious effects on peppers due to application of kaolin. Kaolin treatments suppressed beet curly top virus on chile and reduced water stress parameters during the hottest months of the growing season, suggesting that it would be useful in New Mexico chile production in years with moderate disease pressure.

Hyperspectral reflectance data were used to detect internal infestations of Angoumois grain moth, Sitotroga ceralella (Olivier), in wheat kernels. Kernel reflectance was measured with a spectroradiometer over a wavelength range of 350–2500 nm. Kernel samples were selected randomly and scanned every 7 d after infestation to determine the ability of the hyperspectral reflectance data to discriminate between infested and uninfested kernels. Immature stages of S. ceralella inside wheat kernels can be detected through changes in moisture, starch, and chitin content of the kernel. By using the spectrally-derived moisture variable (Log[1/R972nm]-Log[1/R1032nm]) and starch variable (Log[1/R982nm]-Log[1/R1014nm]), it was possible to discriminate between infested and uninfested wheat kernels with 100% classification accuracy based on 90% confidence intervals. Significant differences in the spectral reflectance between the infested and uninfested kernels were due to changes in moisture and starch content in wheat kernels. Three of the four chitin variables showed slight discrimination between the infested and uninfested wheat kernels based on 90% confidence intervals with 63.9%, 68.8%, 66.7%, and 41.6% classification accuracy of the three variables (Log[1/R1130nm]-Log[1/R1670nm]), (Log[1/R1139nm ]-Log[1/R1320nm]), (Log[1/R1202nm]-Log[1/R1300nm]), and (Log[1/R2046nm]-Log[1/R2302nm]), respectively. Spectral reflectance changes as a function of wheat kernel position relative to the spectroradiometer sensor did not differ significantly (P > 0.10).

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Effect of Beauveria bassiana on Rhyzopertha dominica parental adult mortality, F1 emerged adults, wheat kernels weight loss and damage were evaluated. Lesser grain borer, R. dominica adults were exposed to B. bassiana (BIOVER ®) conidia powder admixed with wheat kernels in different six rates w/w (weight of B. bassiana conidial powder to weight of wheat kernels) and compared to untreated (check). Mortality percentage of R. dominica adults increased with increasing rates of B. bassiana after seven days. Significant differences were observed between all tested B. bassiana rates (P=0.0001). The maximum percentage of adult mortality after seven days of exposure was achieved at the highest rate compared to the untreated. Same trend was recorded after 14 days of exposure (P= 0.0001) at the previously mentioned rates compared to the untreated check. Negative relationship between B. bassiana rate and number of emerged R. dominica adults was recorded. Significant difference (P= 0.0001) was recorded between the untreated and the treated mean numbers of adult progeny emerged. The maximum adult progeny emerged was observed in the lowest rate (0.1% w/w) averaged 100.33 adult, while the minimum adult progeny emerged was recorded in the highest rate (1.0% w/w) averaged 16 adult compare to the untreated (225.33 adult). Weight loss means varied significantly among the tested rates of B. bassiana. Increasing B. bassiana rates led to significant decrease in weight loss on wheat treated. The minimum percentage of weight loss was recorded in the highest rate (1.0% w/w) compared to the untreated wheat which showed more feeding activities of the R. dominica beetles. In addition, the untreated wheat grains infested with R. dominica was significantly more damaged by the feeding of beetles than grains treated with B. bassiana. Generally, B. bassiana treated wheat kernels significantly decrease in mean numbers of F1 emerged adult, weight loss and damage compared to untreated wheat kernels. As an alternative control method of stored product insect pests, B. bassiana could be implicated as a part of integrated pest management (IPM) strategies.

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