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The aims of this work were (i) to find a soil indicator to predict durum wheat yield response to Zn fertilization, (ii) to compare the effect of various Zn fertilization strategies on wheat yield and Zn biofortification in calcareous Vertisols of southern Spain, and (iii) to assess the effect of these Zn fertilization strategies on crop P uptake (durum and bread wheat). Different Zn fertilization strategies, soil application (0.3–10 kg ha−1) and foliar spraying (two rates, different growth stages), were tested in wheat crops under field conditions in the period 2012–2019. A simple soil indicator failed to predict durum wheat response to Zn fertilization. Only one of the combinations tested increased wheat yield in the 11 field experiments carried out. Zinc foliar spraying (1.28 kg ha−1) was effective for wheat biofortification when applied at early booting (durum wheat) or flowering, and also when splitting this application between stem elongation and flowering stages (bread wheat). The foliar treatments produced the highest zinc use efficiencies (6–19%) and soil applications the lowest (0.2–1.3%). Moreover, foliar treatments increased grain Zn concentrations by 12–51% while soil application increased such concentrations by only 4–13%. None of the Zn fertilization strategies altered P uptake. No yield increase in wheat is expected from Zn fertilization for the application methods and rates used here and the soils studied (calcareous Vertisols under Mediterranean climate). However, foliar applications at and after early booting stage are promising for durum and bread wheat biofortification.

The grapevine moth (Lobesia botrana) is the most significant pest of viticulture. This article reports the development of an analytical method that allows the instrumental determination of the three main pheromone components of the pest ((E,Z)-7,9-dodecadien-1-yl acetate, (E,Z)-7,9-dodecadien-1-ol and (Z)-9-dodecen-1-yl acetate) in grape-related samples (must, table grape and wine grape). The combination of headspace, gas chromatography and mass spectrometry provides limits of detection in the range of 60–420 ng/Kg and precision, expressed as a relative standard deviation, better than 8.5%. This analytical approach is rapid and simple and opens a door to the study of the pest incidence on the final products.