The present research, continuing that reported in [2], deals with the spray application subject, so to investigate as volume rate and airflow rate, forward speed being equal, affect the foliar deposition in an espalier vineyard. Experimental trials were carried out by means of an air assisted towed sprayer, equipped with “Albuz ATR” nozzles. To take into account the influence of the development of the trees, the field trials were replicated in two phenological stages with an interval of about one month: “Inflorescences fully developed” (stage 1) and “Beginning of berry touch” (stage 2). A full factorial experiment was carried out for each growth stage, with two airflow rates (3.9 and 7.5 m3/s), three volume rates (103, 216, and 276 L/ha in the first growth stage and 154, 330 and 432 L/ha in the second growth stage), and four replicates, arranged according to a randomised complete block design. Working pressure (1.2 MPa) and forward speed (1.4 m/s) were kept unchanged for all the trials. The foliar deposition was measured by means of a spectrophotometric technique. The leaves were sampled on two depth layers and two or three heights, according to the trees’ development. The results showed that volume rate did not significantly influence the mean foliar deposition in both the two growth stages, while the highest deposits were obtained with the lowest airflow rate. The airflow rate × volume rate interaction, though not statistically significant, showed that low volume rates together with high airflow rates, result in a noticeable reduction in foliar deposition (29% with respect the grand mean), due to an increase of the spry drift, especially at the first growth stage, when the foliar development is little. These second tests, unlike those described in [2], did not show any positive influence of the airflow rate on the foliar deposition in the inner part of the canopy, so further investigations could be necessary to better understand the results. The whole results suggest to operate in field at low airflow rates (some 3.9 m3/s) and low volume rates (some 25 L/ha per active nozzle), so to reduce the power requirements and increase the promptness of intervention.
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机译：本研究是在[2]中继续进行的研究，涉及喷洒应用主题，因此，以体积速率和气流速率，前进速度相等的情况进行研究，以影响西班牙葡萄园中的叶片沉积。通过配备有“ Albuz ATR”喷嘴的空气拖曳式喷雾器进行了试验。考虑到树木发育的影响，在两个物候阶段重复进行了田间试验，间隔大约一个月：“花序充分发育”（第1阶段）和“浆果接触开始”（第2阶段） 。在每个生长阶段进行了全因子试验，两个气流速率（3.9和7.5 m3 / s），三个体积速率（第一个生长阶段分别为103、216和276 L / ha）和154、330和432 L / ha在第二个生长阶段），并根据随机完整块设计安排了四个重复。在所有试验中，工作压力（1.2 MPa）和前进速度（1.4 m / s）均保持不变。通过分光光度法测量叶面沉积。根据树木的发育情况，在两个深度层和两个或三个高度上对叶子进行了采样。结果表明，在两个生长阶段，体积速率均不会显着影响平均叶面沉积，而气流速率最低则沉积量最高。气流速率×体积速率的交互作用虽然不具有统计学意义，但显示出低体积速率和高气流速率会导致叶片沉积量显着减少（相对于平均平均值为29％），这是由于spry漂移的增加，尤其是在叶片发育很少的第一个生长阶段。与[2]中描述的那些不同，这些第二项测试没有显示出气流速率对冠层内部叶面沉积的任何积极影响，因此可能需要进一步研究以更好地理解结果。总体结果表明，应在低风量（大约3.9 m3 / s）和低风量（每个活动喷嘴大约25 L / ha）的条件下进行现场操作，从而降低功率需求并增加干预的及时性。
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