Agronomic characteristics and management of diseases in maize with chelate-based products containing calcium, copper, manganese, and zinc

ABSTRACT. The aim of this work was to verify the potential of chelate-based products containing calcium, copper, manganese, and zinc for the management of Pantoea ananatis, Puccinia polysora, Cercospora zeae-maydis, Exserohilum turcicum, Diplodia macrospora, and Pseudomonas avenae in crop maize growth in the summer season, as well as their influence on agronomic characteristics. The treatments included commercial chelate-based products of amino acids with the elements calcium (15%), copper (5%), manganese (15%), and zinc (10%) at doses of 0.5 kg ha-1, 0.3 L ha-1, 0.4 kg ha-1, and 1 L ha-1, respectively; fungicides (20% azoxystrobin and 8% cyproconazole at a dose of 0.3 L ha-1 + 25% propiconazole at a dose of 0.4 L ha-1); and water. The tests were carried out under field conditions for two consecutive years with two simple hybrids. The plant height, stem diameter, number of rows per ear, number of grains per ear row, productivity and mass of one thousand grains, as well as the severity of leaf diseases, were all evaluated, and chemical analysis of the leaves was performed. In the 2016/2017 growth season, for the number of rows per ear and number of grains per row, the fungicide treatment showed the highest values, whereas for the mass of one thousand grains and productivity, the chelate treatments did not differ from the fungicide treatment and were different from the water treatment. In the 2017/2018 growth season, for the mass of one thousand grains and yield, only the fungicide treatment was different from the water treatment. For all the chelates studied for both hybrids, there was no difference in nutrient content before and after foliar application. It can be concluded that calcium, copper, manganese, and zinc products may influence agronomic traits but not the severity of the diseases evaluated in these two hybrids of maize under the edaphoclimatic conditions in which the study was carried out.摘要 本研究旨在验证含钙、铜、锰、锌的螯合态制剂（chelate-based products）对夏季玉米生育期内菠萝泛菌（Pantoea ananatis）、玉蜀黍柄锈菌（Puccinia polysora）、玉米尾孢菌（Cercospora zeae-maydis）、玉米大斑病菌（Exserohilum turcicum）、大孢色二孢菌（Diplodia macrospora）及燕麦假单胞菌（Pseudomonas avenae）的防控潜力，同时评估其对玉米农艺性状（agronomic characteristics）的影响。 试验设置三类处理：分别以0.5 kg·ha⁻¹、0.3 L·ha⁻¹、0.4 kg·ha⁻¹及1 L·ha⁻¹的施用剂量，使用含15%钙、5%铜、15%锰及10%锌的商用氨基酸螯合态制剂；以0.3 L·ha⁻¹的20%嘧菌酯（azoxystrobin）+8%环丙唑醇（cyproconazole）与0.4 L·ha⁻¹的25%丙环唑（propiconazole）复配的杀菌剂；以及清水对照。 试验于田间条件下连续两年开展，供试材料为2个单交玉米杂种（simple hybrids）。测定指标涵盖株高、茎粗、穗行数、行粒数、籽粒产量、千粒重（mass of one thousand grains）以及叶部病害严重度（severity of leaf diseases），同时对叶片样品进行化学组分分析。 在2016/2017生育季，杀菌剂处理的穗行数与行粒数均达到最高值；而就千粒重与籽粒产量而言，螯合态制剂处理与杀菌剂处理无显著差异，但二者均显著优于清水对照。在2017/2018生育季，仅杀菌剂处理的千粒重与籽粒产量显著高于清水对照。对于两个供试杂种的所有螯合态制剂处理，叶面喷施前后的叶片养分含量均无显著差异。 综上，在本研究开展的土壤气候条件（edaphoclimatic conditions）下，含钙、铜、锰、锌的螯合态制剂可对玉米农艺性状产生调控作用，但对供试两个玉米杂种的目标病害严重度无显著防控效果。