CROP DISEASE CONTROL BY SPRAYING ELECTROLYZED STRONG ACID WATER IN PROTECTED CULTIVATION

研究了NaCl稀水溶液电解得到的电解强酸水（ESAW, pH: 2.8，游离有效氯浓度（ECC）： 32 ppm，氧化还原电位（ORP）： 1120 mV）喷施对塑料棚黄瓜叶片白粉病和霜霉病发生的影响。每隔3天或4天将不同数量的ESAW或井水喷洒到叶子上。在第11天，单株喷施1剂和21剂ESAW可显著降低黄瓜叶片白粉病的发病率；与井水和控制水相比，喷洒了40%的水。喷施ESAW对霜霉病的防治效果为25 d，对井水的防治效果为10 d以上，对对照的防治效果为7 d以上。然而，喷洒ESAW在第15天之后引起了一些叶片类似烧伤的生理紊乱，并且在第25天，无论喷雾量如何，其百分比都达到了50%左右。这些结果表明，ESAW可用于控制某些作物病害，并可作为某些农用化学品的可行替代品，或有效减少某些农用化学品的施用量和/或频率，但仍存在类似烧叶的生理失调问题。研究了不同ph值和ECCs喷施水对作物白粉病和灰霉病严重程度的影响，以及对叶片烧伤样生理疾病发生的影响，为ESAW阐明作物病害的主要控制因素奠定基础。将ph调节水、ecc调节水或蒸馏水每隔3或4天喷洒在塑料房屋中生长的番茄叶片上。统计分析结果表明，ph < 2.7和ECC > 20ppm的主效均显著，二者对番茄白粉病的防治呈正交互作用。然而，在所有的调节水喷洒和控制之间，灰霉病的严重程度没有显著差异。在ECCs值大于20ppm或ph值小于2.7的调节水体中，部分叶片出现了烧叶样生理紊乱。少

Effects were investigated of spraying electrolyzed strong acid water (ESAW ; pH : 2.8, free effective chlorine concentration (ECC) : 32 ppm, oxidation-reduction potential (ORP) : 1120 mV), which was obtained by electrolysis of a NaCl dilute water solution, on the incidence of powdery mildew and downy mildew on/in leaves of cucumber grown in a plastic house. Different amounts of the ESAW or well water were sprayd onto the leaves once every third or fourth day. The incidence of powdery mildew on cucumber leaves was significantly reduced on day 11 by spraying 1 and 2l of ESAW per plant compared with control (no spray) ; and spraying 4l of that compared with well water and control. The incidence of downy mildew was controlled for 25 days by spraying the ESAW regardless of the amount sprayd and was delayd more than 10 days against well water and more than 7 days against control. However, spraying the ESAW caused a leaf-burn-like physiological disorder in some leaves after day 15 and the per … More centage reached around 50% on day 25 regardless of the amount sprayd. These results indicate that ESAW can be used for controlling some crop diseases and can be then a viable alternative for some agricultural chemicals or be effective in reducing application amounts and/or frequencies of some agricultural chemicals although there remains the problem of a leaf-burn-like physiological disorder.Effects of spraying waters with different pHs and ECCs on the disease severity of powdery mildew and gray mold, and on the incidence of a leaf-burn-like physiological disorder were also investigated as a fundamental research to clarify the main factor controlling crop diseases by ESAW.pH-regulated water, ECC-regulated water, or distillled water was sprayd at intervals of 3 or 4 days on leaves of tomato grown in a plastic house. A statistical analysis of the results showed that main effects of pHs lower than 2.7 and ECC more than 20ppm were significant individually, and that there was a positive interaction between the two factors on the control of powdery mildew oll tomato leaves. However, there were no significant differences in the disease severity of gray mold among all the regulated waters sprayd and control. The leaf-burn-like physiological disorder was observed in some leaves with all the regulated waters with ECCs of more than 20 ppm or with pHs of less than 2.7. Less