Control of Witches'-broom Disease of Jujube with Oxytetracycline Injection

Oxytetracycline 수한주입에 의한 대추나무 비짜루병 방제

A Witches'-broom disease of jujube (Zizyphus jujuba) with which mycoplasma-like bodies are associated is wide spread in South Korea. Jujube trees with witches'-broom symptoms were selected from 15-20 year old planting and treated with solution of oxytetracycline hydrochloride (Terramycin). Treatments were 1) one injection on April; 2) one postharvest injection on October; 3) two injections (April and July); 4) three injections (April, June and August) and 5) an untreated control. Each injection consisted of 500ml of 1,000 p.p.m. solution of oxytetracycline HCl transfused into affected trees from plastic reservoir through plastic tubes connected to 3 small holes drilled in the basal part of the tree trunks. Complete remission of witches'-broom symptoms was accomplished within one growing season by one spring (April) injection. One postharvest (Oct.) injection also prevented the symptoms in the following growing season. Two and three injection treatments prevented the symptoms for at least two growing seasons and restored previously severely diseased trees to normal or near normal conditions. Remission of symptoms was found only above the injection site while current season witches'-brooms developed from areas below the injection site and from untreated main scaffolds. The results of this experiment demonstrates that transfusion treatment with oxytetracyclin HCl is feasible for the practical control of witches'-broom of jujube.

oxytetracycline HCI의 대추나무 비짜루병 방제효과를 구명할 목적으로 병든 대추나무(15-20년생, 흉고직경 20cm 내외)에 oxytetracycline HCI의 1,000 p.p.m. 수용액을 1회에 500ml씩 시기별로 각각 1회(4월), 2회(4월, 7월), 30(4월, 6월, 8월) 그리고 대추 수확후 1회구(10월)로 나누어 수간에 주입하여 다음과 같은 결과를 얻었다. 1. 수간주입당년에 있어서는 시기별 주입회수에 관계없이 1회 이상의 수간주입으로 비짜루병징이 완전히 억제되고, 정상엽이 자라나면서 개화결실하였다. 2. 2회이상 주입한 나무와 10월에 1회주입한 나무에서는 이듬해 가을까지도 병징억제효과가 지속되었으나 4월에 1회 주입한 나무에서는 이듬해에 부분적으로 경미한 병징이 나타나기 시작했다. 3. oxytetracycline HCI에 의한 병징억제효과는 수간주입부위의 윗쪽에서만 나타났으며, 그 이하부위와 약액이 주입되지 않은 측지에서는 병징이 억제되지 않았다. 4. oxytetracycline HCI의 5.000 p.p.m. 수용액을 주당 30ml씩 주입하였을 때는 전혀 병징이 억제되지 않았다.