【作者】 郑伟；

【导师】 戴良英； 蔡永强；

【作者基本信息】 湖南农业大学 ， 植物保护， 2008， 硕士

【摘要】 火龙果（Hylocereus undatus Britt.＆Rose）是一种新兴的热带、亚热带果树,它集水果、花卉、蔬菜、保健为一体,有很高的经济价值。在火龙果科研和生产中我们发现,火龙果发展刚起步,处于零星种植时,病害的发生相对较轻,但是近年来在比较集中连片种植的地块,火龙果的病害发生、流行有进一步加剧的趋势。据初步调查,贵州省种植区火龙果植株已受到多种病原菌的侵染为害,严重影响植株的生长,甚至有些病害会导致植株的死亡,威胁着火龙果的生产。本研究拟就贵州火龙果病害的发生情况进行调查和鉴定,并研究其发生规律,旨在为开发火龙果病害的防治技术提供理论依据。通过2007～2008年对贵州省火龙果病害的调查和防治研究,初步确定了该省火龙果上的病害有:火龙果茎枯病（Mycosphaerella sp.（Phoma sp.））、火龙果茎斑病（Septogloeum sp.）、火龙果黑斑病（Alternaria sp.）、火龙果软腐病（Erwinia）、火龙果病毒病、火龙果生理性病害、火龙果冷害。其中以火龙果茎枯病、火龙果软腐病、火龙果茎斑病为主要病害。通过对三种病害的系统调查,对火龙果主要病害的发生症状及发生规律进行了研究,明确了引起火龙果主要病害的关键因子和防治措施。对三种病害的防治应以农业防治为主,化学防治为辅,注重消灭初侵染菌原,并结合检疫措施,选育抗病品种,必要时进行药剂防治。对火龙果茎枯病和茎斑病的化学防治采取室内药剂筛选和田间药效试验相结合,在火龙果茎枯病的药剂抑制试验中,6种药剂在高浓度下具有较好的抑制效果,最好的是50%福美双WP,依次为50%多菌灵·硫WP、70%川东甲托WP、42%克菌净WP、70%代森锰锌WP和75%百菌清WP,EC₉₀依次为537μg/mL、1259μg/mL、1259μg/mL、3162μg/mL;42%克菌净WP和75%百菌清WP EC₉₀依次为4677μg/mL、5843μg/mL效果较差。在茎斑病药剂抑制试验中,5种药剂在高浓度下具有较好的抑制效果,最好的是42%克菌净WP,依次为50%多菌灵·硫WP、50%福美双WP、70%代森锰锌WP和70%川东甲托WP,EC₉₀依次为1071.52μg/mL、1412.54μg/mL、4466.84μg/mL、4677.35μg/mL和8 317.64μg/mL。根据室内药剂抑制试验,选择出适合的药剂和浓度对火龙果茎枯病和茎斑病进行了田间药效试验,得出以下结果:在火龙果茎枯病发病初期用50%福美双WP400μg/mL、500μg/mL和50%多菌灵·硫700μg/mL、900μg/mL任选一种药剂浓度每隔7d喷一次药,共喷3次药,对防治火龙果茎枯病有着良好的效果,在生产上可推广应用。火龙果茎斑病在发病初期用42%克菌净500μg/mL,每隔7d喷一次药,共喷3次,可达到较好的防治效果,在生产上可推广应用。对火龙果茎腐病主要采取农业防治,及时清除病残体,减少病菌的繁殖、传播和蔓延。在发病初期及时修剪和刮除腐烂部位,然后对伤口喷施杀菌剂,可达到较好的防治效果。更多还原

【Abstract】 As a new tropical and subtropical fruit tree, pitaya （Hylocereus undatus Britt. & Rose） for integrating with fruits, flowers, vegetables, health care, and has a quite high economic value. In recent years, viewed from development of ecological and high-efficiency agriculture, and characteristic and fine fruit, more attentions are paid to research pitaya. It was found that the diseases occurred relatively lighter when scattered planted, but a bit more serious when centralized planted. According to the preliminary investigation, planting areas of pitaya in Guizhou province had harmful infection from many pathogenic bacteria, which seriously affected the growth of plants, even led to the death, so gave a great threaten to the production of pitaya. The investigation and identification of diseases in Guizhou pitaya and theirs occurrence regularity were studied in this paper to master some protective technologies and provide a theoretical basis for disease control of pitaya.Disease in pitaya mainly include stem blight （Mycosphaerella sp.（ Phoma sp））, stem spot （Septogloeum sp）, soft rot （Erwinia）, black spot （Alternaria sp.）, virus disease, physiological disease, chilling injury and so on, among which the first three kinds were the main pitaya disease according to the investigation during 2007 2008. Additional, the taking place symptom and regularity of the main three diseases in pitaya were made systematic investigation to further understand the key factors to lead disease and take effective measures to control disease.Agricultural measures should be raised primarily as the main control strategy, and chemical measures play a supporting but subsidiary role on the prevention and control of the three diseases. First, paying more attention to the eradication of primary infectious pathogen. Second, selecting resistant varieties, controlling-test with medicament should be carried out when necessary. Chemical control of stem blight and stem spot disease in pitaya should be combine screening of indoor fungicide with field control effect. In the process of trail on fungicide suppression of stem blight, 6 kinds of fungicides in high concentrations were found to have better inhibitory effect, among which, 50% Thiram WP was the best, and others successively were 50% Carbendazim·sulfur WP, 70% Thiophanate Methyl WP, 42%Kejunjing WP, 70% Mancozeb WP and 75% Chlorothalonil WP, followed by EC90 of 537μg/mL, 1259μg/mL, 1259μg/mL, 3162μg/mL, but 42% Kejunjing WP and 75% Chlorothalonil WP, followed by EC₉₀ of 4677μg/mL, 5843μg/mL were less effective. Correspondingly, based on the test of fungicide suppression of stem spot, 5 kinds of fungicides in high concentrations were found to have better inhibitory effect, among which, 42% Kejunjing WP was the best, and others successively were 50% Carbendazim WP, 50% Thiram WP, 70% Mancozeb WP and 70% Thiophanate Methyl WP, followed by EC90 of 1071.52μg/mL, 1412.54μg/mL, 4466.84μg/mL, 4677.35μg/mL and 8317.64μg/mL. According to the indoor test of pharmaceutical inhibition, some suitable fungicide and its concentration for the stem blight and stem spot diseases in pitaya had been selected to carry out the field controlling effect. Results showed that 50% Thiram WP with concentration of 400μg/mL and 500μg/mL or 50% Carbendazim·sulfur WP with concentration of 700μg/mL and 900μg/mL can all achieve the best control effect at the preliminary stage of stem blight disease in pitaya. Moreover, 42%Kejunjing WP with concentration of 500μg/mL had the best control effect at the preliminary stage of stem spot disease in pitaya. All of the Chemicals with different concentrations were carried out every seven days, for three times, and can be popularized and applied in production. Agricultural measures were usually taken to control stem rot disease in pitaya, which can effectively reduce propagation, transmission and spreading of the disease. Pruning in time and removing rotten position at the beginning of stem rot, then spraying fungicides for the wound, thus can also achieve a better control effect.更多还原