辣椒常见病害

辣椒常见病害

青枯病

【发病特征】：植株发病时，病株顶部叶片白天枯萎，阴天或早晚恢复，2～3天后叶片保持绿色但全株枯萎。切开病茎，导管呈褐色，将切口浸在水中，从切口处流出白色混浊的菌液。【发病规律】：辣椒青枯病是一种细菌性病害，在土温达到20℃～25℃时，气温达到30℃～37℃时，土壤含水量达25%以上时发病严重。当大雨骤晴，气温迅速升高，湿度大，蒸腾量大时，病菌活动旺盛，病株增加，为害严重。病菌在土壤酸碱度为6.6时适宜发育。

【防治方法】：

1．选用抗病品种；

2．调整土壤酸碱度，亩施石灰50～100公斤；

3．实行轮作，防止重茬或连茬；

4．及时检查，发现病株立即拔除、烧毁，在穴内撒施石灰粉；发病初期可用100～200PPM 农用链霉素或春雷霉素一包兑水150市斤淋湿土壤，连续防治3次，灌根每10～15天一次，连续2～3次。

疫病

【发病特征】：在整个生育周期皆可发病，苗期染病，多发生于茎基部，苗期发病，茎基部呈暗绿色水浸状软腐或猝倒，即苗期猝倒病；有的茎基部呈黑褐色，幼苗枯萎而死；叶片染病，病斑圆形或近圆形，直径2～3厘米，边缘黄绿色，中央暗褐色；果实染病始于蒂部，初生暗绿色水浸状斑，迅速变褐软腐，湿度大时表面长出白色霉层，即病菌孢囊梗及孢子囊，干燥后形成暗褐色条斑，病部以上枝叶迅速凋萎。

【发病规律】：病菌以菌丝体、卵孢子在土壤中或病组织中越冬，卵孢子借助雨水、灌溉水溅射传播，病菌发育最适温为23℃～31℃，高温高湿有利于病菌发生。

【防治方法】：

1．若辣椒疫病是土壤传染，防治时必须用农药灌根。

2．防治的关键时间为6月中、下旬?辣椒开花盛期挂果期，一般为浇完头水后1～2天内进行灌根。

3．有效农药用25%早霜灵或58%早霜灵锰锌，浓度为500倍液灌根，每穴灌0.3～0.4斤效果最好。

白粉病

【发病特征】

辣椒白粉病由子囊菌亚门真菌鞭靼内丝白菌引起，叶片，老叶、嫩叶均可染病。在田间主要靠气流传播蔓延。稍干燥条件下该病容易流行。病叶正面初生褪绿小黄点，后扩展为边缘不明显的褪绿黄色斑驳。病部背面产出白粉状物，严重时病斑密布，致使全叶变黄，大量脱落形成光秆，严重影响产量和品质。

【防治方法】

1．种植时选择抗病性较好的品种并用新高脂膜拌种（能驱避地下病虫，隔离病毒感染，不影响萌发吸胀功能，加强呼吸强度，提高种子发芽率）。

2．种植前深翻土壤，喷洒新高脂膜800倍液杀菌消毒、保温保墒。

3．在辣椒的各个生长期要适时喷洒辣椒壮蒂灵，增强体内营养输送，提高辣椒对外界的抵抗力。

4．发病初期喷洒多氧清1000倍液加杜邦福星3000倍液并加施新高脂膜，效果尤好。

病害防治

疫病。辣椒疫病是一种毁灭性病害，如遇连日阴雨或暴雨，病害则迅速蔓延，严重成灾。（1）、主要症状：叶片病斑呈圆形或近圆形，中央暗褐色，边缘呈黄绿色，果实从蒂部开始发病，病斑为水浸状暗绿色，后变软腐。当湿度大时，叶片软腐，容易脱落，果实上长出白色霉层。

（2）、防治：发病初期，及时用58%甲霜灵锰锌可湿性粉剂500倍液或64%杀毒矾600倍液或50%代森锰锌可湿性粉剂600倍液，隔7-10天喷1次，喷2-3次，严重时，隔5-7天喷1次，喷4-5次。

应对连阴雨

[6]连阴雨对后辣椒如果管理不当，对辣椒有一定影响，主要应做好以下几方面

中耕除草、增施草木灰，降湿通气：

通过中耕，破除土壤板结，改善土壤通气状况，促进辣椒根系的发育，为辣椒生长创造良好的土壤环境。中耕时间应选择在晴天高温期或高温前进行，近根处浅，行间深，避免伤根。中耕后杂草大量失水枯死，同时又具有土壤消毒杀菌的作用。结合中耕增施草木灰，一是降低土壤湿度；二是增加土壤养分。

整枝打尖，防止落花落果：

辣椒整枝时，保留主干和2－3个侧枝，下部腋芽应全部抹除，并剪掉内膛枝、老病残枝，使内膛通风透光，在3级以上分枝留2叶打尖，新长出的枝条留1果2叶打尖，摘除下部老病叶，以促进上部枝叶生长和果实伸长膨大。同时再次培土，促发新根，并喷施2‰的尿素、磷酸二氢钾等肥料。

推株并拢，改善田间通风透光条件：

辣椒到了成熟期，由于植株生长茂密，枝条纵横交错，以及杂草清除不彻底，或管理不当等，直接影响线辣椒成熟时需求良好的通风透光条件。如不采取推株并拢解决群体郁蔽问题，尤其是阴雨连绵将会出现已丰收到手的胜利果实落果霉烂，直接影响成熟质量，造成重大的损失。因此，推株并拢是阴雨天促进辣椒红熟的关键措施。推株并拢方法：人工用两手将辣椒植株从茎基部约5厘米处，用力向两侧推压，用脚将根部踏实。但要轻手轻脚，尽量防止伤坏植株和青椒。在推株并拢的同时，可结合进行拔除杂草、捡拾落地青椒、虫病斑椒以及畸形椒。为辣椒创造一个良好的通风透光条件。

Chili Common Diseases

Bacterial wilt

【Clinical characteristics: onset of the plants the diseased top of the blade during the day wilt, cloudy or recovery sooner or later, 2 to 3 days after the leaves remain green, but the whole plant wilt. Cut stem disease, catheter brown, ,the incision is immersed in the water, outflow of the white turbidity of the bacterium from the incision.

The occurrence regularity: pepper bacterial wilt is a bacterial disease, the soil temperature reaches 20 ° C to 25 ° C, the temperature reached 30 ℃~ 37 ℃, soil water content of more than 25% of the incidence of serious. When heavy rain suddenly clear, the temperature rises rapidly, humidity, transpiration large strong germs activities, diseased plants increased, serious damage. Bacteria in soil pH of 6.6 when appropriate developmental.

[Control methods:

1. Selection of resistant varieties;

2. Adjust the soil pH, the Mushi lime 50 to 100 kg;

3. Crop rotation to prevent cropping or even stubble;

4. Timely inspection, found that the removal of diseased plants immediately, burnt lime powder applicator in the cavity; Available 100 ~ 200PPM early onset of streptomycin, kasugamycin a pack Duishui 150 Jin wet soil, continuous control of three times, IRRIGATING once every 10 to 15 days for 2 to 3 times.

Epidemic disease

Clinical characteristics: the incidence of the entire growth cycle can seedling disease occurred in the stem base, seedling disease, stem base was dark green water-soaked soft rot or damping-off, seedling damping disease; , some dark brown stem base, seedlings withered and died; leaves infected lesion round or nearly round, 2 to 3 cm in diameter, the edge of the yellow-green, the central dark brown; fruit disease began in the pedicle, newborn dark green water-soaked spots, quickly brown soft rot, white mold layer grow humidity surface germs sporangiophore and sporangia, formed after drying dark brown streaks disease above the foliage quickly wilting.

Attack Law: Pathogen mycelia and oospores in soil or diseased tissues wintering oospores With rain and irrigation water sputtering spread of germs developmental optimum temperature of 23 ℃to 31 ℃, high temperature and high humidity is conducive of pathogens.

[Control methods:

1. Phytophthora capsici is a soil-borne, prevention must the pesticide IRRIGATING.

2. Prevention and control of the critical time for a mid-June, late? Pepper flowering peak fruiting period, , generally poured the first water 1 to 2 days IRRIGATING.

3. Effective pesticide use 25% the the early frost spiritual or 58% early frost Spirit MnZn, concentration 500 times IRRIGA TING, and 0.3 to 0.4 pounds per hole irrigation works best. Powdery mildew

Clinical characteristics

Chilli powdery mildew ascomycete subphylum within the fungi whip pedaled silk white fungus caused leaves, old leaves, young leaves can be infected. In the field is spread mainly by air currents. The disease is easy to pop slightly dry conditions. Diseased leaves positive newborn chlorotic small yellow dot, after the a chlorotic yellow mottled extended to the edge of the obvious. Disease the back output white powder substance, serious lesion, clouds, causing the