石河子地区菟丝子种类鉴定、生物学特性研究及生防菌筛选
发布时间：2019-07-06 21:05
【摘要】：目的:明确石河子地区菟丝子种类、生物学特性并筛选出对菟丝子强致病的生防菌株及高效化学药剂,为新疆菟丝子的防治提供理论和技术支持。方法:从石河子市内及其周边采集菟丝子茎、花和种子,采用形态学与分子生物学(ITS、rbc L、trn L-F序列分析)对其进行鉴定;通过盆栽试验和田间观察,掌握石河子地区主要种单柱菟丝子和田野菟丝子菟丝子的生物学特性及发生规律;采集自然发病的菟丝子病样,进行组织分离,致病性测定、形态学及分子生物学鉴定;对获得的分离物进行强致病菌株的筛选,并对筛选获得的强致病菌株进行了生物学特性研究和田间防效测定;采用不同浓度喷洒试验在小区筛选高效防治化学药剂。结果:1、从石河子地区共采集了37份菟丝子样品,并将其鉴定为两个种:田野菟丝子Cuscuta.campestris和单柱菟丝子Cuscuta.monogyna。其中田野菟丝子大部分寄生在草本植物上,单柱菟丝子既能寄生木本植物,又能寄生在草本植物上。2、种子吸水率试验结果说明:2种菟丝子大部分种子种皮不透水,种子具有物理休眠特性;单柱菟丝子划破种子在-4-35℃均能发芽,在30℃时,总萌发率为最高。田野菟丝子划破种子在温度低于10℃时不萌发,在25℃时,总萌发率为最高。25℃时,两种菟丝子芽长均为最长;不同光照条件对单柱菟丝子和田野菟丝子种子的最终萌发率和芽长均无显著影响,但在不同光照条件下单柱菟丝子嫩芽的颜色存在差异,在持续光照和光暗交替(16/8 h)条件下呈浅紫色,持续黑暗条件下呈白色(无色),持续暗光条件下呈淡黄色。不同光照条件对田野菟丝子嫩芽颜色均无显著影响;当土壤含水量为30%时,单柱菟丝子和田野菟丝子的萌发率和芽长均达到最高值。3、菟丝子种子在4月下旬至5上旬连续的春雨后,开始大量萌发出土,6月份至8月份开花。单柱菟丝子和田野菟丝子结果到果实成熟分别需要40 d和20 d左右。4、采集了159份菟丝子病样并将其归类为三种典型症状,进行组织分离获得123个分离物。经致病性测定获得96个致病菌,其中交链格孢菌Alternaria alternata为优势种,共62个,占致病菌的64.5%;不等弯孢菌Curvularia inaequalis 13个,占13.5%;金黄壳囊孢菌Cytospora chrysosperma 2个,占2.08%;串珠镰刀菌Fusarium verticillioides17个,占17.7%;其他2个,占2.08%。经过离体接种和小区试验,筛选出3株致病性较强的致病菌,即交链格孢菌k4-1,串珠镰孢菌m5和不等弯孢菌d1-3。这3株致病菌的悬浮液处理寄生在榆树上的单柱菟丝子后,发现15 d均能使菟丝子死亡,防效可以达到100%。5、单柱菟丝子的4株高效生防菌株k4-1、d1-3、m5和腐烂病菌株y2-3的菌丝适宜生长的温度范围为25-30℃,最适菌丝生长的温度为25℃。菌株m5分生孢子在25℃萌发率最高,菌株k4-1和d1-3在30℃萌发率为最高;菌株k4-1、d1-3和m5孢子萌发率随相对湿度增加而增大;菌株d1-3、k4-1、m5和y2-3菌丝在p H值为4-12时均能生长,菌株m5适宜菌丝生长p H值范围为7-11,菌株d1-3和k4-1适宜菌丝生长p H值范围为5-10,菌株y2-3适宜菌丝生长p H值范围为4-6。适宜菌株k4-1、d1-3和m5孢子萌发p H值范围为6-9。以上4种菌株对菟丝子常见寄主安全性测定结果表明,4种菌株对无伤口寄主苦豆子、月季、榆树、丁香和赤楠等均安全,无致病性。6、41%草甘膦异丙胺盐AS 410、820 mg/L、10.8%精喹禾灵EC 67 mg/L、苯·唑·2甲钠275 mg/L对菟丝子防效高,对寄主榆树安全,效果较为理想。
文内图片：
图片说明：菟丝子种子形态特征(A，田野菟丝子；B，单柱菟丝子)
[Abstract]:Objective: To study the species and biological characteristics of the sericin in Shihezi area and to screen the biocontrol strains and high-efficiency chemical agents which are highly pathogenic to the silk and to provide the theoretical and technical support for the prevention and treatment of the sericin in Xinjiang. Methods: The stem, flower and seed were collected from the city of Shihezi and its surroundings. The morphology and molecular biology (ITS, rbc L, trn L-F sequence analysis) were used to identify them. To master the biological characteristics and the law of the main species of the single-column and the field-type silk and silk in the Shihezi area, and to collect the disease-like samples of the natural disease, to conduct tissue separation, pathogenicity measurement, morphology and molecular biology identification; The obtained isolate is screened for strong pathogenic bacteria, and the biological characteristic research and field control effect measurement are carried out on the strong pathogenic bacteria strain obtained by screening; and the chemical agent is effectively and effectively prevented from being screened in a cell by using different concentration spraying tests. Results:1. A total of 37 samples were collected from Shihezi area and identified as two species. In that field, most of the grass of the field of the field is parasitic on the herb, and the single-column filament is not only parasitic on the woody plant, but also can be parasitic on the herb. The results showed that the germination rate was the highest at the temperature of-4-35 鈩
本文编号：2511324
文内图片：
图片说明：菟丝子种子形态特征(A，田野菟丝子；B，单柱菟丝子)
[Abstract]:Objective: To study the species and biological characteristics of the sericin in Shihezi area and to screen the biocontrol strains and high-efficiency chemical agents which are highly pathogenic to the silk and to provide the theoretical and technical support for the prevention and treatment of the sericin in Xinjiang. Methods: The stem, flower and seed were collected from the city of Shihezi and its surroundings. The morphology and molecular biology (ITS, rbc L, trn L-F sequence analysis) were used to identify them. To master the biological characteristics and the law of the main species of the single-column and the field-type silk and silk in the Shihezi area, and to collect the disease-like samples of the natural disease, to conduct tissue separation, pathogenicity measurement, morphology and molecular biology identification; The obtained isolate is screened for strong pathogenic bacteria, and the biological characteristic research and field control effect measurement are carried out on the strong pathogenic bacteria strain obtained by screening; and the chemical agent is effectively and effectively prevented from being screened in a cell by using different concentration spraying tests. Results:1. A total of 37 samples were collected from Shihezi area and identified as two species. In that field, most of the grass of the field of the field is parasitic on the herb, and the single-column filament is not only parasitic on the woody plant, but also can be parasitic on the herb. The results showed that the germination rate was the highest at the temperature of-4-35 鈩
本文编号：2511324
本文链接：https://www.wllwen.com/kejilunwen/nykj/2511324.html
