青海青稞主栽品种(系)对条纹病和云纹病的抗性鉴定

本研究旨在明确青海青稞主栽品种和后备品种对条纹病和云纹病的抗性,以期为抗病育种及田间病害防治提供理论依据。试验采用田间自然病圃法,对青海主栽的30个青稞品种(系)进行了条纹病和云纹病田间抗性鉴定。结果表明,供试青稞品种(系)对2种病害的抗性存在显著差异,但缺乏免疫品种。对条纹病表现高抗的有13个品种(系),占鉴定总数的43.3%,其中主栽品种有3个,即‘门农1号’、‘昆仑13号’、‘巴青1号’。品系17发病率最低。对云纹病表现高抗的有品系1、品系2、品系6、品系17、品系28、RQKQ-3、RQKQ-5、RQKQ-6、RQKQ-7、RQKQ-8、‘门农1号’、‘互青2号’、‘北青6号’和‘昆仑10号’,共14个,其病情指数均在10以下;表现中抗的共有8个,分别为品系5、品系11、RQKQ-1、RQKQ-9、‘巴青1号’、‘北青3号’、‘北青7号’和‘昆仑13号’。     

加工型辣椒品种对细菌性叶斑病的抗性鉴定

由黄褐假单胞Pseudomonas fulva侵染引起的辣椒细菌性叶斑病是近期在新疆北疆加工辣椒生产区发现的一种新病害。为评估辣椒品种对细菌性叶斑病的抗性水平,采用苗期人工接种结合田间调查,鉴定了生产中13个主栽辣椒品种对细菌性叶斑病的抗性。结果表明,供试材料对细菌性叶斑病均无免疫性,但不同辣椒品种对辣椒叶斑病抗性差异较大,‘改良佳线1号’和‘丰力红冠’为抗病品种;‘佳线4号’、‘新丰6号’、‘秦椒王’、‘陕早红’、‘宝丰2号’为耐病品种;‘红安6号’、‘朝天椒’为感病品种,高感品种为‘金塔’、‘铁皮椒’、‘红龙13’和‘超级韩国甜椒’。研究结果为辣椒的抗病育种和病害防治提供了基础。     

冀西北地区燕麦主栽品种（系）抗秆锈病鉴定

2011-2012年,在2个试验点,采用孕穗期接种混合菌种的方法,对冀西北地区40个燕麦主栽品种（系）抗秆锈病进行了鉴定。结果表明：9个皮燕麦品种中,‘冀张燕5号’、‘冀张燕2号’、‘坝燕1号’、‘冀张燕1号’和‘定燕1号’等5个品种,31个裸燕麦品种（系）中,‘白燕2号’、‘白燕11号’、‘冀张莜6号’、‘冀张莜12号’、‘花晚6号’、‘晋燕14号’和‘燕科1号’等7个品种,至少在1个试验点表现免疫、抗病或慢病,其中大多在温度较低的试验点1更抗病,认为与大多数燕麦抗秆锈病基因表现低温抗病性有关;其余28个品种（系）均表现感病或高度感病。     

辽宁花生品种对疮痂病抗性及流行时间动态分析

为明确辽宁花生产区栽培品种对疮痂病抗性差异及病害发生流行规律,通过田间小区试验,采用五点调查法对不同花生品种疮痂病田间发生情况和时间流行动态进行了系统研究.结果表明,供试18个品种花生疮痂病病情指数存在显著差异,其中主栽品种白沙1016病情指数最高,可达34.5,新花2号病情指数最低,仅为15.7.根据花生疮痂病相对抗性评价标准,供试品种整体分为3类,高感品种4份,感病品种6份,中抗品种8份,未发现免疫和高抗品种.病害发生规律表现为:7月初为始发期,7月下旬至8月下旬为病害盛发期,8月末至9月上旬为病害衰退期.Logistic模型能够较好地描述花生疮痂病病情指数随时间的流行动态,依据模型公式也推导出主栽品种白沙1016的病情指数最大,日增长量为0.89.     

临麦系列春小麦品种抗条锈性分析

小麦条锈病是发生于甘肃省临夏州小麦生产上的最主要病害,种植抗病品种是防治该病最经济有效且有利于保护环境的措施。作者于2013年在甘肃省农业科学院植物保护研究所兰州低温温室和甘谷试验站进行了苗期、成株期分小种接种鉴定,并于2010-2014年对临麦系列春小麦品种‘临麦32号’~‘临麦36号’在甘肃省不同生态区的8个试验点进行成株期抗条锈性分析,结果表明:春小麦品种‘临麦32号’苗期对所有供试菌系均表现感病,成株期对CYR29和CYR32表现中抗-中感;‘临麦33号’除对CYR29苗期表现免疫、成株期表现中抗-中感外,对其余供试菌系均表现感病。对自然诱发的条锈病,两品种也表现感病;‘临麦34号’和‘临麦36号’除对新菌系G22-9、G22-14表现感病外,对其余菌系表现抗病,但自2013年开始两品种在田间也表现感病;‘临麦35号’全生育期对接种及自然诱发的条锈菌均表现抗病。苗期选用24个国内外供试条锈菌单孢菌系进行基因推导分析,发现供试临麦系品种抗性谱与已知基因载体品种的抗性谱均不一致,初步推测供试临麦系品种含有未知抗条锈基因。     

黄淮南片麦区主栽小麦品种对赤霉病抗性分析

为明确黄淮南片麦区主栽小麦品种对赤霉病的抗性水平。采用人工接种鉴定的方法对黄淮南片的河南、安徽、陕西和江苏四省的65份主栽小麦品种进行赤霉病抗性鉴定,经土表接种抗侵染型鉴定,中抗品种有‘徐农0029’、‘西农511’和‘保麦6号’,中感品种有‘徐麦31’、‘瑞华520’和‘西农3517’等18份,高感品种44份;经单花滴注接种抗扩展型鉴定,中抗品种为‘西农511’,中感品种有‘烟5158’、‘西农889’、‘西农2000’等14份,高感品种50份。由此可见,黄淮南片麦区主栽小麦品种对赤霉病抗性普遍较差,建议根据各地赤霉病发生程度,选择适宜抗性指标,结合现代育种技术,逐步提高主栽小麦品种的抗性水平。     

云南主栽核桃品种对Alternaria alternata叶枯病的抗病性评价

为了解云南地区不同核桃品种对叶枯病的抗性,从而为核桃抗病品种选育和叶枯病的防治提供依据,试验采用田间调查和离体叶片接种法获得病斑面积和病情指数,采用聚类分析的方法对田间调查和离体接种的病斑面积进行聚类分析,并结合病害分级标准,综合评价云南主栽37个核桃品种对Alternaria alternata的抗病性。结果表明:‘大泡核桃1’叶片上未出现病斑,‘小圆果’病斑面积最小,为5.05 mm~2,而‘圆菠萝2’病斑面积最大,达到887.68 mm~2;采用Ward最小偏差平方和法和欧式距离进行聚类分析,其聚类效果与接种结果和田间调查结果的吻合度最好。通过田间调查和离体接种综合评价,将37个核桃品种分为13个抗病品种、15个中抗品种、7个中感品种和2个感病品种。     

花生网斑病不同病斑类型及其病原菌致病力差异

本文描述了河南省发生日趋严重的花生网斑病在田间出现的一种新的病斑类型,并结合已报道的两种病斑类型,对3种病斑类型的病原菌开展致病力差异研究。研究结果表明:田间新发现的花生网斑病病斑特征明显,综合分析后将花生网斑病病斑类型分别定为网纹型、类褐斑型和污斑型;同一花生品种上3种病斑类型病原菌菌株间存在明显的致病力差异,同一病斑类型菌株对不同花生品种的致病力也表现出显著差异。     

河北省小麦主栽品种对茎基腐病抗性鉴定及评价指标相关性分析

为明确河北省小麦主栽品种对假禾谷镰刀菌Fusarium pseudograminearum引起的小麦茎基腐病的抗性水平, 采用温室苗期与田间接种鉴定相结合的方法, 评价20份河北省小麦主栽品种的抗病性。结果显示, ‘衡0628’苗期表现为抗病, ‘山农22’等6个品种苗期表现为中抗, ‘冀麦585’等5个品种成株期表现为中抗, ‘石麦15’和‘藁优5766’ 2个品种在苗期和成株期均表现为中抗。抗性指标相关性分析结果显示, 苗期病情指数与茎基部组织中病原菌DNA含量有极强的相关性, 成株期病情指数与白穗率有显著相关性。本研究结果表明, ‘石麦15’和‘藁优5766’两个品种的抗性水平较高, 且抗性稳定, 可利用苗期茎基部组织中病原菌DNA含量及成株期白穗率分别作为评价小麦茎基腐病苗期及成株期抗性的指标之一。     

不同苜蓿品种对镰孢菌的抗性鉴定

为探明苜蓿不同品种对能引起苜蓿根腐病的茄镰孢(Fusarium solani)、半裸镰孢(F. semitectum)、弯角镰孢(F. camptoceras)等3种镰孢菌的抗性差异,提供筛选抗耐病性材料的新来源,通过室内盆栽法,对30个苜蓿品种(系)进行了苗期抗病性鉴定,结果表明,各品种之间抗病性差异显著,其中‘德里兰德’、‘新疆大叶’、‘苜蓿王’对半裸镰孢表现为抗病,病情指数分别为18.11、19.93、19.96,占鉴定总数的10%;总体来看,‘猎人河’等7个品种表现耐病,病情指数为25.30～39.95,占鉴定总数的23.3%;‘甘农2号’等18个感病品种,病情指数为40.55～59.56,占鉴定品种总数的60.0%;‘德宝’等5个品种为高感,平均病情指数为61.7~68.6,占鉴定总品种数的16.7%,无免疫和抗病品种。     

大豆灰斑病叶部病害普遍率与严重度关系初步探讨

 1992~1995年在田间接种条件下对大豆灰斑病叶部发病情况进行系统调查,获得86组感病品种(合丰22)和66组抗病品种(合丰25)普遍率与严重度间对应关系数据,在计算机上分析了两者的关系(I-S关系)。结果表明,感病品种和抗病品种叶部病害的I-S关系均可用直线方程描述,其直线回归方程分别为:#br#SS_感=-2.8029+0.5252IS±6.4364(SS、IS-感病品种严重度和普遍率)#br#SR_抗=-0.3843+0.6334IR±3.7679(SR、IR-抗病品种严重度和普遍率)#br#协方差分析结果表明,大豆品种的抗病性对大豆灰斑病叶部病害的I-S关系有一定影响。     

花生叶斑病研究进展

花生叶斑病是一种世界性病害,其流行可以导致花生产量减少和品质降低。本文对花生叶斑病的发生与危害、病原菌、防治措施、遗传研究、分子标记、转基因及花生抗叶斑病种质创制等多个方面的最新研究进展进行了综述。为花生抗叶斑病研究提供参考。     

Root infection of sugar beet by <Emphasis Type="Italic">Cercospora beticola</Emphasis> in a climate chamber and in the field

Sugar beet root infection by Cercospora beticola, the causal agent of Cercospora leaf spot (CLS), was studied in a climate chamber and in the field. In the climate chamber, root incubation of susceptible seedlings with a conidial suspension resulted in disease incidences that were significantly different for two sugar beet cultivars (Auris: 0.8 ± 0.14 and A00170: 0.5 ± 0.18; P < 0.05) with regard to the control treatment 35 days after root incubation in a standard potting soil-fine river sand mixture. In a field trial with susceptible cv. Savannah with soil-incorporated CLS-infested leaf material, disease developed four weeks earlier in the infested plots than in the control plots. The probability that disease develops in the field was significantly higher for the infested than for the control plots (P < 0.05). Symptomless plants from infested field plots transferred to the glasshouse to induce leaf spot symptoms showed a significantly higher probability to induce symptom development (0.4 ± 0.08), than plants from control plots (0.02 ± 0.02) (P <0.05) 14 days after transfer. This probability was significantly higher than for plants that remained in three of the infested field plots (0.2 ± 0.04; 0.2 ± 0.05 and 0.2 ± 0.04 respectively), except for one infested field plot (0.4 ± 0.05) on July 5. We conclude that C. beticola is able to infect sugar beet seedlings through their roots and that latent CLS infections in sugar beet lead to symptom development at high temperatures (> 20 °C) and high relative humidity (> 95) in our climate chamber or after canopy closure in the field. Quantification of root infection and long term survival in soil is necessary to assess its contribution to the epidemiology and life cycle of Cercospora beticola. Cultural methods such as a wider crop rotation, management of crop debris and ploughing systems may provide control strategies alternative to or reducing fungicide input.     

喹啉铜33.5%悬浮剂防治杨梅褐斑病药效试验

田间药效试验表ql:喹啉铜33.5%悬浮剂供试药剂有效成分用量167.5~223.3mg/kg处理,防效达74%以上,可以用于防治和控制杨梅褐斑病。     

龙眼褐斑病病原及其生物学特性

 龙眼褐斑病是危害龙眼苗期的一种主要叶部病害,根据病原菌形态、致病性,鉴定此菌为Bartalinia bischofiae Nag Raj。该菌生长最适温度为25~28℃,pH值为7~9,它能有效地利用各种碳源,但以阿拉伯树胶粉最好,氮源以硝酸铵最适。分生孢子需在水中才能萌发,3%的葡萄糖溶液可促进孢子萌发,其萌发最适温度为25~28℃,pH值为5~7。     

茭白胡麻叶斑病病原菌分离与鉴定

茭白胡麻叶斑病发生普遍且严重,已成为茭白的常见病害。为了明确病原菌,先后从茭白主产区采集胡麻叶斑病病叶,各产区分离纯化5～10株病原菌。通过对菌株DNA的内转录间隔区ITS基因、3-磷酸甘油醛脱氢酶GPDH基因、延伸因子EF-1α基因的序列进行分析。结合形态学观察、致病力测定等方法对茭白胡麻叶斑病病菌进行鉴定。结果表明,茭白胡麻叶斑病病原菌为稻平脐蠕孢Bipolaris oryzae,与水稻胡麻叶斑病病原菌一致。本文的研究成果可为茭白胡麻叶斑病的防治提供一种新的思路。     

江西早熟梨病害发生调查

于2009年3月上旬至10月下旬,每月1次定期到金溪和南昌市郊调查江西早熟梨病害,共调查出早熟梨病害9种,其中以梨轮纹病发生最重,其次是梨锈病和梨角斑病。梨角斑病是近年迅速上升起来的一种病害,应加强防治和研究。     

广西香蕉真菌性叶斑病病原菌种群结构分析

2009年2-3月对广西香蕉主产区真菌性叶斑病病原进行抽样鉴定。结果显示,广西香蕉真菌性叶斑病病原至少有10种,主要病原为Cordana musae,分布广,检出率为56.77%~92.19%;Corynespora cassiicola和Deightoniella torulosa为次,两种病原菌均主要集中在南宁地区,检出率分别为32.34%和22.61%;叶斑病类型以单一病原侵染为主,检出率为78.13%~92.19%;复合侵染的叶斑病类型以2种病原共同侵染居多。     

Comparison of screening methods to evaluate the response of St. Augustine grass to Magnaporthe oryzae

The objective of this study was to develop a reliable and high throughput screening method to evaluate the response of St. Augustine grass (Stenotaphrum secundatum) genotypes to the grey leaf spot (GLS) caused by Magnaporthe oryzae infection. Whole plant, detached stolon and detached leaf assays under growth chamber conditions were compared to field conditions on eight commercial and nine advanced breeding lines of St. Augustine grass. Disease was assessed using two variables, lesion size (LS) and overall plant disease severity (SEV). LS and SEV were highly correlated for field and growth chamber screening methods using the whole plant assay (LS r² = 0·79; SEV r² = 0·83; P ≤ 0·001), the detached stolon assay (LS r² = 0·75; SEV r² = 0·72; P ≤ 0·001), and the detached leaf assay (LS r² = 0·46; SEV r² = 0·60; P ≤ 0·001). Genotypic variation for resistance in 17 St. Augustine grass genotypes was identified using all screening methods for LS (P < 0·05) and SEV (P < 0·05). The rank‐sum method was used to classify St. Augustine grass genotypes into highly resistant (HR), resistant (R), moderately resistant (MR), moderately susceptible (MS), susceptible (S) and highly susceptible (HS) classes based on the rank‐sum values of LS and SEV. Two introduced African polyploids used as parents, and two F₁ interploid progeny obtained using an in vitro embryo rescue technique, were classified as highly resistant (HR), or resistant (R), across all screening methods.     

Pesticide Residues as Hazards

Abstract

A new bacterial disease of tobacco, not previously reported was found in Karnataka. Studies on the disease initiated to identify the causal agent the factors which predispose the plants to epidemics, and control of the disease, revealed that it occurs in epiphytotic form following heavy rains after the crop has been topped, and is more severe in thicker leaves. The primary source of inoculum is the soil, and secondary spread takes place by rainwater splashing from infected to healthy plants. The disease is found predominantly in beedi tobacco and causes severe damage to the crop resulting in economic loss in yield. The causal organism is Erwinia chrysanthemi. In vitro evaluation of chemicals showed that streptomycin sulphate + chlorotetra‐cycline (Streptocycline), streptomycin sulphate (Ambystrin) and streptomycin sulphate + oxytetracycline (Paushamycin) were effective in control of the bacterial disease.