不同油茶种和品种对炭疽病的抗性观察

在林间调查了广东省内栽培的高州油茶、广宁红花油茶和39个品种的普通油茶对油茶炭疽病的抗病性,并在室内研究了高州油茶、广宁红花油茶和9个品种的普通油茶叶片对炭疽病的抗病性。林间自然状态下调查结果表明,广宁红花油茶对炭疽病的抗病性最强,普通油茶‘粤韶77-1号’、‘铁城1号’和‘湘林1号’抗性中等,其他品种均表现为感病;室内测定结果表明,广宁红花油茶属于抗病种类,‘铁城1号’和‘粤韶77-1号’属于中度抗病品种,其他为感病品种。     

不同百合品种对百合灰霉病的抗病性鉴定

为明确不同百合品种对灰霉病的抗病能力,本试验采用离体叶片菌丝块接种和田间孢子液喷雾2种方法测定了百合7个不同品种对百合灰霉病的抗病性。离体测定结果表明,供试的7个品种对百合灰霉病的抗病性存在显著差异,其中‘法兰西’和‘罗蒂娜’为高感品种,‘康斯坦萨’和‘索邦’为高抗品种,‘马可波罗’、‘提拔’和‘西伯利亚’为中抗品种;田间接种发病的测定结果除‘西伯利亚’为高抗品种外其余结果与离体接种结果一致;离体接种和田间接种发病情况的系统调查分析得知,感病品种‘法兰西’和‘罗蒂娜’发病早,病情发展速度快,病情指数高;‘提拔’、‘康斯坦萨’、‘西伯利亚’和‘索邦’等抗病品种发病晚,病情发展缓慢,病情指数低;随着品种抗病性的增强,发病速度和病情指数逐渐降低。     

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。     

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。     

芒果叶片对炭疽病的阶段抗性

为了研究芒果叶片对炭疽病的阶段抗性,在室内人工接种和田间自然发病条件下,对3个芒果品种的不同成熟度叶片的抗病性进行了鉴定,并测定了病原菌分生孢子在不同成熟度叶片表面的萌发率和附着胞形成率.结果表明,在室内人工接种条件下,随着芒果叶片逐渐成熟,对炭疽病的抗性逐渐增强,处于幼嫩期的古铜色叶片最为感病,病情指数在97.0以上,淡绿色叶片表现抗病,病情指数在2.0～2.5之间,成熟的老叶表现高抗或近免疫,病情指数为0.田间自然发病调查结果与室内试验结果基本一致,说明幼嫩的古铜色阶段是芒果叶片对炭疽病的易感期.随着芒果叶片成熟度的提高,病原菌分生孢子萌发率和附着胞形成率有下降的趋势,在古铜色叶片、淡绿色叶片和老叶表面分生孢子萌发率分别为98.1%～99.2%、95.0%～97.0%和86.0%～92.0%,附着胞形成率分别为74.4%～81.0%、70.0%～77.8%和63.4%～69.9%.     

香蕉枯萎病抗性品种及绿色药剂的初步筛选

为筛选抗枯萎病香蕉品种, 通过伤根、针刺及淋菌法接种香蕉枯萎病菌4号小种, 进行盆栽试验, 结果表明, 品种‘巴西蕉’和‘南天红’的病情指数较高, 分别达 42.5和 37.5, 为中感品种; 而品种‘南天青’和‘南天黄’病情指数仅为15, 为抗病品种; ‘农科一号’病情指数最低, 仅为7.5, 是5个品种中最抗病的, 为高抗品种。为筛选防治香蕉枯萎病的绿色药剂, 选用壳聚糖水剂、竹醋液、耕保泰对比络氨铜水剂对‘巴西蕉’进行盆栽药效试验, 结果表明, 耕保泰防治效果较好, 相对防效达78.57%; 20%竹醋液的防治效果最差, 仅为35.71%。     

不同方法对14个苜蓿品种抗蚜评价分析

本试验研究了抗蚜株率、感蚜指数和改进的感蚜指数3种评价方法对14个苜蓿品种抗蚜评价的影响。结果表明:以抗蚜株率为标准,‘甘农9号’抗性最好;以感蚜指数为标准,‘阿尔冈金’抗性最好。而采用改进后的感蚜指数评价方法可将14个苜蓿品种分为7个等级,其中‘WL-319’为高感品种,‘巨能Ⅱ’为感虫品种,‘新牧4号’‘甘农5号’‘WL-354’‘WL-363’为低感品种,‘新牧1号’为中间品种,‘甘农9号’为低抗品种,‘MF4020’为中抗品种,‘中苜1号’‘WL-343’‘阿尔冈金’‘苜蓿王’‘SK3010’为高抗品种。改进后的感蚜指数评价方法符合“1±0.1”等差数列分级标准,使不同抗性级别符合正态分布,具有统计学意义。同时,该方法充分考虑了天敌对蚜虫发生量的影响,在生产实践中具有重要的推广应用价值。     

辣椒疫病抗性的浸根接种鉴定方法

为建立规模化的辣椒疫病苗期抗性鉴定技术, 将辣椒疫霉人工接种于抗疫病辣椒品种‘ICPN21-03’和感病辣椒品种‘B16144’, 研究了接种菌液浓度?接种时期?病情调查时期和接种方法等对人工接种鉴定效果的影响?结果表明, 接种菌液游动孢子浓度为10个/mL时, 感病品种病情指数为73.37, 可以满足寄主发病的需要; 1 ~ 10真叶期接种均能使植株发病, 但5 ~ 6真叶期接种能反映抗感病品种真实抗性; 接种5 d调查抗感病品种病情指数分别为9.32和73.37, 可明显区别抗感病品种?使用浸根法进行鉴定, 需菌量小, 对接种环境要求小?用37个辣椒品种进行验证, 鉴定结果表明该苗期抗性鉴定技术可很好地对辣椒品种进行抗性水平分级鉴定?     

部分葡萄品种酸腐病田间发病情况调查

酸腐病是近年来在我国葡萄生产上严重发生的病害之一,引起中后期果穗腐烂,严重影响了葡萄的产量和质量。2010-2011年笔者调查了北京地区24个不同葡萄品种酸腐病的田间发生情况,并对病情指数进行了差异显著性和聚类分析,结果发现:11个酿酒葡萄品种聚为3类。第1类,‘小味尔多’、‘小芒森’和‘赤霞珠’病情指数最低(2.08～4.17);第2类,‘胡桑’、‘阿拉奈尔’和‘品丽珠’病情指数居中(5.83～9.17);第3类,‘长相思’、‘佳美’、‘雷司令’、‘梅鹿辄’和‘维奥尼’病情指数最高(16.25～20.00)。13个食用葡萄品种也聚为3类。第1类,‘茉莉’、‘红伊豆’、‘巨峰’和‘黑奥林’发病最轻,病情指数最低(1.00～5.00);第2类,‘世纪无核’、‘玫瑰香’、‘龙宝’、‘黄意大利’、‘京蜜’、‘金香玉’和‘魏可’病情指数居中(7.00～10.67);第3类,‘里扎马特’和‘亚都蜜’,发病最重,病情指数最高(15.67～18.00)。试验为葡萄酸腐病的田间防治提供了依据。     

烟草嫁接苗对黑胫病的抗性鉴定

嫁接技术是植物病害绿色防控的有效措施之一,为探寻抗烟草黑胫病的高抗嫁接组合,本研究以4个高抗烟草品种为砧木,生产上4个主栽品种为接穗,开展了不同嫁接组合烟苗对黑胫病的抗性鉴定。人工接种黑胫病菌后,以‘Florida 301’作砧木时烟苗发病率和病情指数分别为0~4.76%和0~2.86;以‘革新3号’作砧木时分别为0~20.71%和0~15.72;以‘Beinhart 1000-1’作砧木时分别为1.11%~13.18%和1.11~11.47;以‘L8’作砧木时分别为20.02%~65.33%和13.58~60.89,而以接穗品种‘K326’、‘云烟87’、‘NC55’和‘红花大金元’自根苗的发病率和病情指数分别为:‘K326’,39.98%和35.46,‘云烟87’,45.81%和39.18,‘NC55’39.33%和35.93,‘红花大金元’,74.67%和65.48。统计分析结果表明,以‘Florida 301’、‘革新3号’和‘Beinhart 1000-1’品种为砧木的嫁接苗发病率与病情指数均极显著低于接穗品种自根苗(P0.01);‘L8’品种为砧木时,只有‘云烟87’作接穗的发病率与病情指数极显著低于‘云烟87’自根苗(P0.01)。采用平板涂布计数法,对抗、感黑胫病烟草品种根际微生物数量进行了测定,研究了抗、感病品种根际微生物群落结构,结果表明,抗、感病品种均是根际细菌根际放线菌根际真菌,且根际细菌、放线菌数量远多于真菌数量,抗病品种的根际微生物数量整体上多于感病品种。     

Hymenopteran Parasitoids on Fruit-infesting Tephritidae (Diptera) in Latin America and the Southern United States: Diversity, Distribution, Taxonomic Status and their use in Fruit Fly Biological Control

We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.     

Brief Guide for Authors

正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad     

The parasitoid complex ofLiriomyza cicerina on chickpea (Cicer arietinum)

Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.     

Plant–herbivore asynchrony necessitates augmentative releases of the exotic beetle,Zygogramma bicolorata,to enhance the biological control of P arthenium hysterophorus

Systematic information on the quantitative impact of Z ygogramma bicolorata on the biology of P arthenium hysterophorus is crucial as the seeds of this weed continue to germinate from the accumulated soil seed bank throughout the year in the form of different germinating flushes, while the activity of the beetle ceases during winter as it enters diapause. Therefore, plant–herbivore interactions need to be explored to develop predictions of the overall impact of the introduced beetle on the weed. The findings revealed that defoliation by Z . bicolorata had a significant impact on the plant height, density and flower production in flushes F ₃, F ₄ and F ₅, but not in F ₁ and F ₂ that exhibited longer periodicity, profuse branching, a longer flowering period and maximum flower production and contributed mostly to the existing seed soil bank. Therefore, total depletion of the existing soil seed bank was not possible. Consequently, the effect of augmentative field releases of laboratory‐reared beetles was explored on F ₁ and F ₂ in February for three consecutive years (2011–2013). Before initiating the trial, random soil samples were taken from the plots that were assigned to the paired treatments (i.e. with the beetle and without the beetle [insecticide‐treated]) and it was found that the seed bank in those samples did not differ. The single release of Z . bicolorata adults at five per plant at the six‐leaf stage significantly reduced the soil seed bank, compared to without the biocontrol agent, irrespective of the flushes at the end of the season.     

Effects of the saprophytic leaf mycoflora on growth and productivity of winter wheat

The effects of the saprophytic mycoflora and its interference with cereal aphids on growth and yield of winter and spring wheat was studied in field experiments in 1980, 1981 and 1982.Yields varied between 5000 and 8000 kg dry matter of kernels per ha. The effect of the saprophytic mycoflora on yield was determined in different treatments: A) no control measures against cereal aphids and saprophytic and necrotrophic fungi, B) no control of cereal aphids, control of saprophytic and necrotrophic fungi, C) control of cereal aphids and control of saprophytic and necrotrophic fungi, D) control of cereal aphids and stimulation of saprophytic mycoflora and E) control of cereal aphids, no control of saprophytic and necrotrophic fungi nor stimulation of saprophytic mycoflora.Considerable differences in top densities of saprophytic mycoflora (10 times as large in A and D as in B and C) were determined. The consequences of these differences for the growth and productivity of wheat were minor. A negative effect of saprophytic mycoflora on the yield could not be detected in 1981 and 1982, whereas a small positive significant effect was found in 1980. This stimulation may have been due to competition between necrotrophic fungal pathogens and saprophytic mycoflora. As a result of favourable weather conditions necrotrophic fungal pathogens were very numerous in 1980 and could form an important yield reducing factor. Yield levels may effect the importance of the necrotrophic and saprophytic mycoflora as yield reducing factors. Additionally, in the presence of aphid honeydew captafol was found to be relatively ineffective against saprophytic fungi.     

Relationship Between Production of the Phytotoxin Prehelminthosporol and Virulence in Isolates of the Plant Pathogenic Fungus Bipolaris sorokiniana

A gas chromatographic method was developed to quantify the phytotoxin prehelminthosporol, which is a sesquiterpene metabolite of the plant pathogen Bipolaris sorokiniana. The toxin was extracted from mycelium or culture filtrates, pre-cleaned using solid phase extraction, and analyzed by gas chromatography as a trimethylsilyl-derivative. The detection limit of the method was 5ngl^–1 (signal to noise ratio 4:1) which corresponds to ca. 15ng prehelminthosporol per mg dry weight of mycelium or 15ng prehelminthosporol per ml culture filtrate. The total amount of prehelminthosporol (mycelium plus culture filtrate) increased with cultivation time when examined in six isolates of B. sorokiniana after 6, 9, 12 and 15 days of incubation. The screening experiment of 17 isolates for prehelminthosporol production after 8 days of incubation revealed significant differences in the toxin production between the isolates. The isolates with low toxin production had lower virulence towards barley roots compared to those with higher production of the toxin. However, the virulence did not increase with prehelminthosporol level among the high producing isolates. Prehelminthosporol was also analyzed in a number of related Bipolaris and Drechslera species. In addition to B. sorokiniana, three out of six Bipolaris species (B. setariae, B. zeicola, B. victoriae) produced prehelminthosporol, which indicates that ability to produce prehelminthosporol is conserved among closely-related Bipolaris species.     

Effect of botanical insecticides and bacterial toxins on the gut enzyme of the rice leaffolderCnaphalocrocis medinalis

The effect of botanical insecticides and bacterial toxins on gut enzyme activity of larvae of the rice leaffolderCnaphalocrocis medinalis (Guenée) (Insecta: Lepidoptera: Pyralidae) was investigated. Gut enzyme activities were affected by botanical insecticides and bacterial toxin individually and in combination. When fed a diet of rice leaves treated with botanical insecticides and bacterial toxins, in bioassays the activities of gut tissue enzymes — acid phosphatases (ACP), alkaline phosphatases (ALP) and adenosine triphosphatases (ATPase) — of rice leaffolder larvae were affected. When combined, the effect was more severe at a low concentration. Larvae that were chronically exposed to botanical insecticides and bacterial toxins showed a reduction in weight (59–89%) and exhibited a significant reduction in ACP, ALP and ATPase activities. The combination ofBacillus thuringiensis kurstaki and botanical insecticides caused a decrease of twofold in enzyme activity even at reduced concentration. A synergistic effect was found when botanical insecticides and bacterial toxins were combined at low doses. These effects were most pronounced in early instars. Clear dose-response relationships were established with respect to enzyme activity. In conclusion: (i) biopesticides are relatively safe and biodegradable; (ii) a synergistic effect of botanical insecticides and bacterial toxins was found; (iii) less expensive, readily available and naturally occurring biopesticides could be an alternative for organic and inorganic pesticides in controlling RLF. http://www.phytoparasitica.org posting Sept. 28, 2004.