Effect of antagonistic<Emphasis Type="Italic">Fusarium</Emphasis> spp. and of different commercial biofungicide formulations on Fusarium wilt of lettuce

Five experimental trials were carried out to test different biological control agents against Fusarium wilt of lettuce, cause byFusarium oxysporum f.sp.lactucae. In the presence of a very high disease incidence, the best results in terms of disease control as well as increased growth response were shown byTrichoderma harzianum T 22 (RootShield), which, at 3 gl ⁻¹ of substrate, provided very consistent results.F. oxysporum IF 23 gave good disease control but in two out of five trials reduced the biomass produced. Less consistent, but still significant results were provided byF oxysporium MSA 25, at 3 gl ⁻¹ of substrate, and byTrichoderma viride TV 1. The twoF. oxysporum agents Fo 251/2 and Fo 47 and the mixture ofT. harzianum + T. viride (Remedier) partially reduced disease incidence but were less effective than the above mentioned. Less interesting results were offered byStreptomyces griseoviridis (Mycostop). The results obtained show that biological control can play a role in the management of Fusarium wilt of lettuce.     

The hymenopteran parasitoids of some elm bark beetles in Serbia

The parasitoids of the elm bark beetlesScolytus ensifer, S. kirschi, S. multistriatus, S. pygmaeus andPteleobius vittatus were studied in ten localities in Serbia. Eleven species of parasitoids ofS. ensifer, 10 ofS. kirschi, 13 ofS. multistriatus, 12 ofS. pygmaeus, and four ofP. vittatus were found. The most abundant wereEcphylus silesiacus, Dendrosoter protuberans, Cheiropachus quadrum andRhaphitelus maculatus. Acrocormus semifasciatus, Cerocephala eccoptogastri, Mesopolobus typographi andDoryctes pomarius were found in some samples. http://www.phytoparasitica.org posting May 4, 2007     

额济纳绿洲柽柳灌丛辐射特征与热量平衡研究

根据黑河下游额济纳绿洲柽柳灌丛波文比-能量平衡法的实测资料,分析了该地区的辐射特征,研究了热量平衡各分量的变化特征及热量平衡规律。在绿洲内部,其太阳辐射、净辐射具有明显的日进程和季节变化规律;太阳辐射月总量最大值(2133325.0kW.m-2)出现在6月份,最小值(133325.0kW.m-2)出现在10月份;在柽柳灌丛生态系统的热量平衡中潜热通量占能量支出量的62.85%,感热通量占32.85%,土壤热通量占4.44%。在日变化中,潜热在上午大于感热,在下午,由于湍流加剧,感热交换大于潜热。     

晋南地区黄瓜、黑籽南瓜死秧的病原菌鉴定及品种抗性研究

经分离、培养对不同菌种培养性状的观察,确定了侵染黄瓜、黑籽南瓜造成死秧的镰刀菌主要为尖镰孢菌黄瓜专化型、尖镰孢菌西瓜专化型、串珠镰刀菌和腐皮镰孢菌4种。经致病性测定,4种镰刀菌均能侵染黄瓜,引起发病造成死秧,可分为强致病类型和中强致病类型。经抗病性鉴定,黑籽南瓜种子只有南瓜4号为耐病品种;黄瓜种子也只有津优31号为耐病品种。     

植物生长调节剂在李上的研究应用

综述了植物生长调节剂在推迟李（Prunus spp.)花期、提高李座果率、疏花疏果以及控制李树旺长等方面的研究应用情况。     

辽宁省野生羊肚菌资源调查与遗传多样性分析

为了调查辽宁省的羊肚菌资源,了解其产地环境及种属的关系,探寻羊肚菌在辽宁省发生的适合条件,对辽宁省7市16个羊肚菌发生地开展了资源调查,共采集到羊肚菌样本53份.采用ITS和多基因系谱一致性系统发育种识别法(GCPSR),对采集到的羊肚菌样本进行鉴定和遗传多样性分析.结果表明,采集的羊肚菌样本被鉴定为5种,即Morch...     

Study on Coccidiosis of Scavenging Indigenous Chickens in Central Ethiopia

An investigation was made into coccidiosis of 190 scavenging indigenous chickens between September 2000 and April 2001 in three selected agroclimatic zones, in central Ethiopia. This was done through clinical, postmortem and microscopic examinations. Data were processed by chi-square and Mantel-Haenzel test. The study indicated that 25.8% (49/190) of the chickens were infected with coccidiosis and found to harbour one to four different species of Eimeria. Of these infected chickens, 30 (15.8%) and 19 (10.0%) were positive for clinical and sub-clinical coccidiosis, respectively. There was a significant altitude difference (chi2 = 14.7, p <0.001) in coccidiosis prevalence: 42.2% in chickens from highland region followed by 21.5% in mid-altitude and 13.1% in low-altitude areas. When quantified, the prevalence of coccidiosis was 2.66 and 4.83 times higher in the high-altitude than in mid-altitude (odds ratio, OR = 2.66, p<0.05) and low-altitude (OR = 4.83, p<0.001) chickens. The pathogenic Eimeria species responsible for clinical coccidiosis were E. necatrix, E. acervulina, E. maxima and E. tenella. With increasing demand for poultry products in developing countries, knowledge of production constraints in traditional management practices could help devise control strategies for constraints on backyard poultry production systems.     

A comparison of two dose levels of antibiotics for intramammary treatment of clinical mastitis in cows

A clinical trial was conducted in Nordre Valdres, Norway, to examine the effect of a low-level vs. a high-level intramammary antibiotic treatment of clinical mastitis. It was also of interest to identify significant risk factors and to estimate the probability of no recovery for given defined levels of risk factors. Quarter milk samples from 166 cows with clinical mastitis were examined before and after treatment, at 3 weeks interval. The two treatment levels did not differ significantly with respect to recovery rate. The probability of no recovery could be estimated by using information on the severity of general clinical signs, lactation number, bacteriological findings, and quarter location.     

Understanding fishing‐induced extinctions in the Amazon

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