酥梨采后灰霉病生防菌株的鉴定及抑菌作用

以微生物拮抗病原菌是防治病害安全高效的可行手段。通过对果实表面微生物进行筛选鉴定,以期得到一株可以有效抑制灰霉病的生物防治菌株。对拮抗菌株H-1进行形态学特征、生理生化特性分析,结合16S rDNA序列分析和gyrB 基因序列分析构建系统发育树;采用平板对峙法结合果实伤口试验考察拮抗菌H-1在体外及梨果表面的抑菌作用。结果表明：经鉴定H-I菌株为贝莱斯芽孢杆菌（Bacillus velezensis）;B. velezensis H-1在体外条件下可显著抑制灰葡萄孢霉（Botrytis cinerea）、细极链格孢（Alternaria tenuissima）和串珠镰孢菌（Fusarium verticillioides）的菌丝生长,其中对灰葡萄孢霉菌丝的抑制作用最强;果实伤口试验表明,1×1011 CFU/mL的B. velezensis H-1可完全抑制梨果表面灰霉菌生长。由此可见,B. velezensis H-1可以有效抑制梨果采后灰霉病的发生。     

灌水器注塑模浇注系统计算机辅助设计

根据灌水器注塑模非平衡浇注系统的特点,给出了非平衡浇注系统的流动平衡数学模型,通过基于Pro／toolkit的二次开发,在Pro／E软件平台上实现了非平衡浇注系统的流动平衡计算及其自动生成,避免了反复的试模与修改,提高了设计效率,降低了生产成本。     

浅析发酵乳霉菌零星污染来源及控制方法

霉菌在自然环境中普遍存在,而且以孢子形态随空气、水等媒介进行扩散.对食品原辅料及生产环境均可造成污染,是造成发酵乳变质的主要原因.发酵乳作为保质期较短且需冷链储运、销售的产品,零星的霉菌污染不会引起食品安全问题,但由于部分销售终端及三四线市场冷链运输缺失,造成霉菌生长,发酵乳呈现明显霉斑,导致消费者体验差,给企业品牌造...     

反刍动物微生态制剂高活性菌种的筛选与比较

该研究的目的是对8株酵母菌和4株霉菌生物学活性进行比较研究,筛选出优良高活性菌株。方法:通过对8株酵母菌的生物量、粗蛋白含量、活菌数、发酵香味及4株霉菌生物量和产酶能力等指标的测定,筛选优良菌株作为试验基础菌种。结果表明,酿酒酵母BC和BD、产朊假丝酵母BY、热带假丝酵母BR和黑曲霉H3,以其优良的生产性能被选为反刍动物微生态制剂试验用菌种。     

双胍盐对柑桔青霉病防治效果试验

两年的抑菌、刻伤接种和果实贮藏试验表明,双胍盐对柑桔青霉病的防治效果与伊迈唑相接近,可作为苯并咪唑类的替换药剂。     

设施栽培条件下月季灰霉病预测模型的建立及应用

为有效防治月季灰霉病发生,保障切花产品采后品质,以‘粉蝴蝶’(‘Vuvuzela’)和‘雪山’(‘Avalanche’)为试验材料,实地调查设施内灰霉病发病情况,监测温室内温湿度,获取当地降雨量等气象资料,构建了月季切花设施生产灰霉病预测模型,并利用这一模型进行灰霉病防治的实际指导。结果表明：1)‘粉蝴蝶’‘雪山’的灰霉病病情指数与设施内的均温和均湿呈线性相关,据此建立灰霉病预测模型,Y=4.761-0.332X₁+4.930X₂+0.015X₃;这一预测模型经设施内实测验证,平均绝对误差(MAE)=0.20,平均绝对百分误差(MAPE)=0.31,表明可有效预测7日内设施条件下月季切花灰霉病发病情况。2)‘粉蝴蝶’‘雪山’在贮藏和瓶插期的灰霉病发病率与栽培中病情指数预测值呈正相关。当病情指数为Y=0.33的低预测值时,切花产品在模拟运输1 d+冷库贮藏5 d后,发病率为5.0%;当病情指数为Y=2.09的高预测值时,切花产品在相同处理后发病率可达35.0%。3)基于预测模型进行病害爆发前3 d喷药的早期防治处理,采收当...     

An inhibitor of polyamine biosynthesis — Difluoromethylornithine — and the polyamine spermidine for the control of gray mold(Botrytis Cinerea)

Difluoromethylornithine (DFMO) — an inhibitor of polyamine biosynthesis, and the polyamine spermidine (Spd) reduced gray mold of tomato, pepper, eggplant, bean andSenecio sp. leaves, and of rose petals by 37–88% when applied at 0.1–1.0 mM each. Higher doses did not result in better control. The disease was also reduced significantly on tomato fruits by 1.0 inM DFMO and by 0.1–1.0 mM Spd, and on cucumber fruits by 0.1–1.0 mM of both compounds, but not on grape berries. The combination of 0.2 mM DFMO with 1.0 mM Spd controlled gray mold ofSenecio sp. and tomato leaves additively better than either treatment alone, whereas this effect was not observed in leaves of lettuce and pepper. Ethylene production was reduced significantly by Spd applied to leaves of tomato and pepper, but not by DFMO. Linear growth and germination of the fungus were affected by lower concentrations of DFMO (ED50 0.12–0.97 and 1.4, respectively) as compared with Spd. Spermidine and DFMO controlled white mold(Sclerotinia sclerotiorum) as effectively as did the fungicide benomyl. Contribution from the Agricultural Research Organization. No. 3195-E, 1991 series.     

橡胶木防霉防蓝变药剂的现场试验

现场试验的结果表明，F1/F2混剂处理的橡胶木圆盘、单板的防霉及防蓝变效果较F2及五氯酚钠要好。F1/F2及五氯酚钠各制剂处理的板材基本上无霉菌感染及蓝变。在真空加压试验中，0.02?可保持橡胶木板材在气干过程中12天基本不霉变及蓝变，但对白霉的防治效果较差；0.0094?与0.018?混合剂可保持像胶木板材气干时15天不长霉或蓝变，增加F1/F2的浓度可能会在气干时保持更长的时间。     

百菌清制剂防霉效果的初步研究

以杨木、马尾松为试材，百菌清制剂Ｆ１及Ｆ２防治青霉、黑曲霉霉菌的效果进行了室内试验研究。结果表明百菌清制剂Ｆ２防治杨木、马尾松试块的青霉、黑曲霉的效果与五氯酚钠相当，甚至较ＮａＰＣＰ好。     

A comparison of the response of different citrus fruit cultivars to storage temperature

A comparison was made of the response to storage temperatures (0–17°C) of grapefruit ‘Shamouti’ and ‘Valencia’ oranges, and lemon fruit. There was no chilling injury (CI) and the incidence of rot was relatively low at 12°C or higher for all cultivars. At low storage temperatures, however, pitting and subsequent rot development in grapefruit and in ‘Shamouti’ and ‘Valencia’ oranges were highest at 6°C, while in lemon the incidence of these disorders rose with the decrease in storage temperature, and was highest at 2°C. Grapefruit and ‘Shamouti’ oranges exhibited the highest susceptibility to CI, lemon showed an intermediate susceptibility, and ‘Valencia’ orange a very low one. In grapefruit, severe peel pittings that developed in cold storage were covered by mold rots during cold storage and shelf-life, but in ‘Valencia’ and particularly in ‘Shamouti’ oranges the incidence of decay during cold storage was low. During shelf-life, a pronounced CI-induced increase in the incidence of mold rots was evident. This breakdown during shelf-life may be associated with microscopic peel injuries which are formed during cold storage and covered by mold rots during shelf-life. Increased susceptibility of the cultivar to CI could be correlated with an increase in ethanol content at low temperatures.