赞米尔等药剂对小麦赤霉病的防效

小麦赤霉病在长江中下游地区危害日益严重,小麦赤霉病的发生不仅造成小麦产量严重下降,而且籽粒带毒危及人畜健康。随着单一化学农药的长期使用,小麦赤霉病菌的抗药性日益增强,选用新型药剂是提高药效、延缓抗药性的有效策略之一。试验结果表明:戊唑·咪鲜胺与氰烯·戊唑醇病指防效没有显著差异,防效均在80%以上,该结果为小麦赤霉病的有效防治推广提供了依据。     

观赏鱼水霉病中草药治疗药物的筛选

为了筛选并且比较五倍子、川楝子、苦参、黄连、大黄,五种中草药对水霉菌的抑制效果,以五倍子、川楝子、苦参、黄连、大黄为药材分别熬制成1g/mL药汁,通过对水霉菌的纯化和接种制得水霉菌,然后通过离心得到孢子液,采用倍比稀释调节到适宜浓度,并通过琼脂平板培养法筛选治疗效果较好的中草药。两组试验的结果表明五倍子抑菌圈在3.7×105cfu/m L的孢子浓度下分别为15.1mm和17.8mm黄连抑菌圈在同样浓度下分别为8.1mm和13.0mm苦参、大黄、川楝子无抑菌圈,得出五倍子对水霉菌的抑菌效果最好;其次是黄连,并且黄连对某种青霉也有抑菌作用,其余中草药对水霉菌抑菌效果十分微弱。     

茶籽粕中抑菌活性物质的提取及抑菌效果研究

采用琼脂扩散法研究了茶籽粕提取物中醇提部分对常见的革兰氏阳性菌和革兰氏阴性菌、部分霉菌的抑菌活性,研究其在不同温度、pH值和光照条件下的抑菌效果。结果表明:茶籽粕提取物对大肠杆菌、金黄色葡萄球菌、沙门氏菌、苏云金杆菌、黑曲霉和黄曲霉都有显著的抑制效果,最低抑菌浓度30～500μg/mL之间,且在120℃以内,酸性环境下以及不同光照下都具有良好的稳定性。     

几种药剂对水稻恶苗病的防效试验简报

药剂浸种是防治水稻恶苗病的关键措施。为了解浸种药剂在当前生产上对水稻恶苗病防治效果,特选择4种药剂开展水稻恶苗病防效试验。结果表明,25%氰烯菌酯悬浮剂防效最好,苗期与大田期防效分别为93.44%、91.74%;4种药剂均具有较好防效,苗期防效在90%以上,大田期防效在85%以上,药剂之间差异不显著;按推荐剂量使用对水稻发芽及生长均安全。因此,生产上该4种药剂作浸种剂可推广应用,并可相互交替使用,从而避免长期使用单一药剂产生抗性影响防效。     

红棕杜鹃(原变种)叶提取物抑菌活性的研究

本试验以红棕杜鹃(原变种)叶为原料,用有机溶剂95%乙醇、石油醚、乙酸乙酯、正丁醇初步提取红棕杜鹃(原变种)叶的活性成分,测定其对大肠杆菌和金黄色葡萄球菌的抑菌活性。试验结果表明:三种粗提液中乙酸乙酯粗提液对大肠杆菌和金黄色葡萄球菌的抑菌效果最好,95%乙醇粗提液对大肠杆菌和金黄色葡萄球菌的抑菌效果次之,石油醚粗提液对大肠杆菌和金黄色葡萄球菌的抑菌效果最弱。三种萃取相中乙酸乙酯萃取相对大肠杆菌和金黄色葡萄球菌抑菌效果最好,石油醚萃取相对大肠杆菌和金黄色葡萄球菌的抑菌效果稍弱,正丁醇萃取相对大肠杆菌和金黄色葡萄球菌的抑菌效果最差。此试验说明红棕杜鹃(原变种)叶含有对大肠杆菌和金黄色葡萄球菌抑菌作用的成分,为植物源性抗菌药物的开发提供了一定的理论基础。     

黄金梨CA和MAP贮藏保鲜试验

研究了黄金梨不同浓度1-MCP处理后,CA和MAP贮藏条件对果实的防褐保鲜效果.结果表明,3.0%O_2+0.5%CO_2组合贮藏黄金梨防褐保鲜效果较好,可保持果实较高硬度,完全抑制黑皮,明显降低果心褐变指数;在CA贮藏条件下使用1.0 μL/L 1-MCP易对果实产生CO_2伤害.挽口和薄袋扎口贮藏结合0.5 μL/L 1-MCP处理能获得良好的防褐保鲜效果;在无1-MCP处理条件下,厚袋扎口处理能起到良好的自发气调作用,而1-MCP处理的果实则产生不同程度的CO_2伤害.     

不同种衣剂防治水稻恶苗病效果分析

选取不同药剂,选用不同种子处理方法进行水稻恶苗病防治试验,调查并比较不同处理的田间防效。结果表明,防效最好的为福美双·多菌灵包衣+甲霜·种菌唑浸种处理,防效为97.94%;其次为种衣剂福美双·多菌灵+精甲·咯·嘧菌混配处理,防效为95.88%;单独使用11%精甲·咯·嘧菌悬浮种衣剂对水稻恶苗病的防效较差,显著低于其他处理。     

壳聚糖添加纳米碳酸钙助剂对鲜切山药品质的影

为了探索纳米碳酸钙助剂对鲜切山药保鲜效果的影响,研究了壳聚糖添加纳米碳酸钙助剂对鲜切山药在10℃下品质的影响.结果表明,壳聚糖添加纳米碳酸钙助剂处理后鲜切山药的总酸度、Vc含量和L值分别比单独使用壳聚糖高10.5%、8.4%和6.9%;失重率和总酚含量分别比单独使用壳聚糖低9.2%和8.3%.壳聚糖添加纳米碳酸钙助剂可显著抑制多酚氧化酶和过氧化物酶活性,延缓果实褐变,延长货架期.添加纳米碳酸钙助剂可显著提高壳聚糖对鲜切山药的保鲜效果.     

微喷带随水施用除草剂除草效果及均匀度研究

为分析微喷带水药一体灌溉时药品施用效果和均匀度,在武威开展了大田微喷带随水施用除草剂试验。以常用?32斜5孔微喷带为灌水施药设备,长度40 m,在正常工作压力(55 kPa)和总药量(1.522 5 kg/hm~2)下,通过调节施药器内药液浓度(试验A区1.5、B区2.0、C区3.0 g/L)对微喷带随水施用除草剂的大田除草效果和施药均匀度进行分析。结果表明:试验A、B、C区在垂直微喷带方向,杂草株防效呈先增大后变小的趋势,与微喷带水量分布规律一致;在总药量相同的情况下,在微喷带3 m位置,A1与B1、C1达到显著差异(P0.05),20 m位置不同浓度之间差异不显著,37 m位置A1、B1与C1之间存在显著差异(P0.05)。沿微喷带方向杂草株防效均匀度逐渐降低,垂直微喷带均匀度先变大后变小。试验C区杂草防效均匀度明显低于A、B区,A、B区均匀度Cu均在0.98附近,C区Cu最大值为0.98,最小值仅为0.78,差异显著。基于提高微喷带施药的均匀度,兼顾杂草防效,使用微喷带水药一体施用该除草剂时浓度为2.0 g/L效果较好。     

高压静电场处理番茄贮藏保鲜试验

以番茄果实为材料,利用30,60,90kV/m高压静电场对番茄果实进行20,40,60min预处理,然后置于16℃左右的室温条件下贮藏,定期测定番茄的Vc含量、酸度、质量损失率等保鲜性能指标,研究了不同剂量的高压静电场对番茄的保鲜效果.试验结果表明,高压静电场处理能够很好地抑制番茄质量的损失和番茄果实Vc含量、酸度的变化,延迟了番茄果实腐败的发生.另外,利用60kV/m高压静电场处理60min,其果实Vc含量、果实质量损失率以及酸度的变化均小于其他处理,保鲜效果最好.     

Minimizing salt in drain water by irrigation management — Arizona field studies with citrus

A field experiment was conducted for 5 years in the Wellton-Mohawk Irrigation and Drainage District of southwest Arizona to investigate the potential for reducing the salt load in irrigation return flow by decreased leaching in citrus. Leaching treatments of 5, 10, and 20%, replicated nine times, were established on mature Valencia orange trees (Citrus sinensis L.) and compared with conventional flood irrigation management.The annual evapotranspiration was found to be about 1470 mm. The leaching fractions, determined indirectly by several techniques, were close to those intended. The leaching fraction for the flood check was 0.47. During the first 4 years, the leaching treatments had no observable influence on fruit yield or quality or on tree growth. During the last year of the study, however, the yield of the 5% leaching treatment was significantly lower than the other treatments. Thus, with some uncertainty, the leaching requirement for Valencia orange irrigated with Colorado River water exceeds 5% but is less than 20%.Results verify that water applications could be reduced substantially below typical commercial practice without loss of crop yield. At the conclusion of the experiment reducing the leaching fraction to 0.20 for the 3000 ha of citrus in the District would reduce the salt load in the irrigation return flow by 127000 Mg annually. After steady state conditions are reached at 20% leaching the annual reduction would be 42500 Mg.     

柑橘类果汁中柚皮苷的分析

柚皮苷是柑橘汁中主要的苦味物质之一,其含量高低影响果汁的色泽、口味、稳定性等.通过分光光度法分析了9种柑橘类果汁中柚皮苷的含量,研究结果表明：胡柚汁中柚皮苷含量最高,为3.018 g/L,芦柑汁中柚皮苷含量最低,为0.310 g/L.在此基础上,用数学统计的方法对9种柑橘类果汁中柚皮苷含量差异性分析表明：脐橙汁与象山橘汁,椪柑汁与蜜柚汁柚皮苷含量无差别;椪柑汁比芦柑汁高,蜜柚汁比芦柑汁高,差异显著;其余种类果汁间柚皮苷含量均有极显著差异.     

沙棘不同器官提取物对小鼠实体瘤的抗癌药效学研究

用沙棘叶、果、茎、根的提取物和籽油,对患H22和EAC的实体瘤小鼠进行灌胃实验。结果表明,沙棘不同器官提取物和籽油都具有显著的抑瘤效果。在15个不同处理剂量组中,有10个剂量组的抑瘤率都超过了30%,占到处理总数的66.6%。沙棘不同器官提取物对实体瘤小鼠的抑瘤率表现为:叶>果>油>茎>根,叶和果的高剂量组抑瘤率分别为58%和46.7%。沙棘提取物抑瘤的主要原因是增强了实体瘤小鼠的免疫功能,提高了脾指数和胸腺指数,且胸腺指数效果大于脾指数的。沙棘提取物有利于调节患病小鼠的脏器活力。     

Minimizing salt in drain water by irrigation management: Design and initial results of Arizona field studies

Two field experiments were established in the Wellton-Mohawk Irrigation and Drainage District of southwestern Arizona to test the feasibility of decreasing the salt load in drainage water by reduced leaching. Results are given for the initial 2 years of the test for Valencia orange trees (Citrus sinensis L.) and the first year for alfalfa (Medicago sativa L., cv. Hayden).The water application data, substantiated by salinity sensor readings and measures of soil chloride, indicate that the annual evapotranspiration of Valencia orange is approximately 1375 mm on a total area basis. After 2 years, fruit yield and quality and tree growth are not significantly different from flood-irrigated trees that receive 40% more water. If these results persist, the salt load from citrus in the district could be reduced 40 000 Mg annually by reduced leaching. More importantly, because of the salinity of the groundwater pumped for water table control, the salt load exported from the district could be reduced initially by 130 000 Mg annually.Results indicate that the alfalfa experiment was underirrigated the first year and evapotranspiration is about 1950 mm annually. Comparisons indicate that the level basin flood irrigated check yielded 20% more than the experiment and had about 10% leaching, an efficiency that can probably not be improved.     

自然场景下树上柑橘实时识别技术

采用G-B色差分量,通过Otsu自适应阈值分割算法分割成熟柑橘图像,采用基于距离变换的分水岭分割将遮挡、重叠柑橘逐个分开,利用凸包算法修复遮挡区域,设定圆度阈值去除误分割区域,然后提取柑橘轮廓,并运用基于Tukey权重函数的最小二乘圆拟合特征圆,提取了柑橘的中心坐标及半径.对87幅图像中592个柑橘进行了识别试验,总体识别率达87.2%,遮挡或重叠柑橘识别率均超过80%.     

富锌蛹虫草菌丝体不同溶剂浸提物的体外抗氧化能力

以富锌蛹虫草菌丝体水、乙醇、乙酸乙酯提取物为研究材料,对其体外清除O2-自由基、羟自由基和DPPH有机自由基的抗氧化能力进行了测定。结果显示:提取物的浓度越高,对O2-自由基、羟自由基、DPPH的清除率越高。不同溶剂提取物对不同自由基清除率作用不同,当提取物浓度为90 mg/mL时,水提取物对O2-自由基清除率最高可达66.93%,乙醇提取物对羟自由基清除率最高为87.59%,乙酸乙酯提取物对DPPH清除率最高达到100%。      

枝上柑橘果实深度球截线识别方法

针对柑橘果、叶、枝对象具有球体、片体和细柱体不同的三维几何特征,提出一种识别柑橘果实的深度球截线方法。首先提出了球形果实特征提取的深度球截线方法的基本原理和关键参数,进而分别针对枝上果、叶孤立和贴碰区域提出了孤立果实的特征提取算法和贴碰果实的特征提取算法,得到了复杂枝环境下的深度数据处理与果实识别策略,并综合根据Intel Real Sense F200型深度传感器参数、柑橘果实尺寸、近景探测范围、数据预处理与特征提取需要完成了深度球截线方法的参数确定。大量室内试验结果表明,深度球截线方法对孤立果实提取的平均成功率为97.8%,贴碰区域内果实提取的平均成功率为76%,而复杂枝环境的果实提取综合成功率为63.8%。该深度球截线的识别方法仅利用有限的深度数据点,在保证原始数据精度的同时降低了运算量和果实特征提取复杂性,能有效应对果叶遮挡问题,实现对贴碰果叶的有效区分,对柑橘果实具有良好的适应性,为采摘机器人在复杂环境下的果实识别与定位提供了新的技术思路。     

Scheduling deficit irrigation of citrus trees with maximum daily trunk shrinkage

The feasibility of scheduling deficit irrigation using maximum daily trunk shrinkage (MDS) was evaluated during two consecutive seasons in a citrus orchard planted with mature ‘Clementina de Nules’ trees, in Valencia, Spain. Results showed that MDS in well irrigated trees varied largely according to the environmental conditions (higher correlation was obtained with global radiation), and therefore, the absolute values of MDS cannot be employed as the only variable to schedule irrigation. To avoid the effects of the climatic conditions we scheduled deficit irrigation using the MDS ratio, which is the MDS of any treatment related to the MDS of a control, well irrigated, treatment located in the same plot. We explored the feasibility of scheduling irrigation based on the MDS ratio in a deficit irrigated treatment, where water was applied as necessary, from July until mid October, in order to maintain the MDS values at 125% of that of the control treatment. Despite the large variability observed in the MDS measurements in both years no significant reduction in yield and fruit weight was observed in the deficit irrigated treatment compared with the control, allowing seasonal water saving between 18 and 12%.     

Distribution of rainfall and soil moisture content in the soil profile under citrus tree canopy and at the dripline

The plant canopy intercepts rain and thus can alter the distribution of water under the canopy as compared to that along the dripline. The effects of a citrus (Citrus sinensis L. Osbeck) tree (25-year-old, Valencia orange) canopy on the distribution of rainfall and soil moisture content within the soil profile either along the dripline (D) or under the canopy near the trunk (inner side; I), and midway between I and Dripline (M) were evaluated, on the east and west sides of trees planted along north-south rows. Results of eleven storm events in 1995 (mean of east and west sides) revealed that the amounts of precipitation at the D, M, and I positions were 97–140, 47–94, and 52–79% of the incident rainfall, respectively. Thus, canopy interception of incident rainfall was quite appreciable. The soil moisture content was greater along the dripline compared to that at the M and I positions, particularly in the deeper (≥60 cm) soil profile. The water flux was significantly greater at the dripline than under the canopy indicating a greater leaching potential of soil-applied fertilizers and other chemicals when placed along the dripline. A substantial reduction in the rainfall and water flux under the canopy as a result of canopy interception suggests that application of fertilizer and chemicals under the canopy could minimize leaching losses. Received: 10 November 1997     

基于色调分形维数的柑橘糖度和有效酸度检

研究了宫川温州蜜柑糖度及有效酸度的机器视觉检测技术及影响检测精度的因素.对机器视觉系统采集的柑橘图像进行图像裁切、亮度法去图像背景和RGB空间至HSI空间的转换,将柑橘色调范围分割为0°～20°、20°～40°、40°～60°、60°～80°、80°～100°和100°～120°共6个区域,提取各区域色调分形维数,以此作为BP神经网络输入,无损检测宫川温州蜜柑糖度及有效酸度.167个测试样本的检测结果表明:在±1.5°Brix精度范围内糖度正确识别率为66.6175%,在±0.5精度范围内有效酸度正确识别率为73.9275%.宫川温州蜜柑糖度及有效酸度与果皮色调分形维数之间具有相关性,可用机器视觉检测其糖度及有效酸度.