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通过对河南春水镇农业保险的调查背景描述以及对河南春水镇农户进行走访和问卷调查的基础上,分析农户对农业保险的认知度及参与意愿,研究河南春水镇农户对农业保险的认知度以及其参加农业保险的意愿,并得出调查研究结论,最终提出应加大农业保险的宣传、转变农户思想观念以及增加农户农业收入的对策与建议. 相似文献
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建立清真牛羊肉溯源系统可以对肉品生产运销过程中的危害物及穆斯林禁忌物进行有效控制,提高肉品质量安全。首先阐述了QRCode二维码的基本特性,设计了清真牛羊肉溯源系统的总体框架,实现了溯源系统QR码的生成,并利用DES算法对QR码进行加密,最后完成了QR码识别和溯源查询功能。建立基于QR码的清真肉品溯源系统,一方面保障了消费者对产品的知情权,另一方面提高了内品的安全性与可靠性。 相似文献
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Edna Sharon Ilan Chet Ada Viterbo Meira Bar-Eyal Harel Nagan Gary J. Samuels Yitzhak Spiegel 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(3):247-258
Trichoderma (T.
asperellum-203, 44 and GH11; T. atroviride-IMI 206040 and T. harzianum-248) parasitism on Meloidogyne javanica life stages was examined in vitro. Conidium attachment and parasitism differed beween the fungi. Egg masses, their derived
eggs and second-stage juveniles (J2) were parasitized by Trichoderma
asperellum-203, 44, and T. atroviride following conidium attachment. Trichoderma
asperellum-GH11 attached to the nematodes but exhibited reduced penetration, whereas growth of T. harzianum-248 attached to egg masses was inhibited. Only a few conidia of the different fungi were attached to eggs and J2s without
gelatinous matrix; the eggs were penetrated and parasitized by few hyphae, while J2s were rarely parasitized by the fungi.
The gelatinous matrix specifically induced J2 immobilization by T.
asperellum-203, 44 and T. atroviride metabolites that immobilized the J2s. A constitutive-GFP-expressing T. asperellum-203 construct was used to visualize fungal penetration of the nematodes. Scanning electron microscopy revealed the formation
of coiling and appressorium-like structures upon attachment and parasitism by T. asperellum-203 and T. atroviride. Gelatinous matrix agglutinated T. asperellum-203 and T. atroviride conidia, a process that was Ca2+-dependent. Conidium agglutination was inhibited by carbohydrates, including fucose, as was conidium attachment to the nematodes.
All but T. harzianum could grow on the gelatinous matrix, which enhanced conidium germination. A biomimetic system based on gelatinous-matrix-coated
nylon fibers demonstrated the role of the matrix in parasitism: T. asperellum-203 and T. atroviride conidia attached specifically to the gelatinous-matrix-coated fibers and parasitic growth patterns, such as coiling, branching
and appressoria-like structures, were induced in both fungi, similarly to those observed during nematode parasitism. All Trichoderma isolates exhibited nematode biocontrol activity in pot experiments with tomato plants. Parasitic interactions were demonstrated
in planta: females and egg masses dissected from tomato roots grown in T. asperellum-203-treated soil were examined and found to be parasitized by the fungus. This study demonstrates biocontrol activities of
Trichoderma isolates and their parasitic capabilities on M. javanica, elucidating the importance of the gelatinous matrix in the fungal parasitism. 相似文献
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9种胁迫条件下棉花叶片光谱特征及其识别研究 总被引:1,自引:0,他引:1
对不同胁迫条件下棉叶光谱特征进行比较研究,可为棉花胁迫类型识别提供理论依据。以田间获取的9种胁迫棉叶为材料,对9种胁迫叶片进行光谱测试,分析各自光谱特征差异,对其进行定性定量的识别。结果表明:黄萎病、枯萎病、干旱、缺氮、红蜘蛛和角斑病棉叶光谱反射率形状和大小在全波段均发生了较大变化,蚜虫、冻害和盐害均变化较小。9种胁迫棉叶的光谱"绿峰"和"红边"均具有"单峰"现象,其中黄萎病、干旱、缺氮、枯萎病、红蜘蛛和角斑病2个"单峰"峰值均减小,"单峰"位置均发生"蓝移",而蚜虫、冻害和盐害基本不变。蚜虫棉叶的吸收波段位置、吸收深度、吸收面积略微增加,其他胁迫均减小,蚜虫棉叶吸收宽度略微减小,冻害棉叶吸收宽度基本不变,盐害棉叶吸收宽度先增后减,其他胁迫棉叶的吸收宽度均增加。不同胁迫棉叶的14个光谱特征参数表现出一定的规律,建立相应的判别式可有效对不同胁迫棉叶进行准确识别。因此,利用光谱技术进行棉花叶片不同胁迫诊断是可行的。 相似文献
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基于数字图像的水果分形维数特征 总被引:1,自引:0,他引:1
温芝元 《湖南农业大学学报(自然科学版)》2010,36(4):478-482
为了定量描述仿球形水果表面轮廓间的差异,用周长-面积法研究水果的分形维数特征.取大小不同的温州蜜柑20个、麻阳冰糖橙17个和红富士苹果18个,设置3种水果花萼面和侧面2个方向上数字图像红色或蓝色分量阈值,将水果区域内外的红色、绿色、蓝色分量分别置为0和1,得到水果二值图像.以水果区域细化后的边界像素数和区域内像素数分别作为水果的周长和面积,以周长-面积法求得3类水果2个方向的分形维数.结果表明,3种水果花萼面的分形维数均比其侧面的分形维数小,花萼面分形维数间差异不明显,但侧面分形维数差异明显,表明仿球形水果的外形特征可用花萼面分形维数和侧面分形维数反映,但主要指标是侧面分形维数. 相似文献
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水稻中对不亲和白叶枯病菌株专一识别的多肽 总被引:1,自引:0,他引:1
经蛋白质双向电泳分析,发现水稻IR26、IR1545及TN1各有一个多肽能与不亲和的白叶枯病菌株产生特异性作用而消失,但与亲和菌株相互不发生作用。成株期抗病品种南粳l5在成株期有与不亲和菌株作用的多肽存在.而在苗期则未观察到这一多肽。对全期抗病品种IR26分析表明,它无论在成株期还是苗期均出现一个与不亲和菌株专一作用的多肽。经典遗传学分析认为有三个抗白叶枯病基因的DV85,则观察到DV85有两个以上的菌株特异性多肽。由于选些多肽表现出菌株的专一性及其它表达生理时期均与该品种的田间抗病表型一致,同时多肽的数目也与经典遗传学分析结果类似,推测这些多肽可能是抗病基因的产物。 相似文献
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[目的]研究基于ACO-SVM的粮虫特征提取,探讨粮虫特征提取的可行性。[方法]通过分析储粮害虫图像识别系统中的1个关键环节——特征提取,提出把支持向量机(Support vector machine,简称SVM)算法中交叉验证训练模型的识别率作为储粮害虫特征提取评价准则的1个重要因子,将蚁群优化算法(Ant Colony Optimization,简称ACO)应用于粮虫特征的自动提取。[结果]该算法从粮虫的17维形态学特征中自动提取出面积、周长等7个特征的最优特征子空间,采用参数优化之后的SVM分类器对90个粮虫样本进行分类,识别率达到95%以上。[结论]该研究表明蚁群优化算法在粮虫特征提取中的应用是可行的。 相似文献