一种应用镰刀菌酸快速鉴评瓜类枯萎病抗性的方法

【目的】针对瓜类枯萎病抗性鉴评现行方法普遍存在的费时费力等问题,建立了一种可替代尖孢镰孢菌进行黄瓜、苦瓜等瓜类枯萎病抗性鉴评的高效便捷方法,为瓜类乃至其他作物枯萎病抗性育种及抗性基础研究提供便利条件。【方法】以黄瓜、苦瓜分别为子叶平展作物和子叶不平展作物代表,选取对枯萎病菌和镰刀菌酸抗、感性状一致的黄瓜、苦瓜材料,用合适浓度的镰刀菌酸溶液处理子叶叶盘或第一片真叶,根据子叶叶盘和第一片真叶的褪绿表型鉴评瓜类枯萎病的抗感表型。【结果】在适当浓度的镰刀菌酸处理下,24 h 内抗、感枯萎病的黄瓜子叶叶盘和苦瓜真叶均出现不同程度的黄化和褪绿表型,感病材料黄化和褪绿的程度明显比抗病材料严重,与其枯萎病感 / 抗性状一致,根据颜色差异能够准确区分抗 / 感枯萎病的黄瓜、苦瓜材料及其 F2 分离群体中抗 / 感枯萎病的后代单株。【结论】镰刀菌酸处理可以用于黄瓜、苦瓜乃至其他作物枯萎病抗性的快速高效鉴评,尤其适用于对镰刀菌酸和尖孢镰孢菌抗感性状一致的作物材料。     

广东黄瓜育种研究进展

黄瓜属于葫芦科黄瓜属,喜温,不耐热,在世界各地广泛栽种。黄瓜是广东省出口北运的重要蔬菜,年种植面积达 4 万 hm2 以上。概述了广东黄瓜品种选育和相关应用基础研究的历程和进展,包括品种资源收集与创新利用、新品种选育和相关技术研究等,详细阐述了广东高校和科研院所在黄瓜雌性系育种和杂种优势利用、黄瓜抗病育种及相关基础、黄瓜耐热育种及抗逆相关基础、黄瓜其他育种相关基础技术等方面的研究进展,并指出了目前广东黄瓜在品种选育方面存在的一些问题,建议广东黄瓜育种单位加强资源收集鉴评,重视特色资源的挖掘利用和选育多样化品种,满足多元化市场需求。     

复杂背景下黄瓜病害叶片的分割方法研究

利用图像处理和模式识别技术进行复杂背景下黄瓜叶部病害的自动识别,需要先把目标叶片从复杂背景中分割出来,才能进行后续的特征提取和病害识别。为实现复杂背景下黄瓜叶片的分割,首先利用K-均值聚类算法去除图片中的非绿色部分,再采用基于laplacian of gaussia(LOG)算子的方法对待分割的叶片进行区域检测,然后进行基于形状上下文(shape context)的模板匹配和分割。为了提高匹配速度,先检测叶片的生长点和叶尖,以确定叶片的位置、尺寸和方向;然后使用基于超像素(superpixel)的最优匹配搜索方法来减少搜索的复杂度。对20幅黄瓜叶部病害图像进行分割测试,并与人工分割法进行对比,结果表明,本文所采用的分割算法能较好地从复杂背景下提取出黄瓜叶部病害图像,分割准确率达94.7%,为后期黄瓜病斑的特征提取等工作奠定了良好的基础。     

Effects of temperature, salinity and pH on larval growth, survival and development of the sea cucumber Holothuria spinifera Theel

For large-scale seed production of sea cucumbers through a hatchery system, it is imperative to know the effects of environmental parameters on larval rearing. Auricularia larvae (48 h post-fertilization) were obtained from induced spawning of Holothuria spinifera and used in experiments to ascertain the effects of temperature, salinity and pH on the growth and survivorship of the larvae. The larvae were reared for 12 days at temperatures of 20, 25, 28 and 32 °C; salinities of 15, 20, 25, 30, 35 and 40 ppt; and pH of 6.5, 7.0, 7.5, 7.8, 8.0, 8.5 and 9.0. The highest survivorship and growth rate and fastest development of auricularia indicated that water temperature of 28–32 °C, salinity of 35 ppt and pH of 7.8 were the most suitable conditions for rearing larvae of H. spinifera.     

影响刺参幼参成活和生长的几个因素的研究

在刺参人工育苗过程中，从稚参到幼参阶段极易受外界综合因子影响，成活率很低。本文采用数理统计的方法，选择四种因子对此阶段死亡率进行试验。从方差和直观分析看到稚参的附着密度和饵料品种对其成活率和生长的影响大于水温和换水方式。稚参附着密度以0．2头／cm^2为最佳，0．5头／cm^2次之；饵料以鼠尾藻磨碎液为最佳，其次是鼠尾藻液和叉鞭金藻的混合液．     

Purification and characterization of a cysteine-like protease from the body wall of the sea cucumber <Emphasis Type="Italic">Stichopus japonicus</Emphasis>

The sea cucumber (Stichopus japonicus) is able to undergo autolysis in response to a variety of environmental and mechanical cues. Within the framework of a long-term study of this phenomenon we have purified a protease from the body wall of the sea cucumber by means of ion-exchange chromatography with DE-52 cellulose and gel filtration chromatography with Sephadex G-100. The final enzyme preparation was nearly homogeneous on polyacrylamide gel electrophoresis, and its molecular weight was estimated to be approximately 35.5 kDa. The purified enzyme exhibited a maximum activity for the hydrolysis of casein at pH 7.0 and 50°C and a remarkable stability at pH 4.0–7.0 and 40–60°C. Based on the inhibition and activation profiles obtained with numerous specific protease inhibitors and an activator, the protease purified from the body wall of the sea cucumber was defined to be a cysteine-like protease.     

不同叶面肥对黄瓜产量和品质的影响

为了探索黑龙江省东部地区黄瓜叶面肥的施用效果,以黄瓜品种中农6号为试材,设4个叶面肥处理,分别施用利果美、金牌、凯丰和巨尔,研究了同种浓度不同功效的叶面肥对大田黄瓜产量和品质的影响。结果表明:4种叶面肥均有提高黄瓜产量、VC含量和可溶性蛋白含量的作用,其中1 000倍液巨尔叶面肥处理的黄瓜产量和品质与对照差异极显著。     

Comparison of Physiological Properties Between Dwarf and Vinetype Cucumbers （Cucumis sativus Linn.）

Dwarfism is one of the most important traits in crop breeding. In this study, a dwarf cucumber D0462 and a vine NA129 were taken as experimental materials. The metabolism of hydrogen peroxide （H2O2） and superoxide anion radical （O2-·, activities of antioxidant enzymes, and the levels of endogenous hormones of the two cultivars were compared. In the whole growth period, D0462 maintained higher H2O2 and O2-· levels than NA129. The activities of SOD （superoxide dismutase）, CAT （catalase）, APX （ascorbate peroxidase） and IAAO （indoleacetic acid oxidase） in D0462 were found higher than those in NA129. The contents of gibberellic acid （GA3）, indole-3-acetic acid （IAA）, zeatin riboside （ZR） and jasmonic acid （JA） in intemode were determined by enzyme-linked immunosorbent assay （ELISA）. The intemode ofD0462 remained lower levels of GA3, IAA, and ZR. In contrast, JA level in internode of D0462 was higher than that of NA129. Compared with NA129, the cell mumbers in intemode of D0462 did not change, but cell size evidently decreased. The chloroplasts in mature mesophyll D0462 exhibited swollen filled with starch grains instead of regular oval ones, and thylakoids of chloroplast swelled and became ambiguous.     

碳晶电热板在日光温室黄瓜冬季育苗中的应用效果

为明确碳晶电热板在日光温室冬季黄瓜育苗中的应用效果,以日光温室正常培养(不加温)和发热电缆(敷设功率为100W/m2)加温为对照,研究碳晶电热板加温对基质温度、耗电量、黄瓜幼苗生长和生理特性影响;以日光温室正常培养(不加温)为对照,研究隔热层在碳晶电热温床育苗中的节能效果差异。结果表明:1)80W/m2敷设功率的碳晶电热板加温的夜间基质温度能达到并保持目的温度(18℃),比对照最低温度和平均温度分别高12.1和6.07℃,比发热电缆处理最低温度和平均温度分别高7.0和3.05℃,耗电率比发热电缆处理的减少34.4%;2)黄瓜出苗时间为1.3d,比对照处理减少4.0d,比发热电缆处理减少2.0d;3)80W/m2碳晶电热板加温处理的黄瓜壮苗指数比对照处理增加144.4%,比发热电缆处理增加46.7%;4)与不使用隔热层的碳晶电热温床相比,使用聚苯乙烯板和无纺布制作成的隔热层的电热温床的日平均温度分别提高2.3和1.9℃,耗电率减少22.6%和21.2%,黄瓜壮苗指数提高50.0%和43.8%。说明碳晶电热板加温是适合我国华北地区冬季设施黄瓜育苗的加温方式,敷设功率以80W/m2为宜;聚苯乙烯板和无纺布是适合碳晶电热温床使用的隔热材料。