中国芒果输出蒸热杀虫处理研究

中国芒果输出蒸热杀虫处理研究,包括海南产金煌、爱文、象牙和台农1号4个品种芒果鲜果内橘小实蝇Bactrocera dorsalis(Hendel)的卵和不同龄期幼虫的耐热力试验;芒果小规模、大规模蒸热杀虫处理试验;以及蒸热处理对芒果品质的影响等。结果显示,当蒸热室温度逐步达到50℃,芒果果心温度上升至47℃(使用饱和热蒸汽)并保持这一温度时,在不同处理时间(0、5、10、15、20min)条件下,不同品种芒果内橘小实蝇的耐热力由强至弱的发育期依次为2龄幼虫→3龄幼虫→1龄幼虫→卵,其中以金煌芒果(海南产芒果品种中果体最大,平均重量856g)内2龄幼虫的耐热力最强。完全杀灭海南产金煌芒果内橘小实蝇的卵和幼虫的蒸热条件是果心温度保持在47℃和使用饱和热蒸汽处理20min。金煌芒果的小规模、大规模蒸热杀虫处理试验的结果进一步确认和验证,在上述的蒸热处理条件下,总计数量分别为14000头和35000头最具耐热力的供试橘小实蝇2龄幼虫全部被杀灭(死亡率100%),完全可确保其检疫安全。同时,经蒸热杀虫处理后第7d和第12d的金煌芒果鲜果与对照鲜果品质(包括色泽,以及还原糖、蔗糖、总糖、总酸、维生素C和可溶性固形物的含量)的比较测定数据表明,蒸热温度47℃和使用饱和热蒸汽处理20min,除维生素C的含量有微量损失外,基本可保持鲜果的品质不变。     

芒果不同部位挥发物及横线尾夜蛾对其触角电位反应

【背景】芒果横线尾夜蛾是严重危害芒果花序和嫩梢的重要害虫,其发生面积不断扩大,给我国南方芒果造成了巨大损失。【方法】通过气质联用仪（GC-MS）对芒果花、梢和成熟果实的挥发性物质及其相对含量进行分析;采用触角电生理方法,测定不同性别和交配状态的芒果横线尾夜蛾对12种芒果挥发物的触角电位反应。【结果】芒果3个部位的挥发性物质多为萜烯类化合物,主要物质（相对含量在O．06％以上）的数量分别为芒果花中22种、梢11种和成熟芒果13种。芒果花中含量较高的为d．水芹烯（43．64％）和异松油烯（29．33％）;芒果梢中α-古芸烯（23．63％）含量最高;成熟芒果中8-石竹烯含量最高,为29．47％。仅异松油烯和β-荜澄茄油烯在芒果3个部位中均被检测到,但其含量差异较大;异松油烯在花、梢、果实中的含量分别为29．33％、19．99％、0．59％,而β-荜澄茄油烯分别为3．51％、2．18％、6．05％。芒果横线尾夜蛾未交配雌、雄蛾和已交配雌、雄蛾对同一种化合物的触角电位相对值之间均无显著差异。4种成蛾对反-2-已烯醛的触角电位反应值与其他化合物相比均有显著差异。交配后雌、雄蛾的触角电位反应值均有所降低,但与交配前相比无显著差异。【结论与意义】筛选出的反-2-己烯醛可作为横线尾夜蛾信息素的增效物质,对性引诱剂的研制具有重要意义。本研究可为从化学信号角度阐明横线尾夜蛾寄主定向和雌、雄交配机理,以及其致害机理提供依据。     

云南河口县桔小实蝇生物学特性及防治

桔小实蝇Bactroceradorsalis (Hendel)在河口 1年发生 5代 ,世代重叠 ,5～ 8月为害虫发生盛期 ,以第 2和第 3代幼虫发生期对当地果蔬作物的危害最重。室内 1 8～ 30℃条件下 ,成虫日羽化高峰发生在上午 9:0 0～ 1 0 :0 0 ,卵、幼虫和蛹的历期随着温度的升高而缩短。成虫取食喜选成熟芒果的汁液。提出了防治此害虫的主要措施。     

高粱条螟在湘北地区的发生动态

用越冬幼虫及其后代研究了高粱条螟Procerasvenosatus (Walker)的年生活史和未成熟的发育分级特征。结果表明 :卵、幼虫、蛹分级分龄选用的特征比较明显、稳定 ;高粱条螟在湘北地区为兼性滞育昆虫 ,幼虫既能以滞育方式越冬、越夏 ,也能以滞育方式越冬连越夏或者越夏连越冬 ,每年发生 1～ 2代 ;各虫态历期为 :成虫产卵前期 2～ 3d ,卵期 7～ 1 0d ;1龄幼虫期 2～ 3d,2龄 6～ 7d ,3龄 5～ 7d,4龄 9～ 1 1d ,5龄 8～ 1 0d ,6龄 1 1～ 1 2d ,蛹期 9～ 1 1d。     

茶黑刺粉虱蛹和卵的发育分级及与其防治适期的相关性

20 0 0年 4～ 6月 ,每 5日在皖南黑刺粉虱Aleurocanthusspiniferus(Quaintance)常发茶园中以平行跳跃法选 5 0个样方。每样方为 1m茶行 ,查其上、中、下层各 2片成叶上各虫态粉虱的数量 ;采回 2 0 0头蛹于立体显微镜下解剖。越冬代蛹期 32～ 38d。据蛹体形态和颜色的显著变化而分为 4级 :体液乳白色( 1 2～ 1 4d)、体液淡黄色 ( 6～ 8d)、体液橙红色 ( 1 1～ 1 2d)和体液淡紫色阶段 ( 3～ 4d)。引入该粉虱于盆载茶苗上 ,观察其生物学习性。第 1代卵期 2 2～ 2 8d ,据卵颜色的显著变化分为 4级 :乳白色 ( 2～ 4d)、淡黄色 ( 2～ 3d)、橙红色 ( 1 5～ 1 7d)和紫黑色阶段 ( 3～ 4d)。第 1代幼虫期 2 5～ 2 8d ,其中 1龄 9～ 1 2d ,2龄 9d ,3龄 7d ,蛹期 7～ 8d。越冬代成虫盛期和第 1代 1龄盛期为防治适期 ,可较好地用蛹或卵的分龄分级法预测。越冬代蛹全部羽化之时 ,又恰是 1龄幼虫盛期 ,易于掌握     

光照、温度对纵坑切梢小蠹起飞行为的影响

纵坑切梢小蠹有明显的趋光性。在光照为 1～ 4 0 0 lx范围内 ,趋光性随光照强度提高而增强。完全黑暗条件下 ,蠹虫起飞量极少。在光照 10 0 0 lx,温度 2 5℃下 ,蠹虫起飞率达 77.7%。研究认为 ,温度和光照是纵坑切梢小蠹起飞的重要环境因素     

Bt玉米(MG95)对粘虫的抗性和拒食作用

在室内以我国自主培育的转Bt基因玉米 (简称 :Bt玉米 )为材料 ,测定了Bt玉米对不同龄期 ( 1～ 4龄 )粘虫PseudaletiaseparataWalker的影响。测定指标包括 :幼虫体重、幼虫发育历期、幼虫死亡率、化蛹率、蛹重、蛹历期、羽化率、产卵量、成虫历期、卵孵化率。结果显示 :用Bt玉米喂养的 1～ 4龄幼虫在处理 6d及 1～ 3龄幼虫在处理 9d时的体重与对照相比均差异显著 ;除 1龄幼虫外 ,2～ 4龄幼虫处理 6d及 2～ 3龄幼虫处理 9d后的死亡率差异不显著 ;用Bt玉米喂养的各龄幼虫发育历期延长 ,与对照相比差异显著 ;1、2龄幼虫的化蛹率与对照相比有显著差异 ,3、4龄则差异不显著 ;1～ 4龄幼虫的蛹重、蛹历期及羽化率均差异显著 ;成虫历期仅 1龄幼虫差异显著 ;与对照相比 ,各龄粘虫的产卵数、卵孵化率均无显著差异。结果表明 ,1龄幼虫对Bt玉米最为敏感。另外 ,拒食实验结果显示 ,在实验开始后的 8,1 6,2 4,3 2及 48h ,非选择性测定的拒食率为 63 2 0 ,64 60 ,48 99,2 3 3 5和 0 5 4% ,选择性测定的拒食率为98 3 3 ,82 43 ,71 5 4,40 1 6和 0 2 7% ,总体趋势是拒食率随时间延长而降低 ,48h后Bt玉米对粘虫幼虫无拒食活性。     

为害荔枝的茶黄蓟马生物学特性及防治

茶黄蓟马是近年来发现的危害四川荔枝秋梢的重要害虫 ,在四川 1年发生 1 0～ 1 5代 ,以成虫在荔枝、龙眼树皮裂缝及茶花中越冬 ,1年 4季均可发现 ,危害新梢叶片、顶芽 ,使抽花枝头减少 ,树势衰弱 ,减产甚至失收。用 7 5 %虫霸乳油防治效果达 95 %,其当地优势天敌有草蛉、瓢虫、小花蝽和跳蛛等     

枸杞木虱啮小蜂寄生行为及生物学特性的研究

枸杞木虱啮小蜂Tetrastichussp .是枸杞木虱ParatriozasinicaYang&Li若虫的外寄生蜂 ,自然寄生率可达 86 5 %。在温度为 2 0～ 2 5℃的室内条件下 ,完成 1个世代需 1 4～ 2 0d。成虫寿命与取食有关 ,取食 1 5 %的蜂蜜水 ,雌性成虫寿命为 1 2～ 1 7d,雄性成虫为 4～ 6d。成蜂最喜欢在 3龄和 4龄若虫上产卵。自然种群消长与寄主虫口密度相关。每年 7月到 8月下旬该蜂寄生率高 ,9月份下降 ,1 0月份几乎不见。     

三角鲤的繁殖与生长特性

对三角鲤的年龄与生长、食性和繁殖进行了研究。三角鲤体长和体重相关 ,关系方程式为W =0 0 1 1 3 71L3 3 2 44。 3 龄以前生长较快 ,生长指标高 ,体长和体重的瞬时生长率大。其生长规律符合VonBertalanffy方程 :Lt=5 7 2 5 [1 -e-0 11717(t 2 9614 7) ];Wt=6762 0 4[1 -e-0 11717(t 2 9614 7) ]3 。生长拐点tr=6 41龄。其食性是以底栖动物为主的杂食性鱼类。性成熟年龄雌鱼为 3 龄 ,雄鱼为 2 龄 ,相对繁殖力为 5 5～ 88粒 g体重。一年多次产卵 ,产卵盛期为 4～ 5月 ,胚胎发育所需积温约为 2 3 0 0℃·h。     

应用PV技术对7种针阔叶幼树抗旱性的研究

为进一步探讨PV(Pressure-Volume)技术在树木抗旱性研究中的应用前景,比较成、幼龄树木的抗旱性差别,在对樟子松等7种成龄树木抗旱性生理指标研究的基础上,对其幼树的抗旱性进行了研究。结果表明,对成、幼龄树木一年生小枝用PV曲线所测得的诸水分状况参数随年生长发育进程的的变化规律是一致的;用嫩枝生长初期和枝条完全木质化时期两个阶段的水分参数比较树木的抗旱性、具有较大的可靠性和实用性;幼树在嫩枝生长初期的抗旱性较成树弱,当新枝完全木质化之后,二者的抗旱性基本相近。     

补光对大棚火龙果冬季促花的影响

为探讨夜间补充光照对大棚火龙果冬季植株促花的效应,以2年生‘短芯’红肉(心)火龙果植株为试材,每天夜间补光6 h,以不补光为对照,观测火龙果枝条抽蕾状况。结果显示,在平均光强500 lx、每天补充光照6 h、连续补光45 d条件下,第一批次植株抽生花蕾率达83.3%,老枝(枝龄≥12个月)抽生花蕾率为15.2%,青枝(枝龄＜12个月)抽生花蕾率为28.0%,抽生花蕾枝条占植株总枝条数的21.4%;枝条花蕾数占枝条上芽点数的比率,老枝为2.7%、青枝为2.9%。而对照植株没有抽生花蕾,抽蕾率为0。表明夜间补充光照可有效地促进大棚火龙果冬季植株抽花。     

荒漠植物黑沙蒿嫩枝与成熟枝内生菌群落结构差异

[背景]黑沙蒿是我国北方沙漠地区分布广泛、抗旱性能优良的固沙灌木,对稳定沙漠地区生态系统有至关重要的作用.[目的]内生菌在植物生命过程中扮演着重要角色,认识植物生长发育阶段幼嫩和成熟组织内生菌群的结构变化,对于理解菌群间的相互作用及保护宿主植物抵御生物和非生物胁迫具有积极意义.[方法]以宁夏拉巴湖林场黑沙蒿为研究对象,...     

Plant age, communication, and resistance to herbivores: young sagebrush plants are better emitters and receivers

Plants progress through a series of distinct stages during development, although the role of plant ontogeny in their defenses against herbivores is poorly understood. Recent work indicates that many plants activate systemic induced resistance after herbivore attack, although the relationship between resistance and ontogeny has not been a focus of this work. In addition, for sagebrush and a few other species, individuals near neighbors that experience simulated herbivory become more resistant to subsequent attack. Volatile, airborne cues are required for both systemic induced resistance among branches and for communication among individuals. We conducted experiments in stands of sagebrush of mixed ages to determine effects of plant age on volatile signaling between branches and individuals. Young and old control plants did not differ in levels of chewing damage that they experienced. Systemic induced resistance among branches was only observed for young plants. Young plants showed strong evidence of systemic resistance only if airflow was permitted among branches; plants with only vascular connections showed no systemic resistance. We also found evidence for volatile communication between individuals. For airborne communication, young plants were more effective emitters of cues as well as more responsive receivers of volatile cues.     

国产柽柳科3属6种植物营养枝的解剖观察

对国产柽柳科3属6种植物(琵琶柴、沙生柽柳、山川柽柳、多枝柽柳、刚毛柽柳、疏花水柏枝)营养枝解剖结构的比较研究表明：其当年生营养枝在表皮是否具毛、皮层细胞的形态结构、维管束排列方式、形成层的发生、髓部面积及内含物等性状上存在差异,并根据这些差异列出了分属检索表。所选6种植物生态型各不相同,其中琵琶柴为地带性超旱生小半灌木,柽柳为非地带性的潜水性旱、中生灌木,疏花水柏枝为湿、中生灌木。通过比较这6种植物的解剖结构,发现随着生境由湿生向旱生变化,营养枝解剖结构也发生了相应的变化,并与生境形成了良好的适应。     

Naringin Levels in Citrus Tissues : II. Quantitative Distribution of Naringin in Citrus paradisi MacFad

The quantitative distribution of the flavanone-7-neohesperidoside, naringin, in seeds, seedlings, young plants, branches, flowers, and fruit of Citrus paradisi Macfad., cv `Duncan' was analyzed by radioimmunoassay. High levels of naringin were associated with very young tissue and lower levels were found in older tissues. Seed coats of ungerminated seeds and young shoots had high naringin concentrations whereas cotyledons and roots had very low concentrations. Light-grown seedlings contained nearly twice as much naringin as etiolated seedlings and, in young plants and branches, the naringin content was highest in developing leaves and stem tissue. In flowers, the ovary had the highest levels of naringin, accounting for nearly 11% of the fresh weight. There was a net increase in the total naringin content of fruits during growth. However, due to the large increase in fruit size, there was a concomitant decrease in the naringin concentration as the fruit matured.     

Seasonal patterns of cell-to-cell communication in Chara corallina Klein ex Willd. II. Cell-to-cell communication during the development of antheridia

Cell-to-cell communication has been studied in lateral branches and developing antheridia of male Chara corallina plants. The moving cytoplasm is specialized to include essentially separate ascending and descending cytoplasmic streams within the inter-nodes. The neutral line which demarcates the ascending from the descending stream is established by the divisions of the nodal initial, which gives rise to both the node and internode. The ascending stream is located beneath the first-formed node-cells and the descending stream beneath the last-formed cells. The cells destined to develop into antheridia were always located on the same side as the descending internodal stream, and thus, were derived from the cells last formed during divisions of the nodal initial. Three stages of anther idial development have been defined: (1) young antheridia from the initial division of a node-cell to the formation of an octant structure; (2) maturing antheridia where differentiation into shield, manubria and capitular cells has occurred, including antheridia where an internal cavity has formed but contains filaments of less than 32 cells; and (3) mature antheridia where filaments contain more than 32 cells and spermatid production commences. Internodal cells of branches bearing young antheridia had similar characteristics to spring branches, including high plasmalemma potential differences (-217·7±31·5mV, [K⁺]_o 0·5 mol m^?3; pH 7·6) and extensive cell-to-cell communication (frequency of intercellular transport of 6 carboxyfluorescein 86%). The small probe 6 carboxy fluorescein moved into the entire young antheridium in 100% of injections. The molecular exclusion limit for internodes and the nodal complex lay between 874 and 1678Da whereas the exclusion limit for the young antheridium was smaller (between 750 and 874Da). Internodal cells of branches bearing maturing antheridia had similarly high PDs (–221·7±40mV; [K⁺]_o 0·5 mol m^?3; pH 7·6). Cell-to-cell communication between internodes bearing maturing antheridia was extensive (frequency of intercellular transport of 6 carboxyfluorescein 100%). The shield cells were isolated from the symplast of the thallus at this stage since they did not admit 6 carboxyfluorescein. Internodal cells of branches bearing only mature antheridia showed different characteristics. Intercellular communication between internodes was restricted to a level similar to that found in winter (frequency of intercellular transport of 6 carboxyfluorescein = 57%). The mature antheridium was entirely isolated from the symplast of the thallus. A period of extensive cell-to-cell communication and high PDs in internodal cells commences in vegetative lateral branches in spring, immediately before reproductive structures are initiated. These features persist throughout summer whilst reproductive structures develop, until the antheridial filaments contain 32 or more cells (mature stage), at which point spermatid production commences and the antheridium is isolated from the thallus. In autumn, following the stage of mature antheridia, no further antheridia are initiated. Internodes are subsequently vegetative throughout winter and their lateral branches are characterized by restricted cell-to-cell communication, low internodal PDs, and little obvious growth, all features consistent with winter dormancy.     

Developmental responses of individual Onobrychis plants to spatial heterogeneity

An experimental study was undertaken to assess the extent to which better-situated branches correlatively inhibit other branches on the same plant which are growing in relatively inferior conditions. The experiments were carried out on naturally-grown Onobrychis squarrosa L. (Papilionaceae), a dominant annual plant of the Mediterranean region of Israel. Treatments were carried out (i) on young plants that only had a seminal shoot, and (ii) on plants after lateral branches had started growing. Differential shade conditions were achieved by the repeated removal of neighbours on one side of the plants. The plants were either left intact or damaged by removing different parts of their branch system. In intact plants, growth responses to the differential light conditions which were expressed by the number of branches, leaves and fruits showed some evidence for support of the shaded branches by the exposed branches on the same plant. In contrast, heterogeneous treatments of both shade and branch damaging led to development that reflected marked correlative inhibition of the shaded parts of the plant. The results show that a latent potential for correlative inhibition between branches exists throughout plant development and that in Onobrychis it can be readily realised when plants are damaged. This could depend on known traits of auxin acting as a correlative signal of growing branches. The observed responses of Onobrychis can be understood as an adaptive strategy which reflects the low reliability of environmental signals and the high cost of changing the course of development, especially in short-lived annual plants.     

克隆乔木黄牛奶树枝条的功能特征

黄牛奶树(Symplocos laurina)是一种乔木克隆植物,其枝担负着支撑叶进行光合作用和克隆苗繁殖两种功能。由于枝功能的特异性在形态上表现出独特的特征:上部的枝生长比较旺盛,主要进行光合作用负责整个植株的碳水化合物供应与积累;下部的枝在形态上有所变化,基部细长而端部较基部明显增粗,并下垂呈“V”状,在生长过程中增长明显而无明显增粗现象,主要进行克隆繁殖。黄牛奶树的枝在由营养功能转变为繁殖功能的过程中年萌发次数显著增加;枝分化成克隆苗后在截取光能方面采取了不同的策略:克隆苗作为一个新的生命体,主要通过增加叶量占据更大的水平空间来增大总叶面积以截取更多阳光,不同于营养枝通过增加单叶面积占据更大的垂直空间来增大总叶面积以截取更多阳光的方式,但在不同的生境下对照枝与压枝克隆苗达到的总叶面积却无显著差异;从各构件的生物量特征看, 对照枝的生物量主要分配在叶和叶柄等光合构件上,而枝分化成克隆苗后生物量主要分配在茎上。即黄牛奶树的枝随着着地后功能的变化,在形态等各方面都有相应的变化,这可能是由于功能变化后内源激素发生变化的结果,但这有待于进一步研究。