不同肥料组合对东方百合种球繁育的影响

本实验采用4种肥料组合并以不施肥为对照,对东方百合进行追施。研究不同肥料组合对东方百合种球生长的影响,结果表明,追施N、K肥料组合最有利于种球周径的膨大,重量的增加。     

烘烤温湿度变化对不同烤烟品种烟叶膜脂过氧化作用的影响

以云烟85、K326、红花大金元(HD)3个烤烟品种为供试材料,研究了不同烤烟品种烘烤过程中温湿度变化及烟叶脱水速率对烟叶膜脂过氧化作用的影响.结果表明:烟叶含水率的变化与烤房相对湿度的下降幅度密切相关;红花大金元烟叶对烤房温湿度的变化比云烟85、K326烟叶更为敏感,脱水速率更快;烟叶脱水速率过快是导致剧烈膜脂过氧化作用和丙二醛含量大幅升高的直接原因.烘烤过程中过氧化物酶的活性除受烤房温度的影响外,还与细胞膜过氧化导致丙二醛浓度升高有关.丙二醛可以作为烘烤过程中烟叶脱水速率和细胞膜结构破坏程度的指示性化合物.     

东方白鹳与家禽消化器官形态特点的比较

用东方白鹳，鸡，鸭和鹅各４只，采取主要消化器官，进行常规组织学观察与测量，与家禽比较，东方白鹳食管长，无素囊，食管粘膜上皮薄，食管腺不发达，腺胃体积大，肌胃较小，小肠较短，但十二指肠发达；大肠较短，其中盲肠退化，肠壁内充满了淋巴组织；胆囊呈梭形，肝管和胆囊管分Ａ，Ｂ，Ｃ三型，胰岛数量较多。     

Sex-related differences in the tolerance of Oriental fruit moth (Grapholita molesta) to organophosphate insecticides

In vivo toxicity assays have shown that organophosphate insecticides are less toxic to male than to female Oriental fruit moths Grapholita molesta. While male moths have higher levels of acetylcholinesterase and general esterase activities, female moth acetylcholinesterase enzymes are less sensitive to aromatic and aliphatic organophosphates than male enzymes. Elevated esterase and acetylcholinesterase activities in male moths explain their greater tolerance to aromatic and aliphatic organophosphates. Male and female acetylcholinesterase enzymes are equally tolerant to heteroaromatic organophosphates, the most widely used of this class of insecticides in G molesta control. This observation, in contrast to the greater sensitivity of male acetylcholinesterases to aromatic and aliphatic organophosphates, shows the potential for the evolution of insensitive target sites in male moths, which would increase male G molesta tolerance to these insecticides. Significant sex-linked differences in insecticide tolerance have not been reported previously in lepidopterans. The practical implications of the observed differences in tolerance in male and female G molesta question the practice of using pheromone traps to monitor populations of these moths in orchards.     

Effects of plant essential oils and components from Oriental sweetgum (Liquidambar orientalis) on growth and morphogenesis of three phytopathogenic fungi

Commercial plant essential oils obtained from 40 plant species were tested for their antifungal activity against Phytophthora cactorum, Cryphonectria parasitica, and Fusarium circinatum. Strong antifungal activity against Phytophthora cactorum was achieved with the essential oil derived from Oriental sweetgum, Liquidambar orientalis at 28 × 10⁻³ mg/mL air concentration. In a test with C. parasitica, inhibition rate of patchouli was 51.0%, whereas the other essential oils showed weak activity. Essential oils of manuka (Leptospermum scoparium) and patchouli (Pagostemon patchouli) showed moderate activity against F. circinatum. Analysis by gas chromatography-mass spectrometry led to identification of 11 compounds in the oil of L. orientalis. The antifungal activity of identified compounds was tested singularly by using standard or synthesized compounds. Inhibition rates of cinnamyl aldehyde and benzaldehyde were 100% against P. cactorum at 28 × 10⁻³ mg/mL air concentration. There was a significant morphological alternation in three phytopathogenic fungi after oil or compound treatment.     

桔小实蝇寄主选择性的研究与应用

综述了桔小实蝇成虫对寄主果实选择及应用的研究概况。桔小实蝇成虫对寄主果实的选择表现为对果实不同部位的选择、同种寄主不同成熟度果实的选择、同一寄主不同品种的选择、不同寄主果实的选择四个方面。桔小实蝇成虫对寄主果实的选择主要受果实挥发性物质(包括自然释放和虫害诱导释放)、果实的品质性状、颜色、取食经历及记忆行为和昆虫内共生菌等因素的影响。     

镉在薄皮甜瓜植株中的分布及低积累品种筛选

通过大田镉污染土壤栽培,对薄皮甜瓜不同部位的镉含量和果实品质进行分析。结果表明:参试的12个不同类型薄皮甜瓜果实镉含量均低于《食品安全国家标准食品中污染物限量》GB 2762—2012规定的甜瓜果实中镉的限量指标(0.05mg·kg~(-1)),其中IVF-28果实内镉含量最低,仅为0.015 3 mg·kg~(-1)。镉在甜瓜植株体内的分布规律为基部茎叶根上部茎叶果实,综合果实镉含量和品质性状,筛选出IVF-28为适于重金属镉中度及以下污染区种植的薄皮甜瓜品种。     

东亚飞蝗不同食料笼养试验研究

在东亚飞蝗示范试验区内笼养试验结果表明,东亚飞蝗喜食芦苇、稗草等禾本科和莎草科植物,不喜食苜蓿和香花槐等豆科植物,在东亚飞蝗灾区推广种植这两种植物可控制东亚飞蝗的发生。     

黄土半干旱区土壤水分对侧柏叶片水气交换影响

2002年4～10月,在山西省方山县径流林业试验基地,通过水分控制措施形成土壤水分梯度,对野外栽植的侧柏叶片进行了蒸腾、光合及环境因素的观测。结果表明:侧柏叶片的蒸腾速率与土壤含水量有密切的关系,随着土壤含水量的降低水分胁迫加剧,蒸腾速率显著降低,而且一般受到水分胁迫的树体在低光照条件下出现蒸腾的峰值,随着光照与气温的增加蒸腾速率下降,水分胁迫程度越严重蒸腾峰值出现的时间越早。当土壤含水量没有造成水分胁迫时,侧柏叶片的蒸腾速率日变化与光照及气温的变化相一致。试验条件下,春季土壤含水量在5.79%以下时产生了严重的水分胁迫,土壤含水量达到6.50%时相对水分胁迫较轻;夏季土壤水分在6.94%以下时产生严重水分胁迫;秋季没有产生水分胁迫,但是仍然是土壤含水量较高时蒸腾速率也较高,这为黄土高原地区布设相应的径流林业措施,进行有效的土壤水分管理提供了依据。     

黄土高原半干旱区林木生长适宜土壤水分环境的研究

采用 L I- 62 0 0型植物光合测定系统、L I- 160 0型稳态气孔计和 L NW- 5 0 A型中子水分测定仪 ,对不同土壤水分胁迫下刺槐、侧柏林木和苹果树及其盆栽苗木生长的生理、生态特征进行实地观测 ,研究了叶片净光合速率( Pn)、蒸腾速率 ( Tr)、羧化效率 ( CE)、叶片水分利用效率 ( WUEL)以及气孔导度 ( Cs)和气孔阻力 ( Rs)对土壤含水量 ( SWC)变化的响应过程。结果表明 :刺槐、侧柏和苹果净光合速率最高时的 SWC分别为 17.13 % ,15 .90 %和 16.11% ;维持其最高净光合速率 70 %以上的土壤含水量 (即气孔导度的土壤水分响应曲线转折点对应的土壤含水量 )临界值分别为 10 .5 0 % ,9.5 0 %和 9.75 % ;其蒸腾速率最高时的 SWC分别为 18.82 % ,19.70 %和16.3 3 % ;其叶片水分利用效率最高时的 SWC依次为 13 .2 3 % ,10 .66%和 12 .3 8% ;其羧化效率最高时的 SWC依次为 15 .70 % ,15 .5 0 %和 15 .83 %。根据半干旱地区林业建设以提高林木水分利用效率为核心的土壤水分管理思想 ,分别选取维持最高叶片水分利用效率的土壤含水量临界值和维持较高光合速率 (最大光合速率的 70 %以上 )的土壤含水量临界值作为林木生长适宜土壤水分环境的上、下限标准。这一标准概化为 :刺槐 10 .5 %～ 13 .5 % ,侧柏 9.5 %～ 10 .5 %