小贯小绿叶蝉在5个茶树品种（系）上的蜜露排泄量与茶树叶片结构比较

为明确茶树叶片组织结构与小贯小绿叶蝉抗性之间的相关性,在确定小贯小绿叶蝉不同龄期和虫态蜜露排泄量的基础上,比较研究了小贯小绿叶蝉雌成虫在不同茶树品种（系）上取食24 h后蜜露排泄量的差异,进而通过比较不同茶树品种（系）叶片的组织结构和色泽,分析了5个茶树品种（系）叶片的组织结构与茶树对小贯小绿叶蝉抗性能力强弱的关系。研究结果表明,小贯小绿叶蝉4龄若虫的蜜露排泄量显著高于1~3龄;雌、雄成虫的蜜露排泄量之间不具显著差异;取食中选10号的雌成虫蜜露排泄量显著低于取食其他品种;不同品种（系）茶树的叶面积、叶片总厚度、上表皮厚度、下表皮厚度以及色差等指标与雌成虫的蜜露排泄量之间无显著相关性,而叶片茸毛密度与雌成虫蜜露排泄量呈显著负相关,叶片茸毛长度与蜜露排泄量呈显著正相关。     

人参/西洋参枯叶病缓解实验

通过各供试药剂在西洋参枯叶病上的使用,验证各供试药剂对西洋参枯叶病的缓解作用。结果表明,参多乐450倍液+益微450倍液对西洋参枯叶病缓解效果突出,在一定程度上解决了枯叶病给西洋参带来的危害。且该配方在人参上同样适用。     

光伏板对吐鲁番‘无核白’葡萄叶幕微气候、叶片质量及果实品质的影响

以吐鲁番7年生‘无核白’为试验材料,研究不同密度光伏板对‘无核白’叶幕微气候、叶片质量以及果实品质的影响,旨在找到合适的光伏板密度,为葡光互补新型栽培模式的推广提供科学依据。结果表明:随着光伏板密度的增大,叶幕空气温度降低,空气相对湿度增大,光照强度显著降低。‘无核白’葡萄叶片质量、果实品质随着光伏板密度的增大呈现出先上升后下降的变化趋势,中度遮阴条件下,‘无核白’叶片的纵、横径,叶绿素含量和果实中可溶性固形物含量均表现最佳。在吐鲁番地区采用光伏板遮阴对‘无核白’葡萄叶幕微气候有显著影响,适度遮阴有利于缓解夏季高温强光对葡萄生长发育的危害,但过度遮阴会产生负面影响。在吐鲁番地区推广葡光互补栽培模式时,建议选择光伏板的间隔为1.0 m。     

不同光源对4种蔬菜幼苗叶绿素荧光及生理指标的影响

为了解不同光源或光源组合对茄子、辣椒、番茄、黄瓜幼苗叶绿素荧光及生理指标的影响,在4种基本光源的基础上,比较了不同光源处理下不同蔬菜植株叶片的叶绿素荧光参数、可溶性蛋白和可溶性糖含量。结果表明:红蓝光源不利于4种蔬菜幼苗叶片光合色素的形成,茄子、辣椒、番茄和黄瓜叶片中的光合色素含量分别在2白4红2黄、3白3红2黄、8黄或8红、8白光源下最高;茄子和番茄幼苗叶片在红蓝光源下,辣椒和黄瓜在3白3红2黄光源下,最大光化学效率和实际光化学效率都最大;茄子和辣椒幼苗在红蓝光源下所受非生物胁迫最小,叶片中可溶性蛋白含量最低,而番茄和黄瓜分别在3白3红2黄和8白光源下的可溶性蛋白含量最低;红蓝光源可明显增加4种蔬菜幼苗叶片的可溶性糖含量,对幼苗的形态建成有积极的影响。在冬春季蔬菜育苗生产中,可根据不同光源优势为不同种类蔬菜组配光源,以促进幼苗生长发育。     

中国板栗238份品种（系）叶片形态、解剖结构及其抗旱性评价

采用多功能图像分析法、冷冻切片法和指甲油印记法,对238份板栗品种（系）叶片的形态、解剖结构及气孔特征进行了观察测量,运用变异系数、主成分分析对33项指标进行了筛选,后运用隶属函数法进行抗旱性综合评价。结果表明：（1）238份板栗品种（系）33项指标中除上表皮角质层厚度、上表皮细胞宽度、第一层栅栏组织细胞密度、第一层栅栏组织细胞宽、下表皮细胞宽度和下表皮角质层厚等6项指标的变异系数小于10%,各品种系（间）差异较小外,其余27项指标的变异系数均大于10%,在各品种（系）间差异较大;经主成分分析从27项指标中筛选出10项作为238份板栗品种（系）抗旱性综合评价的典型指标。（2）利用隶属函数分析将238份品种（系）划分为4类：第Ⅰ类包括31个品种（系）,平均隶属值为0.60 ~ 0.80,抗旱性极强;第Ⅱ类包括48个品种（系）,平均隶属值为0.50 ~ 0.59,抗旱性强;第Ⅲ类包括84个品种（系）,平均隶属值为0.30 ~ 0.49,抗旱性中;第Ⅳ类包括75个品种（系）,平均隶属值为0.20 ~ 0.29,抗旱性弱。     

白桦新品种‘朝霞2号’

‘朝霞2号’是以白桦为受体获得的转BpGLK1基因干扰表达株系,其叶片中BpGLK1的表达量降低,叶绿素含量减少。主干树皮灰白色,枝条红褐色。叶片纸质,宽卵形,夏季呈黄绿色,秋季呈金黄色,叶尖呈渐尖,叶基心形,叶缘钝齿、无叶裂,上下表面均有绒毛分布,一级侧脉7 ~ 8个。     

Regional and temporal differentiation of virulence phenotypes of Puccinia triticina from common wheat in Russia during the period 2001–2018

Leaf rust, caused by the fungus Puccinia triticina, is one of the most damaging rust diseases of wheat in Russia. Populations of P. triticina were monitored in seven regions of Russia from 2001 to 2018, with a total of 5,191 single urediniospore isolates from bread wheat (Triticum aestivum) being analysed. Populations have changed significantly in all regions since 2012, after 2 years of drought (2010–2011). Regional collections of P. triticina were also significantly different between the two periods 2001–2009 and 2012–2018, with changes along two geographic gradients from West Siberia to the north-west and south-west (North Caucasia) of the European part of Russia. All tested isolates were avirulent to resistance gene Lr9 in 2001–2009 but, since 2010, virulence to Lr9 has occurred and annually increased in the Asian part of Russia (Ural and West Siberia) due to deployment of cultivars with the Lr9 gene. Virulence to Lr2a and Lr15 was considerably lower in Dagestan (6%–33%) and all European regions (35%–67%) than in Asian regions (84%–96%). During 2001–2009, virulence on Lr1 was also lower in Dagestan (33%) and the European regions (50%–77%) than in Asia (91%–96%); however, by 2012–2018, nearly all isolates were virulent on Lr1. Remarkable changes were observed in frequencies of P. triticina races defined by their virulence/avirulence to Lr1 and Lr2a genes. We postulate the P. triticina population in Dagestan is specific to that area and pathogen populations in European and Asian parts of Russia are distinct.     

Foliar lifespan,phenology and seasonal dynamics of the invasive shrub Schinus terebinthifolia

Schinus terebinthifolia is a dioecious tree native to South America that has become an invasive weed in Florida, southern California, southern Arizona, Texas and Hawaii and has been naturalised in over 20 countries. Biological control is considered a viable long-term control option for S. terebinthifolia because release from natural enemies appears to be at least partly responsible for its success in Florida. We examined leaf phenology of S. terebinthifolia over a period of 15 months at five sites in central and southern Florida to provide information that may help in predicting the impacts of potential biocontrol agents for this weed. We documented leaf lifespan, the seasonality of leaf development and abscission and the survivorship of leaves that emerged during either spring, summer or autumn. Average leaf lifespan was >4.5 months at all sites, and leaf phenology followed the seasons closely. Although S. terebinthifolia possesses leaves throughout the year, leaf production was greatest from April to September, and most leaves were abscised in February and March. Spring- and summer-emerging leaves were also longer-lived than leaves produced during autumn. These results suggest that leaves of S. terebinthifolia would be most vulnerable to herbivory during the spring and summer months when newly growing leaf tissue is most plentiful. Biocontrol agents capable of damaging these tissues during spring/summer might be an effective means of controlling this invasive weed.     

芝麻棒孢叶斑病病原菌鉴定与致病力比较

 为明确芝麻叶斑病病原菌及其致病力,本研究以河南不同地区芝麻上分离所得叶斑病分离物为研究对象,通过形态观察和分子鉴定探讨这些分离物的分类属性,并且进行离体叶片和活体茎杆接菌,进一步探究了不同菌株的致病力差异。结果显示分离所得的6株芝麻叶斑病分离物的菌落形态、生长速率和产孢量存在差异,分生孢子多数呈倒棍棒状,具隔膜,6个菌株的ITS序列与GenBank中Corynespora cassiicola的一致性达99%以上,结合形态特征与ITS序列将其鉴定为山扁豆生棒孢。室内人工接菌芝麻发现,这6个菌株的致病力存在显著的差异;在芝麻叶片上,20180909-03属强致病力菌株,20180821-01、20180909-05和20180824-01属中等致病力菌株,20180904-02-02和SF1-1属弱致病力菌株;在芝麻茎杆上,20180824-01致病力最强,其次是20180821-01、20180909-03和20180909-05,SF1-1和20180904-02-02致病力最弱。研究结果证明山扁豆生棒孢不同菌株在芝麻上的致病力存在明显的分化。     

番茄棒孢叶斑病病原鉴定及生物学特性研究

本研究采用PSA培养基对上海地区的番茄棒孢叶斑病的病原菌进行分离、培养及致病性测定,通过形态学和分子生物学方法鉴定病原菌,并对该病菌的生物学特性进行研究。结果表明:番茄棒孢叶斑病病原菌菌落呈灰褐色,菌丝质地致密、绒毛状;分生孢子单生或串生,圆柱形或倒棍棒形、顶端钝圆,基部平截,呈半透明至浅褐色,假隔膜4～10个,直或稍弯曲,基脐加厚,深褐色。结合病原菌rDNA ITS序列测定、比对后,确定该病原为多主棒孢Corynespora cassiicola。该病菌的菌丝生长最适温度为25～30℃,最适pH范围为4～8,产孢的最适温度约为25℃,最适pH范围为5～9,麦芽糖和乳糖为碳源的培养基适宜菌丝生长,可溶性淀粉和乳糖溶液中孢子萌发率最高,光暗交替条件适宜菌丝生长,孢子在水滴中极易萌发。这是该病在上海地区的首次报道。