小麦品种‘Waikea’抗条锈病基因的遗传分析

‘Waikea’是当前美国西北部地区大面积种植的小麦品种,研究证实该品种对中国条锈菌小种CYR31、CYR32及CYR33三种菌的混合菌苗期表现为感病,成株期表现免疫的抗性水平.采用苗期室内潜育期变温处理方法(常温昼15℃,夜10℃和高温昼24℃,夜18℃)对3个小种分别进行抗病性鉴定,明确其是否含有温敏微效基因,田间成株期抗性鉴定对其成株抗病基因进行遗传分析.结果表明‘Waikea’不含温敏微效抗病基因,至少含有一显一隐2对成株期主效抗病基因,以重叠或独立方式控制抗病性.美国西北部小麦品种‘Waikea’含有成株抗病基因,成株期对中国当前流行小种CYR33表现高抗,建议在抗病育种中加以充分利用.     

梨品种‘玉露香’抗火疫病蛋白质组学分析

由解淀粉欧文氏菌Erwinia amylovora引起的火疫病是一种重要的经济病害,严重影响着全球苹果和梨的生产。E. amylovora 被列为我国重要的检疫性有害生物。然而,植物抗火疫病分子机制尚不够明确。本研究鉴定了梨品种‘玉露香’对 E. amylovora 的抗性,开展了抗性相关蛋白质组学分析。嫩枝穿刺接种分析结果表明,‘玉露香’对 E. amylovora 表现出明显早期抗性。采用高通量蛋白组学分析技术,鉴定获得‘玉露香’和感病品种‘库尔勒香梨’的差异表达蛋白192个,其中包括29个抗病和防卫相关蛋白,13个氧化还原相关蛋白以及1个铜离子转运ATP酶蛋白HMA5。抑菌动态分析结果显示,2 mmol/L Cu2+完全抑制E. amylovora 的生长。本研究为进一步揭示梨火疫病抗性分子机制提供了候选基因。     

水稻地方品种‘月亮谷’纯系对田间稻瘟病菌的选择

云南元阳哈尼梯田稻作模式是水稻可持续生产模式之一。尽管梯田地理条件适合稻瘟病的发生,但地方品种‘月亮谷’在超百年的种植历史上未有稻瘟病大发生的记载,其原因值得探索。为了解‘月亮谷’不同抗性品系对环境中稻瘟病菌的选择作用,以‘月亮谷’单粒传纯系为材料,通过孢子捕捉法和常规病组织分离法采集稻瘟菌株,进行人工培养、表型观察,接种测定了这些稻瘟菌菌株对25个抗稻瘟病单基因近等基因系的致病型。结果表明,梯田环境空气中采集的稻瘟菌孢子菌落形态呈放射状,菌落疏松,生长在培养基浅表,产孢量总体差异不明显,黑色素颜色较浅;从水稻感病组织上分离到的稻瘟菌菌落呈地毯状,菌落紧密,匍匐在培养基表面,产孢量个体差异较大(P0.05),黑色素颜色较深。测定的稻瘟菌菌株对25个近等基因系都有致病性,联合致病性在12.0%~56.0%之间。来自环境空气中的菌株的平均联合致病性(24.8%)低于分离自‘月亮谷’纯系的菌株(38.4%)。进一步分析显示,稻瘟菌株联合致病性与其菌丝生长速率、产孢量相关性不明显;但与黑色素合成存在一定关联,颜色越深,致病性越强,来源于‘月亮谷’不同品系上的菌株致病性强于环境空气中的菌株。上述结果表明,元阳哈尼梯田环境中的稻瘟菌群体与‘月亮谷’纯系上分离到的稻瘟菌群体存在较大差异。     

水稻品种‘Rathu Heenati’、‘玉香油占’对稻飞虱及其捕食性天敌田间种群动态的影响

研究了华南双季稻区水稻抗稻飞虱种质资源‘Rathu Heenati’(RHT)和广东省超级稻主栽品种‘玉香油占’上褐飞虱、白背飞虱及田间捕食性天敌的年发生动态。结果表明,水稻品种‘Rathu Heenati’和‘玉香油占’对褐飞虱和白背飞虱均表现出明显的控制作用。褐飞虱和白背飞虱1年内在华南双季稻区存在两个明显的发生高峰,晚稻稻飞虱的发生数量高于早稻,其中早稻白背飞虱的发生数量要大于褐飞虱,而晚稻情况相反,褐飞虱的发生数量显著大于白背飞虱。当害虫虫口密度较低时,‘玉香油占’对上述两种害虫的控制作用与‘RHT’水稻差异不显著,但当稻飞虱数量急剧增加,‘RHT’对稻飞虱的控制作用就显著强于‘玉香油占’。抗性水稻‘RHT’和‘玉香油占’田的捕食性天敌如蜘蛛、盲蝽和隐翅虫虫口密度均低于感虫对照品种‘Taichung Native 1’田。捕食性天敌年发生动态调查结果表明,蜘蛛在3个品种水稻上早、晚稻各有1次发生高峰;盲蝽在晚稻有1次发生高峰,在早稻发生数量很低;隐翅虫在早稻有一个发生高峰,晚稻发生虫口密度较低。通过比较3个品种上害益虫口比年发生动态,结果表明,早、晚稻3个品种的害益虫口比均呈现“双峰型”,‘RHT’和‘玉香油占’对水稻害虫稻飞虱具有十分显著的控制作用。本文还讨论了华南双季稻区抗虫品种的培育和改良以及与其他防治措施配套综合防控稻田褐飞虱、白背飞虱的可能性。     

冬小麦品种‘兰天23号’苗期抗条锈性遗传分析

2014年在甘肃省农业科学院植物保护研究所兰州温室,进行了‘兰天23号’/‘铭贤169’组合的亲本及其F1、F2、BC1代对条锈菌主要流行小种CYR32、CYR33及新菌系G22-9的遗传分析。结果表明,接种CYR33,F2代植株抗感分离比为144R∶54S,符合3R∶1S的理论比值;接种CYR32,F2代植株抗感分离比为62R∶22S,符合3R∶1S的理论比值;接种G22-9,F2代植株抗感分离比为85R∶24S,符合3R∶1S的理论比值;F1代植株对供试菌系均表现免疫,BC1代植株抗感分离比均符合1R∶1S的理论比值,表明‘兰天23号’对3个供试条锈菌系的抗病性均由1对显性抗性基因控制。通过系谱分析推知,该抗病基因来源于抗病亲本‘SXAF4-7’。     

小麦品种田间抗纹枯病性初步评价

采用相对抗病指数法对37份材料进行了田间抗纹枯性鉴定,结果表明,小麦品种（系）间抗感性差异十分明显,但未发现免疫和高抗材料,以最后一次（乳熟期）调查结果评价,曾经和正在湖北麦区推广的品种（系）中表现抗纹枯性相对较好材料较多,荆麦66、HX8541、鄂89－11、鄂恩1号、荆35、S048等品种被评价为中等耐病,占鉴定材料总数的16．2％;征集外省材料中,云2007、宁资21、南阳82505、郑831等被评价为中等耐病,占10．8％。     

水稻品种抗纹枯病田间鉴定方法改进

田间试验表明,插大穴(基本苗30株,穴左右)诱发与常规穴(6株,穴左右)插植人工接茵秆法鉴定水稻品种对纹枯病的抗病性结果基本一致,以插大穴诱发鉴定发病更为充分,从而提出了水稻纹枯病田问新的鉴定方法,且该方法省工、节支.     

杂交中稻品种抗稻瘟病田间鉴定试验

通过对15个不同杂交中稻组合(品种)2年抗稻瘟病田间鉴定试验结果表明:特优627组合(品种)抗稻瘟病居首,其次是宜优673。特优627适合在德化县稻瘟病老病区推广种植。两优航2号已丧失抗瘟性,应淘汰,其他参试品种宜在历年稻瘟病轻发病区种植。     

‘中4’抗条锈性特点及其在抗病育种中的利用价值

小麦种质资源材料‘中4’是我国重要的小麦抗条锈亲本材料。自1994年以来连续多年进行接种鉴定和自然诱发鉴定,发现‘中4’在苗期及成株期对接种及自然诱发的条锈菌均表现免疫,抗病性表现优异。2007-2011年选用1 893份甘肃省小麦条锈菌单孢菌系进行毒性分析,仅有9个菌系对其有毒性,占0.49%。苗期接种26个国内外具有不同毒性谱的条锈菌单孢菌系,基因推导分析含有未知抗病基因。在育种中具有较好的利用价值,值得进一步研究利用。     

抗草甘膦转基因大豆‘ZH10-6’对田间生物多样性的影响

转基因大豆新品种在商业化之前必须进行环境安全评价,其中,转基因大豆对田间生物多样性的影响是环境安全评价的重要组成部分。本研究以转G2-EPSPS和GAT双价基因的抗草甘膦大豆‘ZH10-6’及其受体大豆‘中黄10’为材料,于2019年在北京顺义地区进行了大田试验,调查了不同处理对节肢动物多样性、主要病害发生、根瘤菌及杂草多样性的影响。结果表明:与非转基因大豆‘中黄10’相比,转基因大豆‘ZH10-6’不同处理田间节肢动物物种丰富度、Shannon-Wiener多样性指数、Simpson优势集中性指数、Pielou均匀性指数无显著差异;大豆霜霉病与病毒病的发病率和病情指数无显著差异;根瘤数差异不显著,大豆田杂草多样性无显著差异。研究结果为抗草甘膦转基因大豆‘ZH10-6’的环境安全性评价提供了依据。     

野生酸枣疯病与栽培大枣疯病发生的关系

为了明确野生酸枣疯病与栽培大枣疯病发生和流行的关系,采用随机徒步调查、挖根和接穗嫁接法对我国野生酸枣、栽培大枣及大枣接穗嫁接野生酸枣的枣疯病进行了田间调查,并取样检测病菌及比较不同菌株的保守基因序列.结果显示,我国野生酸枣疯病发生范围广,且地区间自然发病率差异很大,在0～40%之间;病株呈明显的团簇状分布,病菌在团簇中的根蘖苗与母株间传播或通过介体昆虫传播到后代种子苗上.在枣疯病流行区,栽培大枣发病与枣园周围分布的野生酸枣发病程度有关;用感病品系的接穗或带菌接穗嫁接到野生酸枣砧木上易导致嫁接苗发病和病害流行,而采用抗病的壶瓶枣和婆枣抗病品系接穗嫁接野生酸枣则发病率明显下降.用巢式PCR进行的病菌检测结果显示,在病害流行区酸枣或大枣无症状枝叶样品的带菌检出率为10%～32%.不同地区栽培大枣和野生酸枣上植原体的16S rDNA、16S-23S rDNA间区(SR)及核糖体蛋白基因(rp)序列比较鉴定结果显示,侵染酸枣的植原体与栽培大枣疯病植原体应为相互传染的同种致病菌.     

灰枣红点软腐病病原菌的鉴定

 The damage and symptoms of jujube fruit soft rot in Xinzheng, Henan Province, were investigated from 2006 to 2008, and the pathogen was identified based on the morphological characteristics and the ITS se-quence of ribosome DNA. The results showed that the aerial mycelium of colony was white in color in the first four days, then turned gray after incubation on PDA for 5-6 d at 25℃ and became black two weeks later. The mycelia grew luxuriantly with velvet character. The pycnidium was flask-shaped with a height of 196.9μm and a width of 213.3μm on the avereage. The conidium was colorless with single cell and had the shape of spindle, its size was (15.0-20.0)μm× (4.5-6.5)μm. The conidiophore was fastigiate. The homology of ITS sequence of ribosome DNA between the tested strain NXK and Botryosphaeria dothidea (GenBank ac-cession number:AJ938005) reached 99.87%, with a difference of only two base pairs. Based on the results of both morphological characters and molecular identification, the pathogen of jujube fruit soft rot in Xinzheng was identified as B. dothidea (Moug. ex Fr.) Ces. et de Not..     

壶瓶枣褐斑病病原菌的鉴定

 近几年来,山西红枣发生了1种严重的果实病害,症状表现为果顶或果肩部位形成红褐色的病斑。本研究以壶瓶枣为材料,对病菌进行分离。通过室内和田间致病性测定以及人工接种后再分离病菌,证明编号为CN535的真菌菌株为该病的致病菌。该病菌在PDA上7d菌落直径达69.2~73.5mm,基内菌丝和气生菌丝均发达,具明显的浅灰与墨绿色的同心轮纹;分生孢子单生或短链生,具纵横隔膜和短喙,大小为(22.5~40.0)μm×(8.0~13.5)μm,为典型的Alternaria属真菌特征。其rDNAITS序列分析结果表明该菌与A. alternata、A. tenuissima、A. longipes、A. mali和A. citri的同源性均为100%。用2对链格孢菌的专用引物AAF₂/AAR3和Aalt-F/Aalt-R分别扩增出相对应的341和450bp的片段。综合形态特征和分子分析结果,确定壶瓶枣褐斑病的病原菌为A. alternata (Fries) Keissler。     

Spatial variability of leaf wetness under different soil water conditions in rainfed jujube(Ziziphus jujuba Mill.) in the loess hilly region,China

Leaf wetness provides a wide range of benefits not only to leaves,but also to ecosystems and communities.It regulates canopy eco-hydrological processes and drives spatial differences in hydrological flux.In spite of these functions,little remains known about the spatial distribution of leaf wetness under different soil water conditions.Leaf wetness measurements at the top(180 cm),middle(135 cm),and bottom(85 cm)of the canopy positions of rainfed jujube(Ziziphus jujuba Mill.)in the Chinese loess hilly region were obtained along with meteorological and soil water conditions during the growing seasons in 2019 and 2020.Under soil water non-deficit condition,the frequency of occurrence of leaf wetness was 5.45%higher at the top than at the middle and bottom of the canopy positions.The frequency of occurrence of leaf wetness at the top,middle and bottom of the canopy positions was over 80%at 17:00?18:00(LST).However,the occurrence of leaf wetness at the top was earlier than those at the middle and bottom of the canopy positions.Correspondingly,leaf drying at the top was also latter than those at the middle and bottom of the canopy positions.Leaf wetness duration at the middle was similar to that at the bottom of the canopy position,but about 1.46-3.01 h less than that at the top.Under soil water deficit condition,the frequency of occurrence of leaf wetness(4.92%-45.45%)followed the order of top>middle>bottom of the canopy position.As the onset of leaf wetness was delayed,the onset of wet leaf drying was advanced and the leaf wetness duration was shortened.Leaf wetness duration at the top was linearly related(R²>0.70)to those at the middle and bottom of the canopy positions under different soil water conditions.In conclusion,the hydrological processes at canopy surfaces of rainfed jujube depended on the position of leaves,thus adjusting canopy structure to redistribute hydrological process is a way to meet the water need of jujube.     

沾化冬枣浆烂果病空间分布型及抽样技术研究

利用Taylor幂法则和Iwao回归法对沾化冬枣浆烂果病病果的空间分布型进行了测定,结果表明冬枣浆烂果病病果在田间呈聚集分布,且符合负二项分布,k值为1.1905。其聚集原因主要是由环境因素引起。应用Iwao抽样模型建立了沾化冬枣浆烂果病病果田间理论抽样数公式:n=(2/D)²(1.1960/m+0.7929)。并利用负二项分布零频率与均数的理论曲线公式建立了估计该病病果平均密度的零频率模型:x=1.1905(P₀^-0.84-1)。     

Effect of pruning intensity on soil moisture and water use efficiency in jujube(Ziziphus jujube Mill.) plantations in the hilly Loess Plateau Region,China

Jujube(Ziziphus jujube Mill.) is a traditional economic forest crop and is widely cultivated in hilly areas of the Loess Plateau, China. However, soil desiccation was discovered in jujube plantations. Pruning is recognized as a water-saving method that can reduces soil water consumption. In this study, we monitored the jujube plots with control(CK), light(C_1), medium(C_2) and high(C_3) pruning intensities during the jujube growing period of 2012–2015 to explore the effect of pruning intensity on soil moisture and water use efficiency(WUE) of jujube plantations in the hilly Loess Plateau Region. The results showed that pruning is an effective method for soil water conservation in jujube plantations. Soil moisture increased with increasing pruning intensity during the jujube growing period of 2012–2015. C_1, C_2 and C_3 pruning intensities increased soil water storage by 6.1–18.3, 14.4–40.0 and 24.3–63.3 mm, respectively, compared to CK pruning intensity. Pruning promoted soil moisture infiltration to deeper soil layer. Soil moisture infiltrated to soil depths of 240, 280 and >300 cm under C_3 pruning intensity, 220, 260 and 260 cm under C_2 pruning intensity, 200, 240 and 220 cm under C_1 pruning intensity, and 180, 200 and 160 cm under CK pruning intensity in 2013, 2014 and 2015, respectively. Soil water deficit was alleviated by higher pruning intensity. In 2013–2015, soil water change was positive under C_2(6.4 mm) and C_3(26.8 mm) pruning intensities but negative under C_1(–20.5 mm) and CK(–40.6 mm) pruning intensities. Moreover, pruning significantly improved fresh fruit yield and WUE of jujube plants. Fresh fruit yields were highest under C_1 pruning intensity with the values of 6897.1–13,059.3 kg/hm2, which were 2758.4–4712.8, 385.7–1432.1 and 802.8–2331.5 kg/hm~2 higher than those under CK, C_2, and C_3 pruning intensities during the jujube growing period of 2012–2015, respectively. However, C_3 pruning intensity had the highest WUE values of 2.92–3.13 kg/m~3, which were 1.6–2.0, 1.1–1.2 and 1.0–1.1 times greater than those under CK, C_1 and C_2 pruning intensities, respectively. Therefore, C_3 pruning intensity is recommended to jujube plantations for its economic and ecological benefits. These results provide an alternative strategy to mitigate soil desiccation in jujube plantations in the hilly Loess Plateau Region, which is critical for sustainable cultivation of economic forest trees in this region.     

山西壶瓶枣缩果病病原菌分离和鉴定

 2005~2008年山西壶瓶枣缩果病害发生严重,造成了巨大的经济损失。本文利用真菌ITSrDNA和细菌16S rDNA基因的通用引物,分别对分离自山西晋中的罹病壶瓶枣果实表面寄生真菌和细菌基因组DNA进行PCR扩增,将扩增产物进行核苷酸序列测定,在GenBank数据库进行Megablast同源性分析,确定壶瓶枣果实的主要寄生菌是细极链格孢菌(Alternaria alternata)、白囊耙齿菌(Irpex lacteus)、青霉菌(Penicillium expansum)、芽枝孢菌(Cladosporium tenuissimum)4种真菌和枯草芽孢杆菌(Bacillus subtilis)、巨大芽孢杆菌(B.megaterium)、短小芽孢杆菌(B.pumilus)、多粘类芽孢杆菌(Paenibacillus polymyxa)4种细菌。回接试验证明链格孢菌、青霉菌、芽枝孢菌是壶瓶枣果实主要的致病真菌,而所分离的细菌没有致病性。     

Dew measurement and estimation of rain-fed jujube (Zizyphus jujube Mill) in a semi-arid loess hilly region of China

Dew is an important water source for plants in arid and semi-arid regions. However, information on dew is scarce in such regions. In this study, we explored dew formation, amount, and duration of rain-fed jujube(Zizyphus jujube Mill) trees in a semi-arid loess hilly region of China(i.e., Mizhi County). The data included dew intensity and duration, relative humidity, temperature, and wind speed measured from 26 July to 23 October, 2012 and from 24 June to 17 October, 2013 using a micro-climate system(including dielectric leaf wetness sensors, VP-3 Relative Humidity/Temperature Sensor, High Resolution Rain Gauge, and Davis Cup Anemometer). The results show that atmospheric conditions of relative humidity of 78% and dew point temperature of 1°C–3°C are significantly favorable to dew formation. Compared with the rainfall, dew was characterized by high frequency, strong stability, and long duration. Furthermore, heavy dew accounted for a large proportion of the total amount. The empirical models(i.e., relative humidity model(RH model) and dew point depression model(DPD model)) for daily dew duration estimation performed well at 15-min intervals, with low errors ranging between 1.29 and 1.60 h, respectively. But it should be noted that the models should be calibrated firstly by determining the optimal thresholds of relatively humidity for RH model and dew point depression for DPD model. For rain-fed jujube trees in the semi-arid loess hilly regions of China, the optimal threshold of relative humidity was 78%, and the optimal upper and lower thresholds of dew point depression were 1°C and 5°C, respectively. The study further demonstrates that dew is an important water resource that cannot be ignored for rain-fed jujube trees and may affect water balance at regional scales.     

向日葵抗列当品种的田间鉴定与筛选

寄生性植物向日葵列当Orobanche cumana Wallr.已经成为我国向日葵产业发展的重要限制因素。种植抗性品种是目前控制向日葵列当最经济有效的途径。本研究在2012年－2017年以田间自然鉴定的方式对124个品种(食葵85个, 油葵39个)进行了188批次的抗列当田间鉴定试验, 参试品种包括了近10年来向日葵产区内的绝大部分市场销售品种以及部分新杂交组合。本项研究明确了上述品种的抗列当等级。筛选出免疫或高抗列当的向日葵食葵品种26个, 油葵品种25个, 其中部分商品性较好的免疫品种在向日葵列当综合防治技术集成中发挥了重要作用。结合田间试验鉴定的结果, 本文还对田间自然鉴定法存在的问题以及抗性等级的划分标准进行了讨论。