棉花早衰、红叶茎枯病与棉花轮纹斑病间关系辨析

 系统分析了棉花早衰、红叶茎枯病与棉花轮纹斑病间的关系。棉花早衰依据其成因差异可划分为3种类型，分别为生理性早衰、病理性早衰及生理病理复合性早衰。近些年来生理病理复合性早衰在我国发生最为普遍，危害最为严重。系统分析了生理病理复合性早衰的成因及有关研究进展，在此基础上，提出适宜我国棉花生产、以“选种、壮苗、补钾、抗逆、防病”等技术为核心的棉花早衰控制技术体系。     

Identifying the Pathogen of Cotton Leaf Spot Based on the Analysis of rDNA-ITS and Histone 3 Gene Sequence in Xinjiang

[Objective] The objective of this experiment is to identify pathogens causing cotton leaf spot in Xinjiang. [Method] Two hundred and six leaf samples displaying typical leaf spot symptoms were collected from 30 loci in 7 different regions of Xinjiang in 2016 and 2017. The fungal isolates were purified using conventional methods. Ten representative fungal strains were selected for further tests based on different sampling times, locations, and colony characteristics. The strains were identified based on their morphological characteristics and the sequence analysis of both rDNA internal transcribed spacer and histone 3 gene. [Result] In north of Xinjiang, Alternaria alternata and A. tenuissima were the dominant pathogens at the seedling stage (from May to June), whereas in August and September, A. tenuissima was the main pathogen and few were A. alternata and A. macrospora. In south of Xinjiang, A. tenuissima was the main pathogen at the seedling stage, whereas in August and September, A. tenuissima and A. macrospora dominated. Further, Gossypium hirsutum and G. barbadense was mainly infected with A. tenuissima and A. macrospora, respectively. [Conclusion] The main pathogens causing cotton leaf spot in Xinjiang are A. alternata, A. tenuissima and A. macrospora.     

Effect of Coronatine on AsA-GSH Cycle of Cotton Seedling under Low Temperature Stress

[Objective] In order to explore the stress-resistant mechanism of coronatine, an indoor experiment was conducted to study the effect of coronatine on ascorbate-glutathione circulatory system of the vegetative organs of cotton seedling under low temperature stress. [Method] Xinluzao 57 was used as the experimental material, when the seedlings reached the two-leaf stage, they were treated at 25 ℃ and 4 ℃ after spraying water, marked as CK and LT; the same treatment was conducted after spraying 0.01 μmol·L^－1 coronatine, marked as COR and (LT+COR). After 1 d of treatment, the roots, stems and leaves of cotton seedling were collected to determine the antioxidant contents and antioxidant enzyme activities. [Result] Compared with the control treatment (CK), the APX, MDHAR activities and DHA, GSH, glutathione contents decreased, the GPX activity, AsA and ascorbate contents increased, and no significant effect on DHAR and GR activities were observed in roots, stems and leaves of cotton seedling after spraying water at low temperature (LT), while in leaves, the GSSG content decreased, AsA-DHA ratio and GSH-GSSG ratio showed the maximum increase. Compared with the LT treatment, spraying COR at low temperature (LT+COR) showed increased APX, MDHAR, DHAR, GPX, GR activities and AsA, DHA, GSH, ascorbate contents; glutathione content in roots, stems and leaves of cotton seedling, and GSSG content, AsA-DHA ratio and GSH-GSSG ratio obviously changed in leaves. [Conclusion] Spraying COR at low temperature could regulate the AsA-GSH metabolism and alleviate the damage caused by low temperature to cotton seedling. COR had the strongest relieving effect on seedling leaves.     

The Effect of Spraying Concentrated Biogas on Growth and Physiological Characteristics of Cotton Seedling

[Objective] The effect of concentrated biogas slurry on growth and physiological characteristics of cotton seedlings was studied in this experiment, and theoretical basis for the rational application of concentrated biogas slurry was provided. [Method] Potted cotton seedlings was sprayed by five different dosages of concentrated biogas slurry, the impact of different spraying quantity (163 mL·hm^－2, 326 mL·hm^－2, 489 mL·hm^－2, 668 mL·hm^－2, 815 mL·hm^－2) after spraying time (after spraying 2nd day, 4th day, 6th day) on cotton seedlings growth and physiological indexes were studied. [Results] The results showed that the suitable quantity of spraying of concentrated biogas slurry had promoting effect to the cotton growth and development, the excess concentrated biogas slurry could inhibit the growth of cotton seedlings. The plant height, dry weight per plant and leaf area of spraying 489 mL·hm^－2 processing are the highest, the average of two batches on the 6th day after spraying are 21.15%, 35.95%, 18.84% higher than CK, respectively. Spraying concentrated biogas slurry can improve cotton seedlings chlorophyll content, soluble sugar contents, soluble protein content. Spraying 489 mL·hm^－2 processing is the highest in both batches, the average of two batches is 18.84%, 24.03%, 3.16% higher than CK, respectively. The result of concentrated biogas slurry onseedlings leaves took effect quickly, especially in 0～4th days. [Conclusion] It is concluded that the suitable amount of concentrated biogas slurry has a positive effect on the growth and physiological characteristics of cotton seedlings, which is beneficial to the formation of strong seedlings of cotton and provides the basis for the later growth of cotton.     

细极链格孢菌蛋白激发子对棉花生长相关酶活性的影响

细极链格孢菌蛋白激发子是一种能诱导植物获得系统抗病性的新型蛋白激发子。在湘杂棉3号的主要生育期,用细极链格孢菌蛋白激发子(PEAT)蛋白粗提液进行叶面喷施后,对棉花叶片中酶保护系统的变化进行了研究。结果表明,经细极链格孢菌蛋白激发子诱导后,棉花叶片POD、SOD、NR的活性与C/N比对照显著增加,而MDA含量比对照显著减少。这可能是PEAT影响棉花细胞内微环境的氧化、还原状态激发植株体内酶保护系统,激活植物自身防卫系统与生长系统,从而使棉花产生对病虫害的抗性,促进了植株生长。     

菊科植物链格孢菌分类研究进展

为明确菊科植物链格孢菌的危害及种类。本研究通过查阅、整理、分析国内外近十年的相关文献资料发现,链格孢菌可侵染多个属的菊科植物的叶、茎和花等,引起黑斑病、褐斑病和轮斑病,发生日趋严重。全世界已报道的以菊科植物为寄主的链格孢菌共54 个种类,国外已报道46 个种类,中国已报道20 个种类。本研究综述了全世界菊科植物链格孢菌的种类,为该类病害的防治研究奠定了基础。中国已报道的菊科植物链格孢菌多集中在北部,种类相对较少,且分类研究主要依靠形态学,应结合分子学方法进行系统学研究。     

链格孢菌蛋白激发子对棉花主要性状及相关酶变化的研究

 研究了链格孢菌蛋白激发子粗提蛋白液对棉花主要性状及相关酶变化的影响。结果表明,链格孢菌蛋白激发子诱导后,显著提高了棉花成铃数且不同程度提高了株高、铃重、衣指、子指和衣分,降低了铃壳重,促进棉花早熟,获得了较好的产量。以浸种处理的子、皮棉产量最高,分别达到3800.6 kg·hm^-2、1598.2 kg·hm^-2,比对照提高了22.15%、26.11%;从纤维品质来看,适时适度喷施棉株,纤维各个指标得到了明显的改善,尤以浸种＋现蕾期喷雾处理的综合值最高,比对照提高了6.1%;从生理生化活性来分析,链格孢菌蛋白激发子诱导后POD、NR、SOD活性及MDA含量均有不同程度的变化,POD、NR及SOD活性增强,而MDH活性降低。在此基础上对链格孢菌蛋白激发子诱导棉株生长及提高棉纤维品种的可能机制作了\{探讨。     

不同喷施浓度的百泰对棉花叶绿素、养分含量的影响

为了研究百泰不同喷施浓度对棉花叶绿素、养分含量的影响,笔者采用不同浓度梯度的百泰于棉花初花期和花铃期进行喷施,并于喷药后测定全株及根、茎、叶中全氮、全磷、全钾含量和棉花功能叶叶绿素含量（SPAD值）。结果表明：适当浓度(450~750 g/hm2)喷施对叶绿素积累及根、茎中全氮、全磷含量具有显著促进作用,但会降低棉花叶片中全氮含量;不论是棉花根系、茎秆还是叶片中,不同浓度间百泰喷施对全钾含量差异不显著;过量喷施(1050 g/hm2)与清水处理间对养分差异不显著。一定浓度的百泰在棉花生长中后期可以促进叶绿素的积累和氮、磷元素的吸收,达到以药促肥的效果。     

砀山梨黑斑病分子检测技术研究

黑斑病是砀山梨上最重要的病害之一,建立一套砀山梨黑斑病的分子检测技术对该病害的早期及时防治及口岸检验检疫具有重要的意义。本研究通过分析比较砀山梨黑斑病菌与其他19种不同真菌的ITS序列,设计了1对特异性引物,能够从该病菌中特异性地扩增出1条398 bp的条带,而其他测试真菌中不能扩增出该条带。在灵敏度检测中,该菌的基因组DNA检出限为10 pg/μL,同时在发病的砀山梨果实组织样品和接种梨黑斑病菌的梨果实组织样品中检测出梨黑斑病菌。因此,可以将该对引物用于梨黑斑病早期诊断及病菌的PCR检测,为指导果农及时进行药剂防治提供有效的技术支撑。     

苹果斑点落叶病研究

对北京地区苹果斑点落叶病研究得出,病原菌Alternaria mali Roberts强毒菌系是苹果斑点落叶病严重发生的主要原因.各果园病原菌强毒菌系发生率和致病性有差异.室内毒力测定和田间药剂防治试验结果表明,50%扑海因、70%代森锰锌、1.5%多抗霉素和10%宝丽安均有很好的抑菌效果.多抗霉素和宝丽安加入1%硼酸可以显著提高药效,并且硼酸本身对菌落生长有一定抑制作用.提出“重点保护春梢叶片,兼顾秋梢叶片”的防病原则.     

棉铃疫病人工接种方法优化及应用

【目的】棉铃疫病是严重危害棉花生产的铃部病害。本研究旨在优化棉铃疫菌(苎麻疫霉,Phytophthora boehmeriae)的人工接种方法并有效应用。【方法】在室内保湿培养条件下,比较了棉株不同部位健康成铃自身携带棉铃疫菌的情况;利用贴接棉铃疫菌菌盘的方法,比较了棉铃表面消毒和不消毒、有伤和无伤接种对棉铃疫病发病情况的影响;建立棉铃疫病人工接种方法并应用于防治棉铃疫病化学药剂筛选、棉花品种抗病性鉴定和棉铃疫菌致病力检测。【结果】田间棉株下部第1~3果枝铃的棉铃疫病发病率显著高于中部第4~6果枝铃、中部第7~9果枝铃和上部第10~12果枝铃;75%(体积分数,下同)酒精浸泡棉铃2 min能够有效杀死棉铃表面携带的棉铃疫菌和其他真菌等杂菌;有伤接种棉铃疫菌,棉铃疫病发病快且均匀。建立了棉铃疫病快速人工接种方法:选取棉株中部第4~9果枝上的健康带柄成铃,去掉苞叶,用75%酒精浸泡消毒2 min,在棉铃中上部铃缝处针刺接种棉铃疫菌,25℃保湿培养3~7 d即可完全发病。应用优化的棉铃疫病人工接种方法筛选、鉴定结果表明,12种化学杀卵菌剂中,对棉铃疫病防效理想的药剂为25%(质量分数,下同)甲霜·霜霉威可湿性粉剂、70%丙森锌可湿性粉剂和52.5%噁酮·霜脲氰水分散粒剂;16个棉花品种对棉铃疫病存在抗性差异;10个棉铃疫菌菌株中JP18-4的致病力最强,JP15-2对棉铃的致病力最弱。【结论】本研究优化建立了棉铃疫病人工接种方法。该方法在7 d内即可完成棉铃疫病相关试验的评价,为加快棉铃疫病防治药剂筛选、棉花品种抗病性鉴定和棉铃疫菌致病力检测提供可行的技术。     

Induction of Defense Enzymes and Control Effect of Endogenous and Rhizosphere Bacteria on Verticillium Wilt of Cotton

[Objective] The colonization in soil, promoting cotton growth effects, inducing resistance of cotton and controlling effects to cotton Verticillium wilt of Bacillus vanillea SMT-24, B. velezensis BHZ-29, B. subtilis SHT-15 and B. atrophaeus SHZ-24 were studied in this paper, which provides a scientific basis for better control of cotton Verticillium wilt. [Method] The antagonistic resistance of these bacteria to Verticillium dahliae was judged by observing the inhibition zone; the number of colonization in the rhizosphere soil was tested to represent the colonization ability of antagonistic bacteria; the growth promoting effect of strains on cotton was determined by analyzing cotton plant height, root length, root hair number and number of leaves; the effect of antagonistic strains on cotton induced resistance was explored by determining catalase (CAT), superoxide dismutase (SOD), phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), and peroxidase (POD) activities in cotton leaves, and investigating the disease index of cotton after inoculation with antagonistic bacteria solutions. [Result] SMT-24, BHZ-29, SHT-15 and SHZ-24 strains significantly inhibited the growth of V. dahliae and formed a clear zone of inhibition. After 2 to 22 days of the third inoculation, these strains of bacteria could survive in the root soil, increase the plant height, leaf number, and root hair number of cotton plants, as well as the activities of cotton CAT, SOD, PAL and POD enzymes, but reduced the disease index. [Conclusion] SMT-24, BHZ-29, SHT-15 and SHZ-24 strains can promote cotton growth, increase the activities of some related defense enzymes, and effectively control cotton Verticillium wilt.     

不同土壤水分条件下棉花库源比变化对产量形成的调节效应

在新疆气候生态条件下,以不同叶型棉花品种为材料,设置不同土壤水分处理,采用人工减源疏库的方法,研究不同土壤水分条件下库源比变化对棉花产量形成的影响。结果表明,中叶型品种新陆早13号在中水(控制0～60 cm土壤相对含水量的下限为田间持水量的70%～75%)条件下,叶源轻度胁迫显著增强剩余叶片光合能力,但光合物质累积量及向生殖器官的分配率和单株结铃数、铃重均未发生明显变化,子棉产量与对照无明显差异;鸡脚叶型品种标杂A1在高水(控制0～60 cm土壤相对含水量的下限为田间持水量的85%～90%)条件下,库容轻度胁迫后叶片光合速率和光合物质累积量与对照无明显差异,但光合产物向蕾铃的分配加快,铃重增大,子棉产量有所增加;小叶型品种新陆早10号减源或疏库后子棉产量均显著低于对照。因此,依据不同类型棉花源库关系对土壤水分的响应不同,通过棉田水分管理对源库进行调节,建立合理的库源比,可进一步提高水分利用效率和棉花产量。     

白三叶草一种叶斑病病原菌的分离鉴定

明确在山东省聊城市白三叶草上发现的一种叶斑病的病原菌,以期为该病害的防控提供参考.2019年采集山东省聊城市东昌府区具有叶斑病的白三叶叶片,利用组织分离法分离病原菌,并依据柯赫式法则验证致病性.在形态学观察的基础上,对病原菌进行分子生物学鉴定,构建系统发育树,分析其遗传多样性.从发病叶片中分离得到病原菌(标记为SY1)...     

脱叶剂对棉花叶片叶绿素荧光动力学参数的影响

利用叶绿素荧光动力学测定技术,对脱叶剂的不同喷施时间条件下棉花叶片光能吸收、传递、转换特性及棉花产量进行了研究。结果表明喷施脱叶剂降低了棉花叶片的光合功能,降低了最大光化学效率(Maximum photochemical efficiency,Fv/Fm)及PSⅡ反应中心开放部分的比例,使初始荧光(Minimal fluorescence,Fo)上升、光合电子传递速率(Electron transport rate,ETR)和PSⅡ总的光化学量子产量(Photosynthetic quantum yield,Yield)降低,提高了非光化学猝灭系数(Non-radiant energy,NPQ),说明脱叶剂胁迫下棉花叶片发生了光抑制,PSⅡ复合体受到损伤伴随着光合电子传递受阻。吐絮率10%时喷施脱叶剂使棉花铃重、衣分、皮棉产量显著低于对照。吐絮率50%时喷施脱吐隆300 g·hm~(-2)+40%乙烯利1200 m L·hm~(-2),第25天棉花脱叶率为90.1%,吐絮率为99.87%,对棉花铃重、衣分及皮棉产量影响最小且更有利于促进叶片脱落和棉铃成熟。     

威灵仙黑斑病的病原鉴定及防治药剂的离体活性筛选

为明确威灵仙黑斑病的致病菌并筛选出有效的防治药剂,采用形态特征及菌株的ITS序列分析方法进行病原菌鉴定,通过平皿菌丝生长抑制法测定杀菌活性,结果表明威灵仙黑斑病病原菌为Alternaria alternata (Fr.)Keissler;25%溴菌腈可湿性粉剂、72%霜疫力克可湿性粉剂、30%爱苗乳油、80%绿亨2号可湿性粉剂和10%世高水分散粒剂对菌丝抑制率均达90％以上。此研究结果可为该病害的有效控制提供前期研究基础。     

Effects of Verticillum Wilt on Leaf Microstructure,Photosynthesis of Cotton

[Objective] The purpose of this study was to determine the change of microstructure and photosynthetic characteristics in cotton leaves under different disease index levels (b0～b4)．[Method] Through investigation and sampling in cotton fields, five treatments were designed based on disease index levels of cotton leaf, and the leaf photosynthesis was tested by WFS-3000 and microstructure was observed with Microscope ECLIPSE Ni-E. [Result] With the increase in disease index levels, cotton leaf gradually lost green color, serious necrosis area occurred, with the leaf withered up till dried to death. The stomata of disease leaf incurred abnormally, increasing intercellular space in mesophyll tissue. Total thickness, upper and lower epidermis thickness, palisade tissue thickness and spongy tissue thickness all decreased significantly among all treatments; the trend showed as followed: total thickness was b0>b1>b2>b3>b4, upper epidermis thickness was b0>b1>b2>b3, lower epidermis thickness, palisade and spongy tissue thickness were consistent as b0>b1>b2. As a whole leaf of total thickness, upper, lower epidermis thickness, palisade and spongy tissue thickness were very significantly negatively correlated with leaf disease index levels, The correlation coefficient reached -0.6. The net photosynthesis rate, transpiration rate, stomata conductance gradually decreased and reached significant different with b0, leaf temperature increased, internal CO₂ first went up then down but no significant difference with b0. [Conclusion] The results indicated that Verticillum wilt damaged leaf microstructure and impaired photosynthesis of cotton leaf.     

Mechanism of Verticillium Wilt Stress Affecting Photosynthetic Characteristics and Chlorophyll Fluorescence Characteristics of Cotton Seedlings

[Objective] The goal of this experiment was to study the effects of Verticillium wilt on photosynthetic characteristics and chlorophyll fluorescence characteristics of cotton seedlings, and to provide a theoretical basis for the identification of cotton resistance to Verticillium wilt at the seedling stage and the establishment of Verticillium wilt control techniques. [Method] Zhongzhimian 2 (Verticillium wilt resistant cultivar, ZZM-2) and Jimian 11 (Verticillium wilt susceptible cultivar, JM-11) were selected. Verticillium dahliae was inoculated at the two true leaves stage. The photosynthetic and chlorophyll fluorescence parameters of the last fully expanded young leaves were measured at 6 d after inoculation. [Result] (1) Under the stress of Verticillium wilt, the leaf area per plant, leaf water potential, photosynthetic pigment content and net photosynthetic rate (Pn) of cotton seedlings decreased, and the decreases in ZZM-2 were smaller than those in JM-11. (2) The decreased intercellular CO2 concentration and increased stomatal limitation value in the two test materials indicated that the decrease in Pn was mainly caused by stomatal limitation, and the decrease in chlorophyll a in ZZM-2 was smaller than the decrease in chlorophyll b, whereas the opposite trend was observed in JM-11. (3) The light response curve parameters of ZZM-2 were increased and theCO₂ response curve parameters of ZZM-2 were decreased, but all parameters in JM-11 were decreased. For ZZM-2, the potential photochemical efficiency (F_v/F_m), the quantum yield of regulated energy dissipation (Y_NPQ) and the quantum yield of non-regulated energy dissipation (Y_NO) were increased slightly and the actual photochemical efficiency (Y_II) was decreased slightly, but the differences in these four indexes between diseased plants and healthy plants was not significant; however, the variable fluorescence yield (F_v) was significantly decreased. For JM-11, F_v, Fv/F_m, Y_II and Y_NPQ were significantly decreased, and Y_NO was significantly increased. (4) F_v/F_m in leaf lesion sites decreased, but that in non-lesion sites did not decline or even showed a slight increase. [Conclusion] Verticillium wilt resistant cultivars with higher photosynthetic capacity and carbon assimilation ability could reduce the effects of Verticillium wilt on photosynthetic characteristics and reduce the impacts on cotton yield and quality.     

芦荟黑斑病发生规律及室内药剂筛选

为了解芦荟黑斑病的发生规律,进一步为防治提供理论依据。该文对三种越冬形式的病原菌分别采用直接镜检、组织分离法及致病性测定对芦荟黑斑病菌（Alternaria obpyriformis T. Y. Zhang）进行了越冬场所和越冬方式的研究。通过针刺法、涂抹法及玻片粘着法确定病菌侵入和传播途径。人工接种条件下测定了病菌对5科10种植物的侵染能力。采用孢子萌发法和菌丝生长速率法对病菌进行室内药剂筛选。结果表明,病原菌可在病残体上以菌丝和分生孢子越冬,通过气孔和伤口侵入寄主,分生孢子能借助气流传播;人工接种时能侵染豆科、十字花科的部分植物。供试的7种药剂对病菌菌丝生长和孢子萌发都有显著的抑制作用,其中施保功可湿性粉剂对其病菌的菌丝体抑制效果最好,抑菌率达84.24%;扑海因悬浮剂对分生孢子萌发抑制效果最佳,抑制率为67.44%。     

河南省芝麻主要病害综合治理研究

明确了河南省芝麻主要病害——苗病、病毒病、茎点枯病和叶斑病的发生危害及田间流行动态;试验筛选出抗病品种,复方多菌灵防治苗病、茎点枯病、叶斑病和40％氧化乐果治蚜防病毒病。据此提出以抗病品种为基础,药剂防治为保证的防治策略,制定出多种病害综合防治技术。经多点试验及示范推广,防病增产效果显著。