Inhibitory Effects of Extracts from Marigold(Tagetes patula) against Tomato Fusarium Wilt

[ Objective ] The study aimed to explore a new way for the control of Tomato Fusarium Wilt. [ Method ] Different solvents were used to prepare the ex-tracts of marigold, and the inhibitory effects of different extraction solvents and different extraction parts of marigold against Tomato Fusar/um Wilt were compared. [ Result ] Among different solvent extracts of marigold, chloroform extracts had the strongest inhibitory effects against the growth of the pathogen; among the chloro- form extracts from different parts of marigold, root extract had the most obvious inhibitory effect against the disease, followed by flower and leaf extracts, and the in- hibitory effect of stem extract was the weakest. [ Conclusion ] The active components of marigold have inhibitory effect against Tomato Fusarium Wilt, and the plant has good development prospects and application value.

A study on the pathogen species and physiological races of tomato Fusarium wilt in Shanxi,China

In order to clarify the main pathogens of tomato Fusarium wilt in Shanxi Province, China, morphological identification, elongation factor 1 alpha （EF-1α） sequence analysis, specific primer amplification and pathogenicity tests were applied to study the isolates which were recovered from diseased plants collected from 17 different districts of Shanxi Province. The results were as follows： 1） Through morphological and molecular identification, the following 7 species of Fusarium were identified： F. oxysporum, F. solani, F. verticillioides, F. subglutinans, F. chlamydosporum, F. sporotrichioides, and F. semitectum; 2） 56 isolates of F. oxysporum were identified using specific primer amplification, among which, 29, 5 and 6 isolates were respectively identified as F. oxysporum f. sp. lycopersici physiological race 1, race 2, and race 3; 3） pathogenicity test indicated the significant pathogenicity of F. oxysporum, F. solani, F. verticillioides, and F. subglutinans to tomato plant. Therefore, among these 4 species confirmed as pathogenic to tomato in Shanxi, the highest isolation rate （53.3％） corresponded to F. oxysporum. Three physiological species, race 1, race 2, and race 3 of F. oxysporum f. sp. lycopersici are detected in Shanxi, among which race 1 is the most widespread pathogen and is also considered as the predominant race.

Population structure and association mapping to detect QTL controlling tomato spotted wilt virus resistance in cultivated peanuts

Tomato spotted wilt(TSW)is a serious virus disease of peanut in the United States.Breeding for TSWV resistance would be facilitated by the implementation of marker-assisted selection in breeding programs;however,genes associated with resistance have not been identified.Association mapping is a type of genetic mapping that can exploit relationships between markers and traits in many lineages.The objectives of this study were to examine genetic diversity and population structure in the U.S.peanut mini-core collection using simple sequence repeat(SSR)markers,and to conduct association mapping between SSR markers and TSWV resistance in cultivated peanuts.One hundred and thirty-three SSR markers were used for genotyping 104 accessions.Four subpopulations,generally corresponding to botanical varieties,were classified by population structure analysis.Association mapping analysis indicated that five markers:pP GPseq5D5,GM1135,GM1991,TC23C08,and TC24C06,were consistently associated with TSW resistance by the Q,PCA,Q+K,and PCA+K models.These markers together explained 36.4%of the phenotypic variance.Moreover,pP GPseq5D5 and GM1991 were associated with both visual symptoms of TSWV and ELISA values with a high R^2.The potential of these markers for use in a marker-assisted selection program to breed peanut for resistance to TSWV is discussed.

Integrative analysis of the transcriptome and metabolome reveals the response mechanism to tomato spotted wilt virus

Tomato spotted wilt virus(TSWV)is an important virus that has rapidly spread throughout the world.TSWV seriously hinders the production of tomato(Solanum lycopersicum)and other plants.In order to discover more new genes and metabolites related to TSWV resistance in tomato plants,the genes and metabolites related to the resistance of tomato plants inoculated with TSWV were identified and studied herein.The tomato TSWV-resistance line YNAU335(335)and TSWV-susceptible lines NO5 and 96172I(961)were used as the transcriptome and metabolome research materials.Transcriptomic and metabolomic techniques were used to analyze the gene and metabolite response mechanisms to TSWV inoculation.A total of 3566,2951,and 2674 differentially expressed genes(DEGs)were identified in lines 335,NO5,and961,respectively.Meanwhile,208,228,and 273 differentially accumulated metabolites(DAMs)were identified in lines 335,NO5,and 961,respectively.In line 335,the number of DEGs was the highest,but the number of DAMs was lowest.Furthermore,903 DEGs and 94 DAMs were common to the response to TSWV in the three inbred lines.The 903 DEGs and 94 DAMs were mainly enriched in the plant hormone signal transduction and flavonoid synthesis pathways.In addition,many nucleotide-binding site-leucine-rich repeat genes and transcription factors were found that might be involved in the TSWV response.These results provide new insights into TSWV resistance mechanisms.

Effect of Fertilization on Tomato Bacterial Wilt Biocontrolling and Soil Health Restoration Using FAME Analysis

The effect of applying biological organic fertilizer(BOF)on bacterial wilt incidence of tomato and soil microbial community under continuous cropping was studied. The results showed that all the tomatoes were infected by bacterial wilt in the control. The infection rates of tomatoes in the treatments with un-composted BOF and decomposed BOF were 55 and 50% respectively. Fatty acid methyl esters(FAME)analysis indicated soil microbial community changed sensitively after applying BOF. Soil FAME total content, relative fungi content and ratio of fungi to bacteria were significantly increased in both BOF treatments. The soil odd-number fatty acid proportion changed after applying BOF, aC15 : 0, iC17 : 0 decreased, while cyC17 : 0 increased in soil odd-number fatty acid proportion. BOF application would strengthen soil health and disease suppression. The content of C16 : 1 11c in soil microbial community was obviously increased after decomposed BOF application. It indicated that the growth of AM fungi could be enhanced with decomposed BOF application. FAME microbial biomarkers could be used for an indicator of soil health and disease suppression. Odd-number fatty acid proportion was a sensitive indicator of the effect of applying un-composted and decomposed BOF respectively on soil health regulating.

香葱伴生番茄对青枯病及根际微生态特征的影响

【目的】为明确香葱伴生对番茄青枯病及根际微生态特征的影响,揭示香葱伴生番茄降低青枯病发病率的机理。【方法】通过田间试验设置番茄单作和香葱伴生番茄2个处理,分别采集单作发病番茄(QK)、单作健康番茄(NBS)和香葱伴生番茄(BS)的根际土壤,应用16S rDNA高通量测序和液相色谱-质谱联用(LC-MS)技术,探究香葱伴生对番茄根际微生态特征的影响。【结果】田间试验结果表明,番茄单作处理和香葱伴生番茄处理的青枯病平均病株率分别为50.48、31.43%,香葱伴生番茄处理对番茄青枯病的防治效果为37.74%。16S rDNA高通量测序结果表明,BS、NBS根际土壤细菌群落相对丰度和多样性均显著高于QK;与QK相比,BS和NBS根际土壤细菌茄科雷尔氏菌属相对丰度显著降低,而芽孢杆菌属相对丰度升高;与NBS相比,BS根际土壤细菌茄科雷尔氏菌属相对丰度降低,芽孢杆菌属相对丰度显著提高。利用LC-MS技术共鉴定出番茄根际土壤代谢物586种,其中正离子模式代谢物320种,负离子模式代谢物266种,并将代谢物的功能注释至新陈代谢、遗传信息加工和环境信息加工等代谢通路;与NBS相比,BS根际土壤代谢物中的缬氨酸、L-天冬酰胺和柠檬酸的含量均显著降低,L-赖氨酸、谷氨酸、D-谷氨酰胺和异亮氨酸的含量也低于NBS,但差异未达到显著水平。【结论】香葱伴生番茄显著降低番茄青枯病田间发病率,改变了番茄根际土壤中细菌群落结构和番茄根际土壤代谢物含量。

Identification of a SSR marker (TOM-144) linked to Fusarium wilt resistance in <i>Solanum lycopersicum</i>

With the discovery of molecular markers and marker assisted selection technology, the research has entered into a new era and has made it possible to develop new and more informative PCR-based markers, including SSR, and to further facilitate the use of markers in tomato breeding. The present study is a step to introduce a new SSR marker (TOM-144) which was deduced after evaluation of eight microsatellite loci amongst the twenty-one different tomato cultivars. The marker selected was inherited and segregated in mendelian fashion as demonstrated in successive generation of a cross between parent cvs. H-24 x GT-2.

青蒿中番茄斑萎病毒和烟草花叶病毒的分子鉴定及相关序列分析

番茄斑萎病毒(tomato spotted wilt virus, TSWV)和烟草花叶病毒(tobacco mosaic virus, TMV)是2种重要的植物病原病毒,对多种经济作物的产量和品质均造成严重影响。2021年-2022年,在云南省丽江市烟草种植区不同烟区采集叶片黄化、皱缩以及无症状的青蒿Artemisia caruifolia样品共计14份,利用免疫金标速测卡和RT-PCR对其病原病毒进行检测。利用免疫金标速测卡检测结果显示,在所检样品中有9份样品检测出TSWV,检出率为64.28%,有3份样品检测出TMV,检出率为21.43%,2种病毒复合侵染的检出率同样为21.43%;利用RT-PCR对复合侵染的3份样品进行分子检测,结果显示,在3份复合侵染青蒿样品中获得3条TSWV N基因序列、3条TMV cp基因序列和2条TMV RdRp部分序列。TSWV青蒿分离物与分离自云南的TSWV-2分离物相似性最高,为99.6%;TMV青蒿分离物与分离自辽宁的TMV-Shenyang分离物和分离自云南的TMV-Yongren-1相似性最高,均大于99.4%。这是首次发现TSWV和TMV 2种不同属病毒复合侵染青蒿。

绿农林^(®)41复合微生物菌肥对番茄枯萎病发生和根际土壤 真菌群落的影响

探究绿农林^(®)复合微生物菌肥、番茄枯萎病发生和土壤真菌群落结构的关系,为合理应用微生物制剂绿色防控番茄枯萎病提供理论依据。以往年番茄枯萎病严重发生地块为试验地,分别设置4个处理,清水对照(CK)、绿农林^(®)41复合微生物菌肥(LNL41)、菌肥营养基质(NS)和复合微生物(CM),测定根际土壤养分含量、植株生长、土壤呼吸速率、枯萎病发病率;采用18S rDNA测序技术,探究施用LNL41条件下番茄枯萎病发生及根际土壤真菌群落结构的差异。结果表明:各处理中以LNL41处理效果最显著。LNL41和CM处理的番茄根际土壤中有机质和速效磷含量显著高于其他处理;与对照比较,LNL41、CM和NS处理的株高、茎围、叶面积、光合作用、叶绿素、产量和水溶性糖增幅分别达8.87%~34.71%、15.93%~67.62%、13.37%~52.88%、3.17%~12.55%、3.20%~20.49%、4.38%~19.53%、0.46%~8.79%;LNL41处理的采收期番茄根系土壤呼吸速率提高59.52%,不同生长期的发病率达2.33%~16.33%,防效达80.50%~90.83%;根际土壤真菌属水平Ace指数和Chao1指数分别提高了26.97%~57.71%、24.89%~56.00%,CM处理的多样性指标Simpson指数和Shannon指数明显提高了25.75%~29.45%、39.04%~49.13%,而NS处理的多样性指标有所下降;LNL41处理的肉座菌科和木霉属分别为排名前5的优势科和属(丰度均为8.56%);4个处理中Trichoderma分别与Cladosporium、Uwebraunia、Aureobasidium和Fusarium丰度相似,与Aspergillus和Alternaria呈正相关。LNL41处理的Chao1指数与有机质、速效磷、速效钾和土壤呼吸速率呈显著正相关关系,与盐度和发病率呈显著负相关关系。LNL41处理的腐生营养型功能类群丰度增加了0.92~11.15个百分点,plant pathogen下降了2.55个百分点,endophyte下降了7.95个百分点,而施用NS和CM的处理只有2个功能类群丰度上升。LNL41能显著改善土壤养分比例,进而改善土壤真菌群落结构和功能特性,激发真菌群落腐生营养型功能,促进番茄生长,减少枯萎病的发病率。

Insect and Diseases Resistance in Tomato Entries

The study was conducted with 75 tomato entries at the farm of Olericulture Division, Horticulture Research Centre (HRC), Bangladesh Agricultural Research Institute (BARI), Gazipur, Bangladesh during the winter season of 2020-21 to evaluate insect and disease reaction. Among the various insect and diseases of tomatoes, the late blight, TYLCV, bacterial wilt infection and leaf miner, fruit borer infestation are most common in Bangladesh. The TYLCV infection was observed 0% to 27% infection, while 47 entries showed zero percent infection. The range of bacterial wilt infection was 0% to 10% and zero percent infection was observed in 62 entries. In case of leaf miner infestation and fruit borer infestation, the range was 0% to 43% and 0% to 10%, respectively. Considering tolerance to late blight, TYLCV, bacterial wilt infection and leaf miner, fruit borer infestation, fruit size, fruit shape, plant growth nature, cluster nature of fruit, type of fruit ten entries AVTO 1010, AVTO 1706, AVTO 1713, AVTO 1829, AVTO 1909, AVTO 1911, AVTO 1915, AVTO 1921, AVTO 1954 and SLA 011 were found zero percent late blight, TYLCV, bacterial wilt infection and leaf miner, fruit borer infestation. So, these ten entries can be selected for disease and insect tolerant tomato varieties development as well as developing disease and insect tolerant hybrid tomato varieties.

Influence of Seedling Age on the Susceptibility of Tomato Plants to <i>Ralstonia solanacearum</i>during Protray Screening and at Transplanting

The study was undertaken to assess whether seedling age played any role in governing the vulnerability of tomato to the bacterial wilt pathogen, Ralstonia solanacearum, based on the preliminary observations that the extent of mortality during seedling-stage screening was relatively less in older seedlings. Employing the virulent strain ‘NH-Av01’ isolated from tomato, 2-, 3-, 4- or 5-week-old seedlings of susceptible ‘Arka Vikas’ raised in organic cocopeat in 98 cavity protrays were inoculated with the pathogen through root-injury inoculation approach. Disease symptoms appeared earlier and with more severity in 2-week-old seedlings followed by 3-, 4- and 5-week-old saplings recording 74%, 68%, 63% and 49% mortality, respectively, after four weeks of inoculation suggesting that older the seedlings, less the susceptibility to the pathogen. The growth characteristics of seedlings (shoot height, shoot and root weights) showed a significant increase with seedling age (0.21, 0.54, 1.14 and 2.09 g gross weight/seedling at 2, 3, 4 and 5 weeks, respectively) indicating healthier saplings with delay in inoculation time. In subsequent trials, seedlings of 3, 4, 5 or 6 weeks were transplanted to field-sick soil in protrays or in pots with monitoring for 1 - 4 months which indicated a significant reduction in disease incidence and severity with increase in seedling age. The observations suggested that seedling age should be considered as a major factor influencing the susceptibility of tomato seedlings to R. solanacearum with the chances of variations in the extent of disease incidence or inconsistent results during seedling-stage screening and the possibility of escapes with older seedlings. Two-week seedlings formed the best when the aim is to induce maximum disease incidence, while transplanting at 5 - 6 weeks stage appeared the best when the objective is minimal disease incidence or formulating disease management strategies.

三株无量山森林土壤芽孢杆菌鉴定及其生物活性挖掘

【目的】挖掘无量山国家自然保护区潜在的高活性微生物菌株,旨在为农业绿色投入品研发提供高效的菌种资源。【方法】以番茄枯萎病菌(Fusarium oxysporum)为靶标筛选高拮抗活性菌株,观察对菌丝生长的影响,测定对孢子萌发的抑制作用;检测脂肽类化合物合成基因以及菌株体外产酶、解磷、解钾、固氮及产铁载体能力;结合形态学、生理生化特征和16S rRNA、gyrA、rpoB基因进行菌株鉴定,室内盆栽试验验证防病和促生效果。【结果】分离筛选获得153株可培养细菌,其中,菌株SH-53、N4471和N9456抑菌效果分别为92.35%、87.29%和88.47%,能抑制病原菌菌丝生长和分生孢子萌发,且对多种病原菌表现出良好拮抗活性。3株功能菌均具有溶锌、产淀粉酶和蛋白酶的能力,菌株SH-53和N4471还具有解磷、固氮、分泌纤维素酶以及产铁载体能力。3个功能菌基因组中均含有srfA、fenA、ituA、ituC、ituD、bymC等脂肽类化合物合成基因。经鉴定菌株SH-53为解淀粉芽孢杆菌(Bacillus amyloliquefaciens),N4471为卡式芽孢杆菌(B.cabrialesii),N9456为暹罗芽孢杆菌(B.siamensis)。盆栽试验结果表明,3株功能菌防效分别为84.66%、54.96%和59.74%,对番茄幼苗的株高、茎粗、根长等农艺性状均具有较好促进作用。【结论】3个菌株具有高效、广谱的抑菌活性,具有多样化的生物活性,作为高效的微生物资源具有广阔的应用前景。

宁夏地区不同品种番茄主要病毒病的分子鉴定及抗性评价

为明确宁夏地区番茄上的病毒种类并分析复合侵染状况以及评价不同品种番茄的抗病性,于宁夏贺兰园艺产业园采集139份番茄疑似病毒样品(共22个品种),利用主要的8种番茄病毒特异性引物对病样进行RT-PCR分子检测与鉴定。结果显示:在疑似病样中,病毒检出率为98.56%,其中,ToMMV首次在银川市检出,检出率显著高于其他病毒,达92.05%,为当地优势毒源;其次为TSWV和STV检出率分别为76.04%和73.35%;TYLCV、ToCV、ToMV、CMV和TMV检出率较低。通过对番茄病毒的复合侵染现象分析发现,复合侵染的样本占阳性样本数的94.89%,其中3种病毒的复合侵染率占复合侵染总比的53.08%,且3种和4种复合侵染类型繁多。此外,对22个品种感病情况分析,‘冠蔬106’感染的病毒种类最多,为6种,而‘黑小哥’未检测出以上8种番茄病毒。进而对番茄病毒病抗性品种进行初步评估,‘黑小哥’‘千禧’‘香妃9号’‘152’‘冠疏103’‘193’和‘赛硒柿2号’这7个品种为抗病毒品种。综上,面对外来病毒的侵入,复合侵染的暴发,应当引起高度重视和警惕。

番茄青枯病拮抗菌的筛选及防治效果

为了筛选出具有抑制青枯雷尔氏菌作用的拮抗菌,采用形态指标、生理生化特征以及16S rRNA序列分析等方法对菌株进行了研究,并且通过阴性对照(CK)、番茄青枯病菌阳性胁迫处理(RB)和拮抗菌K+番茄青枯病菌处理(KRB)3个盆栽番茄土壤样品进行了防卫反应基因的表达研究.结果表明,拮抗菌K5菌落呈乳白色且表面光滑,经革兰氏染色为阳性,初步确定为芽孢杆菌,通过分子鉴定后确定为贝莱斯芽孢杆菌;番茄青枯病的盆栽防治效果达到23.20%,K5菌株在接种48 h后能诱导番茄根部抗病基因表达,CTR、ETR基因的表达量提高,表明K5通过植物抗病相关基因的表达,能诱导植物产生抗病性,并能有效地抑制青枯病菌的繁殖,从而达到防治青枯病的作用.

抗青枯病番茄砧木新品种勇士3号的选育

勇士3号是以自交系4为母本,以自交系1为父本配制而成的番茄砧木一代杂种。无限生长型,中熟,植株生长势强,根系发达,茎粗2.3~3.3 cm,第1花序着生节位为第7~9节;果实扁圆形,成熟果橙色,单果质量约60 g,每667 m^(2)产量约4000 kg,种子扁平短卵形,表面有茸毛,千粒重约1.9 g;嫁接亲和性好、成活率高,高抗青枯病,适宜广西南部产区作为番茄嫁接砧木。

复合微生物菌肥对番茄青枯病发生和根际土壤细菌群落的影响

【目的】探究复合微生物菌肥与番茄青枯病发生、根际土壤理化性质及土壤细菌群落之间的关系,为合理应用微生物菌肥绿色防控番茄青枯病提供理论依据。【方法】以往年番茄青枯病严重发生地块为试验地,设清水对照(T1)、复合微生物菌肥(T2)、菌肥营养基质(T3)和复合微生物(T4)4个处理,测定番茄根际土壤养分含量、番茄植株生长、根系青枯病菌带菌率、青枯病发病率及根际土壤呼吸速率;采用16S rDNA测序技术分析施用复合微生物菌肥后番茄根际土壤细菌群落结构变化。【结果】在番茄采收期测定结果显示,复合微生物菌肥和复合微生物处理的番茄根际土壤中有机质、铵态氮和速效磷含量均高于或显著(P<0.05)高于其他处理;与清水对照相比,复合微生物菌肥、复合微生物和菌肥营养基质处理的番茄株高、茎围、叶面积、光合作用、叶绿素相对含量(SPAD值)、产量和水溶性糖增幅分别为6.82%~27.88%、19.59%~47.40%、2.04%~17.08%、3.88%~11.21%、1.99%~17.15%、9.13%~22.37%和0.45%~5.12%;复合微生物菌肥处理的番茄根系青枯病菌带菌率降至11.11%,土壤呼吸速率较清水对照提高54.05%;与清水对照相比,复合微生物菌肥、复合微生物和菌肥营养基质处理的番茄根际土壤细菌属水平ACE指数和Chao1指数分别提高3.12%~6.64%和4.76%~7.18%,Simpson指数和Shannon指数无显著差异(P>0.05);复合微生物菌肥处理的芽孢杆菌目(Bacillales)和芽孢杆菌属(Bacillus)分别为排名前10的优势目(8.31%)和优势属(6.60%);4个处理中芽孢杆菌属与Christensenellaceae_R-7_group和WCHB1-32的丰度相似,与WCHB1-32、瘤胃梭菌属(Ruminiclostridium_1)、Christensenellaceae_R-7_group和噬几丁质菌科未培养菌属(uncultured_bacterium_f_Chitinophagaceae)正相关,与假单胞菌属(Pseudomonas)、厌氧绳菌科未培养菌属(uncultured_bacterium_f_Anaerolineaceae)和嗜甲基菌属(Methylophilus)负相关。复合微生物菌肥处理的代谢途径、次生代谢物生物合成、抗生素生物合成和氨基酸生物合成等功能微生物丰度增幅最明显;有机质、速效磷、速效钾、芽孢杆菌属、雷尔氏菌属(Ralstonia)和土壤呼吸速率与抗生素生物合成功能正相关,pH、芽孢杆菌属、雷尔氏菌属和土壤呼吸速率与氨基酸生物合成功能正相关,而盐度和发病率与2项功能负相关。【结论】复合微生物菌肥能显著改良土壤养分比例、改善土壤细菌群落结构和功能特性、提升抗生素生物合成和氨基酸生物合成等功能、促进番茄生长、降低青枯病发病率。复合微生物菌肥500倍稀释液对番茄青枯病的防病促生作用显著,具有良好的应用前景。

烟草番茄斑萎病毒RT-LAMP检测体系的建立及优化

为快速检测烟草番茄斑萎病毒(tomato spotted wilt virus,TSWV),基于TSWV核外壳蛋白(nucleocapsid protein,NP)保守序列设计5组引物进行筛选,采用单一变量法对反应温度、时间及反应体系中dNTPs、Mg^(2+)、甜菜碱的含量和内外引物比等参数进行优化,建立烟草TSWV反转录环介导等温扩增(loop-mediated isothermal amplification,RT-LAMP)检测体系,并采用RT-PCR(revers transcription-polymerase chain reaction)检测方法进行平行比对试验,验证优化后RT-LAMP的特异性、灵敏性及实用性。结果表明,烟草TSWV RT-LAMP检测体系最佳引物组为TS-N-4,在25μL的反应体系中各组分最佳加入量为缓冲液2.5μL、100 mmol·L^(-1) MgSO40.5μL、10 mmol·L^(-1) dNTPs 0.5μL、10 mmol·L^(-1) FIP/BIP 1.5μL、10 mmol·L^(-1) F3/B30.5μL、10 mmol·L^(-1) LF/LB 1.5μL、5 mmol·L^(-1) Betaine 6μL、Bst 2.0 WarmStar DNA Polymerase(8000 U·mL-1)0.5μL、M-MLV酶(10000 U·mL^(-1))0.125μL、RNA(≥64.7 fg)1μL,DEPC H2O补至25μL;最佳反应温度和时间分别为58℃、60 min。优化后的RT-LAMP灵敏度是RT-PCR的1000倍,且田间样品检测结果与RT-PCR相符。建立的RT-LAMP方法特异性强、灵敏度高、操作简单,对于烟草TSWV的检测及监控有重要意义。

基于刺吸电位技术的西花蓟马取食行为研究进展

西花蓟马是一种世界性的重要农业害虫,对蔬菜和花卉等园艺作物的生产构成了巨大威胁,该害虫造成的危害与其取食行为密切相关。刺吸电位技术(EPG)是研究刺吸式和锉吸式口器昆虫取食行为的重要工具,在揭示害虫的取食机制、寄主植物的防御、害虫与寄主植物互作等方面发挥了重要作用。本文综述了西花蓟马取食行为波形的划分、寄主种类、病毒和杀虫剂对西花蓟马取食行为的影响,为西花蓟马的防控奠定了基础。

辣椒抗番茄斑萎病毒研究进展

番茄斑萎病毒属(Tospovirus)是布尼亚病毒科(Bunyaviridae)中唯一能够侵染植物的病毒属,其核心成员番茄斑萎病毒(Tomato spotted wilt virus,TSWV)对全球农业构成了严峻挑战。TSWV作为一种负单链RNA型病毒,主要通过蓟马持久性增殖传播。辣椒受TSWV危害尤为严重,常表现为落叶、新叶黄化畸形、生长点坏死等多种复合症状,造成了巨大的经济损失。近年来,随着生物信息学研究的不断深入和辣椒全基因组测序的完成,研究者对TSWV的致病机理与辣椒抗TSWV机制的研究取得了较好的进展。PCR和逆转录PCR(RT-PCR)技术已被广泛应用于TSWV的精准检测,特别是针对核壳体蛋白基因(N-gene)设计的特异性引物,显著提升了检测效率与准确性。同时,抗性分子标记已广泛应用于TSWV抗性种质资源的检测与鉴定。选育抗病品种是防治TSWV最有效的途径,通过广泛筛选国内外抗性种质资源,并结合分子标记技术,已成功培育出中椒115等抗TSWV辣椒新品种。此外,TSWV还可通过抗原结构变异或宿主免疫抑制等免疫逃逸机制,成功规避植物防御系统,从而加剧防控难度。因此,未来研究需聚焦于抗性遗传资源的深度挖掘、育种技术体系的完善与新型抗性基因的发掘,以培育出更广泛、更持久抗性的辣椒新品种。

番茄斑萎病毒蛋白结构及其抑制剂作用机制研究进展

番茄斑萎病毒(tomato spotted wilt virus,TSWV)基因组可编码RdRp、NSm、NSs、Gc、Gn和N等多种蛋白,目前,相关研究主要集中在植物(番茄和辣椒)对TSWV的抗病基因(Sw-5b和Tsw)所介导的抗性以及药剂对TSWV N蛋白的抑制作用。TSWV蛋白具有作为药剂分子靶标的潜力,但关于TSWV蛋白与药剂的作用机制尚未见系统、全面的研究报道。本文从结构生物学的角度出发,详细介绍了目前已经被解析的TSWV病毒蛋白三维结构,并通过AlphaFold2模型预测了尚未被解析的4种TSWV蛋白结构;同时,综述了TSWV抗性基因和TSWV抑制剂在植物保护领域的研究应用进展。以宁南霉素、盐酸吗啉胍和利巴韦林等药剂为例,分析其可能作用于TSWV蛋白的分子机理,并预测了这些药剂与TSWV蛋白可能的作用位点,旨在为后续深入挖掘和探索新型抗TSWV药剂提供理论依据。