In 2011, common symptoms of grapevine dieback were frequently observed in 2- to 5-year-old table grape (Vitis vinifera L.) cvs. in four vineyards located in northern Tunisia. The symptoms included dead spur and cordons, shoot dieback, and sunken necrotic bark lesions, which progressed into the trunk resulting in the death of large sections of the vine. Longitudinal and transversal sections of cordons and spurs from symptomatic vines revealed brown wedge-shaped cankers of hard consistency. Twelve symptomatic samples from spur and cordons were collected, surface disinfected by dipping into 5% (v/v) sodium hypochlorite for 2 min, and small pieces from the edge of necrotic and healthy tissue were removed and plated onto potato dextrose agar (PDA) at 25°C in the dark. Based on colony and conidia morphological characteristics, isolates were divided in three species, named Diplodia seriata, Botryosphaeria dothidea, and Neofusicoccum luteum. D. seriata colonies were gray-brown with dense aerial mycelium producing brown cylindric to ellipsoid conidia rounded at both ends and averaged 22.4 × 11.7 μm (n = 50). B. dothidea colonies were initially white with abundant aerial mycelium, gradually becoming dark green olivaceous. Conidia were fusiform to fusiform elliptical with a subobtuse apex and averaged 24.8 × 4.7 μm (n = 50). N. luteum colonies were initially pale to colorless, gradually darkening with age and becoming gray to dark gray producing a yellow pigment that diffuses into the agar. Conidia were hyaline, thin-walled, aseptate, fusiform to fusiform elliptical, and averaged 19.8 × 5.5 μm (n = 50). Identity of the different taxa was confirmed by sequence analyses of the internal transcribed spacer (ITS1-5.8S-ITS2) region of the rDNA and part of the elongation factor 1-alpha (EF1-α) gene. BLAST analysis of sequences indicated that six isolates were identified as D. seriata (GenBank: AY259094, AY343353), one isolate as B. dothidea (AY236949, AY786319) and one isolate as N. luteum (AY259091, AY573217). Sequences were deposited in GenBank under accessions from KC178817 to KC178824 and from KF546829 to KF546836 for ITS region and EF1-α gene, respectively. A pathogenicity test was conducted on detached green shoots cv. Italia for the eight Botryosphaeriaceae isolates. Shoots were inoculated by placing a colonized agar plug (5 mm diameter) from the margin of a 7-day-old colony on fresh wound sites made with a sterilized scalpel. Each wound was covered with moisturized cotton and sealed with Parafilm. Control shoots were inoculated using non-colonized PDA plugs. After 6 weeks, discoloration of xylem and phloem and necrosis with average length of 38.8, 17.6, and 11.2 mm were observed from inoculated shoots with D. seriata, N. luteum, and B. dothidea, respectively, and all three fungi were re-isolated from necrotic tissue, satisfying Koch's postulates. Control shoots showed no symptoms of the disease and no fungus was re-isolated. In Tunisia, Botryosphaeria-related dieback was reported only on citrus tree caused by B. ribis (2), on Pinus spp. caused by D. pinea (4), on Quercus spp. caused by D. corticola (3), and on olive tree (Olea europea) caused by D. seriata (1). To our knowledge, this is the first report of D. seriata, B. dothidea, and N. luteum associated with grapevine dieback in Tunisia. References: (1) M. Chattaoui et al. Plant Dis. 96:905, 2012. (2) H. S. Fawcett. Calif. Citrogr. 16:208, 1931. (3) B. T. Linaldeddu et al. J. Plant Pathol. 91:234. 2009. (4) B. T. Linaldeddu et al. Phytopathol. Mediterr. 47:258, 2008.

译文

:2011年,在2至5岁的食用葡萄(Vitis vinifera L.)CVS中经常观察到葡萄枯死的常见症状。在突尼斯北部的四个葡萄园中。症状包括死刺和警戒线,枝条枯死和凹陷的坏死性树皮病变,这些病变发展到树干中,导致大片葡萄藤死亡。有症状藤蔓的警戒线和刺的纵向和横向截面显示出褐色的楔形溃疡,具有坚硬的一致性。收集十二个有刺和带状疱疹的有症状样品,通过浸入5%(v / v)次氯酸钠中2分钟进行表面消毒,并去除坏死和健康组织边缘的小块并将其铺在马铃薯葡萄糖琼脂(PDA)上在黑暗中25°C下。根据菌落和分生孢子的形态特征,将分离物分为三种,分别为Diplodia seriata,Botryosphaeria dothidea和Neofusicoccum luteum。 D. seriata菌落为灰褐色,具浓密的气生菌丝体,产生棕色圆柱形到椭圆形分生孢子,两端圆形,平均22.4×11.7μm(n = 50)。 B. dothidea菌落最初是白色的,具丰富的气生菌丝体,逐渐变为深绿色的橄榄色。分生孢子为梭形到梭形椭圆形,先端圆形,平均24.8×4.7μm(n = 50)。黄体猪笼草的菌落最初为浅色至无色,随着年龄的增长逐渐变暗,从灰色变为深灰色,产生黄色颜料,其扩散到琼脂中。分生孢子是透明的,卵形的,椭圆形的,梭形到梭形椭圆形的分生孢子,平均为19.8×5.5μm(n = 50)。通过对rDNA的内部转录间隔区(ITS1-5.8S-ITS2)区和部分延伸因子1-alpha(EF1-α)基因进行序列分析,确认了不同分类单元的身份。序列的BLAST分析表明,鉴定出六种分离株为D. seriata(GenBank:AY259094,AY343353),一种分离株鉴定为B. dothidea(AY236949,AY786319),一种分离株鉴定为黄褐猪笼草(AY259091,AY573217)。 ITS区和EF1-α基因的序列分别从KC178817至KC178824和从KF546829至KF546836保藏在GenBank中。对分离的绿芽cv进行了致病性测试。意大利用于八种葡萄球菌的分离株。通过在7天大的菌落边缘上放置一个定植的琼脂塞(直径5毫米),将其接种在用无菌手术刀制成的新鲜伤口部位上,从而对芽进行接种。每个伤口都覆盖有保湿棉,并用Parafilm密封。使用非定殖的PDA塞接种对照芽。 6周后,接种D. seriata,N。luteum和B. dothidea的枝条观察到木质部和韧皮部的变色和坏死的平均长度分别为38.8、17.6和11.2 mm,并且所有三种真菌均重新接种。从坏死组织中分离出来,符合科赫的假设。对照芽未显示出该疾病的症状,并且没有真菌被重新分离。在突尼斯,据报道仅在松树属物种的核糖双歧杆菌(2)引起的柑橘树上发生了与灰霉病有关的死亡。由D. pinea(4)引起,在Quercus spp上。是由D. corticola(3)引起的,以及在橄榄树(Olea europea)上由D. seriata(1)引起的。据我们所知,这是突尼斯的D. seriata,B。dothidea和N. luteum与葡萄死亡相关的首次报道。参考文献:(1)M. Chattaoui等。植物病。 96:905,2012.(2)H. S. Fawcett。加州Citrogr。 (1931)16:208。(3)B. T. Linaldeddu等。 J.植物病理学。 91:234。 2009.(4)B.T. Linaldeddu等。植物病理学。 Mediterr。 47:258,2008年。

+1
+2
100研值 100研值 ¥99课程
检索文献一次
下载文献一次

去下载>

成功解锁2个技能,为你点赞

《SCI写作十大必备语法》
解决你的SCI语法难题!

技能熟练度+1

视频课《玩转文献检索》
让你成为检索达人!

恭喜完成新手挑战

手机微信扫一扫,添加好友领取

免费领《Endnote文献管理工具+教程》

微信扫码, 免费领取

手机登录

获取验证码
登录