Moral J, López-Escudero F J, Roca L F, Blanco-López M A, Trapero A
Departamento de Agronomía, ETSIAM, Universidad de Córdoba. Campus de Rabanales, Edif. C4, 14071-Córdoba, Spain.
Plant Dis. 2010 Mar;94(3):382. doi: 10.1094/PDIS-94-3-0382B.
Pistachio (Pistacia vera L.) trees in the Castilla La Mancha and Andalusia regions of central and southern Spain are grown close to olive orchards, which are often severely affected by Verticillium dahliae. During the last decade, wilt and death of one or several branches have been observed on pistachio (cv. Kerman) scions grafted on rootstock (P. terebinthus). Discoloration of vascular tissue was occasionally observed. In five surveyed orchards, incidence of affected trees was less than 2%. Wood chips with the bark removed from symptomatic trees were washed in running tap water, surface disinfested in 0.5% sodium hypochlorite for 1 min, and placed onto potato dextrose agar plates incubated at 25°C in the dark. Isolates were identified as V. dahliae on the basis of the characteristics of microsclerotia, conidiophores, and conidia. V. dahliae isolate V117 from olive was used as reference (1). The fungus was also isolated from soil in pistachio orchards using wet sieving and a modified sodium polypectate agar medium (1). Inoculum density varied from 0 to 4.73 microsclerotia per gram of soil. P. terebinthus seedlings were inoculated with two isolates of V. dahliae from pistachio trees by injecting the stems with 50 μl of a conidial suspension (10 conidia per ml) (2). Wilt symptoms of varying severity developed in 12 and 15 seedlings of the 20 pistachio seedlings inoculated with each of two isolates. No symptoms developed on the control seedlings. The pathogen was recovered from stem tissues of inoculated plants. To our knowledge, this is the first report of Verticillium wilt of pistachio in Spain. This study demonstrates the susceptibility of certain rootstocks to V. dahliae and the importance of using resistant rootstocks, such as UCBI (2), in pistachio plantations established on soils infested by V. dahliae. References: (1) F. J. López-Escudero and M. A. Blanco-López. Plant Dis. 91:1372, 2007. (2) D. P. Morgan et al. Plant Dis. 76:310, 1992.
西班牙中部和南部的卡斯蒂利亚-拉曼恰及安达卢西亚地区的阿月浑子（黄连木）树种植在靠近橄榄园的地方，而橄榄园常常受到大丽轮枝菌的严重影响。在过去十年间，人们观察到嫁接在砧木（笃耨香）上的阿月浑子（品种克尔曼）接穗出现一根或几根枝条枯萎和死亡的情况。偶尔还观察到维管束组织变色。在五个被调查的果园中，受影响树木的发生率低于2%。将有症状树木上剥去树皮的木片在流动的自来水中冲洗，在0.5%次氯酸钠中进行表面消毒1分钟，然后放在马铃薯葡萄糖琼脂平板上，于25°C黑暗条件下培养。根据微菌核、分生孢子梗和分生孢子的特征，将分离物鉴定为大丽轮枝菌。来自橄榄的大丽轮枝菌分离物V117用作参照（1）。还使用湿筛法和改良的聚果胶酸钠琼脂培养基从阿月浑子果园的土壤中分离出该真菌（1）。每克土壤中的接种体密度从0到4.73个微菌核不等。通过向笃耨香幼苗的茎部注射50微升分生孢子悬浮液（每毫升10个分生孢子），用从阿月浑子树上分离出的两种大丽轮枝菌分离物对笃耨香幼苗进行接种（2）。在接种两种分离物中的每一种的20株阿月浑子幼苗中，分别有12株和15株出现了不同严重程度的枯萎症状。对照幼苗未出现症状。从接种植物的茎组织中重新分离出了病原菌。据我们所知，这是西班牙阿月浑子黄萎病的首次报道。本研究证明了某些砧木对大丽轮枝菌的易感性，以及在种植于受大丽轮枝菌侵染土壤上的阿月浑子种植园中使用抗性砧木（如UCBI）（2）的重要性。参考文献：（1）F. J. López-Escudero和M. A. Blanco-López。植物病害91:1372，2007。（2）D. P. Morgan等人。植物病害76:310，1992。
