Pardo Juan M, Chittarath Khonesavanh, Vongphachanh Pinkham, Hang Le Thi, Oeurn Samoul, Arinaitwe Warren, Rodriguez Rafael, Sophearith Sok, Malik Al Imran, Cuellar Wilmer J
Cassava Program, International Center for Tropical Agriculture (CIAT), The Americas Hub, Km 17 Recta Cali-Palmira, Cali 763537, Colombia.
Plant Protection Center (PPC), Department of Agriculture, Ministry of Agriculture and Forestry, Vientiane P.O. Box 811, Laos.
Plants (Basel). 2023 Jun 4;12(11):2217. doi: 10.3390/plants12112217.
Cassava witches' broom disease (CWBD) is one of the main diseases of cassava in Southeast Asia (SEA). Affected cassava plants show reduced internodal length and proliferation of leaves (phyllody) in the middle and top part of the plant, which results in reduced root yields of 50% or more. It is thought to be caused by phytoplasma; however, despite its widespread distribution in SEA still little is known about CWBD pathology. The overarching goal of this study was to review and corroborate published information on CWBD biology and epidemiology considering recent field observations. We report the following: (1) CWBD symptoms are conserved and persistent in SEA and are distinct from what has been reported as witches' broom in Argentina and Brazil. (2) In comparison with cassava mosaic disease, another major disease of cassava in SEA, symptoms of CWBD develop later. (3) Phytoplasma detected in CWBD-affected plants belong to different ribosomal groups and there is no association study available indicating phytoplasma as the causing agent of CWBD. These findings are essential clues for designing surveillance and management strategies and for future studies to better understand the biology, tissue localization and spatial spread of CWBD in SEA and other potential risk areas.
木薯扫帚病（CWBD）是东南亚木薯的主要病害之一。受感染的木薯植株节间长度缩短，植株中上部叶片增生（叶变），导致块根产量降低50%或更多。该病被认为是由植原体引起的；然而，尽管它在东南亚广泛分布，但人们对木薯扫帚病的病理学仍知之甚少。本研究的总体目标是结合近期的实地观察结果，回顾并证实已发表的关于木薯扫帚病生物学和流行病学的信息。我们报告如下：（1）木薯扫帚病症状在东南亚具有一致性和持续性，且与阿根廷和巴西报道的扫帚病不同。（2）与东南亚木薯的另一种主要病害木薯花叶病相比，木薯扫帚病的症状出现较晚。（3）在受木薯扫帚病影响的植株中检测到的植原体属于不同的核糖体组，且尚无关联研究表明植原体是木薯扫帚病的致病因子。这些发现是设计监测和管理策略以及未来研究的重要线索，有助于更好地了解木薯扫帚病在东南亚及其他潜在风险地区的生物学特性、组织定位和空间传播。
