Page 159 - 《广西植物》2023年第7期
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7 期                   刘海燕等: 蓖麻根腐病抗性鉴定及其 SSR 标记的初步建立                                       1 3 2 7

                 evaluate the resistant level of accessions objectively. (2) According to the criteriaꎬ the resistance of 252 accessions were
                 divided into five grades from high to lowꎬ among which Grade 1 was high resistance and Grade 2 was moderate
                 resistance. The number of accessions with different grades from 1 to 5 were 105ꎬ 25ꎬ 33ꎬ 31 and 58ꎬ respectivelyꎬ
                 accounting for 42%ꎬ 10%ꎬ 13%ꎬ 12% and 23%ꎬ respectively. A total of 130 resistant accessions were identifiedꎬ of
                 which 105 were high resistance and 25 were moderate resistance. (3) The proportion of resistant accessions in wild
                 accessions (66%) was much higher than that in cultivated accessions (35%). Among wild accessions from South Chinaꎬ
                 69% were resistant accessionsꎬ and 60% were high resistance accessions. It is strongly suggested that the research and
                 utilization of wild accessionsꎬ especially the wild accessions in South Chinaꎬ should be an important direction of
                 resistance breeding in the future. ( 4 ) Eight SSR markers associated with the resistance were preliminarily
                 established. Although different resistant accessions carried different markers or marker combinationsꎬ most of them
                 carried three to four of the above markersꎬ thereforeꎬ they can be used as resistant molecular markers for assisted
                 selection. The results of this study provide an effective method and evaluation criteria for root rot resistance
                 identificationꎬ screen out a number of resistance genetic resources urgently needed in breedingꎬ and preliminarily
                 establish the SSR markers available for assisted selectionꎬ which lay an important foundation for resistance breeding of
                 castor bean root rot.
                 Key words: castor beanꎬ root rotꎬ resistance identificationꎬ Fusarium solaniꎬ conidia suspensionꎬ SSR



                蓖麻(Ricinus communis) 属于大戟科蓖麻属植                 据发病率(Kumar et al.ꎬ 2015)、死亡天数( Shaw et
            物ꎬ一年生草本或多年生草质木本ꎬ是重要的工业                             al.ꎬ 2016) 和枯萎天数( Shaw et al.ꎬ 2018ꎬ 2022)
            用油作物ꎮ 蓖麻的主要经济价值在于蓖麻油ꎮ 由                            进行抗性评价ꎮ
            于独特的理化性质ꎬ蓖麻油广泛应用于航空航天、                                 随着蓖麻在华南地区种植面积的增加ꎬ发病
            机械制造、医药化工、纺织印染等领域( Fan et al.ꎬ                     程度也日趋严重ꎬ平均发病率为 26%ꎬ严重的地块
            2019ꎻ Xu et al.ꎬ 2021)ꎮ 随着经济的发展ꎬ国内外                超过 50%ꎬ甚至全田死亡ꎮ 经采样分离和基因组
            对蓖麻油的需求持续增加ꎬ市场供不应求ꎮ 然而ꎬ                            测序鉴定证明ꎬ最主要的病害是根腐病ꎬ病原菌为
            由于缺乏高产抗病品种ꎬ近十几年来ꎬ我国蓖麻种                             茄腐镰孢菌(Fusarium solani)(Zhou et al.ꎬ 2019)ꎮ
            植面积 持 续 减 少ꎬ 蓖 麻 籽 进 口 依 赖 率 持 续 高 达               除病原菌不同之外ꎬ根腐病发病症状与枯萎病完
            90%以上ꎮ                                             全相同ꎬ均表现为根部维管组织变黑、叶片萎蔫、
                 蓖麻病害种类繁多ꎬ中国报道的有 30 多种                         最后整株枯萎、根系腐烂而死亡ꎮ 目前尚无根腐
            (汤健蓉等ꎬ2021)ꎬ国外报道的有 50 多种( Parmar                   病抗性鉴定方法、评价标准和抗性种质资源筛选
            et al.ꎬ 2018)ꎬ其中枯萎病是最主要的病害ꎬ其病                      方面的研究报道ꎮ
            原菌为尖孢镰刀菌蓖麻专化型(Shaw et al.ꎬ 2018ꎬ                       蓖麻是一个遗传多样性很低的物种( Allan et
            2022)ꎮ 目前枯萎病还没有统一的鉴定方法和评                           al.ꎬ 2008ꎻ Bajay et al.ꎬ 2009 )ꎮ 近 年 来ꎬ Xu 等
            价标准ꎮ 国外常用的接种方法有浸根法( Dange &                        (2019ꎬ 2021) 将目光投向了野生材料ꎬ证明野生
            Desaiꎬ 2003ꎻ Raoof et al.ꎬ 2008)、病盆法( Shaw et      材料的遗传多样性高于栽培材料ꎬ而中国华南野
            al.ꎬ 2016ꎬ 2022 )、 灌 根 法 ( Raoof et al.ꎬ 2008ꎻ     生材料的遗传多样性又高于已报道的其他蓖麻群
            Shaw et al.ꎬ 2016) 和浸种法( Shaw et al.ꎬ 2016)ꎮ       体(汪亚菲等ꎬ2019ꎻAgyenim ̄Boateng et al.ꎬ 2019ꎻ
            浸根法和病盆法工作量大且繁琐ꎬ不适合大批量                              杨婷等ꎬ2020)ꎮ 其中ꎬ中国广东的材料遗传多样
            鉴定ꎻ浸种法虽然操作简单ꎬ但接种感染率低ꎬ其                             性最高ꎬ其次是中国广西ꎬ中国海南的最低( 汪亚
            可靠性还有待验证( Shaw et al.ꎬ 2016)ꎻ灌根法操                  菲等ꎬ2019ꎻAgyenim ̄Boateng et al.ꎬ 2019)ꎮ 这意
            作简单ꎬ只要选择适宜的菌液浓度ꎬ即可模拟大田                             味着野生蓖麻材料ꎬ尤其是中国华南野生蓖麻材
            发病条件ꎬ对材料作出客观评价ꎮ 国内根据茎叶                             料中可能蕴藏着更多的抗性材料ꎮ
            病斑大小及数量将枯萎病抗性划分为 0 ~ 4 共 5 个                           本研究以 252 份蓖麻材料为对象ꎬ通过对其
            等级(沙洪林等ꎬ2002ꎻ刘伟等ꎬ2012)ꎻ国外主要根                       进行表型和分子标记鉴定ꎬ拟探讨以下问题:(1)
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