茉莉酸甲酯对脆红李采后病原菌的抑制作用

瞿光凡,巴良杰,雷霁卿,马超,张旭阳,曹森*

(贵阳学院食品与制药工程学院,贵州 贵阳 550005)

摘 要:为确定脆红李果实采后主要病原菌的种类及茉莉酸甲酯对其抑制效果,从脆红李贮藏期病果中分离纯化病原菌,通过致病性检测、形态学鉴定和rDNA-ITS序列分析对病原菌进行鉴定;并采用体外实验研究不同浓度的茉莉酸甲酯(0、0.1、0.2、0.3、0.4、0.5 mmol/L)对脆红李采后主要致病菌的抑制效果及室内毒力测定。结果表明,引起脆红李采后腐烂的病原菌主要为灰葡萄孢菌(Botrytis cinerea)和链格孢菌(Alternaria alternata);经体外实验得出,不同浓度的茉莉酸甲酯能抑制两株病原菌菌丝的生长,其中,0.4 mmol/L及0.5 mmol/L的茉莉酸甲酯能够有效抑制脆红李采后病原菌的生长,但其对病原菌的抑制作用无显著差异(P>0.05);在体外培养5 d时,0.4 mmol/L的茉莉酸甲酯对灰葡萄孢菌和链格孢菌的抑制率分别为89.3%、86.3%;在培养2 d时,茉莉酸甲酯对灰葡萄孢菌和链格孢菌的EC50分别为0.154、0.228 mmol/L,而在5 d时为0.193、0.348 mmol/L。由此得出适宜浓度的茉莉酸甲酯能够有效抑制脆红李贮藏期病原菌的生长,后期可将其用于脆红李采后病害的防治及贮藏保鲜的研究。

关键词:脆红李;病原菌;分离鉴定;茉莉酸甲酯;抑菌效果

脆红李(Prunus salicina cv.‘Cuihongli’)属蔷薇科(Rosaceae)李属(Prunus L.)果实[1],广泛种植于川、渝、黔等西南高山地区[2]。脆红李果实成熟采收于高温多雨季节,果实极易受到损伤、果肉变软以及遭受病原菌的侵染,导致果实腐败变质,脆红李贮藏期腐烂是脆红李产业急需解决的问题。目前,国内外已报道的李果病害主要有褐腐病、炭疽病、黑霉病、黑斑病、红点病、袋果病等[3-6]。凡先芳等[3]采用1-甲基环丙烯(1-methylcyclopropene,1-MCP)结合戊唑醇处理青脆李,显著降低青脆李果实在贮藏期间褐腐病的发生。赵宁等[4]对桃形李采后橘青霉进行分离鉴定,发现致病菌为扩展青霉Penicillium expansum,但关于脆红李采后贮藏期致病菌的种类及病害防治的研究较少。

目前,控制采后水果腐败变质的常见技术有化学杀菌剂处理、减压气调以及低温贮藏,而化学杀菌剂的药量残留不易控制,减压气调及低温贮藏不能完全抑制病原菌的生长繁殖[3,7-9]。茉莉酸甲酯(methyl jasmonate,MeJA)是一种植物内源性激素,不仅参与调节采后果蔬的生长、分化、成熟等生理活动,还能诱导增强采后果蔬在贮藏过程中抗冷性及抗病性[10-13]。已有研究表明茉莉酸甲酯能显著提高猕猴桃[14]、蓝莓[15]、番茄[16]等采后农作物的抗病性及保鲜效果。Wang等[15]报道了茉莉酸甲酯通过激活苯丙素途径以及提高果实内防御相关酶来诱导提高蓝莓对灰霉病的抗病性。黎晓茜等[17]研究结果表明茉莉酸甲酯通过破坏猕猴桃软腐病菌的细胞膜通透性、促使细胞壁溶解以及细胞内物质外渗,从而有效地抑制病原菌的生长繁殖。本研究从贮藏期脆红李病果中分离鉴定出两株病原菌,探究不同浓度茉莉酸甲酯对病原菌的体外抑制作用,并进行室内毒力测试,以期为脆红李采后病害防控提供一定的理论依据。

1 材料与方法

1.1 材料与试剂

脆红李:2020年8月采摘于贵阳市修文县谷堡乡实验基地,为八九成熟果实,果实采后常温放置至果面长菌后进行分离鉴定;茉莉酸甲酯(纯度98%,分子量224.30):上海麦克林生化科技有限公司;引物ITS1和 ITS4、DNA Marker C、DNA提取试剂盒、双蒸水(ddH2O):生工生物工程(上海)股份有限公司;马铃薯葡萄糖琼脂培养基(potato dextroseagar,PDA):上海博微生物科技有限公司。

1.2 仪器与设备

ChemiDoc免染型蛋白印迹成像系统:成都百乐科技有限公司;CX21光学显微镜:日本奥林巴斯有限公司;SHP-2500低温生化培养箱:上海精宏实验设备有限公司。

1.3 方法

1.3.1 病原菌的分离与纯化

随机选取脆红李贮藏期腐败的果实,采用组织分离法[18]对病原菌进行分离与纯化。将腐败的果实置于75%酒精中浸泡30 s,无菌水冲洗2次~3次后用无菌纸将果实表面水分吸干,置于超净工作台中。用灭过菌的手术刀切取病健交界处的组织放于PDA培养基上,置于28℃恒温培养箱中进行培养,待果肉组织长出的菌落直径为1 cm~3 cm时,用接种针挑取不同形态的菌落边缘的菌丝于新的培养基上并于28℃恒温培养,经划线分离直至获得单孢菌落,将纯化的菌株于4℃冰箱斜面保存。

1.3.2 病原菌形态学鉴定

将纯化的病原菌接种于新的培养基上,于28℃恒温培养并观察记录各致病菌在PDA培养基上的菌落颜色、特征以及基部变化,并结合各致病菌在光学显微镜下菌丝、分生孢子及孢子梗的形态与结构来初步鉴定病原菌。

1.3.3 病原菌致病性检测

病原菌致病性测定依据科柯赫法则进行。挑选健康、无病虫害、无损伤的脆红李果实,用无菌水冲洗果实表皮,75%酒精擦拭消毒后再用无菌水冲洗2次~3次,置于超净工作台中自然晾干。采用直径为4 mm的无菌打孔器取菌饼损伤接种于脆红李果实,每种致病菌重复3个果,并将损伤接种的果实置于温度25℃、湿度95%的培养箱中培养5 d,记录果实的发病情况,采用十字交叉法测量病斑直径。挑取病斑处的菌丝进行划线分离,获得纯病原菌后与原接种的菌株进行形态鉴定对比,其形态一致后进行下一步试验。

1.3.4 病原菌分子生物学鉴定

用无菌镊子挑取一定量的病原菌菌丝体于无菌研钵中,液氮研磨至粉末状,参照植物基因组DNA提取试剂盒提取病原菌基因组DNA。25 μL反应体系:Taq Master Mix 12.5 μL、引物 ITS1 和 ITS4 1 μL、模板DNA 1 μL、ddH2O 补加至 25 μL。选取真菌通用引物ITS1(5’-TCCGTAGGTGAACCTGCGG-3’)和 ITS4(5’-TCCTCCGCTTATTGATATGC-3’)进行病原菌rDNA-ITS序列扩增,其扩增程序设置:94℃预变性3 min;94℃变性 1 min,55℃退火 30 s,72℃延伸 1 min,30个循环;72℃终延伸10 min。对聚合酶链式反应(polymerase chain reaction,PCR)产物进行测序,测序结果在NCBI网站进行BLAST比对分析,下载同源性较高的菌株序列,采用MEGA 7软件以邻接法构建系统发育树[7],并结合病原菌的形态特征对其进行鉴定。

1.3.5 茉莉酸甲酯对病原菌体外抑制及室内毒力测试

根据菌丝生长速率法测定茉莉酸甲酯对病原菌体外抑制效果,分别称取不同质量的茉莉酸甲酯加入到灭菌的PDA培养基中,充分摇匀。使每个平板PDA培养基中茉莉酸甲酯浓度分别为 0、0.1、0.2、0.3、0.4、0.5 mmol/L,待培养基冷却后备用。用无菌打孔器(直径4 mm)从培养5 d的病原菌菌落上打取菌饼,菌丝面放于培养基中央,每个浓度重复3次。于28℃恒温培养箱中培养5d,每日采用十字交叉法测量菌落直径。以茉莉酸甲酯浓度的对数值为横坐标,抑菌率为纵坐标,计算茉莉酸甲酯对病原菌菌丝毒力方程,并采用Graphpad prism 7软件计算半最大效应浓度(half maximal effective concentration,EC50),抑菌率的计算公式如下。

1.4 数据分析

试验基础数据采用Excel 2016软件进行统计分析,采用SPSS19.0软件的Duncan法对数据进行差异显著性分析(P<0.05表示差异显著),采用Origin 2018对数据进行作图。

2 结果与分析

2.1 病原菌形态学鉴定

经组织分离、划线分离及单孢培养,根据形态特征与培养特性获得两种菌株,记作CHL-1和CHL-2,脆红李病原菌形态特征见图1。

图1 脆红李病原菌形态特征
Fig.1 Morphological characteristics of pathogens of Prunus salicina

a、b、c分别为CHL-1正面菌落形态、背部菌落形态、分生孢子;d、e、f分别为CHL-2正面菌落形态、基部菌落形态、分生孢子。

第一种(图1a)菌丝初期为白色绒毛状,后期逐渐变成灰色且菌丝端有微小的颗粒,基部初期由暗黄色逐步转化为灰色或暗灰色(图1b),培养7 d后产生分生孢子,光学显微镜下菌丝呈淡黄色,分生孢子呈椭圆形或卵泡形、透明无隔膜(图1c)。其形态特征及培养特性与He等[19]研究的灰葡萄孢菌(Botrytis cinerea)一致,初步鉴定为灰葡萄孢属(Botrytis sp)。

第二种(图1d)菌丝初期紧密、呈米黄色,后期逐渐变为灰绿色;基部外层暗红色,内层黑色或褐色且有褶皱裂痕(图1e),培养5 d后产生不成熟的分生孢子,显微镜下菌丝透明且有分隔,孢子呈卵圆形或棒状,有明显的纵横分隔(图1f)。其形态特征与王丹等[7]研究的链格孢菌(Alternaria alternata)的形态一致,初步鉴定为链格孢属(Alternaria sp)。

2.2 病原菌致病性检测

从脆红李果实发病组织中分离纯化出2株病原菌,采用刺伤接种法将2株病原真菌回接至健康的果实上,置于25℃、95%湿度的培养箱中培养5 d,观察发病情况,结果见图2、图3。

图2 病原菌回接脆红李果实5 d发病症状
Fig.2 Disease symptom of Prunus salicina after inoculation with pathogens for 5 days

a、b为CK组(接无菌菌饼);c、d为接种CHL-1菌株发病状态;e、f为接种CHL-2菌株发病状态。

图3 病原菌回接脆红李果实5 d时病斑直径
Fig.3 Diameter of diseased spot of Prunus salicina after inoculation with pathogens for 5 days

不同小写字母表示具有显著性差异(P<0.05)。

菌株CHL-1刺伤接种5 d后,刺伤部位周围长出大量肉眼可见白色绒毛状菌丝(图2c),果肉组织松弛变软、褐变逐渐扩展至果心(图2d);菌株CHL-2刺伤接种5 d后,损伤部位长出灰绿色菌丝(图2e),果肉组织较为紧密,刺伤部位周围果肉褐变较浅(图2f),而对照组均无发病症状(图2a),果肉组织紧密、无褐变病症(图2b)。取回接果实发病部位再次进行分离培养,得到的菌株形态特征及培养特性与原菌株(CHL-1、CHL-2)一致。

由图3可知,两种病原菌刺伤接种5 d后,菌株CHL-1与CHL-2的病斑直径分别为18.43、10.60 mm,并且菌株CHL-1的病斑直径显著大于菌株CHL-2(P<0.05),结合图1可知,菌株CHL-1对果实的致病性强于菌株CHL-2。

2.3 病原菌分子生物学鉴定

提取两种病原菌DNA进行PCR扩增,扩增产物经琼脂糖凝胶电泳成像,结果见图4。系统发育树结果见图5。

图4 两株病原菌rDNA-ITS序列琼脂糖凝胶电泳成像图
Fig.4 rDNA-ITS agarose gel electrophoresis of two strains of pathogens

M为DNA marker C;1为CHL-1菌株PCR产物;2为CHL-2菌株PCR产物。

图5 基于rDNA-ITS序列病原菌系统发育树
Fig.5 Phylogenetic tree of pathogens based on rDNA-ITS sequence

由图4可知,菌株CHL-1与CHL-2的rDNA-ITS序列长度为500 bp~700 bp。由图5可知,菌株CHL-1的rDNA-ITS序列与Botrytis cinerea NR151843处于同一分支且相似度高达100%,结合其形态学鉴定,确定菌株CHL-1为灰葡萄孢菌(Botrytis cinerea)。菌株CHL-2的rDNA-ITS序列与Alternaria alternata NR163686具有较高的同源性且处于同一分支,结合形态学鉴定,确定菌株CHL-2为链格孢菌(Alternaria alternata)。

2.4 茉莉酸甲酯对脆红李采后病原菌的抑制作用

2.4.1 茉莉酸甲酯对病原菌体外抑制效果

茉莉酸钾酯对脆红李病原菌体外抑制效果见图6。

由图6可知,在含不同浓度茉莉酸甲酯的培养基中,灰葡萄孢菌和链格孢菌的菌落直径均随着培养时间的延长呈上升的趋势。在培养2 d时,不同浓度的茉莉酸甲酯处理均显著抑制灰葡萄孢菌和链格孢菌菌丝生长(P<0.05),其中0.4、0.5 mmol/L茉莉酸甲酯完全抑制两株菌的生长。在培养5d时,0.1、0.2、0.3、0.4、0.5 mmol/L处理组对灰葡萄孢菌抑制率分别为31.4%、47.0%、88.4%、89.3%、96.9%,其中 0.3、0.4、0.5 mmol/L处理组与其他处理组均有显著性差异(P<0.05);而对链格孢菌抑制率为8.1%、37.1%、56.0%、86.3%、94.6%,其中0.4、0.5 mmol/L处理组与其他处理组均有显著性差异(P<0.05)。综上可知,适宜浓度的茉莉酸甲酯能有效抑制脆红李采后病原菌的生长。

图6 茉莉酸钾酯对脆红李病原菌体外抑制效果
Fig.6 In vitro inhibitory effect of methyl jasmonate on the pathogens of Prunus salicina

A为灰葡萄孢菌;B为链格孢菌,不同小写字母代表组间具有显著性差异(P<0.05)。

2.4.2 茉莉酸甲酯对病原菌的室内毒力测试

基于茉莉酸甲酯体外抑制效果试验,分别对灰葡萄孢菌、链格孢菌在2 d和5 d时菌丝的生长情况及数据进行统计分析,分别求出毒力方程和EC50

由表1可知,在2 d时,茉莉酸甲酯对灰葡萄孢菌和链格孢菌的EC50分别为0.154、0.193 mmol/L,而培养5 d时,EC50分别为0.228、0.348 mmol/L。由此可见,茉莉酸甲酯对灰葡萄孢菌的抑菌效果优于链格孢菌。

表1 茉莉酸甲酯对灰葡萄孢菌、链格孢菌的室内毒力
Table 1 Indoor toxicity of methyl jasmonate to Botrytis cinerea and Alternaria alternata

菌株培养间/d毒力方程相关系数EC50/(mmol/L)灰葡萄孢菌 2 y=1.058 4x+1.588 9 0.841 2 0.154 5 y=1.019 2x+1.301 5 0.915 7 0.228链格孢菌 2 y=1.668 3x+1.949 0 0.959 6 0.193 5 y=1.268 1x+1.304 9 0.969 5 0.348

3 讨论

灰葡萄孢菌的有性态为富克尔葡萄孢盘菌(Botryotinia fuckeliana),其属包括23种,常见具有致病性的有中华葡萄生葡萄孢(Botryotinia sinoviticola)、草莓葡萄孢(Botryotinia frgariae)和卡罗莱纳葡萄孢(Botryotinia caroliniana)[20-21]。链格孢属真菌主要依据分生孢子的形状、大小、纵横分隔状况以及分生孢子梗形态特征进行种级形态分类,常见的链格孢菌有草莓链格孢、日本梨链格孢、苹果链格孢和烟草链格孢等[22]。灰葡萄孢菌(Botrytis cinerea)和链格孢菌(Alternaria alternata)在采后农作物上的致病能力强[23],可以侵染导致葡萄[24]、番茄[16]、西兰花[25]、桔柚[26]等多类经济农作物快速腐败。本研究发现,引起脆红李采后腐败的主要病原菌为灰葡萄孢菌(Botrytis cinerea)和链格孢菌(Alternaria alternata)。

病原菌浸染是导致果蔬采后品质劣变的主要因素之一。大量研究表明,化学药物可有效杀死病原菌。但化学药物广泛应用导致病原菌耐药性且严重影响食品安全。因而也有很多学者不断开发天然、高效、安全的贮藏技术,从而有效延长果实的贮藏期,提高果实采后品质。茉莉酸甲酯属于一种植物激素,据报道,其已广泛应用于果蔬采后保鲜,有效维持果蔬采后品质、延缓果蔬营养物质的损失,并能提高果实采后抗病性[27]。研究发现,茉莉酸甲酯能有效抑制葡萄座腔菌(Botryosphaeria dothidea)菌丝生长,破坏菌丝细胞膜完整性导致病原菌失活[17]。此外,于萌萌等[28]研究表明,茉莉酸甲酯不仅有效抑制番茄灰葡萄孢菌(Botrytis cinerea)的生长,还促进果实抗病相关蛋白、酚类物质及番茄红素的积累,增强番茄果实的抗病性。本研究体外试验结果表明,茉莉酸甲酯有效抑制灰葡萄孢菌(Botrytis cinerea)和链格孢菌(Alternaria alternata)的菌丝生长,室内毒力测试发现茉莉酸甲酯在第2天、第5天时,对灰葡萄孢菌和链格孢菌的EC50分别为0.154、0.193 mmol/L 和 0.228、0.348 mmol/L,此结果表明茉莉酸甲酯对灰葡萄孢菌(Botrytis cinerea)的抑菌效应强于链格孢菌(Alternaria alternata)。但关于茉莉酸甲酯的抑菌机制及其对脆红李的贮藏保鲜效果还需进一步深入研究。

4 结论

本研究发现引起脆红李腐败的病原菌主要为灰葡萄孢菌(Botrytis cinerea)和链格孢菌(Alternaria alternata),并通过体外试验发现茉莉酸甲酯在一定程度上能有效抑制两株病原菌的生长。因此,茉莉酸甲酯处理可作为脆红李采后病害防控的一种有效策略。

参考文献:

[1] 张炜,吴正云,罗力,等.复合处理方式延长脆红李常温货架期的研究[J].食品研究与开发,2019,40(7):110-114.ZHANG Wei,WU Zhengyun,LUO Li,et al.Effects of comprehensive treatments on shelf life quality of Prunus salicina cv.'cuihongli'stored at room temperature[J].Food Research and Development,2019,40(7):110-114.

[2] 李兴武,章黎黎.热空气结合乙醇熏蒸保鲜脆红李的工艺优化[J].保鲜与加工,2019,19(6):34-39.LI Xingwu,ZHANG Lili.Optimization of hot air combined with ethanol fumigation on preservation of Prunus salicina cv.'cuihongli'[J].Storage and Process,2019,19(6):34-39.

[3] 凡先芳,张婕,姚世响,等.1-MCP和戊唑醇处理对青脆李果实贮藏期病害和品质的影响[J].食品科学,2016,37(24):292-298.FAN Xianfang,ZHANG Jie,YAO Shixiang,et al.Effects of 1-MCP and tebuconazole treatments on disease and quality of'qingcui'plum fruits during storage[J].Food Science,2016,37(24):292-298.

[4] 赵宁,宋昱辉,陈莉,等.嵊州桃形李采后橘青霉分离鉴定及室内抑菌试验[J].福建农业学报,2018,33(4):407-412.ZHAO Ning,SONG Yuhui,CHEN Li,et al.Isolation,identification and antibacterial tests on Penicillium citrinum for postharvest Shengzhou plums[J].Fujian Journal of Agricultural Sciences,2018,33(4):407-412.

[5] 伍文宪,刘佳,张蕾,等.脆红李“火烧叶”病原鉴定[J].西南农业学报,2018,31(2):342-346.WU Wenxian,LIU Jia,ZHANG Lei,et al.Identification of pathogenic fungus causing'flaming leaves'on plum(Prunus salicina lindl.c.v.cuihongli)[J].Southwest China Journal of Agricultural Sciences,2018,31(2):342-346.

[6]JANISIEWICZ W J,JURICK W M II,VICO I,et al.Culturable bacteria from plum fruit surfaces and their potential for controlling brown rot after harvest[J].Postharvest Biology and Technology,2013,76:145-151.

[7] 王丹,张静,贾晓曼,等.蓝莓采后主要病原菌的分离鉴定及肉桂精油抑菌效果[J].食品科学,2019,40(24):167-172.WANG Dan,ZHANG Jing,JIA Xiaoman,et al.Identification of dominant postharvest pathogens of blueberry fruit and antifungal activity of cinnamon oil against them[J].Food Science,2019,40(24):167-172.

[8] 王雷,李华,张华,等.β-氨基丁酸抑制草莓低温贮藏过程中灰霉病的效果及其机理[J].食品科学,2017,38(21):272-278.WANG Lei,LI Hua,ZHANG Hua,et al.Inhibitory effect and mechanisms of β-aminobutyric acid on grey mold(Botrytis cinerea)in strawberry fruits during low temperature storage[J].Food Science,2017,38(21):272-278.

[9] WANG J,PAN H X,WANG R,et al.Patterns of flesh reddening,translucency,ethylene production and storability of'Friar'plum fruit harvested at three maturity stages as affected by the storage temperature[J].Postharvest Biology and Technology,2016,121:9-18.

[10]郑俊峰,谢建华,庞杰.外源茉莉酸甲酯对解放钟枇杷果实采后品质的影响[J].食品与机械,2020,36(10):120-124.ZHENG Junfeng,XIE Jianhua,PANG Jie.The effect of exogenous MeJA on postharvest quality of Jiefang Zhong loquat fruit[J].Food&Machinery,2020,36(10):120-124.

[11]VENKATACHALAM K,THONGBOUR P,NAGARAJAN M.Effect of methyl jasmonate fumigation and packaging on chilling injury and physiochemical quality changes of stored green bell peppers[J].Carpathian Journal of Food Science and Technology,2018,10(2):120-132.

[12]MIN D D,LI F J,ZHANG X H,et al.SlMYC2involved in methyl jasmonate-induced tomato fruit chilling tolerance[J].Journal of Agricultural and Food Chemistry,2018,66(12):3110-3117.

[13]LI J Z,MIN D D,LI Z L,et al.Regulation of sugar metabolism by methyl jasmonate to improve the postharvest quality of tomato fruit[J].Journal of Plant Growth Regulation,2022,41(4):1615-1626.

[14]DA SILVA M N,VASCONCELOS M W,PINTO V,et al.Role of methyl jasmonate and salicylic acid in kiwifruit plants further subjected to Psa infection:Biochemical and genetic responses[J].Plant Physiology and Biochemistry,2021,162:258-266.

[15]WANG H B,KOU X H,WU C E,et al.Methyl jasmonate induces the resistance of postharvest blueberry to gray mold caused by Botrytis cinerea[J].Journal of the Science of Food and Agriculture,2020,100(11):4272-4281

[16]MIN D D,LI F J,CUI X X,et al.SlMYC2are required for methyl jasmonate-induced tomato fruit resistance to Botrytis cinerea[J].Food Chemistry,2020,310:125901.

[17]黎晓茜,龙友华,尹显慧,等.茉莉酸甲酯处理对猕猴桃软腐病菌作用机制及果实品质的影响[J].食品科学,2019,40(15):239-248.LI Xiaoqian,LONG Youhua,YIN Xianhui,et al.Mechanism of action of methyl jasmonate against kiwifruit soft rot and its effect on fruit quality[J].Food Science,2019,40(15):239-248.

[18]LI L,PAN H,CHEN M Y,et al.Isolation and identification of pathogenic fungi causing postharvest fruit rot of kiwifruit(Actinidia chinensis)in China[J].Journal of Phytopathology,2017,165(11-12):782-790.

[19]HE C,ZHANG Z Q,LI B Q,et al.Effect of natamycin on Botrytis cinerea and Penicillium expansum—Postharvest pathogens of grape berries and jujube fruit[J].Postharvest Biology and Technology,2019,151:134-141.

[20]高智谋,李艳梅,李喜玲,等.源自不同寄主的灰葡萄孢生物学特性的比较研究[J].菌物学报,2009,28(3):370-377.GAO Zhimou,LI Yanmei,LI Xiling,et al.Comparison of the biological characteristics of Botrytis cinerea isolates from different hosts[J].Mycosystema,2009,28(3):370-377.

[21]DE MOURA G G D,DE BARROS A V,MACHADO F,et al.Endophytic bacteria from strawberry plants control gray mold in fruits via production of antifungal compounds against Botrytis cinerea L[J].Microbiological Research,2021,251:126793.

[22]HUANG F,FU Y S,NIE D N,et al.Identification of a novel phylogenetic lineage of Alternaria alternata causing Citrus brown spot in China[J].Fungal Biology,2015,119(5):320-330.

[23]杨小林,张佑宏,王佐乾,等.鄂北岗地山药病害病原菌鉴定[J].福建农业学报,2021,36(1):59-64.YANG Xiaolin,ZHANG Youhong,WANG Zuoqian,et al.Pathogens infecting Chinese yams planted on ridges in northern Hubei[J].Fujian Journal of Agricultural Sciences,2021,36(1):59-64.

[24]XU D D,DENG Y Z,HAN T Y,et al.In vitro and in vivo effectiveness of phenolic compounds for the control of postharvest gray mold of table grapes[J].Postharvest Biology and Technology,2018,139:106-114.

[25]WANG B R,LOU T C,WEI L L,et al.Biochemical and molecular characterization of Alternaria alternata isolates highly resistant to procymidone from broccoli and cabbage[J].Phytopathology Research,2021,3(1):15.

[26]葛慈斌,黄素芳,阮传清,等.建阳桔柚两种真菌病原菌的鉴定[J].福建农业学报,2019,34(8):958-964.GE Cibin,HUANG Sufang,RUAN Chuanqing,et al.Pathogens of diseases on Jianyang tangelos[J].Fujian Journal of Agricultural Sciences,2019,34(8):958-964.

[27]赵曼如,胡文忠,于皎雪,等.茉莉酸甲酯对果蔬抗性、抗氧化活性及品质影响的研究进展[J].食品工业科技,2020,41(4):328-332.ZHAO Mabru,HU Wenzhong,YU Jiaoxue,et al.Research progress on effects of methyl jasmonate on resistance,antioxidant activity and quality of fruits and vegetables[J].Science and Technology of Food Industry,2020,41(4):328-332.

[28]于萌萌,申琳,生吉萍.茉莉酸甲酯诱导采后番茄果实抗病的作用[J].食品科学,2012,33(9):11-15.YU Mengmeng,SHEN Lin,SHENG Jiping.Meja-induced disease resistance in postharvest tomato fruits[J].Food Science,2012,33(9):11-15.

Inhibitory Effect of Methyl Jasmonate on Postharvest Storage Disease of Prunus salicina

QU Guang-fan,BA Liang-jie,LEI Qi-qing,MA Chao,ZHANG Xu-yang,CAO Sen*
(Food and Pharmaceutical Engineering Institute,Guiyang University,Guiyang 550005,Guizhou,China)

Abstract:To determine the main pathogens of Prunus salicina after harvest and explore the inhibitory effect of methyl jasmonate on its postharvest storage disease,the pathogens were isolated and purified from the diseased fruit of P.salicina during storage.The pathogens were identified by pathogenicity detection,morphological identification,and rDNA-ITS sequence analysis.In vitro experiments were carried out to study the inhibitory effect of different concentrations of methyl jasmonate (0,0.1,0.2,0.3,0.4 mmol/L,and 0.5 mmol/L)on the main pathogens of P.salicina and measure the indoor virulence.The results showed that the main pathogens causing postharvest decay of P.salicina were Botrytis cinerea and Alternaria alternate.In vitro experiments showed that different concentrations of methyl jasmonate inhibited the mycelial growth of the two strains of pathogens,among which 0.4 mmol/L and 0.5 mmol/L methyl jasmonate effectively inhibited the growth of pathogens of P.salicina after harvest,but there had no significant difference in their inhibitory effects on the pathogens(P>0.05).The inhibition rates of 0.4 mmol/L methyl jasmonate on Botrytis cinerea and Alternaria alternata were 89.3%and 86.3%,respectively,on the 5thday of in vitro cultivation.The EC50of methyl jasmonate on Botrytis cinerea and Alternaria alternata were 0.154 mmol/L and 0.228 mmol/L,respectively,on the 2nd day of in vitro cultivation,and were 0.193 mmol/L and 0.348 mmol/L on the 5th day of in vitro cultivation.It is concluded that the appropriate concentration of methyl jasmonate can effectively inhibit the growth of pathogens in P.salicina during storage,which can be used in the postharvest disease control and the storage and preservation of P.salicina in the later stage.

Key words:Prunus salicina;pathogens;isolation and identification;methyl jasmonate;bacteriostatic effect

DOI:10.12161/j.issn.1005-6521.2022.24.014

基金项目:贵阳市科技计划项目(筑科合同[2020]37-1号);贵阳学院科研资金资助项目(GYU-KY-[2022])

作者简介:瞿光凡(1997—),男(汉),硕士研究生,研究方向:农产品贮藏与加工。

*通信作者:曹森(1988—),男,教授,硕士,研究方向:农产品贮藏与加工。

引文格式:

瞿光凡,巴良杰,雷霁卿,等.茉莉酸甲酯对脆红李采后病原菌的抑制作用[J].食品研究与开发,2022,43(24):95-101.

QU Guangfan,BA Liangjie,LEI Qiqing,et al.Inhibitory Effect of Methyl Jasmonate on Postharvest Storage Disease of Prunus salicina[J].Food Research and Development,2022,43(24):95-101.

加工编辑:张立娟

收稿日期:2021-12-29