文婷 李凌云 李娜 郭正紅 王全喜
摘? 要: 通過組織分離純化和分子生物學鑒定,明確了引起草莓葉部新病的致病菌為擬盤多毛孢。以噴灑清水為空白對照,利用不同質量濃度的臭氧水直接噴灑致病菌和生長期的草莓植株,研究臭氧水對致病菌和草莓植株的濃度效應,結果顯示:低濃度臭氧水(0.5~0.8 mg?L-1)對草莓植株的生理生態(tài)變化和致病菌的生長影響較小;中濃度臭氧水(2.2~2.5 mg?L-1)可以顯著抑制致病菌的生長,并促進草莓植株的生長;高濃度臭氧水(4.0~4.3 mg?L-1)可以很好地抑制致病菌的生長,但對草莓葉片有較嚴重的腐蝕作用。因此,中濃度(2.2~2.5 mg?L-1)是噴灑草莓的最適臭氧水濃度。
關鍵詞: 草莓(Fragaria ananassa); 擬盤多毛孢; 分子鑒定; 臭氧水; 濃度效應
中圖分類號: S 154.36? ? 文獻標志碼: A? ? 文章編號: 1000-5137(2020)06-0663-08
Abstract: Through the tissue separation,purification and molecular biological identification technologies,it was confirmed that the pathogenic fungus which caused a new disease of strawberry leaves is Pestalotiopsis.Using pure water as a blank control,ozone waters of different concentrations were sprayed to pathogenic fungus directly and to strawberry leaf surface in its growing period.The concentration effects of ozone water on pathogenic fungus and strawberry leaves were studied respectively.The results showed that:lower concentration ozone water(0.5-0.8 mg?L-1) has little effect on the physiological and ecological changes of strawberry plants and on the growth of pathogenic fungus;medium concentration ozone water(2.2-2.5 mg?L-1) can significantly inhibit the growth of pathogenic fungus and promote the growth of strawberry;higher concentration ozone water(4.0-4.3 mg?L-1) can well inhibit the growth of pathogenic fungus.However,it has a serious corrosion effect on strawberry leaves.Therefore,the medium concentration(2.2-2.5 mg?L-1) is the most suitable ozone water concentration for spraying on strawberry,which can be used in practical production to effectively prevent and control strawberry fungal diseases.
Key words: strawberry(Fragaria ananassa); Pestalotiopsis; molecular identification; ozone water; concentration effect
0? 引? 言
草莓(Fragaria ananassa)是薔薇科草莓屬的多年生草本植物[1]。作為可食用水果,其味甘酸、性涼、無毒,熱量極低,能潤肺、健脾、補血;富含纖維素、維生素及果膠物質,能預防冠心病及腦溢血;特別是草莓含有的鞣花酸,能有效避免致癌物將健康的細胞轉變?yōu)榘┘毎?,從而預防結腸癌和直腸癌的發(fā)生[2]。因此,草莓作為一種經(jīng)濟價值較高的漿果,深受廣大消費者的青睞。
近幾年,我國草莓種植面積不斷擴大,草莓栽培已遍及全國各地,年平均產(chǎn)量高于世界平均水平。我國的草莓種植主要以溫室或大棚栽培為主,露地栽培相對較少。采用溫室或大棚栽培草莓雖然有很多優(yōu)點,但其具有的高濕、連作等特點,也為病蟲害的發(fā)生創(chuàng)造了極有利的環(huán)境條件。其中病害問題是影響草莓產(chǎn)量的最主要限制因素,多種病害的發(fā)生對草莓生產(chǎn)造成了極大的破壞與影響[3]。目前,國內已經(jīng)報道的溫室或大棚栽培草莓的病害主要有葉斑病、白粉病、灰霉病和根腐病等[4]。
防蟲網(wǎng)可以抵御蟲害的入侵,卻不能有效地防治病害,目前人們主要依靠噴灑化學農藥的方法來控制草莓病害。然而農藥中存在的有機磷類和氨基甲酸酯類等化學成分,極容易殘留在草莓上危害人體健康,并造成環(huán)境污染等問題[5]。因此,尋求農藥的替代品以降低農藥的使用量已經(jīng)迫在眉睫。
臭氧作為一種強氧化劑,可以有效地殺滅細菌芽孢、病原體、真菌及病毒,可溶于水,易分解為氧氣,比較環(huán)保,且成本較低,可應用于醫(yī)學、農業(yè)、餐飲業(yè)等[6]。1997年,美國食品藥品管理局(FDA)認同臭氧完全符合美國FDA評價食品添加劑安全性指標(GRAS)標準,并正式批準臭氧作為一種消毒劑廣泛應用于食品加工生產(chǎn)領域中[7]。國內對臭氧的應用相對較少,目前在蔬菜防治方面已有相關研究,但水果方面的研究相對缺乏。
2.2 致病菌的分子鑒定分析
分離純化出的病原菌由華大基因科技有限公司進行測序,根據(jù)BLAST結果和系統(tǒng)發(fā)育分析,所提取的病原菌樣品與擬盤多毛孢(Pestalotiopsis)親緣關系最近,同源性達100%(圖2~4)。
擬盤多毛孢屬是黑盤孢科(Amphisphaeriaceae)中的無性形真菌類群[19]。2016年趙景楠等[20]首次發(fā)現(xiàn)并報道棒孢擬盤多毛孢(Pestalotiopsis clavispora)能引起草莓葉部新病,危害草莓葉片,進而影響植株的正常生長。該病發(fā)病初期葉上產(chǎn)生褐色斑點,病斑周圍褪綠,具有黃色暈圈;發(fā)病后期整個葉片呈黃褐色干枯死亡。
2.3 臭氧水對草莓致病菌的生長濃度效應
為了探究臭氧水對擬盤多毛孢的作用效果,本研究采用牛津杯十字交叉抑菌法分別用不同質量濃度的臭氧水與該菌作用。從左到右依次往每個培養(yǎng)皿的牛津杯中注入了200 μL的無菌水,以及低濃度、中濃度和高濃度的臭氧水,每種濃度進行3次生物學重復,正置培養(yǎng)3 d后觀察,致病菌生長情況如圖5所示。低濃度臭氧水(0.5~0.8 mg?L-1)對致病菌的作用不明顯,真菌在培養(yǎng)基上的長勢與無菌水對照無明顯差異,該濃度的臭氧水不能抑制致病菌生長,可能是病害的影響導致臭氧水沒有發(fā)揮作用。中濃度臭氧水(2.2~2.5 mg?L-1)和高濃度臭氧水(4.0~4.3 mg?L-1)與致病菌作用后,致病菌的生長明顯得到抑制,且臭氧水濃度越高,抑制效果越明顯??赡苁浅粞跛膹娧趸允蛊淇梢源┩钢虏【毎冢茐闹虏【牡鞍踪|、多糖和氨基酸等物質,從而導致致病菌無法正常生長[21]。
2.4 臭氧水對草莓植株的生長濃度效應
在染菌草莓植株葉片表面噴灑不同質量濃度的臭氧水,連續(xù)噴灑3 d后檢測其生長情況,如圖6所示。噴灑無菌水后的對照組草莓植株呈現(xiàn)青枯狀,從下部葉開始,逐漸向上凋萎、枯死,為典型的擬盤多毛孢葉斑病癥狀[22],如圖6(a),6(e)所示。與對照組相比,低濃度臭氧水作用后,草莓植株上的病菌擴散范圍較大,對致病菌感染的抑制效果不顯著,如圖6(b),6(f)所示。中濃度臭氧水作用后,草莓植株基本未出現(xiàn)致病菌毒害現(xiàn)象,植株生長狀態(tài)良好,含水量、鮮重、株高等各項指標都呈上升趨勢,如圖6(c),6(g)所示。高濃度臭氧水作用后,草莓植株受到腐蝕,地上葉部分變黃或萎蔫,如圖6(d),6(h)所示,表明臭氧水濃度過高會影響草莓植株的正常生長。因此,中濃度(2.2~2.5 mg?L-1)的臭氧水既能抑制致病菌,又能促進草莓生長,最適合用于噴灑草莓植株。
3? 結? 論
經(jīng)過分離純化和分子鑒定分析,得到引起大棚草莓葉部新病的致病菌為擬盤多毛孢(Pestalotiopsis neglecta)。以噴灑無菌水為空白對照,將低濃度(0.5~0.8 mg?L-1)、中濃度(2.2~2.5 mg?L-1)和高濃度(4.0~4.3 mg?L-1)3個質量濃度的臭氧水分別作用于草莓致病菌——擬盤多毛孢和生長期的草莓植株上,研究結果表明:低濃度的臭氧水對致病菌的生長基本無抑制作用,中濃度的臭氧水對致病菌的生長有顯著的抑制作用。但臭氧水質量濃度超過4.0 mg?L-1時,對草莓植株有較嚴重的腐蝕作用,而質量濃度為2.2~2.5 mg?L-1的臭氧水既能有效殺滅致病菌又不影響草莓的正常生長,且在一定程度上提高了草莓植株的各項生理指標。
參考文獻:
[1] KIM D R,JEON C W,SHIN J H,et al.Function and distribution of a lantipeptide in strawberry Fusarium wilt disease-suppressive soils [J].Molecular Plant Microbe Interactions,2019,32(3):306-312.
[2] 趙建軍,鄒繼生,陳建德.上海地區(qū)草莓真菌病害的發(fā)生與防治 [J].上海農業(yè)科技, 2014(5):146-148.
ZHAO J J,ZOU J S,CHEN J D.Occurrence and control of strawberry fungal diseases in Shanghai [J].Shanghai Agricultural Science and Technology,2014(5):146-148.
[3] 于飛.無公害草莓病害的綜合防治措施 [J].吉林蔬菜,2017(8):19-20.
YU F.Comprehensive control measures for pollution-free strawberry diseases [J].Jilin Vegetables,2017(8):19-20.
[4] 范麗娟.草莓病害的發(fā)生與防治 [J].種子科技,2019,37(10):116-120.
FAN L J.Occurrence and control of strawberry diseases [J].Seed Science and Technology,2019,37(10):116-120.
[5] ZHANG P W,WANG S Y,HUANG J T,et al.Dissipation and residue of clothianidin in granules and pesticide fertilizers used in cabbage and soil under field conditions [J].Environmental Science and Pollution Research International,2016,19(2):1-7.
[6] PERRY J J,YOUSEF A E.Decontamination of raw foods using ozone-based sanitization techniques [J].Annual Review of Food Science and Technology,2011,2(1):281-289.
[7] USDA.Code of Federal Regulations,Title 9,Part 381.66-Poultry Products;Temperatures and Chilling and Frreezing Procedures [R].Washington D C:Office of the Federal Register National Archives and Records Administration,1997.
[8] 郭正紅,王作銘,殷莉珺,等.臭氧水對紫葉生菜及胡蘿卜軟腐歐氏桿菌的影響 [J].上海師范大學學報(自然科學版),2017,46(5):625-631.
GUO Z H,WANG Z M,YIN L J,et al.Effects of ozone water on growth of Lactuca sativa var. romosa Hort and Erwinia carotovora subsp.carotovora [J].Journal of Shanghai Normal University(Natural Sciences),2017,46(5):625-631.
[9] 郭正紅.臭氧水對設施蔬菜病害的防治及其生理機制的研究 [D].上海:上海師范大學,2017.
GUO Z H.Prevention and treatment of vegetable diseases by ozone water and its physiological mechanism [D].Shanghai:Shanghai Normal University,2017.
[10] 楊葉,周琴,嵇豪,等. 苦瓜枯萎病病菌的分離與鑒定 [J].浙江農業(yè)學報,2010,22(3):354-357. YANG Y,ZHOU Q,JI H,et al.Isolation and identification of Fusarium species from wilted bitter gourd [J].Journal of Zhejiang Agriculture, 2010,22(3):354-357.
[11] ZHAO J N,MA Z,LIU Z P,et al.Pathogenic bacteria of the leaf spot of Neopestalotiopsis clavispora in strawberry [J].Journal of Fungus,2016,35(1):114-120.
[12] 張穎慧,魏東盛,邢來君,等.一種改進的絲狀真菌DNA提取方法 [J].微生物學通報,2008(3):466-469.
ZHANG Y H,WEI D S,XING L J,et al.An improved method of DNA extraction filamentous fungus [J].Microbiology Bulletin,2008(3):466-469.
[13] 王世強.打孔法測定抗生素的效價 [J].生物學通報,2005(3):2.
WANG S Q.The punch method to determine the potency of antibiotics [J].Bulletin of Biology,2005(3):2.
[14] 王孟,李昂,趙震宇,等.裸花紫珠葉抑菌性物質的ASE聯(lián)合牛津杯和微孔刃天青法篩選 [J].時珍國醫(yī)國藥,2017,28(1):43-45.WANG M,LI A,ZHAO Z Y,et al.Screening of bacteriostasis substances of naked flower purple pearl leaves with Oxford cup and microporous blade tianqing method [J].Lishizhen Medicine and Materia Medica Research,2017,28(1):43-45.
[15] 林月莉,黃麗麗,索朗拉姆,等.蘋果輪紋病室內快速評價體系的建立 [J].植物保護學報,2011,38(1):37-41.
LIN Y L,HUANG L L,SOLANGE R,et al.Establishment of apple rapid evaluation system for ring rot disease [J].Journal of Plant Protection,2011,38(1):37-41.
[16] 石凌波,李媛,費諾亞,等.藍莓擬盤多毛孢葉斑病病原菌鑒定 [J].中國南方果樹,2017,46(1):24-28.
SHI L B,LI Y,F(xiàn)EI N Y,et al.Identification of the pathogen of P.hirsutum leaf spot of blueberry [J].South China Fruits,2017,46(1):24-28.
[17] 趙洪海,岳清華,梁晨.藍莓擬盤多毛孢枝枯病的病原菌 [J].菌物學報,2014,33(3):577-583.
ZHAO H H,YUE Q H,LIANG C.The pathogen causing Pestalotiopsis twig dieback of blueberry [J].Journal of Fungi,2014,33(3):577-583.
[18] 溫浩,魏佳爽,張桂軍,等.九種殺菌劑對新擬盤多毛孢病菌的室內毒力作用 [J].農藥學學報,2019,21(4):437-443.
WEN H,WEI J S,ZHANG G J,et al.Laboratory toxicity of nine fungicides against Neopestalotiopsis clavispora [J].Chinese Journal of Pesticide Science,2019,21(4):437-443.
[19] MAHARACHCHIKUMBURA S S N,HYDE K D,GROENEWALD J Z,et al.Pestalotiopsis revisited [J].Studies in Mycology,2014,79(11):121-186.
[20] 趙景楠,馬喆,劉正坪,等.草莓擬盤多毛孢葉斑病的病原 [J].菌物學報,2016,35(1):114-120.
ZHAO J N,MA Z,LIU Z P,et al.Pestalotiopsis clavispora causing leaf spot on strawberry [J].Journal of Fungi,2016,35(1):114-120.
[21] ALEXOPOULOS A,PLESSAS S,CECIU S,et al.Evaluation of ozone efficacy on the reduction of microbial population of fresh cut lettuce(Lactuca sativa) and green bell pepper(Capsicum annuum) [J].Food Control,2013,30(2):491-496.
[22] 孟婷婷,齊鷹博,劉闖,等.樹莓類擬盤多毛孢葉斑病病原菌的鑒定 [J].沈陽農業(yè)大學學報,2020,51(1):111-116.
MENG T T,QI Y B,LIU C,et al.Identification of the pathogen causing raspberry leaf spot [J].Journal of Shenyang Agricultural University,2020,51(1):111-116.
(責任編輯:顧浩然,郁慧)