利用植物資源和內(nèi)生真菌防治Meloidogyne incognita效應(yīng)的研究

中文摘要
本文首先以繁殖系數(shù)Rf為指標(biāo)，在盆栽條件下評(píng)價(jià)了南方根結(jié)線蟲(chóng)(Meloidogyne incognita)在7科20種植物上的繁殖能力。其次，從根結(jié)線蟲(chóng)的卵孵化、二齡幼蟲(chóng)的致死率、二齡幼蟲(chóng)侵染、繁殖等方面分別研究了禾草-內(nèi)生真菌共生體及其相應(yīng)的內(nèi)生真菌發(fā)酵濾液對(duì)M.incognita的防治效應(yīng)，其中禾草包括人工栽培禾草(高羊茅)和天然禾草(羽茅、羊草)。最后, 初步開(kāi)展了昆蟲(chóng)病原線蟲(chóng)對(duì)M.incognita趨化性干擾的研究。以上研究拓展了生物防治根結(jié)線蟲(chóng)的視野，有利于綜合控制根結(jié)線蟲(chóng)這一主要病害。
研究結(jié)果表明：
1) 綠架豆是易感寄主；油菜、翠綠青豆、棱形絲瓜、板藍(lán)根、芥菜、四季精選小香蔥、蘇丹草和甜玉米是寄主；紫花苜蓿、八棱脆、黃芩、甜高粱、小麥、葦狀羊茅、金谷2401、高羊茅是弱寄主，對(duì)M.incognita具有一定的抗性；蓖麻、高丹草、黑麥草是非寄主。
2) 人工栽培禾草高羊茅-內(nèi)生真菌共生體對(duì)M.incognita 二齡幼蟲(chóng)(J2)侵染和繁殖具有一定抑制效果，對(duì)J2的趨化性具有一定干擾作用；從共生體中分離的內(nèi)生真菌Neotyphodium coenophialum發(fā)酵濾液對(duì)線蟲(chóng)有致死效果，致死率高達(dá)72.6%。
3) 天然禾草羽茅-內(nèi)生真菌共生體對(duì)M.incognita J2侵染具有一定的抑制作用，從羽茅和羊草-內(nèi)生真菌共生體中分離的內(nèi)生真菌N.sibiricum、Neotyphodium sp.對(duì)二齡幼蟲(chóng)的致死率分別可以達(dá)到66.8%和97.1%。用濃度50% N.sibiricum發(fā)酵濾液處理二齡幼蟲(chóng)后，線蟲(chóng)對(duì)易感植物黃瓜根部的侵染率顯著降低。
4) 初步研究表明，昆蟲(chóng)病原線蟲(chóng)和共生菌對(duì)M.incognita J2具有明顯的趨避效果。

關(guān)鍵詞：南方根結(jié)線蟲(chóng); 繁殖系數(shù); 內(nèi)生真菌; 昆蟲(chóng)病原線蟲(chóng)

 
Abstract
The present study consists of three sections. First, the reproduction of Meloidogyne incognita in 20 plant species belonging to 7 families was eva luated based on the reproduction factor (Rf) in pot trials. Second, potential antagonism towards Meloidogyne incognita of grass–endophyte associations and their corresponding endophytes was eva luated. One cultivated grass Festuca arundinacea ‘Kentucky 31’ and two wild grasses Achnatherum sibiricum and Leymus chinensis were included. The impacts on egg hatching, second stage-juveniles (J2) mortality, J2 chemotaxis, J2 penetration, and reproduction were tested. Finally, the effects of entomopathogenic nematodes on M.incognita chemotaxis were preliminarily conducted. All these studies could give deep insight into root-knot nematode control using biological resources.
The following results were obtained.
1)  Pachyrhizus vulgaris L.was an susceptible host; Brassica napus L,Giycine max(L)Merrill, Luffa cylindrica, Radix isatidis, Brassica napus L.,Allium schoenoprasum L.,Sorghum sudanense (Piper) Stapf. and Zea mays L.were good hosts; Medicago sativa L.,Cucumis melo L., Scutellaria baicalensis Georgi., Sorghum dochna (Forssk.) Snowden, Triticum aestivum L., Festuca arundinacea Schreb., Setaria italica and Festuca arundinacea were poor hosts; Ricinus communis, Lolium perenne L.and Sorghum bicolor x S. bicolor var.Sudanense were assigned as nonhosts.
2)  The cultivated grass tall fescue-endophyte association had negative effects on J2 penetration, J2 chemotaxis and reproduction. Undiluted culture filtrates of endophytic fungi N.coenphialum caused significantly high J2 mortality (72.6%), and the culture filtrates significantly inhibited egg hatching.
3)  Endophyte infected Achnatherum sibiricum was shown to suppress J2 penetration. Undiluted culture filtrates of the endophytic fungi caused significantly high mortality in M. incognita J2, with 91.7% by Neotyphodium sp. associated with Leymus chinesis, and 66.8% by N. sibiricum associated with Achnatherum sibiricum. J2 pretreated by N. sibiricum cultrue filtrates had lower level of penetration, reduced by 44.5%.
 4)  Our preliminary studies indicated that J2 chemotaxis was significantly affected in the pressent of entomopathogenic nematodes and their symbiotic bacteria.

Key words: Meloidogyne incognita; reproduction factor; endophytic fungi; entomopathogenic nematodes

 
目  錄
中文摘要 I
Abstract II
第一章  引言 1
第一節(jié)  根結(jié)線蟲(chóng)的生物特征 1
1.1.1  根結(jié)線蟲(chóng)的形態(tài)特征 1
1.1.2  根結(jié)線蟲(chóng)的生活史及發(fā)病特點(diǎn) 2
1.1.3  根結(jié)線蟲(chóng)的危害 2
1.1.4  根結(jié)線蟲(chóng)的防治現(xiàn)狀 3
第二節(jié)  內(nèi)生真菌 4
1.2.1  內(nèi)生真菌的涵義及特征 4
1.2.2  內(nèi)生真菌和植物寄生線蟲(chóng)防治 5
1.2.3  內(nèi)生真菌抑制線蟲(chóng)的機(jī)制 5
第三節(jié)  本研究意義 7
第二章  多種植物與南方根結(jié)線蟲(chóng)寄主關(guān)系的研究 9
第一節(jié)  材料與方法 10
2.1.1  供試材料 10
2.1.2  試驗(yàn)過(guò)程 10
2.1.3  統(tǒng)計(jì)分析 11
第二節(jié)  實(shí)驗(yàn)結(jié)果 12
2.1.1  不同植物的生長(zhǎng)情況 12
第三節(jié)  分析和討論 16
第三章  禾草-內(nèi)生真菌共生體及相應(yīng)的內(nèi)生真菌對(duì)M. incognita的抗性潛力 18
第一節(jié)  材料與方法 19
3.1.1  供試材料 19
3.1.2  人工栽培禾草高羊茅-內(nèi)生真菌共生體及其相應(yīng)的內(nèi)生真菌對(duì)M.incognita的抗性研究 21
3.1.3  天然禾草-內(nèi)生真菌共生體及其相應(yīng)內(nèi)生真菌對(duì)M.incognita的抗性研究 23
3.1.4  統(tǒng)計(jì)分析 24
第二節(jié)  實(shí)驗(yàn)結(jié)果 24
3.2.1  人工栽培禾草高羊茅-內(nèi)生真菌共生體及其相應(yīng)的內(nèi)生真菌對(duì)M.incognita的抗性研究 24
3.2.2  天然禾草-內(nèi)生真菌共生體及其內(nèi)生真菌對(duì)M.incognita的抗性研究 28
第三節(jié)  分析和討論 33
第四章  昆蟲(chóng)病原線蟲(chóng)對(duì)M.incognita的影響 36
第一節(jié)  材料與方法 36
4.1.1  試驗(yàn)材料 37
4.1.2  試驗(yàn)方法 37
4.1.3  統(tǒng)計(jì)分析 37
第二節(jié)  結(jié)果與討論 37
4.2.1  結(jié)果和討論 37
第五章  結(jié)論與討論 39
第一節(jié)  多種植物與南方根結(jié)線蟲(chóng)寄主關(guān)系的研究 39
第二節(jié)  禾草-內(nèi)生真菌共生體及相應(yīng)的內(nèi)生真菌對(duì)M. incognita的抗性潛力 39
第三節(jié)  昆蟲(chóng)病原線蟲(chóng)對(duì)M.incognita的影響 40
參考文獻(xiàn) 41
致謝 49
個(gè)人簡(jiǎn)歷和在學(xué)期間發(fā)表的學(xué)術(shù)論文與研究成果 50