發(fā)布時(shí)間：2018-04-23 06:40

  本文選題：棉花 + 嫁接　； 參考：《中國(guó)農(nóng)業(yè)大學(xué)》2017年博士論文

【摘要】：為了闡明棉花根系主導(dǎo)型的激素機(jī)制,觀察不同根-冠互作類型形成的機(jī)制,本文采用衰老快的中41和衰老慢的中棉所49(中49)進(jìn)行單接穗單砧木(Ⅰ型)和雙接穗單砧木(Y型)自身嫁接及互相嫁接,在正常供鉀條件下(2.5 mmol/L),所有嫁接處理的葉片衰老程度基本一致;在低鉀脅迫條件下(0.03 mmol/L),以中41為砧木的接穗葉片衰老較快、程度較重,以中49為砧木的相反。因此,中41和中49嫁接組合的葉片衰老根-冠互作類型屬于根系主導(dǎo)型。進(jìn)一步研究表明,以中棉所41為砧木的Ⅰ型嫁接,嫁接后4周其葉片中的ZR+Z(玉米素核苷+玉米素)和iPA+iP(異戊烯基腺嘌呤核苷+異戊烯基腺嘌呤)濃度及接穗木質(zhì)部汁液中的ZR+Z和iPA+iP流量在絕大多數(shù)情況下顯著低于以中49為砧木的處理,ABA(脫落酸)的結(jié)果則相反。雙接穗單砧木(Y型)嫁接的結(jié)果與Ⅰ型嫁接相似,但根系對(duì)葉片衰老的作用未表現(xiàn)出絕對(duì)優(yōu)勢(shì)。為研究葉片衰老不同根-冠互作類型的解剖學(xué)原因,觀察了中41和魯22(地上部主導(dǎo)型)及中41和中49(根系主導(dǎo)型)Ⅰ型嫁接各處理(自身嫁接、互相嫁接)的嫁接體形成過(guò)程。發(fā)現(xiàn)棉花嫁接體愈合過(guò)程可分為3個(gè)階段:(1)隔離層的形成與增厚,砧穗形成初始粘連(嫁接后2d時(shí)),形成層細(xì)胞等脫分化為愈傷組織(少量);(2)愈傷組織大量產(chǎn)生,突破隔離層,隔離層變薄,新的維管組織基本都形成(嫁接后4 d);(3)愈傷組織開(kāi)始分化為新的組織,隔離層基本被吸收,砧木和接穗之間形成連通(嫁接后6 d)。在此過(guò)程中,CTK(細(xì)胞分裂素)和IAA(吲哚乙酸)協(xié)同正調(diào)控愈傷組織形成,促進(jìn)維管組織的修復(fù);ABA對(duì)愈傷組織形成起負(fù)調(diào)控作用,但可能促進(jìn)愈傷組織的分化。葉片衰老不同根-冠互作類型及同一類型不同處理的嫁接體發(fā)育過(guò)程未見(jiàn)明顯差異。此外,觀察2種根-冠互作類型Ⅰ型和Y型嫁接后1-4周各處理砧木和接穗的下胚軸解剖結(jié)構(gòu),結(jié)果表明,嫁接后2-3周Ⅰ型嫁接接穗木質(zhì)部薄壁細(xì)胞的木化程度受砧木影響較大,而導(dǎo)管的發(fā)育主要與由接穗品種決定,Y型嫁接則未表現(xiàn)出這種趨勢(shì)。嫁接后4周地上部主導(dǎo)型Ⅰ型嫁接接穗下胚軸解剖結(jié)構(gòu)與砧木品種更為相似,與其木質(zhì)部CK和ABA的流量主要受地上部調(diào)節(jié)不符;Y型嫁接2個(gè)不同接穗之間下胚軸解剖結(jié)構(gòu)的差異與其木質(zhì)部CK和ABA流量的差異雖然具有一致性但可能是一種伴生現(xiàn)象。嫁接后4周根系主導(dǎo)型Ⅰ型嫁接砧木對(duì)接穗的影響很大,但這與砧木對(duì)接穗下胚軸木質(zhì)部CK和ABA流量的調(diào)節(jié)可能也是一種伴生現(xiàn)象;Y型嫁接2個(gè)不同接穗之間下胚軸解剖結(jié)構(gòu)差異較大,與2者之間CK和ABA流量無(wú)顯著差異的結(jié)果不符。缺鉀誘導(dǎo)條件下,衰老快的中41與衰老慢的魯22和中49分別嫁接后葉片衰老表現(xiàn)出地上部決定型和根系決定型,這兩種根-冠互作方式與接穗下胚軸木質(zhì)部植物激素(ZR+Z、iPA+iP和ABA)流量有關(guān),與嫁接體發(fā)育過(guò)程和嫁接后1-4周下胚軸解剖學(xué)結(jié)構(gòu)發(fā)育無(wú)關(guān)。
[Abstract]:In order to elucidate the hormone mechanism of root dominant type in cotton, the mechanism of root-crown interaction was observed. In this paper, single scion single rootstock (type I) and double scion single rootstock (type Y) were grafted and grafted with each other by using Zhong41 with fast senescence and Zhongmiansuo with slow senescence (Zhongmiansuo 49). Under the condition of normal potassium supplying 2.5 mmol / L, the senescence degree of all grafted leaves was basically the same; under low potassium stress, the senescence of scion leaves with medium 41 as rootstock was faster and heavier than that with Zhong49 as rootstock, and 0.03 mmol / L under low potassium stress. Therefore, the leaf senescence root-crown interaction type of Zhon41 and Zhon49 graft combinations belongs to the root dominant type. Further study showed that type I graft of Zhongmiansuo 41 was used as rootstock. Four weeks after grafting, ZR ZZ (zeatin zeatin) and iPA I (isoamyl adenine) concentration in leaves and ZR Z and iPA IP flow in xylem sap of scion were in most cases. The results of abscisic acid (abscisic acid) treatment were significantly lower than those of Zhong49 rootstock. The result of double scion single rootstock grafting was similar to that of type 鈪，

本文編號(hào)：1790863