Please use this identifier to cite or link to this item:
Breeding for resistamce of watermelon varieties to Fusarium wilt and their genetic analysis of inheritance
|關鍵字:||watermelon;西瓜蔓割病;Fusarium oxysporium f. sp. niveum;race identification;disease resistant variety;root-dipping inoculation method;genetic analysis;RAPD;molecular marker;生理小種鑑定;抗病品種;浸根接種法;遺傳分析;聚合酵素鏈反應;逢機增幅核酸多型性;分子標誌||出版社:||植物病理學系||摘要:||
以Black Diamond、Charleston Gray、Calhoun Gray及PI 296341等四個西瓜品種（系）作為判別植物，進行西瓜蔓割病菌（Fusarium oxysporum f. sp. niveum）之生理小種鑑別，結果證明FNC-0801，FNT-0202及FNH-0103等三菌株均歸屬於Race 0。由感病的Sugar Baby 品種之族群中，選獲抗西瓜蔓割病的自然突變單株，經過6個世代的自交純化，所得的品系暫命名為JSB。它具有極強的抗病性，且與原親本Sugar Baby具有相同的園藝性狀及品質。利用JSB1當作抗病親本與不具抗病性之栽培品種雜交時，其F1世代皆呈現抗病等級，顯示JSB之抗病性，可經由遺傳方式導入西瓜優良栽培品種中。
利用浸根接種法評估國內外128個西瓜品種（系）植株對蔓割病的抗感病性反應。結果顯示JSB, Sugarlee, Crimson Sweet, PI 296341, Charleston Gray, A235-Y及 ND-B等7個品種（系）屬於高抗（HR），其餘有18個屬於中抗（MR），22個屬於中感（MS）及81個屬於感病（S）等級。選取抗病性強的JSB1品系分別與感病品系Sugar Baby （SB1）及Fine Light進行正交〔Sugar Baby （SB1）× JSB1，Fine Light × JSB1〕與反交〔JSB1 × Sugar Baby（SB1），JSB1 × Fine Light〕，取它們的F1與F2雜交後裔，進行病原菌接種檢定，結果顯示正交或反交之F1世代皆呈抗病反應；而F2世代的抗病與感病反應則呈3:1的分離比，證明JSB品系對西瓜蔓割病之抗性係由一對顯性基因所控制。
利用逢機增幅核酸多型性 (random amplified polymorphism DNA，RAPD)技術，針對西瓜抗蔓割病（由Fusarium oxysporum f. sp. niveum Race 0引起）的JSB1品系與其同源感病的Sugar Baby（SB1）品系所純化的模板DNA，進行多型性DNA之篩選。由300個逢機引子，選獲16個多型性片段，再經1-3次篩選，最後獲得Operon G05（OPG05）及Operon Y16（OPY16）兩個引子可在抗病JSB樣品中分別增幅出異於感病Sugar Baby（SB1）樣品的900 bp及800 bp條帶。進一步，以OPY16引子，針對抗病JSB1與感病Sugar Baby（SB1）雜交之F1及F2世代之單株基因組DNA進行多型性分析，發現60個F1世代單株樣品均出現其抗病親本JSB1所特有的800 bp條帶（OPY16800）；至於57個F2世代單株樣品中，卻僅有44個單株樣品出現此條帶，其餘13個樣品均無此條帶，顯示OPY16800核酸片段在F2世代單株樣品中呈3:1的分離比。這種結果恰與西瓜F1、F2苗期的抗感病檢定分離比相吻合。利用選獲的OPY16800分子標誌篩選抗、感蔓割病品種（系），結果顯示OPY16800出現在JSB1、Sugarlee、Charlee、Chrimson Sweet及Charleston Gray等五個抗蔓割病品種（系）上，惟在PI 296341、Dixielee 二個抗病種（系）及Black Diamond與3個Sugar Baby自交系（SB1, SB2, SB3）等四個感病品種（系）上卻未出現此一特殊條帶。此外，利用OPY16800分子標誌檢測西瓜商業栽培品種，結果在新龍（New Dragon）、秀玲（Showing）、黑美人（Dark Belle）、紅鈴（Red Delicious）、新冠（New Crown）、蜜寶（Sugar Baby, F1）及鳳蘭（New Queen）等7個西瓜商業栽培品種均無OPY16800分子標誌顯現。顯然OPY16800可作為西瓜抗蔓割病篩選的RAPD分子標誌，藉以鑑別西瓜品種對蔓割病的抗、感病差異。
Four watermelon varieties, Black Diamond, Charleston Gray, Calhoun Gray and PI 296341 were used as indicator plants for identification of the physiological races of Fusarium oxysporum f. sp. niveum. The results indicated that three isolates FNC-0801, FNT-0202 and FNH-0103 collected from central Taiwan all grouped to Race 0. An individual mutant plant resistant to watermelon Fusarium wilt was derived from the susceptible Sugar Baby population, after six generations of single plant selection and selfing, the line was temporarily named as JSB. The horticultural characteristics and fruit quality of JSB were observed to be identical to Sugar Baby. However, JSB showed highly disease resistant to Fusarium wilt. All F1 progenies from the crosses between JSB and six susceptible inbred lines were resistant to Fusarium wilt. The results suggest that the disease resistance of JSB can be transferred to other superior inbreds of watermelon and JSB can be used as one of parent for breeding new disease-resistant watermelon varieties.
Evaluating of the response to Fusarium wilt disease caused by Fusarium oxysporum f. sp. niveum Race 0 in 128 watermelon varieties (lines) was conducted by the root-dipping inoculation method. The results showed that 7 out of 128 varieties (lines) were highly resistant (HR), 18 varieties (lines) were moderately resistant (MR), 22 varieties (lines) were moderately susceptible (MS), and 81 varieties (lines) were susceptible (S), respectively. In order to study the inheritance of Fusarium wilt resistance in watermelon, progenies of the F1 and F2 generations from the crosses between one resistant inbred line, JSB1, and two susceptible inbred lines, Sugar Baby (SB1) and Fine Light (FL) were obtained. All the F1 plants were resistant to Fusarium wilt and the F2 populations of SB1 × JSB1 and FL × JSB1, as well as their reciprocal crosses JSB1 × SB1 and JSB1 × FL, showed a 3:1 (resistant:susceptible) ratio by χ2 analysis. The results suggested that the resistance of Fusarium wilt in JSB watermelon variety is controlled by a single dominant gene.
A random amplified polymorphic DNA (RAPD) analysis was conducted to screen the polymorphic DNAs from two watermelon mutants, Fusarium wilt-resistant JSB1 and susceptible Sugar Baby (SB1), with 300 decamer primers in this study. Sixteen polymorphic fragments were produced by RAPD analysis. These 16 polymorphic fragments were futher confirmed 1-3 times by RAPD analysis and finally primers OPG05 and OPY16 were selected. OPG05 and OPY16 primers clearly distinguished the wilt-resistant JSB1 from the susceptible Sugar Baby (SB1, SB2, SB3) by producing one more band located at 900 bp (OPG05900) and 800 bp (OPY16800), respectively, in the PCR products of JSB1. These bands might be related to Fusarium wilt resistant genes. In order to study the inheritance of Fusarium wilt resistance in watermelon, the F1 and F2 generations from the crosses between resistant inbred line, JSB1, and susceptible inbred line, Sugar Baby (SB1), were obtained. The genomic DNA from Sugar Baby (SB1) × JSB1 and their F1 and F2 individual watermelon plants were subjected to RAPD analysis with OPY16 primer. The results indicated that OPY16800 fragment was present in all F1 and in 44 out of 57 of the F2 progenies. This fragment was absent in the other 13 F2 progenies of Sugar Baby (SB1) × JSB1. The segregation of the progenies showed a 3:1 ratio (resistant:susceptible). The result is in good aggrement with the evaluation results for Fusarium wilt resistance of previous watermelon seedling test. Thus, OPY16800 can be used as a molecular marker to differentiate between disease resistant line JSB and susceptible line Sugar Baby. OPY16800 was also present in Fusarium wilt-resistant watermelon varieties such as Sugarlee, Charlee, Chrimson Sweet, Charleston Gray, but not in any susceptible varieties tested in this study. In addition, the OPY16800 molecular marker did not present in 7 susceptible commercial varieties. Therefore, OPY16800 could be used as a molecular marker to screen for Fusarium wilt resistant cultivars/lines in watermelon. It also can be applied to differentiate disease-resistant from disease-susceptible watermelon varieties/lines.
|Appears in Collections:||植物病理學系|
Show full item record
TAIR Related Article
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.