【摘要】：近年來,我國秋冬番茄主產(chǎn)區(qū)右江河谷地區(qū)的番茄細菌性斑點病發(fā)病普遍,且日趨嚴重,給種植戶造成較大的經(jīng)濟損失。此病在我國分布范圍廣,發(fā)病嚴重,儼然已成為番茄的重要病害之一。番茄種植過程中選用抗病品種是降低病害發(fā)生的有效手段,國內(nèi)外對此病的抗性育種研究較少,市場上缺少能進行推廣種植的抗細菌性斑點病的番茄品種。對番茄采用人工接種進行抗性鑒定是番茄抗病育種的基礎工作。番茄對細菌性斑點病的抗性表現(xiàn)受到番茄品種、病原菌以及環(huán)境條件的影響,本試驗通過對苗期植株、種子進行接種條件的研究,根據(jù)各接種方法的特點,對主要影響條件進行優(yōu)化,并利用優(yōu)化后的苗期人工接種方法和種子接種方法對74份番茄種質(zhì)進行抗性鑒定,實現(xiàn)抗源的初步篩選,為番茄細菌性斑點病的抗性育種奠定基礎,結(jié)果如下:(1)從田陽縣那坡鎮(zhèn)發(fā)病的番茄植株上分離獲得的菌株,經(jīng)科赫氏法則驗證為致病菌,經(jīng)培養(yǎng)特性、菌體形態(tài)觀察、16s rDNA序列分析等鑒定方法,認定該病原菌為丁香假單胞桿菌番茄致病變種(Pseudomonas syringae pv.tomato)。(2)對前人采用的4種病情指數(shù)分級標準進行對比研究,結(jié)果表明:不同分級標準下的病情指數(shù)之間呈線性或冪函數(shù)關系,試驗建立了不同標準之間的回歸方程,經(jīng)過檢驗,說明函數(shù)模型可靠,可實現(xiàn)不同標準下的數(shù)據(jù)相互轉(zhuǎn)化。(3)對人工苗期接種條件進行優(yōu)化:最佳的接種方法為莖干接種法和針刺葉片接種法,接種苗期為3～5葉期,接種濃度采用1×108cfu/ml,保濕時間在60h以上、溫度在19.5～26.7°C,接種后14±2天進行病情指數(shù)統(tǒng)計。(4)對病原菌接種于種子的可行性進行了驗證,并對種子接種條件進行優(yōu)化,建立了浸種法最適宜接種濃度為1X 109cfu/ml,接種后病情調(diào)查時間在接種后25～30天,接種后環(huán)境溫度維持在23℃～26.7℃。(5)利用優(yōu)化的條件,對74份番茄種質(zhì)進行苗期和種子的抗性鑒定,鑒定結(jié)果表明:在兩種接種方法下,26份番茄種質(zhì)資源的鑒定結(jié)果一致,占鑒定材料的35.14%。苗期莖干接種法中無免疫品種,抗病品種9份,占12.32%,耐病品種22份,占30.13%,感病品種40份,53.42%,高感品種14份,占18.91%;種子浸種接種法中抗病品種13份,17.8%,耐病品種37份,占50.07%,感病品種10份,占13.70%,高感品種14份,占18.91%。
[Abstract]:In recent years, the bacterial spot disease of tomato in Youjiang Valley, the main producing area of autumn and winter tomato in China, is common and serious day by day, which results in a great economic loss to the growers. This disease has become one of the most important diseases of tomato. The selection of resistant varieties in tomato planting is an effective means to reduce the occurrence of disease. There is little research on resistance breeding of tomato in China and abroad, and there is a lack of tomato varieties resistant to bacterial spot disease that can be popularized and planted in the market. The identification of tomato resistance by artificial inoculation is the basic work of tomato resistance breeding. The resistance of tomato to bacterial spot disease is affected by tomato varieties, pathogens and environmental conditions. In this experiment, the inoculation conditions of plants and seeds at seedling stage were studied, according to the characteristics of each inoculation method. The main influencing conditions were optimized, and 74 tomato germplasms were identified by the methods of artificial inoculation and seed inoculation at seedling stage, so as to select the resistant source and lay the foundation for resistance breeding of tomato bacterial spot disease. The results were as follows: (1) the strains isolated from tomato plants in Napo Town, Tianyang County, were identified as pathogenic bacteria by Koch's rule, and identified by culture characteristics and 16s rDNA sequence analysis of cell morphology. The results showed that the disease index was linear or power function relationship between the four disease index classification criteria adopted by the former, the results showed that the disease index was linear or power function relationship under different classification standards. The regression equations between different criteria are established by the test. The test results show that the function model is reliable. The data can be transformed under different standards. (3) the inoculation conditions of artificial seedling were optimized. The best inoculation methods were stem inoculation and acupuncture leaf inoculation. The inoculation concentration was 1 脳 108 cfu / ml, the moisturizing time was more than 60 h, the temperature was 19.5U 26.7 擄C, and the disease index was calculated in 14 鹵2 days after inoculation. (4) the feasibility of inoculating pathogenic bacteria in seeds was verified, and the seed inoculation conditions were optimized. The optimum inoculation concentration of seed soaking method was 1X 109cfu / ml. The investigation time of disease was 2530 days after inoculation, and the environmental temperature after inoculation was maintained at 23 鈩，

本文編號：2141076