Beltrán R, Vicent A, García-Jiménez J, Armengol J
Instituto Agroforestal Mediterráneo, Universidad Politécnica de Valencia, Camino de Vera s/n, 46022-Valencia, Spain.
Plant Dis. 2008 Jan;92(1):158-163. doi: 10.1094/PDIS-92-1-0158.
Disease progression and soil population dynamics of Monosporascus cannonballus ascospores were studied and compared through the entire growing season in muskmelon, watermelon, and watermelon grafted onto Cucurbita rootstock crops. In muskmelon and watermelon, there was a decrease of ascospore counts in soil from transplanting until first symptoms of vine decline were observed. This decrease probably was related to ascospore germination and subsequent root infection. Later, there was a remarkable increase of ascospore counts in a parallel way to the quick development of vine decline symptoms, which lead to plant death. In these crops, root colonization adjusted to first-order linear equations and vine decline progression best correlated with exponential and logistic models. In contrast, there were no symptoms of vine decline on grafted watermelon. Furthermore, the isolation of M. cannonballus from Cucurbita roots was considerably lower, perithecia were never observed, and ascospore soil populations remained stable. These results suggest that disease control by grafting onto genus Cucurbita seems to be related primarily by the increased resistance of its root system to infection by M. canonballus, and provide further evidence of the use of grafting as a disease management measure for this disease.
在甜瓜、西瓜以及嫁接于南瓜砧木上的西瓜整个生长季节，对炮弹壳单囊壳菌子囊孢子的病害进展和土壤种群动态进行了研究和比较。在甜瓜和西瓜中，从移栽到观察到藤蔓衰退的最初症状期间，土壤中子囊孢子数量减少。这种减少可能与子囊孢子萌发及随后的根部感染有关。之后，随着藤蔓衰退症状迅速发展并导致植株死亡，子囊孢子数量显著增加。在这些作物中，根部定殖符合一阶线性方程，藤蔓衰退进展与指数模型和逻辑模型相关性最佳。相比之下，嫁接西瓜没有藤蔓衰退症状。此外，从南瓜根部分离出的炮弹壳单囊壳菌数量显著更低，从未观察到子囊壳，且土壤中子囊孢子种群保持稳定。这些结果表明，通过嫁接至南瓜属进行病害防治似乎主要与其根系对炮弹壳单囊壳菌感染的抗性增强有关，并为将嫁接用作该病的病害管理措施提供了进一步证据。
