Hanson Peter M, Licardo Olivia, Wang Jaw-Fen, Chen Jen-Tzu
Asian Vegetable Research and Development Center (AVRDC) Shanhua, Taiwan, Republic of China.
Institute of Plant Breeding, University of the Philippines, Los Baños.
Plant Dis. 1998 Jan;82(1):74-78. doi: 10.1094/PDIS.1998.82.1.74.
Bacterial wilt, caused by Ralstonia solanacearum, is a major constraint to tomato production in the tropics and subtropics. Most bacterial wilt-resistant tomato cultivars have not shown consistently high resistance levels over locations. The objective of this study was to determine whether combining resistance derived from different sources would result in F progenies with resistance greater than that of the parents. Five bacterial wilt-resistant tomato lines or accessions (CL5915, L285, CRA84, H7997, and GA219), each derived from different resistance sources, and a susceptible processing tomato line (UC204A) were crossed in all combinations without reciprocals. Parents, F progenies, and F progenies were evaluated in greenhouses at three locations (Taiwan, Philippines, and Indonesia) for percent survival 6 weeks after drench inoculation with virulent local strains of R. solanacearum. Percent survival means over locations were 17.4 to 83.0 for parents and F progeny and 16.2 to 75.0 for parents and F progeny. The percent survival means over locations of L285 × H7997 were highest among crosses in the F (83.0) and F (75.0) generations but were not significantly greater than that of H7997. Highly significant mean squares were found in the F and F progenies for general combining ability (GCA) and GCA × locations. Positive GCA effects over locations were detected for H7997, CRA84, and L285, indicating that progeny with those lines as parents showed bacterial wilt resistance that was greater than the average of all crosses. Only H7997, however, had positive GCA effects estimates at each location for each generation, and its GCA effects estimates over locations were significantly greater than those of the other parents in the F and F progenies. Among this set of parents, H7997 is the best source to develop bacterial wilt-resistant progeny. We did not observe statistically significant increases in resistance by combining different resistance sources. However, the presence of large GCA variances suggests that hybridization of parents that have high GCA for bacterial wilt resistance, such as H7997, CRA84, or L285, followed by selection in segregating populations might yield inbred progeny with resistance greater than that of the parents.
由青枯雷尔氏菌引起的青枯病是热带和亚热带地区番茄生产的主要限制因素。大多数抗青枯病的番茄品种在不同地点的抗性水平并不稳定。本研究的目的是确定将来自不同来源的抗性进行组合是否会产生抗性高于亲本的F代后代。五个抗青枯病的番茄品系或种质（CL5915、L285、CRA84、H7997和GA219），每个都来自不同的抗性来源，与一个感病的加工番茄品系（UC204A）进行了所有组合的正反交。亲本、F代和F代在三个地点（台湾、菲律宾和印度尼西亚）的温室中进行评估，在接种强毒的当地青枯雷尔氏菌菌株6周后测定存活百分比。亲本和F代在不同地点的存活百分比均值为17.4%至83.0%，亲本和F代的存活百分比均值为16.2%至75.0%。在F代和F代中，L285×H7997杂交组合在不同地点的存活百分比均值在所有杂交组合中最高（F代为83.0%，F代为75.0%），但并不显著高于H7997。在F代和F代中，一般配合力（GCA）以及GCA×地点的均方差异极显著。在不同地点检测到H7997、CRA84和L285具有正向GCA效应，表明以这些品系为亲本的后代表现出的青枯病抗性高于所有杂交组合的平均值。然而，只有H7997在每个地点的每个世代都有正向GCA效应估计值，并且其在不同地点的GCA效应估计值在F代和F代中显著高于其他亲本。在这组亲本中，H7997是培育抗青枯病后代的最佳来源。我们没有观察到通过组合不同抗性来源在抗性上有统计学显著的提高。然而，较大的GCA方差表明，将对青枯病抗性具有高GCA的亲本（如H7997、CRA84或L285）进行杂交，然后在分离群体中进行选择，可能会产生抗性高于亲本的自交后代。
