Since it has a wide variety, pear can be grown in all temperate zones and high-altitude areas of tropical and subtropical climates of the Earth. On the other hand, most of the cultured pear varieties are susceptible to fire blight caused by Erwinia amylovora, and their susceptibility is threatening pear cultivation. The lack of a certain solution to fire blight, the harmful effects of the chemicals on environment and human health and the increasing demand for organic products, give priority to breeding new resistant rootstocks and varieties in control of the disease. Due to the polygenic nature of fire blight resistance and the complexity of its mechanism, controlled hybridization is generally used in breeding programs. In order to determine the effect of the parents for the transmission of fire blight resistance, hybridizations are also carried out reciprocally. In the study which was carried out for this aim, susceptibility levels of the F1 hybrids, obtained from the reciprocal combinations of fire blight resistant ’Kieffer’ and the susceptible ’Williams’, ’Santa Maria’ and ’Akça’ cultivars, were evaluated. While ’Kieffer’ x ’Santa Maria’ was found the most resistant combination to fire blight, ’Akça’ x ’Williams’ was found as the most susceptible one. In addition, it has been determined that F₁ hybrids obtained from ’Kieffer’ x ’Santa Maria’ and ’Akca’ x ’Williams’ hybridization combinations and their reciprocals are different in terms of disease resistance, while there was no difference in resistance in F₁ hybrids of ‘Williams’ x ’Santa Maria’ combination and its reciprocal combination.

中文翻译：

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从抗病性转移看梨互作的几种组合

由于梨种类繁多，因此可以在地球上所有热带和亚热带气候的温带地区和高海拔地区种植梨。另一方面，大多数养殖梨品种易受两性欧文氏菌引起的火疫病的影响。，并且它们的易感性威胁着梨的种植。缺乏对火疫病的解决方案，化学品对环境和人类健康的有害影响以及对有机产品的需求不断增加，因此优先选择新的抗病砧木和新品种来控制该病。由于抗白叶枯病的多基因性质及其机制的复杂性，育种程序中通常使用受控杂交。为了确定亲本对耐火疫病传播的作用，还进行了杂交。在为此目的进行的研究中，从耐火疫病“基弗”和易感病的“威廉斯”，“圣玛丽亚”和“阿卡”品种的互惠组合中获得了F1杂种的敏感性水平，被评估。发现“基弗”ד圣玛丽亚”对火疫病的抵抗力最强，而“阿卡萨”ד威廉斯”被认为是最易受病害的组合。另外，已经确定F从'Kieffer'x'Santa Maria'和'Akca'x'Williams'杂交组合中获得的_1个杂种在抗病性方面是不同的，而在'Williams'x'的F ₁杂种中抗性没有差异。圣玛丽亚的组合及其对等组合。