Economically, cacao (Theobroma cacao L.) is a major tropical commodity for the Americas; however, severe losses due to Moniliophthora roreri (Cif. and Par.), which causes frosty pod rot (FPR), and Phytophthora spp., which causes black pod rot (BPR), have reduced cacao production in the Americas. The objectives of this study are to (i) re-confirm the QTL using different marker set; (ii) discover new QTL associated with FPR and BPR resistance using SNP markers; and (iii) find genes in the candidate QTL regions. At CATIE in Turrialba, Costa Rica, an F₁ mapping population of cacao was obtained by crossing “POUND 7,” a clone moderately susceptible to FPR and resistant to BPR, with “UF 273,” resistant to FPR and highly susceptible to BPR. A total of 179 F₁ progeny were fingerprinted with 5149 SNP markers and a dense linkage map composed of 10 linkage groups was developed using 2910 polymorphic SNP markers. Also segregating F₁ trees were screened for resistance to FPR and BPR diseases. Seven QTL previously reported on chromosomes 2, 7, and 8 for FPR resistance and on chromosomes 4, 8, and 10 for BPR resistance were confirmed. Additionally, eight QTL were identified for FPR resistance (chromosomes 4, 9, and 10) and BPR resistance (chromosome 2). The expression of genes commonly associated with plant defense and disease resistance that are located within the identified QTL was confirmed.

从经济上讲，可可（Theobroma cacao L.）是美洲的一种主要热带商品。然而，由于美洲轮虫（Cif。和Par。）造成的严重损失，造成了结霜的豆荚腐烂（FPR），而疫霉属的疫霉菌引起了黑荚果腐烂（BPR），导致美洲的可可豆产量下降。这项研究的目的是（i）使用不同的标记集重新确认QTL；（ii）使用SNP标记物发现与FPR和BPR抗性相关的新QTL；（iii）在候选QTL区域中找到基因。在哥斯达黎加图里亚尔巴的CATIE，F ₁通过将“中等强度”对FPR敏感并抗BPR的克隆“ POUND 7”与对“ FPR”具有抵抗力且对BPR高度敏感的“ UF 273”杂交，获得可可树的图谱种群。用5149个SNP标记对总共179个F ₁后代进行了指纹识别，并使用2910个多态SNP标记绘制了由10个连锁组组成的密集连锁图谱。还分隔F ₁筛选树木对FPR和BPR病的抗性。确认先前在FPR抗性的2号，7号和8号染色体和BPR抗性的4号，8号和10号染色体上报道了七个QTL。此外，确定了八个QTL的FPR抗性（4号，9号和10号染色体）和BPR抗性（2号染色体）。确认了位于已鉴定QTL内的通常与植物防御和抗病性相关的基因的表达。