Selection of conilon coffee clones tolerant to pests and diseases in Minas Gerais

Abstract In the northern Minas region, the dry-warm climate predisposes coffee plants to the occurrence of leaf miners, mites, cercosporiosis, and leaf scald. Aiming for the development of a cultivar adapted to these conditions, Coffea canephora Pierre ex A. Froehner clones were selected through genetic parameters under an irrigated system, without agrochemicals. Eighteen agronomic traits were evaluated. The survival rate, number of nodes per plagiotropic branch, leaf miner infestation and cercosporiosis incidence were chosen as characteristics for selection of ‘Vitória Incaper 8142’, once they have shown superiority of the genetic parameters. The survival rate variable was used to rank the EMCAPA 8141 Robustão Capixaba clones. Clones V2, V4, V6, V13, RC7, and RC9 were selected as more tolerant to pests and diseases and can provide genetic improvements in conilon breeding program for region. The genetic dissimilarity identified between clones allowed suitable clone combinations to be proposed for use in future crosses.

摘要 米纳斯北部区域的干暖气候易使咖啡植株遭受潜叶虫、螨类、尾孢菌病及叶烧病的侵染。为培育适配该生境的咖啡品种，本研究在无农用化学品施用的灌溉体系下，借助遗传参数对中粒咖啡（Coffea canephora Pierre ex A. Froehner）无性系进行筛选。共评估了18个农艺性状，其中成活率、斜生枝节数、潜叶虫侵染率及尾孢菌病发病率因遗传参数表现更优，被选为‘Vitória Incaper 8142’的选育指标。成活率指标被用于对EMCAPA 8141 Robustão Capixaba无性系进行分级。无性系V2、V4、V6、V13、RC7及RC9被筛选为对病虫害耐受性更强的材料，可应用于该区域罗布斯塔（conilon）咖啡育种项目的遗传改良。克隆间鉴定得到的遗传差异性可为未来杂交育种提出适宜的无性系组合方案。