Multivariate analysis is a tool that breeders can use to compare populations and select genotypes for specific purposes. This study used principal component analysis to compare three intraspecific and three interspecific populations of Urochloa spp. based on insect resistance, agronomic, and seed production characteristics. This multivariate strategy exposed completely different profiles and important differences among these populations despite their close genomic ancestry. In general, interspecific populations had greater variability than intraspecific populations for agronomic traits, seed production, and spittlebug resistance. Consequently, crosses among different species, whenever possible, are a better option to obtain new Urochloa breeding populations. However, the breeding of intraspecific populations is also an excellent option to improve specific traits related to each species, which can then be used to speed the breeding in the interspecific programs. Multivariate analysis demonstrated substantial variability within progenies of the interspecific Urochloa populations that can be used to improve insect resistance and productivity of tropical pastures.

中文翻译：

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Urochloa spp。多变量表现：种内和种间种群之间的相似性和差异

多变量分析是育种者可以用来比较种群并为特定目的选择基因型的工具。这项研究使用主成分分析来比较Urochloa spp的三个种内和三个种间种群。基于昆虫的抗性，农艺和种子生产特性。尽管他们具有紧密的基因组血统，但这种多元策略揭示了这些人群之间完全不同的特征和重要差异。一般而言，种间种群的农艺性状，种子产量和抗蚜虫变异比种内种群具有更大的变异性。因此，只要有可能，在不同物种之间进行杂交是获得新的Urochloa的更好选择繁殖种群。但是，种内种群的育种也是改善与每个物种有关的特定性状的极佳选择，然后可用于在种间计划中加快育种。多变量分析表明，种间Urochloa种群的后代内部存在很大的变异性，可用于提高昆虫的抵抗力和热带牧场的生产力。