The association between morphological characteristics and yield in forage cactus clones varies according to water regimes: a principal component analysis

Forage cactus species exhibit distinct morphological characteristics, which have a relationship to yield and can be affected by different water conditions. The objective was to analyze, with the principal components analysis (PCA), the association between morphological and productivity variables in forage cactus clones in different water regimes. We cultivated, in Serra Talhada, Brazilian semiarid, the Miúda (MIU), Orelha de Elefante Mexicana (OEM) and IPA Sertânia (IPA) clones under four water regimes based on crop evapotranspiration – ETc (0%, 40%, 80% and 120% ETc). Between the years 2016 and 2018, morphological and crop productivity data were obtained. Two main components explained >82% of the total variability of the data, and the relationship between morphological and production variables depended on the clone and the water regime. The production of fresh and dry matter was more influenced by the morphological characteristics in the MIU and OEM clones. The IPA clone showed no correlation between the variables analyzed, regardless of the water regime. PCA can be used to understand the growth dynamics of plants and to identify the water conditions that act in the production of cactus clones, favoring better management in the cultivation of culture.