Effect of different cutting intensities on morphological characteristics and productivity of irrigated Nopalea forage cactus

Cactus pear (Opuntia ficus-indica Mill) and other cultivated Nopalea forage cacti are considered strategic food reserves for livestock at Brazilian semiarid region as sources of fodder, water, and digestible energy. However, in various locations of this region, these cacti have poor performance due to adverse climatic conditions and inadequate management. The research aimed to evaluate the effect of different cutting intensities on morphological characteristics, production of fresh matter (FMP) and dry matter (DMP) of spineless forage cactus cultivar ‘Miúda’ (Nopalea cochenillifera Salm-Dick) under conditions of irrigation (drip) and fertilization (mineral and organic), with 12 months of regrowth. The experimental design was completely randomized with three harvest intensities (preserving the mother cladode at harvest, preserving all primary cladodes at harvest, and preserving all secondary cladodes at harvest) with 12 replicates. The research evaluated the number of cladodes per plant, cladode dimensions (length, width, thickness, and perimeter), cladode area, cladodes area index, FMP and DMP. A significant effect (P<0.05) of cutting intensity was observed on width, thickness, number of cladodes per plant, cladodes area index, FMP, and DMP. Preserving secondary cladodes resulted in greater FMP (227.67 t ha-1 year-1) and DMP (23.04 t ha-1 year-1) compared to the preservation of primary cladodes (173.11 t ha-1 year-1 of FM and 17.75 t ha-1 year-1 of DM) or preserving only mother cladode (95.09 t ha-1 year-1 of FM and 11.03 t ha-1 year-1 DM). There were no significant differences among the cutting intensities regarding perimeter, length and area of the cladodes, with average values of 51.83, 23.18 cm, and 247.99 cm2, respectively. The preservation of all secondary cladodes at harvest promoted greater number of cladodes per plant and higher forage productivity, and it can be indicated as a management practice.