Effect of plant spacing and cutting intensity on the morphology and productivity of forage cactus [<i>Opuntia stricta</i> (Haw.) Haw.

Abstract

The forage cactus cultivar Mexican elephant ear (MEE) [Opuntia stricta (Haw.) Haw.] has been widely used in the semi-arid of Brazil  because of its resistance to carmine mealybug. Therefore, it is necessary to establish planting and harvesting management strategies for  this cultivar. This study evaluated the effect of cutting intensity (preservation mother cladode, and mother + primary cladodes) and  different planting densities (55 555; 27 777; 13 888 and 6 944 plants ha⁻¹) on the morphology and productivity of the forage cactus cv.  MEE, in 10-year-old cultivation under rainfed conditions. A split-plot design was used where planting density was allocated to the main  plots and harvesting intensity to the sub-plots. Each treatment combination was replicated four times. The data were submitted to  ANOVA, Tukey’s test, and principal component analysis at 5% (p < 0.05). Post-harvesting preservation of the primary cladodes promoted  greater dry matter production (9.2 t ha⁻¹ year⁻¹), crop water accumulation (86.6 t ha⁻¹ year⁻¹), and rainwater use efficiency (11.4 kg of  DM mm⁻¹) (p < 0.01). Primary cladodes preservation positively influenced the productive characteristics of the forage cactus, and the  planting density of 13 888 plants ha⁻¹ (0.72 m2) favoured the productivity of this cultivar. These findings can guide planting and   harvesting strategies for cultivating MEE cactus.