Forage yield and structural responses of spineless cactus 'Orelha de Elefante Mexicana' at different planting densities.

The objective was to evaluate the forage yield and structural responses of spineless cactus 'Orelha de Elefante Mexicana' (OEM) (Opuntia stricta (Haw.) Haw) at different planting densities. The experimental design was a randomized block with five treatments and four replicates, during two production cycles of 12 months each. The evaluated densities were 20,000; 25,000; 33,333; 50,000; and 100,000 plants ha^-1. The increase in planting density caused a linear reduction in plant height, width, and mass, as well as in number of primary, secondary, tertiary, and overall cladodes. It also caused a linear increase in cladode area index, dry and green yield, water use efficiency, and forage accumulation rate. The increase in planting density promoted a quadratic effect on cladode thickness and dry matter content. Cladode thickness decreased with planting densities up to 47,500 plants ha^-1 and increased from this point onwards. As for dry matter content, there was an increase up to the planting density of 61,428 plants ha^-1 and a decrease from this point onwards. The increase in planting density of spineless cactus 'Orelha de Elefante Mexicana' caused changes in structural responses and in forage yield. The use of greater planting densities increased forage yield. [ABSTRACT FROM AUTHOR]