Agronomic characteristics and nutritional value of cactus pear progenies

Abstract

Cactus is an important fodder in tropical semiarid, but recent insect pressure has devastated cactus crops. Breeding programs are developing cactus varieties resistant to cochineal scale (Dactylopius opuntiae Cockerell). The cactus V‐19 (Opuntia larreyi F.A.C. Weber ex J. M. Coult.) has demonstrated resistance to cochineal scale, however, no breeding effort has been attempted with this species. This study characterized the resistance of cactus V‐19 progenies to cochineal scale. Morphological, productive, and nutritive value variables were evaluated in 11 genotypes of cactus V‐19, in which 10 (named as P1, P2, P3, P4, P5, P6, P7, P8, P9, and P10) were progenies resulted from open pollination. Two evaluations were carried out from 2015 to 2017, corresponding to first and second harvest years. A randomized complete design with seven replications were used. There was a harvest (year) × progeny interaction (p < .05) across the estimated parameters. In 2017, there was a stronger correlation between morphological traits and productive responses because cactus had faster growth and greater number of cladodes, while in 2015 progenies had greater nutritive value. Progeny P1 improved performance compared with the progenitor and other progenies regarding dry matter (DM) accumulation, in vitro digestible DM, and crude protein with 13.7 Mg DM ha–1 year–1, 848 g kg–1, and 47 g kg–1, respectively. The principal component analysis (PCA) and dendrogram obtained by hierarchical clustering method confirmed that progeny P1 outperformed the other progenies, including the mother plant V‐19. These progenies must be further evaluated to assess their productive responses under different management practices.

Does Maturity Change the Chemical-Bromatological Makeup of Cladodes in Spineless Forage Cactus?

“…Hays often vary from 4 to 20% [39]. Despite accessions and cladode maturity phases, CP in spineless forage cactus was extremely low in our results (<6%), which represents the lowest quality forage according to general forage quality standards for livestock diets [35]. However, low CP levels can be improved through nutrient management practices.…”

“…Santos et al [33,34] found 12% and 11.9% MM in spineless forage cactus studies. An average cladode MM concentration (15.7%) was reported by Garcia et al [35]. Spineless forage cactus frequently recorded high mineral concentrations attributed to the necessity for stomatal regulation and other physiological processes [36,37].…”

“…Unlike ADF, it is unrelated to quality and digestibility. In most forages, values typically fall between 50 and 80% [35]. Compared to grasses, legumes often have lower NDF and ADF levels and as forage maturity rises so do these values.…”