Avaliações morfológicas, produtivas e qualitativas de progênies de palma forrageira V-19 (Opuntia lorreyi F. A. C.)

Abstract

Cactus pear is an important forage resource for semi-arid region. However, in the last years, most of the palms of Pernambuco and Paraíba were decimated by the carmine cochineal (Dactylopius opuntiae Cockerell), making the focus of the breeding program the development and introduction of cultivars resistant to this pest. Alternatives besides the traditional ones like chemical and physical control are little efficient, for which there is a need to find resistant varieties to the insect. The objective of this study was to evaluate the progenies of the V-19 cactus pear (Opuntia lorreyi F.A. C), in terms of its morphological, productive and nutritional value. The experiment was carried out at the Experimental Station of the Agronomic Institute of Pernambuco - IPA in Arcoverde-PE/Brazil. Eleven genotypes of V-19 (Opuntia lorreyi F.A C) were used, being 10 progenies (P1, P2, P3, P4, P5, P6, P7, P8, P9 and P10) from free pollination with seven replicates. For the morphological and productive characteristics, two evaluations corresponding to the first and second harvest and four intermediate evaluations were carried out: height and width of plant (PH and PW), number, height, length, width, perimeter of cladode (CN, CH, CL, CW, CP), cladode area and cladode area index (CA and CAI), and productivity. The dry matter (DM), mineral matter (MM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), ethereal extract (EE) ), total carbohydrates (CHT), nitrogen (N), potassium (K), phosphorus (P), calcium (Ca) and in vitro dry matter digestibility (IVDMD). The experimental design was a completely randomized design with seven replicates. The data were analyzed as measures repeated in the time, being the pre-harvest evaluations, the intermediate evaluations and the harvests the measures considered. The values of number of secondary and tertiary cladodes (CN), perimeter, length and width of secondary cladodes, plant height and width (PH and PW), cladode area, cladode area index (CAI) and dry matter yield (DMY) obtained in the second pre-harvest and harvest were considered high. For the variables related to the nutritive value (MM, NDF, ADF, PC and P), the values obtained in the first harvest were higher when compared to the second. The P1 and P9 progenies stood out in relation to the progenitor in the morphological and productive evaluations; however, for the nutritional value variables the progenies were P1, P2 and P3. It is recommended the continuity of the studies with the materials that stood out, mainly evaluating the responses to different densities, fertilization, as well as the consumption of dry matter and nutrients with ruminant animals.