Fenologia e desempenho agronômico de clones de palma forrageira durante o 2º ciclo produtivo

Abstract

The selection of species of forage plants adapted to the Semi-arid climate reduces the impacts promoted by climatic adversities on livestock. This study investigated the performance of six forage cactus clones irrigated in a semi-arid environment. The experiment was conducted at the Center for International Reference for Agrometeorological Studies of Palma and other Forage Plants - Centro REF, Serra Talhada - PE, Brazil. The clones evaluated were: Mexican Elephant Ear (Opuntia stricta (Haw.) Haw.), African Elephant Ear (Opuntia undulata Griffiths), V19 (Opuntia larreri), Miúda (Nopalea cochenillifera (L.) Salm-Dyck), IPA Sertânia (Nopalea cochenillifera (L.) Salm-Dyck) and F8 (Opuntia atropes), arranged in a randomized block design, with three replications, and the evaluations were performed at the clone level. Irrigation was based on 120% of crop evapotranspiration (ETc), adopting the crop coefficient (Kc) of the forage cactus of 0.52. The irrigation system adopted was by drip, with water from artesian well, presenting average electrical conductivity of 1.6 dS m-1. During the experimental period, accumulated precipitation was 1214.5 mm and the total applied irrigation depth was equal to 532.76 mm, totaling 1747.22 mm. For performance analysis, we analyzed: phenology, clade area index, plant stand mortality and green matter and dry matter yield. The data were submitted to variance analysis and Scott-Knott test at the level of 5% probability. The clones OEM and OEA presented fresh matter yield (Y. MF) 3.22 times higher than the average of the other clones (V19, MIU, IPA and F8), for dry matter yield (Y. MS) the averages were 3.39 times higher. Clone F8 showed the highest percentage of plant stand mortality (96.30%). For IAC, there was no significant difference between clones. The number and duration of phenophases varied according to the morphological growth characteristics of each clone. The clones Orelha de Elefante Mexicana (Opuntia stricta) and Orelha de Elefante Africana (Opuntia undulata) presented the highest productive potential compared to the other clones, being the clones most recommended for cultivation in a semi-arid environment.