干旱区生态环境知识资源中心

Cactus pear (Opuntia ficus-indica Mill. and Nopalea cochenillifera Salm Dick) has showed high adaptation potential to the Brazilian semi-arid conditions. However, different genotypes have different adaptation characteristics and so different cultivation requirements that need to be known. The objective of this work was to evaluate adaptation potential of six cactus pear varieties used as a forage source of the genus Opuntia (Redonda, Gigante, IPA20, Italiana, Copena V1 and Copena F1) and two of Nopalea (Miuda and Alagoas), assessing the phytomass increments due to rain precipitation responses in the "Cariri" region of Paraiba State, Brazil. Data analyses were carried out using a randomized block design in a factorial arrangement 8 x 2 x 2 (eight cactus forage varieties, two organic fertilization levels, and two mineral fertilization levels), with five replications per treatment. This study took place at the Experimental Station of "Sao Joao do Cariri", from the "Universidade Federal da Paraiba", Paraiba State, Brazil, between August 2004 and January 2007. The morphometry aspects evaluated were: plant height, number of cladodes per plant, cladode length, wide, and thickness; these measurements were made every 28 days to calculate the monthly increments of phytomass. The recorded data were correlated with rain precipitation data of the region in order to obtain the water efficiency use for phytomass increments of these varieties. Results showed that "Italiana" variety presented higher volume of phytomass accumulation and higher persistence under water stress, so better adaptation potential to the semi-arid conditions of the Paraiba State of Brazil. The "Miuda" variety presented the lowest performance. In conclusion, the "Italiana" variety has better adaptation potential to the Paraiba region and so higher forage production under the conditions of this ecosystem.