Organic matter fertilization improves morphological variables in Nopalea cochenillifera Salm Dyck cv. Miúda grown as forage in Pernambuco, Brazil

Abstract

In forage crops such as cactus morphological characteristics respond to management practices such as fertilization. An evaluation was done to determine if organic matter (OM) fertilization (0, 10,000, 20,000 and 30,000 kg OM ha-1 yr-1 bovine manure), mineral fertilization (0, 120, 240 and 360 kg N ha-1 yr-1, using urea) and cut frequency (annual and biennial) influenced cladode length, width and perimeter, and Cladode Area Index (CAI) values in Nopalea cochinillifera Salm Dyck cv. Miúda, and how these variables related to productivity. The experimental design was random blocks, using a sub-sub-plot arrangement with four replicates. Fertilization with 30,000 kg OM ha-1 year-1 increased cladode width by 9.8 % and length by 17.8 % compared to the control. Cladode perimeter increased proportionally to OM fertilization level. At the optimum fertilization level (25,970 kg ha-1) the CAI value was 68.29 % higher than the control. Mineral fertilization only affected cladode perimeter at 120 kg ha-1 and only with an annual cut; however, at this fertilization level the CAI value was higher with a biennial cut. Organic matter fertilization increased cladode width and length, and CAI values in N. cochenillifera cv. Miúda, while mineral fertilization had only a minimal effect. Biennial cutting frequency results in higher CAI values. Correlations were high between the evaluated variables and dry matter production, highlighting the utility of morphological variables in evaluating productivity.