Viabilidade econômica e eficiência do uso da água na cultura da palma forrageira sob interferência de plantas daninhas e da adubação

Abstract

The present study aimed to analyze the economic viability and efficiency of using water from forage palm, subjected to different periods of weed interference and fertilization. Two experiments were conducted with forage palm culture using a randomized block design. In the first experiment, the economic viability and efficiency of water use in forage palm were studied, subjecting it to 10 periods of weed control (WCP) and 10 periods of weed coexistence (WCoP). The second experiment consisted of an economic analysis of forage palm culture subjected to four types of fertilization: chemical, organic, chemical+organic, and a control group without fertilization. According to the obtained results, net revenues varied depending on the palm's commercialization type and weed control levels. In the first assessment cycle, when production was solely sold as forage, the producer failed to cover the cultivation cost, which averaged R$ 14,288.22. However, combining forage sales with cladode sales yielded profits of up to R$ 114,836.78 with the 0 WCoP treatment. However, the highest benefit/cost ratio (R$ 20.31) was achieved in the second assessment cycle with the 120 WCP treatment. Regarding water use efficiency (WUE) concerning green mass and dry mass production, it is noted that forage palm efficiency was altered depending on the level of competition exerted by weeds. In the second assessment cycle, reductions of 100% in WUE were observed when the culture coexisted with weeds throughout. Regarding the different fertilization types, the average implementation cost was R$ 16,386.92, with net revenues ranging from R$ -8,331.90 for the treatment without fertilization (forage sale only) to R$ 166,251.67 for chemical+organic fertilization (forage and cladode sales combined) in the first assessment cycle. In the second assessment cycle, the lowest net revenue was observed when palm was cultivated without fertilization and solely sold as forage (R$ 6,258.00). In contrast, chemical+organic fertilization resulted in higher production and consequently higher net revenue with forage and cladode sales combined (R$ 175,376.50). It can be concluded that the forage palm culture yielded the highest economic returns when kept free from weed interference throughout and when chemical+organic fertilization was applied, regardless of the final production destination. However, these studies have shown that selling forage combined with cladode sales provides greater profitability for the producer. Keywords: Nopalea cochenillifera, Selling forage, selling cladodes.