Timing of desiccation of distinct cover crops before corn sowing

The timing of desiccation of the cover crop before crop sowing can favor the development of the plants and, consequently, increase yields. The purpose of this study was to evaluate the effects of intervals after desiccation of distinct cover crops and corn sowing on soil fertility, nutritional content and the initial development of corn. The experiment was carried out under controlled conditions in a greenhouse, and consisted of the following treatments: four desiccation periods preceding the corn crop (21, 14, 7 and 0 days), combined with three cover crop species; Crotalaria juncea (Indian hemp), Pennisetum americanum (pearl millet) and Brachiaria brizantha cv. marandu (brachiaria). The longest time interval preceding corn sowing resulted in higher contents of soil organic matter, phosphorus and potassium; the content of these two nutrients was related to the cover crop species. Longer intervals between desiccation and corn planting resulted in greater absorption off, P and K by corn plants. Corn development was also favored by longer periods after cover plant desiccation. An interval of more than 14 days should be maintained to ensure greater nutrient availability for the crop.