Sources of phosphorus with sugar cane filter cake on the nutritional status and productivity of sugar cane (Saccharum officinarum L) cultivated in red-yellow latosoil

Abstract Limited sources and phosphorus dynamics in tropical soils justify the search for alternative sources of the element, especially in sugar cane culture. The sugar cane filter cake, a by-product of sugar cane juice filtration is one option, which contains appreciable concentrations of various nutrients including phosphorus, an adequate complement on the use of mineral fertilizers. The effects of phosphorus sources application in different doses combined with sugar cane filter cake were evaluated in sugar cane culture by phosphorus concentrations in soil, plant nutritional status, and stalk productivity. The sugar cane (variety RB86 7515) was cultivated in median texture Dystrophic Red-Yellow Latosoil in an experiment laid out in a randomized complete block design with three replica disposed in a 3x4x2 factorial pattern, comprising three phosphorus sources [Triple Superphosphate (TS), Natural Reactive Bayovar Phosphate (BP) and Natural Araxa Phosphate (AP)], four doses of phosphorus as P 2 O 5 [(0, 90, 180 and 360 kg ha -1 )], combined or not with sugar cane filter cake (7.5 t ha -1 , dry weight). Applications of phosphorus and sugar cane filter cake increased nutrient concentrations in soil, leaves and plant aerial parts by 47.2% (15.4 mg dm -3 ), 7.1% (1.4 g kg -1 ) and 36.3% (10.6 kg ha -1 ), respectively. The sugar cane filter cake alone increased stalk production by 3.4% (122.6 t ha -1 ). TS with sugar cane filter cake combined or its higher doses stood out in all determined properties with the exception in stalk production, which was higher (126.7 t ha -1 ) by application of BP (360 kg ha -1 )