Maybe Lopes Gonçalves

This study determined optimal fertilization levels for Marandu grass (Urochloa brizantha cv. Marandu) as a forage using sludge from the gelatin industry. The experiment was performed in a greenhouse with five treatments: three rates of gelatin sludge application (0, 200, and 300 m3 ha-1), an organo-mineral (100 m3 ha-1 + mineral: 60 mg dm-3 N), and pure mineral fertilizer (100 mg dm-3 N) with six replicates. Plant and stem height, number of tillers, leaves, leaves/tiller, chlorophyll index, dry mass (leaves, roots, and residue), crude protein, neutral and acid detergent fiber, macronutrient, and micronutrient concentrations were measured. Plant and stem height, number of tillers, leaves, and biomass production increased linearly as gelatin sludge dosage increased. There was a linear increase in crude protein with reduction in neutral detergent fiber and acid detergent fiber with increasing gelatin sludge fertilization. Gelatin sludge dosage did not affect the contents of P, Mg, S, Cu, and Fe. Only Mn had a positive linear response to gelatin sludge with reduction at the highest rate. The 300 m3 ha-1 dosage of gelatin sludge increased biomass production and chlorophyll index. In contrast, the organo-mineral fertilizer promoted higher crude protein and lower neutral detergent fiber concentrations in grass. The gelatin sludge dosage of 300 m3 ha-1 improved the nutritive value of Marandu grass compared to mineral fertilizer. Gelatin sludge is a promising pasture amendment for growing Marandu grass as it recycles industrial animal waste for a more integrated livestock-cropping system.

Gelatin industry residues are increasingly used as fertilizer and soil conditioner. However, correct residue dosage is critical for grass development and minimizing environmental impacts. This randomized block design study determined adequate dosage of mixed gelatin sludge (MGS) for Marandu grass production in wet/dry seasons in Brazil. Five MGS levels (0–200% of required nitrogen) were compared to mineral fertilizer. Agronomic/productivity characteristics, bromatological composition, macro/micronutrient composition of leaves, and soil chemical attributes were evaluated. Agronomic/productivity characteristics were influenced by MGS dose in both dry/rainy seasons, except for leaf blade pseudostem ratio and percentage of leaves/pseudostem. Bromatological composition was influenced by MGS doses in dry/rainy seasons except for dry/mineral material quantities. Marandu leaf tissue chemical composition was significantly influenced by MGS dose, except for potassium, boron, and iron. Chemical composition of four soil layers between 0 and 50 cm influenced MGS dose, except for pH, organic matter, magnesium, copper, manganese, and zinc. GMS dose for Marandu production should be 200% of nitrogen requirement. MGS application increased productivity/quality of Marandu grass. Macronutrients (nitrogen, phosphorus) and micronutrients (calcium, magnesium, sulfur, copper, and zinc) increased in Marandu grass and in the soil (calcium, sulfur, and sodium). The increased sodium level was not limiting.

Gelatin industry residues are increasingly used as fertilizer and soil conditioner. However, correct residue dosage is critical for grass development and minimizing environmental impacts. This randomized block design study determined adequate dosage of Mixed Gelatin Sludge (MGS) for Marandu grass production in wet/dry seasons in Brazil. Five MGS levels (0%–200% of required nitrogen) were compared to mineral fertilizer. Agronomic/productivity characteristics, bromatological composition, macro/micro-nutrient composition of leaves, and soil chemical attributes were evaluated. Agronomic/productivity characteristics were influenced by MGS dose in both dry/rainy seasons, except for leaf blade pseudostem ratio and percentage of leaves/pseudostem. Bromatological composition was influenced by MGS doses in dry/rainy seasons except for dry/mineral material quantities. Marandu leaf tissue chemical composition was significantly influenced by MGS dose, except for potassium, boron, and iron. Chemical composition of four soil layers between 0–50 cm influenced GMS dose, except for pH, organic matter, magnesium, copper, manganese, and zinc. GMS dose for Marandu production should be 200% of nitrogen (N) requirement. GMS application increased productivity/quality of Marandu grass. Macronutrients (N, phosphorus) and micronutrients (Ca, Mg, S, Cu, and Zn) increased in Marandu grass and in the soil (Ca, S, and Na). Increased sodium (Na) level was not limiting.