BIOTECNOLOGIAS APLICADAS NA VIABILIDADE DE PLANTIO DO SORGO FORRAGEIRO PARA PRODUÇÃO DE GRÃOS E SILAGEM EM DIETAS DE RUMINANTES NA MODULAÇÃO DO DÉFICT HÍDRICO NO PERÍODO DA SECA

Abstract

The objective was to evaluate the individual or interaction effects of fertilization with different doses of silicon associated with inoculation with Azospirillum brasilense on the morphoagronomic and productive characteristics and nutritional value of sorghum silages. A randomized block experimental design was used, with 5 replications, in a 4 × 2 factorial scheme, which consisted of the application of 4 doses of Si (0, 4, 8 and 12 kg ha-1) with and without the use of A. brasilense. In relation Regarding productivity and morphoagronomic characteristics were evaluated, water accumulation- AC (Kg/ha), plant height to the flag leaf- ALFB, plant height-ALT, panicle length- CPA, stem diameter- DC, diameter of panicle- DPA, water use efficiency - USA (kg /DM/ mm/ ha), stalk dry matter- MSC, live leaf dry matter- MSFV, panicle dry matter- MSP, whole plant dry matter- MSPI, number of dead leaves- NFM, number of living leaves- NFV, number of grains- NGR, number of reproductive tillers- NPR, number of total tillers- NPT, number of vegetative tillers- NPV, stalk production- PCH (kg /ha), stalk weight- PCOL, leaf production- PFH (kg/ha), dead leaf weight- PFM, live leaf weight- PFV, grain weight- PGR, dry matter production- PMS (kg/ ha), stalk dry matter production- PMSC (Kg/ha), leaf dry matter production- PMSF (kg/ha), panicle dry matter production- PMSP (Kg/ha), green matter production- PMV (kg/ha), panicle weight - PPA, panicle production - PPH (kg/ha). After 105 days the plants were cut at 20 cm from the ground, total feed silage was produced to meet the requirements of beef cattle and dairy goats, as well as sorghum-only silage. After 120 days, the silos were opened and the silages were analyzed for their fermentative quality, evaluating pH, buffer capacity (CT), gas losses (PG), effluent losses (PE), and dry matter recovery (RMS). ), microbial population by evaluating the count of lactic acid bacteria (LAB), molds and yeasts, aerobic stability and chemical composition by analyzing the contents of dry matter (DM), organic matter (OM), mineral matter (GRAY), crude protein (PB), netro detergent fiber (NDF), acid detergent fiber (FDA), hemicellulose (HEM) and lignin (LIG). Regarding the use of A. brasilense, there was a significant effect (p<0.05) for % panicle, ALT (cm). For the use of different doses of SI, a significant effect (p<0.05) was observed for whole plant weight (kg), NFV, PFV (kg), PCOL (kg), PPA, DPA, DC (mm), NGR, PGR, PPA, PCOL. The use of different doses of silicon and the combination or not of inoculation with A. brasilense were not significant (P > 0.05) regarding fermentative quality. For variables related to chemical composition, the treatments evaluated were not significant (P > 0.05). Regarding aerobic stability, it was observed that total ration silages for beef cattle and dairy goats presented greater stability compared to sorghum silage. The use of different doses of silicon associated with inoculation with A. brasilense provided satisfactory results in relation to the morpho-agronomic, productive and quality-related characteristics of the silages. Recommending a dose of 8 kg ha-1 of Si associated with A. brasilense