Abstract #T75
Section: Forages and Pastures (posters)
Session: Forages and Pastures 1
Format: Poster
Day/Time: Tuesday 7:30 AM–9:30 AM
Location: Exhibit Hall A![](/2019/images/btn-find-it.png)
Session: Forages and Pastures 1
Format: Poster
Day/Time: Tuesday 7:30 AM–9:30 AM
Location: Exhibit Hall A
![](/2019/images/btn-find-it.png)
# T75
Effect of hybrid and planting density on yield and nutritive value of whole plant sorghum forage.
C. L. McCary*1, C. Heinzen Jr.1, L. Brown2, E. M. Paula1, D. M. Taysom3, L. F. Ferraretto1, 1University of Florida, Gainesville, FL, 2Advanta Seeds, Irving, TX, 3Dairyland Laboratories Inc, Arcadia, WI.
Key Words: plant population, yield, nutritive value
Effect of hybrid and planting density on yield and nutritive value of whole plant sorghum forage.
C. L. McCary*1, C. Heinzen Jr.1, L. Brown2, E. M. Paula1, D. M. Taysom3, L. F. Ferraretto1, 1University of Florida, Gainesville, FL, 2Advanta Seeds, Irving, TX, 3Dairyland Laboratories Inc, Arcadia, WI.
The objective of this study was to evaluate the yield and nutritive value of 2 sorghum hybrids (Advanta Seed Alta AF7401 [H1] and Alta XF372 [H2]) planted at densities of 148,260 (D1), 197,680 (D2), 247,105 (D3), 296,526 (D4) and 345,947 (D5) seeds/hectare on yield and nutritive value of whole-plant sorghum forage. The treatments (2 hybrids [H] x 5 plant densities [PD]) were randomly distributed in 4 replicate plots. Plots consisted of 4 rows spaced at 0.762 m apart, at a length of 6.096 m per row. Plots were harvested targeting 31% dry matter (DM). At harvesting, the 3 outermost plants in the center 2 rows were discarded and all remaining plants in a 3-m linear distance were collected, chopped and weighed to calculate yield within the respective row. Subsamples were collected and dried in a forced air oven at 60°C for 48 h for DM determination. Dry samples were then ground to pass through a 4 mm sieve and sent to Dairyland Labs (Arcadia, WI) for nutrient analysis and predicted ruminal in vitro NDF digestibility at 30h (NDFD) using a near infrared spectrometer. Estimated milk production per unit of forage (kg of milk/Mg of forage) or per hectare (kg of milk/ha) were based on the predictive equations of Milk2006. Data were analyzed using PROC GLM of SAS in a complete randomized design with a 5 × 2 factorial arrangement with fixed effects of hybrid, planting density and their interaction. A single H × PD interaction was observed in lignin (P ≤ 0.01), otherwise only main effects will be discussed. Greater concentration of aNDF (P < 0.01) and NDFD (P < 0.01), but lower starch concentration (P < 0.01) was observed for H1. Additionally, H2 had greater yield of DM (P < 0.01), and milk production estimates per unit of forage (P ≤ 0.03), and hectare (P < 0.01). As PD increased, the concentration of aNDF (P ≤ 0.01) increased as well. Greatest milk estimates (kg of milk/Mg of forage; P value ≤0.01) was observed at D1 and reduced gradually with increasing PD. These results emphasize the effect of hybrid and planting density on yield and nutritional value in whole plant sorghum forage.
Key Words: plant population, yield, nutritive value