The Effect of Adding Wheat Stalk and Molasses to Potato Leaves and Stems on Silage Chemical Composition and Fermentation Quality

The study investigated the effects of adding wheat stalk and molasses to potato leaves and stems on silage fermentation quality. Potato leaves and stems were treated (fresh weight basis) for ensiling without additives (control), with 20% wheat stalk (W), and with 1%, 3%, and 5% molasses and 20% wheat stalk (WM1, WM3, and WM5, respectively). The nutritional compositions of raw materials and silage and fermentation quality were analyzed. Adding 20% wheat stalk could significantly reduce the pH value and acetic acid content in comparison with no additives. Adding molasses resulted in lower pH value and NH3-N content, higher lactic acid content, compared with the 20% wheat stalk group and the control group. Addition of 5% molasses could result in the highest level of lactic acid content and the lowest pH value and ratio of lactic to acetic acid. Adding 20% wheat stalk could increase the dry matter (DM) content, neutral detergent fiber (NDF) content and acid detergent fiber (ADF) content, decrease the crude protein (CP) content in comparison with no additives. Adding molasses could significantly improve the CP content and reduce the NDF and ADF content compared with the 20% wheat stalk addition group. Generally, applying wheat stalk and molasses additives improved the fermentation characteristics and silage quality of potato leaves and stem, in which the greatest improvement was achieved by adding molasses at 5% to forage mixture containing 80% potato leaves and stems + 20% wheat stalk on a fresh weight basis.