The Determination of Planting Density on Herbage Yield and Silage Quality of Jerusalem Artichoke (Helianthus Tuberosus L.) Green Mass

Abstract

The aim of this study was to determine green mass yield, silage quality prepared from green mass, nutrient content and digestibility of Jerusalem artichoke (Helianthus tuberosus L.) planted at varying planting densities. Experiment was designed as split plot with four replication and four different plant densities were tested. Planting densities were 70×50 cm (Control), 30×50 cm (Group I), 50×50 cm (Group II), and 85×50 cm (Group III). Chopped green mass were utilized as both silage prepared into 1 L jar-silo and dried original samples. pH of silages were 4.54-4.81 (P=0.5). Lactic acid, acetic acid, propionic acid, and ammonia-N levels were 2.12-4.30%, 1.97-2.32%, 0.29-0.41%, 0.82-1.14%, respectively (P<0.05). Dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), in vitro organic matter digestibility (IOMD), metabolic energy (ME) Mcal/kg values were 29.99-33.28% and 37.05-39.40%; 85.41-85.79% and 86.74-87.88%; 8.58-9.59% and 9.32-11.19%; 35.58-42.53% and 35.19-37.05%; 23.94-30.12%and 23.51-25.08%; 51.71-54.67% and 59.15-63.13%; 1.87-2.012% and 2.139-2.284% for silage and original samples, respectively. Dry matter yields of Jerusalem artichoke ranged from 297.3 to 768.1 kg/da (P<0.01). In conclusion, Jerusalem artichoke as an alternative feedstuff has a forage yield and nutrient content similar to high quality forage. Increasing planting density quadratically increased forage yield. The highest yield was obtained with 50×50 cm planting density. In general, Jerusalem artichoke silage has lower nutrient content, in vitro organic matter digestibility and energy value compared with original sample. Based on this data, Jerusalem artichoke green mass should be preferred to feed to animals as green forage, but can be fed to animals as silage if necessary.