Effects of Deproteinized Alfalfa Juice Applied to Alfalfa ‐ Bromegrass, Bromegrass, and Corn 1

Autor: Richard P. Walgenbach, H. W. Ream, Dale Smith
Rok vydání: 1977
Předmět:
Zdroj: Agronomy Journal. 69:685-689
ISSN: 1435-0645
0002-1962
DOI: 10.2134/agronj1977.00021962006900040040x
Popis: Nutrient and dry matter losses when harvesting alfalfa (Medicago sativa L) in humid areas of the U.S. are often 15 to 30% or more. A harvesting system designed to minimize these losses, in which standing alfalfa is chopped in the field, pressed to reduce moisture, and the juice processed to extract protein, has been under investigation. When alfalfa is processed in this manner, the products are a pressed forage that is ensiled, a protein concentrate feed, and deproteinized alfalfa juice (DAJ). The DAJ constitutes over half of the weight of the harvested green alfalfa and must be disposed of to avoid pollution problems. Alfalfa requires a high level of soil fertility to produce maximum yields of forage. DAJ contains relatively large amounts of N and K, as well as smaller amounts of P, Ca, Mg, and micro-elements. The objective of these field experiments was to determine the effects of DAJ from first crop alfalfa applied as a fertilizer. DAJ was applied at annual rates of 0, 0.625, 1.25,. and 2.5 cm to an alfalfa-bromegrass (Bromus inermis Leyss.) mixture, pure bromegrass, and corn (Zea mays L.). Increased yields of all three crops were obtained with the annual application of 1.25 cm of DAJ. Plant damage and yield reductions occurred to alfalfa and corn when DAJ was applied at rates of 2.5 cm, with only minor damage to bromegrass. Per hectare yields of crude protein were increased by fertilizing with DAJ. Available P and exchangeable K in the soil generally increased with each increment of DAJ applied, and pH was maintained at satisfactory levels as a result of Ca and Mg additions from DAJ. It was concluded that DAJ applied at rates up to 1.25 cm annually can increase production of alfalfa, bromegrass, and corn. Rates higher than this results in injury or damage to plants, the cause of which has not been ascertained.
Databáze: OpenAIRE