Live-Search

Termine

Effects of farmyard manure compost and biodynamic preparations

Long-term trial at IBDF Darmstadt (since 1980)

since 1992 Overview of yields

Third period (research focus: Yield formation and long-term effects)

**Yields (dt ha^-1) as a function of type and level of fertilization, mean values of the crop rotation periods of 1992-95 and 1996-99 (Raupp, 2001)**
	CM	CMBD	MIN	low	medium	high
Winter rye	28.3 a	29.8 a	37.7 b	28.1 a	31.7 b	36.1 c
Spring wheat	38.9	39.3	41.0	36.8 a	40.2 b	42.2 c
Potatoes	247 a	262 b	271 b	230 a	262 b	288 c
Mean values with different letters within a column are significantly different (p<0.05).

The yields of the 3 crops did not respond to fertilization in the same way.
Whereas wheat delivered about the same average yield when fertilized organically or minerally, rye and potatoes achieved higher yields (33 % and 10 %, resp.) with mineral fertilization. The treatment with preparations had a potato yield that was higher by 15 dt ha^-1 over the average of all years. Thus this treatment achieved the same yield level as mineral fertilization.

Increasing fertilizer amounts had positive effects on the yields of all 3 crops.

Searching for factors that have been relevant to yield mainly leads to nitrogen and water supply effects. Yield results can be explained to a large extent by the specific N demand of a crop during the various growth stages and the N availability from organic or mineral fertilizer, resp., during these stages. Besides, considering the mainly dry site conditions, particularly from May to August, a yield reduction caused by lack of water is presumed in almost all years and for all crops. This view is supported by an earlier investigation on the water balance in our soils (Meuser, 1989). However, as a study with spring wheat demonstrated, a favourable water supply seems to be more important for minerally than for organically fertilized plants.

Investigations on special topics included:

Spring wheat: water supply, yield formation in years with extreme conditions
Winter rye: variety choice, sowing date, relevant yield components, N uptake
Occurrence of weeds in wheat and rye
Product quality: durability of potatoes; magnesium contents in red clover

←Vorheriger Nächster→