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In long-term field trials at the Dahnsdorf (Fläming) site, investigations have been carried out since 1995 to estimate the necessary level of insecticide application in winter oil seed rape (WOSR) and to develop sustainable insecticide strategies. Within the scope of the trial "Comparison of strategies - environmentally sound crop protection", two different insecticide strategies were compared in WOSR in three trial phases, each of which differed in intensity. The aim of this paper was to compare and discuss these insecticide intensities and their yield and environmental effects against the background of the annual infestation pressure. The evaluation showed that in 21 of 22 trial years considered, insecticide measures were necessary in WOSR, the intensity of which fluctuated considerably due to weather conditions and infestation pressure. It could be shown that a reduction of treatment intensity by 50% to 60% did result in significant yield losses only during the first trial phase. The comparison of the environmental impacts, calculated with the risk indicator model SYNOPS-GIS, showed that the reduction in treatment intensity was accompanied by a reduction in environmental risk over many years. However, individual cases showed that this was not always true and that the choice of agent or active ingredient was also of decisive importance. The results underline the importance of using available decision support tools in crop protection such as infestation controls, warning service, forecasting models and success monitoring to reduce the use of insecticides in WOSR to the necessary need. [ABSTRACT FROM AUTHOR]

In Eternal Rye Trial of Halle/Germany the development of yields is considered for winter rye 1879-2010 and as well as corn and potatoes 1962-2010 to four fertilizer treatments based on decade averages and possible causes for changes in level are mentioned. The yields of winter rye decreased up to 1920, thereafter they remained until the 1960 years more or less constant, and then went up to the present on all variants. In the unfertilized variant, the decade average grain yield was after the start of 22.7 dt/ha, decreased to the 1920 s up to 10.7 dt/ha from and increased from the late 1960 s until the last decade again to 22.2 dt/ha. The causes of the yield drop in the first 40 years after the start of Eternal Rye were mainly in the negative effects of monoculture and the use of seed of the trial area. The yield increase since 1920 were caused mainly by cultivation of new, higher-yielding varieties, regular use of plant protection products and perhaps also by elevated atmospheric CO2 concentration. [ABSTRACT FROM AUTHOR]

Cup plant (Silphium perfoliatum L.) is an interesting energy crop that can be used as substrate in biogas plants. The present study on the cultivation of this crop shall provide knowledge on yield stability and shall demonstrate how many years cup plant can be grown under Bavarian conditions. The results show that under favorable conditions, as for example in the "Straubinger Gäu" region, cup plant can produce high yields of 160 to 220 dt dry matter/ha for several years. However, the total biomass yield of maize was higher in three of four years. The place of origin of cup plant (cultivar) had no effect on yield. Comparing the yield of different experimental sites in Bavaria proved that cup plant can be grown in any Bavarian region where crop cultivation is possible. Nevertheless, high yields will be harvested only on nutrient rich soils with sufficient water supply. [ABSTRACT FROM AUTHOR]

It is likely that climate change will cause an increase in amounts and intensity of extreme weather events. In this review 111 articles of since 1910 globally published literature concerning the effects of extreme weather events on pests affecting wheat, maize, barley, sugar beet, potato, rape, forage crops and grassland were evaluated to gain information about the damage caused, which was that generalized and conclusions for research and adaption measures were drawn. This leads to first evidence that extreme weather effects resulting from climate change indeed have an effect on important plant pests, the damage they cause and plant protection measures in German agriculture. Their influence on said pests, yield, physiological potential as well as stress tolerance of crop plants can be direct or indirect, restricting or supporting, yet no generalizations can be made just based on this first evidence; more intense research in these areas is required. In this article urgency and necessity of research and evaluation of these areas, including systematic interdisciplinary research approaches featuring experimental and model-based methods on multiple experiment levels are discussed. [ABSTRACT FROM AUTHOR]

15 years of meteorological observations at the trial field in Dahnsdorf were used to analyze extreme weather events and their effect on the yields of various crops (winter wheat, winter rye, winter barley, winter oilseed rape, potatoes). The definition of extreme weather events was based on common meteorology threshold values (number of days) and time sequences in which - constantly over several days - the considered area was prevailed by unusual weather conditions. Two hot spells (from 15th July to 14th August 2003 and from 15th July to 01st August 2006), two cold spells (from 01st to 31st January 2010 and from 28th January to 14th February 2012), periods of prolonged drought (from 04th April to 06th May 2007 and from 05th 25th October 2007) and days with downpour were analyzed. The heat spells lasted 31 and 18 days, respectively. The average air temperature was 22.7°C and 23.4°C, respectively; the maximum daily average was 27.9°C and 27.0°C, respectively, the daily maxima were at 34.7°C and 36.6°C, respectively, which were up to 10.0 K above the long-term average. 15 out of 31 and 12 out of 18 days, respectively, were hot days (maxima ≥ 30.0°C). In the cold periods, the daily minimum air temperatures decreased to -18.7°C and -23.6°C, respectively, the daily average to -13.1°C and -19.5°C, respectively. The periods lasted 31 and 18 days, respectively; the recorded average temperatures were -5.2°C and -10.0°C, respectively. The most extreme deviation from the longterm average was -18.2 K. 29 out of 31 and 18 out of 18 days were ice days (maxima < 0.0°C). The considered period from 1998 to 2012 saw three periods with more than 20 days without any rain and another four periods with very low precipitation at the trial field in Dahnsdorf. The longest rainless period lasted 33 days (from 04th April to 06th May 2007). Downpours with daily totals ≥ 50.0 mm were recorded on four days. In the normal value period (1961/90), the reference point at Treuenbrietzen saw only one day in these 30 years. Effects of extreme weather events were analyzed according to defined features resulting from counts (e.g. number of hot days) or time series (e.g. consecutive days ≤ 0.2 mm precipitation, cold periods). They were summarized in four feature groups (icy winters, hot summers, low precipitation during the (main) growing season, heavy precipitation during harvest). The analysis compared the yields of individual crops in the year with the extreme weather event with the respect mean yield of the remaining years. In 2003, extreme weather events of the "Hot Summer" group led to a substantial loss of yields in all crops (winter wheat: 41%; winter rye: 27%; winter barley: 40%; winter oilseed rape: 45%; potatoes: 58%). Significantly lower losses occurred - in similar weather conditions, but with higher precipitation in the (main) growing season - in 2006. Yield losses were also found for the "consecutive days with ≤ 0.2 mm precipitation" group in 2007 (33 consecutive rainless days). The "Icy Winter" group seems to have no or only a slight effect, if it occurs alone. Although both years (2010 and 2012) had a snow cover at the icy winter, the yield was highly variable: While in 2010 after an icy winter some yield losses were still recorded, the yields of the year 2012 with similar weather conditions exceeded the average of the remaining years. Therefore, subsequent weather events in the rest of the year seem to have taken effect on the yield. [ABSTRACT FROM AUTHOR]