Crop stability of winter wheat is depending on weather, crop rotation and tillage practices

The work presents the results of experiments with winter wheat from 2015-2020 from the locality Ivanovice na Hané. Wheat was grown on three pre-crops: alfalfa, corn and peas. Each of these variants had four tillage methods (plowing 22 cm, plowing 15 cm, no plowing, disc 10 cm). Grain yield and its quality in relation to the course of the weather and the method of cultivation were evaluated. We evaluated data on the amount of precipitation in mm and air temperature in ºC for the given experimental site, in comparison with the normal (N). Data from 2015 to 2019 for the autumn period from September to December and data from 2016 to 2020 for the months January to June (and also January to July) were evaluated. For winter wheat, it is necessary to evaluate precipitation and temperatures in the period before and after sowing, because the course of autumn affects the sowing date, time of emergence, subsequent rooting and the size of the root system of winter wheat. On average over all 5 years, the yield after maize was reduced to 91.6% compared to peas and to 68.2% after the alfalfa crop. The five-year results presented in the presented work show the great importance of dry autumn for winter wheat and that pre-crops, which deepen the penetration of the soil profile or reduce the availability of moisture by binding water to decompose organic matter, are for subsequent winter wheat in dry years at risk with difficult to correct consequences. Another important factor is the duration of the drought not only in a given year, but also over a period of several years. Prolonged drought deepens the difference between individual pre-crops. The long period of drought, the individual forage crops could not cope as well with the lack of moisture. Alfalfa increased the problem of moisture with its demands on moisture and the decomposition of higher amounts of organic matter. This problem was smaller for corn and the smallest for the pea crop. Yield stability over time is the most important indicator for any factor in cultivation technology. What shows great variability must be monitored and carefully considered whether, given the conditions, it is not what makes the whole system unstable and less successful.