Biomass yield and energy efficiency of willow depending on cultivar, harvesting frequency and planting density | Bogdan Kulig, Edward Gacek, Roman Wojciechowski, Andrzej Oleksy, Marek Kołodziejczyk, Wojciech Szewczyk, Agnieszka Klimek-Kopyra | Agricultural Journals

The most common cereals for faba bean (Vicia faba L.) used in intercrops is conventional oat (Avena sativa L.) An alternative to oat may be naked oat (Avena nuda L.), whose oil content and quality is double. Here, intercropping of naked oat with two different faba bean cultivars (determinate-high tannin and indeterminate-low tannin) was compared with sole crops of each species in 2006-2008. The treatments were: sole naked oat at 500 kernels m², indeterminate sole faba bean at 50 seeds m², determinate sole faba bean at 70 seeds m², and an additive series of 25%, 50%, and 75% of faba bean seeding rate mixed with the naked oat seeding rate. Our results demonstrated that intercropping increased the Land Equivalent Ratio by +3% to +9% over sole cropping. Raising the faba bean seeding rate in a mixture from 25% to 75% reduced oat grain yield from 630 (determinate cultivar) to 760 kg ha-1 (indeterminate cultivar) but increased faba bean grain yield from 760 kg ha-1. Higher yield and leaf area index (LAI) and photosynthetically active radiation (PAR) values show that the indeterminate cultivar of faba bean is more suitable in mixture with naked oat. The high value of competition index (CR > 1) indicates domination and aggressiveness of faba bean towards naked oat. Regardless of cultivar type, mixture of faba bean with naked oat is less productive than pure sowing

Soybean yield is the result of the interaction of environmental factors and agricultural practices. Agricultural practices developed for soybean assume optimal cultivation conditions. Aberrant rainfall distribution during the growing season reduces the productivity of the plants and the efficiency of N uptake, which is reflected in the seed yield and quality. Few studies in the literature focus on this question. Therefore, the purpose of this assessment was to compare yield, yield quality of two soybean cultivars (Augusta and Mavka) with two nitrogen application rate (basic and increased) and two date of sowing (early and late), in two-year field experiments under temperate zone conditions in central Europe. Results show that early sowing in combination with higher nitrogen application substantially improves crop productivity and the efficiency of nitrogen binding, especially in drought years. In contrast, delaying sowing by two weeks reduced the productivity of the plants, which was not compensated for by a higher level of mineral nitrogen application. Early sowing of the Mavka cultivar was more productive and more efficient in nitrogen accumulation in the seed yield in comparison to the Augusta cultivar. Under water deficit conditions a higher level of urea application and earlier sowing are recommended.

Recent years have seen a significant increase in weather anomalies in Central Europe (51°22′ N, 22°64′ E), which makes it more difficult to predict yields of winter wheat and to estimate prices on world exchanges. Eight-year (2007–2015) field observations of winter wheat cv. Turnia were carried out in order to determine the relationship between selected meteorological indicators (e.g., the values of average daily air temperature, daily sums of precipitation, and the number of days with precipitation) and the biometric traits and seed yield of winter wheat. In addition, an attempt was made to identify the meteorological parameters that determine an increase in stem elongation during the growing season. The relationship between yield parameters and biometric parameters was evaluated using Spearman’s non-parametric correlation coefficients. The regression models for analysis of the dependence of yield parameters and biometric parameters on meteorological elements (temperature, precipitation totals, and days with precipitation) in each development period was used. The study showed that from the beginning of vegetative growth to the flowering stage, growth and development were most advanced in plants for which the average temperature was about 8–9 °C, and the number of days with precipitation was about 41. During generative growth, spike length is 80% determined by the precipitation total. Grain weight is 68% negatively determined by the temperature during dormancy (the higher the temperature during dormancy, the lower the weight of the kernel). A positive relationship was shown between yield and the precipitation total during the period from sowing to the onset of dormancy (r = 0.37). Winter wheat yield was 69% dependent on the density at harvest (the greater the density, the higher the final yield). On the basis of the 8-year results of the study, we conclude that the weather is highly variable from year to year, and therefore breeders should direct their research towards creating variants with much greater plasticity and high tolerance for unfavourable weather patterns.