Andrzej Oleksy

Vertical distribution of dry mass in cereals straw and its loss during harvesting

Abstract The study aimed at evaluating the distribution of mass in the straw of cereal species and also at assessing the straw yield and its losses resulting from the amount of the stubble left in the field. It was found empirically that the wheat culms are composed of five internodes, and in barley, triticale and oats of six. The highest straw mass per 1 cm was found in the second internode in both forms of wheat and winter triticale, whereas barley and oats gathered the highest weight in the first internode. In the southern part of Silesia species and forms of cereals differed in the straw yield, which can be arranged as follows, from the highest: winter wheat > spring wheat, winter triticale, winter barley, and oats > spring barley. Due to the specific distribution of dry matter in each of internodes of both wheat forms - winter and spring, they loose less stubble mass (22 and 24%, respectively), comparing to other cereals, especially spring barley, which loose 31% yield of straw in the stubble of 15 cm height.

Ontogenetic-based sequential path analysis of grain yield and its related traits in several winter wheat cultivars

Studies that provide representative insights for determining yield through its related traits during the ontogeny of modern cultivars subjected to sources of environmental variation are limited for different crops, including wheat. Most of the empirical evidence on the relationships between the yield of small grain cereal crops and its contributing traits has been obtained under dry or semidry conditions. The aims of this paper were to (1) illustrate how an path analysis can be used to clarify and interpret the relationships between grain yield (GY), yield components, and other yield-related traits of 25 winter wheat cultivars subjected to sources of environmental variation and (2) determine how the yield-related traits contribute to the yield variation. The data used in this analysis were generated from multi-environment trials across wheat-growing areas in Poland. Using Ward’s clustering procedure was capable of identifying the most critical predictor traits of the yield components and their contributions to cultivar-focused GY variation. Our findings document, confirm, and improve the basic biological understanding of how to grow modern wheat cultivars for high GY through effectively stimulating the improvement of yield-related traits through the optimization of developmental stage-based agronomic strategies. Our results confirmed empirically that modern European wheat cultivars grown in a temperate climate require favorable conditions, the use of appropriate N fertilizer and growth regulators, and the application of fungicide to protect against leaf diseases and to provide conditions that effectively increase the time to anthesis, the Leaf Area Index per spike at anthesis, and the grain filling duration, and reduce plant height and flag leaf disease severity, thus leading to a high GY. A high yield level is obtained by the performance of preferred yield-related traits that can maintain the three yield components at relatively high levels.

Fusarium head blight incidence and mycotoxin accumulation in three durum wheat cultivars in relation to sowing date and density

Durum wheat (Triticum turgidum var. durum) is an important crop in Europe, particularly in the Mediterranean countries. Fusarium head blight (FHB) is considered as one of the most damaging diseases, resulting in yield and quality reduction as well as contamination of grain with mycotoxins. Three winter durum wheat cultivars originating from Austria, Slovakia, and Poland were analyzed during 2012–2014 seasons for FHB incidence and Fusarium mycotoxin accumulation in harvested grain. Moreover, the effects of sowing density and delayed sowing date were evaluated in the climatic conditions of Southern Poland. Low disease severity was observed in 2011/2012 in all durum wheat cultivars analyzed, and high FHB occurrence was recorded in 2012/2013 and 2013/2014 seasons. Fusarium graminearum was the most abundant pathogen, followed by Fusarium avenaceum. Through all three seasons, cultivar Komnata was the most susceptible to FHB and to mycotoxin accumulation, while cultivars Auradur and IS Pentadur showed less symptoms. High susceptibility of cv. Komnata was reflected by the number of Fusarium isolates and elevated mycotoxin (deoxynivalenol, zearalenone, and moniliformin) content in the grain of this cultivar across all three seasons. Nivalenol was identified in the samples of cv. Komnata only. Genotype-dependent differences in FHB susceptibility were observed for the plants sown at optimal date but not at delayed sowing date. It can be hypothesized that cultivars bred in Austria and Slovakia show less susceptibility towards FHB than the cultivar from Poland because of the environmental conditions allowing for more efficient selection of breeding materials.

A comparison of the chemical composition of the seeds of linseed and pea cultivars grown in pure stands or mixtures

ABSTRACT A three-year field experiment was conducted to compare the chemical composition of the seeds of two linseed-pea mixtures, that is the cv. ‘Flanders’ with the cv. ‘Ramrod’ and cv. ‘Barbara’ with cv. ‘Phönix’. The results indicate that the chemical composition of the seeds of the linseed cultivars was not significantly affected by the sowing method, indicating that the species traits of linseed are constant. The mixed sowing increased the content of threonine and proline in the protein of the Flanders cultivar seeds and slightly increased the protein content of the seeds of both linseed cultivars in the mixtures with pea.

Accumulation of biomass and bioenergy in culms of cereals as a factor of straw cutting height

Abstract Cereal straw is an important biomass source in Europe. This work assessed: 1) the morphological and energetic characteristics of culms of spring and winter cereals, 2) the energy deposited in the different aboveground parts of cereals, 3) losses of energy due to different cutting heights. The straw of winter and spring cereals was collected from arable fields during the seasons 2009/10 and 2010/11 in southern Poland. Detailed biometric measurements of culms and internodes were performed. The losses of straw biomass and energy were assessed during simulation of cutting the culm at different heights, up to 50 cm. Longer and heavier culms were developed by winter wheat and triticale and oat. Cutting of straw up to 10 cm did not lead to significant losses in straw yield. The total amount of energy in the culms was as follows: triticale > winter wheat > oat > spring wheat > winter barley > spring barley. Cutting the culms above 20 cm led to significant differences in terms of biomass energy between cereal species. The smallest losses of energy were recorded for spring and winter barley. Oat and barley accumulated the highest energy in grains.

Agronomic performance of naked oat (Avena nuda L.) and faba bean intercropping

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.