Grain legumes in mixed stands with false flax (Camelina sativa) in organic farming under Pannonian site conditions

In drei aufeinander folgenden Versuchsjahren wurden die Körnerleguminosen Linse (Lens culinaris), Platterbse (Lathyrus sativus) und Futtererbse (Pisum sativum) als Reinsaat und in unterschiedlichen Mischungsverhältnissen gemeinsam mit Leindotter (Camelina sativa) in einem Feldversuch auf den ökologisch bewirtschafteten Versuchsflächen der Universität für Bodenkultur Wien im pannonischen Klimagebiet geprüft. Ziel dieses Versuchs war zu überprüfen, ob unter trockenen Standortbedingungen eine Körnerleguminosen-Leindotter-Mischkultur trotz der erhöhten Konkurrenzsituation zwischen den Mischungspartnern vorteilhaft ist. Dafür wurden die optimalen Saatmengen von Leindotter und Körnerlegumi­nosen als Mischungspartner unter den pannonischen Bedingungen ermittelt. Die Witterungsverhältnisse waren in den drei Versuchsjahren sehr unterschiedlich und beeinflussten die Ertragsdaten der Mischkulturen. Unter den günstigen Witterungsbedingungen im ersten Versuchsjahr zeigten die Mischungen von Leindotter-Linse und Leindotter-Platterbse ertragliche Vorteile. Im Mittel über die drei Versuchsjahre war eine Leindotter-Linsen Mischung von 25:75 Prozentanteilen die Mischung mit dem günstigsten Mischungseffekt. Leindotter in den Mischkulturen erzielte durchschnittlich 6 dt ha–1 in den Mischungen mit Linsen sowie in den Mischungen mit Platt- und Futtererbse bei hohem Leindotteranteil. In Summe war der positive Effekt der substitutiven Lein­dotter-Linse und Leindotter-Platterbse Mischungen in den günstigen, feuchten Jahren größer als der negative Effekt im ungünstigen, trockenen Jahr. Diese Leindotter-Körnerleguminosen Mischungen werden deshalb sowohl für das Trockengebiet Ostösterreichs als auch für klimatisch ähnliche Gebiete in Ungarn oder Mitteldeutschland empfohlen.The grain legumes lens (Lens culinaris), grass pea (Lathyrus sativus) and field pea (Pisum sativum) were examined as pure crops and in different mixing ratios with false flax (Camelina sativa) on organically cultivated fields of the University of Natural Resources and Life Sciences, Vienna, in the Pannonian region in three consecutive vegetation periods. The aim of this study was to test whether a mixed stand of grain legume and false flax shows advantages compared to the pure crops despite an increased competition between the partners in the mixture under the dry conditions. Therefore, the optimum seed density for the partners in the mixed stand under the Pannonian conditions was identified. The weather conditions varied widely within the three vegetation periods and influenced the yield of the mixtures. Under the favourable weather conditions in the first experimental year, the mixed stands of lens-false flax and grass pea-false flax showed benefits in yield. On average across three very different years, a mixture of false flax : lens at 25:75 percent had the most positive mixture cropping effect. An average of 0.6 t ha–1 false flax was achieved in mixed stands with lentils and in mixtures with grass pea and field pea with high false flax percentage. In general, the positive effect of the substitutive lens-false flax and grass pea-false flax mixed stands was higher in the favourable, wet years than the negative effect in the unfavourable, dry year. We therefore recommend these grain legume-false flax mixed stands for the dry regions in Eastern Austria and for climatically similar regions in Hungary or Central Germany

Co-occurrence of Mild Salinity and Drought Synergistically Enhances Biomass and Grain Retardation in Wheat

In the present study we analyzed the responses of wheat to mild salinity and drought with special emphasis on the so far unclarified interaction of these important stress factors by using high-throughput phenotyping approaches. Measurements were performed on 14 genotypes of different geographic origin (Austria, Azerbaijan, and Serbia). The data obtained by non-invasive digital RGB imaging of leaf/shoot area reflect well the differences in total biomass measured at the end of the cultivation period demonstrating that leaf/shoot imaging can be reliably used to predict biomass differences among different cultivars and stress conditions. On the other hand, the leaf/shoot area has only a limited potential to predict grain yield. Comparison of gas exchange parameters with biomass accumulation showed that suppression of CO2 fixation due to stomatal closure is the principal cause behind decreased biomass accumulation under drought, salt and drought plus salt stresses. Correlation between grain yield and dry biomass is tighter when salt- and drought stress occur simultaneously than in the well-watered control, or in the presence of only salinity or drought, showing that natural variation of biomass partitioning to grains is suppressed by severe stress conditions. Comparison of yield data show that higher biomass and grain yield can be expected under salt (and salt plus drought) stress from those cultivars which have high yield parameters when exposed to drought stress alone. However, relative yield tolerance under drought stress is not a good indicator of yield tolerance under salt (and salt plus drought) drought stress. Harvest index of the studied cultivars ranged between 0.38 and 0.57 under well watered conditions and decreased only to a small extent (0.37-0.55) even when total biomass was decreased by 90% under the combined salt plus drought stress. It is concluded that the co-occurrence of mild salinity and drought can induce large biomass and grain yield losses in wheat due to synergistic interaction of these important stress factors. We could also identify wheat cultivars, which show high yield parameters under the combined effects of salinity and drought demonstrating the potential of complex plant phenotyping in breeding for drought and salinity stress tolerance in crop plants

Common bunt in organic wheat: unravelling infection characteristics relevant for resistance breeding

Common bunt caused by Tilletia tritici and T. laevis has re-emerged as a major threat to wheat yield and quality, especially in organic farming. Resistance against its causal agents is present in the wheat gene pool and provides the most economically efficient and sustainable way to combat the disease since seed treatments approved for organic farming are rare and do not always provide full protection. We tested a winter wheat diversity panel with 128 lines for common bunt resistance in Austria and Czechia, and evaluated the applicability of marker-assisted selection (MAS) via Kompetitive Allele-Specific PCR markers in genotypes with high variation in their genetic background. Field trials were conducted across two years and artificially inoculated with local bunt populations. The virulence patterns of these inocula differed between locations and only 15% of the tested genotypes showed stable resistance across test sites. Number and weight of bunt sori relative to the total number and weight of wheat grains in sampled ears revealed that partial infections of ears were frequently appearing. Forty-two breeding lines harboring combinations of four different resistance QTL were developed through MAS. Out of these, a quarter were resistant with a maximum of 5% common bunt incidence. On the other hand, only six out of 46 tested commercial cultivars and breeding lines showed no infection with common bunt, underlining the present scarcity of bunt-resistant cultivars for organic wheat production. By this study we showed that MAS is a useful tool to speed up the selection of resistant lines even in populations with highly diverse genetic backgrounds, and that it is efficient in pyramiding resistance loci and thereby improving the level of resistance

Variability of a Pannonian wheat collection used for organic breeding

Wheat is the most important plant used for human consumption in Europe and represents the crop most widely grown in the organic agriculture. Moreover, wheat also represents the largest range of organic products available on the market. Because of its importance, for the improvement of organic wheat production great efforts and resources are invested. The main goal is to obtain high and stable yields. During the breeding process of wheat (Triticum aestivum L.), when creating a new variety for organic use, it is necessary to incorporate genes responsible for high yield potential and adaptability to different production conditions. In order to determine the variability of grain yield, hectolitre weight, 1000 grain weight and plant height, collection of 30 winter wheat cultivars widely grown in the Pannonian Plain was chosen. The experiment was carried out in a typical Pannonian location at the experimental field of the Institute of Field and Vegetable Crops, Novi Sad, Serbia. The results showed significant variations in the examined traits between the chosen cultivars. Knowledge about the variability between the wheat cultivars could be used for selecting the most suitable ones for breeding in the organic agriculture of the Pannonian Plain

Phenotypic and molecular variability of Serbian and Austrian winter wheat varieties

Genetic variability of locally adapted Serbian and Austrian winter wheat varieties was evaluated in order to assess their potential as a genetic material that can be exploited in crosses between two different European breeding pools. A field trial with 20 elite wheat varieties from each country was set at the Institute of Field and Vegetable Crops, Novi Sad, Serbia in a row-column design with three replications during the 2016/2017 season. The genotypes were phenotyped for tillering, heading and flowering time, plant height, ear length, number of spikelets per spike, number of grains per spike, thousand-kernel weight, chlorophyll content and resistance to prevalent wheat diseases. Additionally, the varieties were genotyped with 30 microsatellites. The varieties from two geographic regions and different release periods were clearly differentiated with population structure obtained from marker data. A significant phenotypic variation was found for most of the traits. Coefficients of variation were the largest for chlorophyll content (16.5%) and plant height (10.1%). Generally, the early genotypes were more susceptible to leaf rust (r = -0.6), while the late maturing genotypes produced more grains per spike (r = 0.4). The Serbian varieties had earlier tillering (p < 0.03), heading (p < 0.00) and flowering (p < 0.00) dates, shorter plant stems (p < 0.00), higher chlorophyll content (p < 0.00) and were more susceptible to leaf rust (p < 0.00) than the Austrian ones. The principal component analysis indicated general properties of the groups that would facilitate the choice of parent combinations for crossings

Evaluation of winter wheat varieties from Central and Eastern Europe for important agronomic traits

Different wheat germplasm exploited in breeding programmes in continental Europe and Pannonian region reflects specific breeding requirements in distinctive environmental conditions. In order to evaluate a potential of locally bred and grown wheat varieties from central Europe, as a source of new genetic variability in a wheat breeding programme in Serbia, 42 elite winter wheat representatives of two different European breeding pools were assessed at the Institute of Field and Vegetable Crops (IFVNC), Novi Sad, Serbia. A field trial with 20 elite wheat varieties was set at the IFVNC in a randomized complete block design with three replications during three seasons (2016/2017, 2017/2018 and 2018/2019). The genotypes were phenotyped for heading and flowering time, plant height, ear length, number of spikelets per spike, number of grains per spike, thousand grain weight, yield, protein content, chlorophyll content index and prevalent wheat diseases. In addition, the varieties were genotyped with microsatellite markers.Book of Abstracts available on the website [http://zpconference75.com

Plant genetic resources and their use in organic agriculture

Organic agriculture and plant genetic resources are closely related topics, as organic farming relies on the conservation and use of diverse and adapted varieties of crops. Plant genetic resources are the raw materials that can help improve the productivity and quality of organic agriculture, as well as enhance its resilience to environmental stresses and pests. Organic agriculture also contributes to the in-situ conservation of plant genetic resources by maintaining and selecting local varieties that have a high degree of genetic variability. An important goal of the ECOBREED project is to identify genetic and phenotypic variations for morphological, abiotic/biotic tolerances/resistance and nutritional quality traits that can be used in organic breeding. The first step to achieve this goal was to make the inventory of available genotypes of four crops: wheat, potato, soybean, and buckwheat. For this purpose, we have examined genetic resources of four crops stored in gene banks, used in previous European and national research projects, and available through plant breeding programmes and seed companies. We have also used agronomic data on available and used varieties in organic farming, varieties characterized by good disease resistance and quality. Selected 200 wheat genotypes originate from 12 different European countries, 197 potato accessions were identified from several databases, the list contains 242 soybean accessions that originated all around the world and of buckwheat were identified through international databases. Much of the material represents cultivars that were released in the last two decades and are included in either the European list or national lists