Alfalfa is the main perennial legume and a rich source of phytoestrogens. Variation of phytoestrogen content and agronomic traits was evaluated in twenty alfalfa populations over two consecutive years. The most dominant phytoestrogen in alfalfa populations was genistein, while slightly lower levels were found for kaempferol and coumestrol. Several populations (Af 1, 12, 18, 19, 20) showed superior agronomic performance, especially high forage yield (up to 71.93 t ha−1). These populations were also characterized by a lower (Af 1, 12, 18, 20) or high (Af 1, 19) content of total and individual phytoestrogens, including Af 8 population with the highest total content (2637.10 μg g-1 of DM) and content of most of the individual phytoestrogens and favorable agronomic properties. Ward hierarchical clustering method grouped the twenty evaluated populations into four distinct clusters. Identified materials provide a valuable source of germplasm for further breeding programs in order to develop new high-yielding cultivars with either low (for forage use) or high (for possible pharmaceuticals/nutraceuticals industries) phytoestrogen content.
Alfalfa is the most important forage legume in the production of voluminous fodder. Although not primarily produced for its seeds, the seed yield is still important for the recognition and commercial viability of the cultivars on the market. Creating a cultivar of superior yield and forage quality with satisfactory seed production is one of the biggest challenges for alfalfa breeders and seed producers. The objective of this study was to determine forage and seed yields of 19 newly developed alfalfa experimental populations (ABP 1–19) of the Agricultural Institute Osijek during a long-term research period (2014–2018) in different climatic conditions. Significant differences were found between ABPs and years for forage and seed yields. Three-year (2014–2016) average green mass yield ranged from 68.41 t ha–1 (ABP 6) to 78.05 t ha–1 (ABP 19) and dry matter yield from 13.73 t ha–1 (ABP 6) to 15.30 t ha–1 (ABP 18). The average two-year (2017–2018) seed yield varied from 150.78 kg ha−1 (ABP 9) to 335.35 kg ha−1 (ABP 7). Annual forage yield significantly increased from the year of establishment to the second and third growing seasons of alfalfa. The highest average annual yield of green mass (90.24 t ha−1) was achieved in 2015, dry matter yield (17.62 t ha−1) in 2016 and the seed yield (394.17 kg ha−1) in 2017. During the researched period there was a considerable decreasing trend in forage yield from the first to the last cut, except in the year of the alfalfa establishment. Several alfalfa populations (ABP 19, 8, 14) superior in all analyzed traits were identified, and they represent top performing materials with the potential for developing and releasing cultivars in the near future. Populations with high yields of green mass and dry matter (ABP 12, 18, 1) and seed yield (ABP 7, 4) were also detected and represent valuable genetic material to improve our alfalfa breeding program.
Watermark, Tensiometer and Time Domain Reflectometry (TDR) are commonly used soil water sensors in irrigation practice whose performance depends on soil type, depth and growing conditions. Here, the results of sensor performance evaluation in different soil depths as well as the field and laboratory testing in silty clay loamy soil are presented. Gravimetric soil moisture samples were taken from sensor installation depths (10, 20, 30 and 45 cm) and used as reference Soil Water Content (SWC). The measurements varied significantly (p < 0.05) across the monitoring depths. On average across the soil depths, there was a strong negative linear relationship between Watermark (r = −0.91) and TDR (r = 0.94), and a moderate negative (r = −0.75) linear relationship between SWC and Tensiometer. In general, Watermark and Tensiometer measured SWC with great accuracy in the range of readily available water, generated larger Mean Difference (MD) than TDR and overestimated SWC, while TDR underestimated SWC. Overall, laboratory testing reduced the root mean square error (RMSE, Watermark = 1.2, Tensiometer = 2.6, TDR = 1.9) and Mean Average Error (MAE, Watermark = 0.9, Tensiometer = 2.04. TDR = 1.04) for all tested sensors.
The spring field pea is one of the most important coarse legumes. This study was carried out to investigate the response of a spring field pea variety to three plant densities (50, 100, and 150 plant m-2) during the 2017 and 2019 growing seasons in eastern Croatia. The field study was set up as a Randomized Complete Block Design (RCBD) in four replications. The results have demonstrated a significant effect of the plant densities and the growing seasons on the seed yield and on the following yield components: plant height and the number of pods/plant. The effect of plant densities on the number of seeds/pod and the thousand-seed weight was not significant. As for a growing season, the highest seed yield, plant height, the number of pods/plant were obtained in the second growing season. Furthermore, a maximum seed yield was recorded at the 150-plant m-2 plant density. This study has demonstrated that planting the spring field pea at different plant densities significantly modifies the spring field pea yield, plant height and number of pods/plant.
Climate change and the variable extreme weather conditions that today’s agricultural producers are dealing with represent some of the most important issues in food production. Nowadays, weather patterns are increasingly unpredictable, characterized by frequent fluctuations in temperature, precipitation, and extreme weather events. As a result, there is an increasing demand for scientists to develop more resilient and tolerant crop cultivars. Plant breeders must become creative and utilize all available resources to create modern high-yielding and widely adapted cultivars to help agriculture grow and thrive amidst the emerging changes. Forage legumes, due to their beneficial characteristics, are among the crops that can contribute to mitigating the consequences of climate change. Furthermore, what certainly does not contribute to weather conditions is the erosion of plant genetic material, which has been caused by the modernization of agriculture and the selection of the best cultivars with desirable traits over many years. Crop wild relatives (CWRs) and landraces represent plant genetic materials rich in novel gene variants that contain traits for resistance and tolerance to different climatic conditions. To expand the genetic base of cultivars and mitigate the consequences of climate change, breeders are increasingly utilizing pre-breeding methods. These methods include all the activities connected to the identification of desirable genes and traits from un-adapted materials, such as CWRs, and the transformation of these traits to an intermediate set of materials that can be used for creating new cultivars. This review paper will cover the pre-breeding process, including its components, and the resistance and/or tolerance of the CWRs and landraces of forage legumes to different extreme environmental conditions.