Sowing Density Research Articles

Productivity of Alternative Barley Genotypes under Variable Intraspecific Competition Resulting from Increasing Sowing Density

Sowing density and row spacing of barley affect the crop efficiency, resource use and final yield, with different genotypes likely to respond differently to this agrotechnical factor. The effect of sowing density on the barley yield, as shaped by structural yield elements such as the number of ears, number of grains per ears and thousand grain weight, depends on the interaction of this factor with the genotype and the growing conditions. Two spring barley genotypes with a black grain color (H. vulgare L. var. nigricans and H. vulgare L. var. rimpaui), differing in ear structure and affiliation to the original wild forms, were studied. Two independent, two-year field experiments were conducted in 2019–2020 and 2021–2022 at two locations with contrasting soil conditions. The effects of genotype and sowing density interactions on the yield, harvest index and structural elements of the yield were assessed. The arley yield was dependent on the interaction of genotype and sowing density but also varied by location. H. v. var. nigricans yielded better at higher densities, while H. v. var. rimpaui showed greater tillering potential at low densities. Environmental factors such as rainfall, temperature and soil composition affected the number of fertile ears, number of grains per ear and thousand grain weight.

Calibration and validation of APISM-Wheat Model in Mediterranean areas

The Agricultural Production Systems sIMulator-Wheat (APSIM-Wheat) model is one of the most widely used agricultural models. It is a powerful simulator that has been successfully calibrated and tested for many locations in the world, especially in Western Australia (WA). However, there is a noticeable lack of a standard guide for realizing the calibration validation of APSIM-Wheat that could be applied in areas with a Mediterranean climate similar to that of WA. Therefore, this study aims to examine crop simulations reported in published articles and to provide a detailed description of input data and statistical assessment, which represent the two main components of the calibration-validation protocols. The PRISMA (PREFERRED Reporting Items for Systematic Reviews and Meta-Analyses) method was used to identify and select relevant papers for this review. Following the analysis of 31 calibration protocols extracted from selected eligible articles, it was found that regardless of the objective of using APSIM-Wheat, the same category of data is required for calibration. As far as meteorological data is concerned, the information essential to this study was daily maximum and minimum air temperatures, rainfall (mm), and solar radiation. In the case of soil data, information about the texture and hydraulic characteristics, especially PAWC, DUL and LL was required. Regarding agricultural management data, this pertains to cultivated crops, Nitrogen fertilization (rate and time of application) and sowing (date and density). For the statistical evaluation, it was observed that 90 percent of studies analyzed in this review revealed the use of RMSE.

Effect of row distance on plant architecture, weed suppression and yield of silage maize (Zea mays L.) and soybean (Glycine max (L.) Merr.) in a pesticide-free cultivation system in Southern Germany

Conventional farming prioritizes monocultures and synthetic chemicals to secure high yields. However, there are a growing number of initiatives worldwide to reduce or eliminate the use of pesticides. One option for pesticide-free weed management is the adjustment of sowing pattern (row distance, plant arrangement, sowing density). This study investigated the effects of an equal distance sowing versus a normal distance sowing (EDS and NDS1) at constant sowing density on plant morphology, growth and yield of silage maize (Zea mays L.) and soybean (Glycine max (L.) Merr.) as well as the weed occurrence. Therefore, a 3-year (2020–2022) pesticide-free, field experiment was conducted at the Heidfeldhof Research Station, University of Hohenheim, Germany. In silage maize, neither plant architecture nor biomass yield showed significant differences between EDS with 0.375 m and NDS with 0.75 m row distance. In contrast, soybean developed a bushier plant architecture with more branches and shorter petioles in EDS with 0.15 m compared to plants in NDS with 0.50 m row distance, demonstrating phenotypic plasticity. A higher number of pods per plant (EDS: 28.05; NDS: 22.73) and seed yield (EDS: 406.58 g m−2; NDS: 389.34 g m−2) indicated the potential for increased yields applying EDS. Crop competitiveness against weeds was higher in EDS than in NDS, especially early in the growing season. The results highlight the importance of EDS as a valuable tool for pesticide-free, non-organic cropping systems through positive effects on crop yield and efficient weed control.

Cereal–Legume Intercropping: Which Partners Are Preferred in Northwestern Europe?

To increase Europe’s self-sufficiency for protein sources, boosting plant protein production is a prerequisite. Yield variability is one of the main problems regarding the cultivation of protein crops. In this light, cereal–legume intercropping can offer a solution, as well-balanced intercropping systems are less prone to yield variations. Therefore, in this study the effects of (i) species/genotype combination, (ii) intercropping sowing densities and (iii) fertilizer regime were evaluated under Belgian (Northwestern European) conditions over three years (i.e., the 2020–2021, 2021–2022 and 2022–2023 seasons). Regarding the species combinations, winter barley x winter pea, winter wheat x winter faba bean and winter triticale x winter faba bean, it was observed that the best-performing combination varied from year to year depending on the prevailing weather conditions. A reduced sowing density (i.e., 130 seeds/m2 for the cereal partner and 20 seeds/m2 in the case of faba bean or 40 seeds/m2 in the case of pea) was sufficient to achieve competitive yields under the prevailing conditions. Inoculation with commercial Rhizobium strains did not result in an increased yield. Fertilization with one or two nitrogen fractions significantly increased the total yield thanks to a yield increase in the cereal partner; however, as a consequence, the proportion of legumes in the mixture decreased. In conclusion, it can be stated that with the investigated cereal–legume combinations, a competitive yield and qualitative protein yield can be achieved with a reduced fertilizer input.

Does the Daily Light Integral Influence the Sowing Density of Tomato Plug Seedlings in a Controlled Environment?

To achieve high-density tomato seedlings in a plant factory with artificial lighting, tomatoes (Solanum lycopersicum Mill. cv. “Zhongza NO.9”) were used as the experimental material. This study expected to analyze the effects of light intensity (150, 200, 250, and 300 μmol·m−2·s−1) and light time (12 and 14 h), as well as daily light integral (DLI, 10.80, 12.60, and 12.96 mol·m−2·d−1) and sowing density (50, 72, and 105 holes per tray), on seedling quality. The results indicated that biomass accumulation, seedling quality, and energy use efficiency of seedlings significantly improved with an increase in DLI. At a DLI of 12.96 mol·m−2·d−1, seedlings sown at a density of 72 holes per tray exhibited comparable growth characteristics and biomass accumulation to those sown at 50 holes per tray. However, under lower DLIs, seedlings at 50 holes per tray displayed superior growth morphology and seedling quality compared to those at 72 holes per tray. This indicates that increasing the DLI can partially mitigate the negative effects of higher sowing density on seedling quality. Light use efficiency (LUE) and energy use efficiency (EUE) were not significantly different between seedlings at 72 and 105 holes per tray but were higher than those at 50 holes per tray. Therefore, optimizing parameters such as DLI and sowing density can effectively enhance the seedling quality, spatial use efficiency, and light use efficiency in industrial seedling production. Based on the results of this study, a DLI of 12.96 mol·m−2·d−1 (achieved with a light intensity of 300 μmol·m−2·s−1 and a light time of 12 h) and sowing density of 72 holes per tray are recommended for cultivating high-quality tomato seedlings while reducing energy consumption.

The Forage Yield and Silage Quality of Maize-Sorghum-Sainfoin Mixtures

The aim of the study was to determine forage yield and silage quality in maize/sorghum (M/S) with sainfoin (SA). The field trial was conducted in 2022 to study the effects of different binary sowing ratios (80%M-20%SA, 60%M-40%SA, 30%M-70%SA; 80%S-20%SA, 60%S-40%SA, 30%S-70%SA, 100%M, 100%SA, 100%S) in 3 replications. Prior to ensiling, the hay yield and fresh yield in the intercropping plots were measured. Parameters of dry matter ratio, pH, crude protein, ADF, NDF, mineral matters, and organic acid were defined in silages opened after fermentation. Before ensiling the highest yield was obtained from maize and yield decreased with an increase in sainfoin sowing density. After ensiling, all of the silage parameters were affected by mixing ratios. When the sainfoin ratio was decreased, dry matter, crude protein, and pH of mixture silages were dramatically reduced, but mineral matters were increased. The highest dry matter was determined in sole sainfoin silage. The best results of lactic acid and acetic acid contents were defined in 80%S-20%SA and 60%S-40%SA silage (except for sole treatments). Besides, it was seen that the addition of sorghum to sainfoin silage increases lactic acid content compared to maize. As a result, intercropping of sainfoin with maize and sorghum provided profitable feed production and improved silage quality. As a result, intercropping of sainfoin with maize and sorghum provided profitable feed production and improved silage quality.

Exploring seed density and limiting similarity to reduce invasive grass performance for grassland restoration purposes

AbstractQuestionsControl of invasive species and seed addition are key steps in grassland restoration. Nevertheless, selecting seed mixes and seed quantities are hard tasks in restoration projects. An interesting idea is to design seed mixes using functional traits and create a community based on limiting similarity to overlap and outcompete the invader. We aimed to test the effect of two sown communities (one created to overlap the invader niche) and three seed sowing densities to reduce the performance of the invasive grass Eragrostis plana.LocationGreenhouse experiment in the Campos Sulinos grasslands region, Southern Brazil.MethodsWe created a bifactorial experiment. The first factor was the sown community, each composed of nine native grasses but with different proportions: (1) Limiting, based on limiting similarity, and (2) Balanced, where all species were sown at the same seed weight. We used leaf functional traits (Specific leaf area, leaf area, leaf dry matter content ) to design the Limiting community. The second factor was the seed density of native species, sowing twice (1) 1 g/m2, (2) 2 g/m2, and (3) 4 g/m2 (i.e., total density was 2, 4, and 8 g/m2). E. plana was sown once at 0.5 g/m2. Above‐ground and below‐ground biomass of all species were collected after nine months to assess the treatment effects.ResultsBiomass production of the invasive species was lower when sown with native species. Nevertheless, both sown communities did not differently affect the invasive biomass production. Higher seed density of native species resulted in lower invasive above‐ground biomass, but not below‐ground biomass. Three native species did not germinate, consequently, the established communities were quite different from those designed.ConclusionsThe low species germination limited our discussion about the use of limiting similarity to design seed mixes. High seed sowing density is a better approach when defining sowing strategies to compete with invasive grasses.

Quality and production potential of green fodder and silage for kharif maize hybrid under rainy season in Punjab

A field study was carried out at Ladhowal Research Farm of ICAR-Indian Institute of Maize Research, Ludhiana, with the objective of finding out the best planting density and sowing date for kharif maize hybrid to maximize green fodder yield and quality silage production. The treatments consisted of two plant densities, i.e., normal density (ND; 60×20 cm) and high density (HD; 60×10 cm), with four dates of sowings in RBD factorial design with three replications. The hybrid PMH 1 sown in mid-July was comparatively superior to other sowing dates at both plant densities. However, yield ND had an edge over HD. Higher biological yield (611.1 q/ha) (p <0.001) and dry matter yield (205.3 q/ha) were reported for ND plots sown in mid-July. The dry matter (DM) content of forage varied (p <0.05) from 32.1 to 35.0%. Crude protein (CP) was high in early sowing and declined to a low level with advanced dates of sowing, whereas ether extract (EE) followed exactly the reverse trend. The dry matter intake and digestible dry matter values were significantly (p <0.001) higher in mid-July sowing. Silages prepared exhibited good ensiling characteristics for all dates of sowing and plant densities. However, mid-July sowing exhibited the lowest values with respect to neutral detergent fiber and acid detergent fiber, with improved nutritive profile, better feeding values, higher in-vitro potential and good fermentation characteristics. Based on this study it was concluded that mid-July sown hybrid PMH 1 had high yield, feed value, NGP as well as NDF digestibility compared to other dates of sowing.

Influence of leaf inclination angle and tillering on population transpiration, soil evaporation, and yield in winter wheat near-isogenic lines.

Leaf inclination angle (LIA) and tillering impact the winter wheat (Triticum aestivum L.) population canopy structure. Understanding their effects on water use (WU) parameters and yield can guide water-saving strategies through population control. In this study, six near-isogenic lines (NILs) and their parents were selected as materials. These special materials were characterized by varying tillering at the current sowing density, a similar genetic background, and, particularly, a gradient in mean flag leaf LIA. The investigation focused on the jointing to early grain-filling stage, the peak water requirement period of wheat crops. Population-scale transpiration (PT) and evaporation from the soil surface (E) were partitioned from total evapotranspiration (ET) by the means of micro-lysimeters. The results showed decreased PT, E, and ET with increased population density (PD) within a narrow density range derived from varying tillering across genotypes. Significant correlations existed between PD and ET, E, and PT, especially in the wettest 2017-2018 growing season. Within such narrow PD range, all the correlations between WU parameters and PD were negative, although some correlations were not statistically significant, thereby suggesting the population structure's predominant impact. No significant correlation existed between LIA and both ET and PT within the LIA range of 35°-65°. However, significant correlations occurred between LIA and E in two growing seasons. Genotypes with similar LIA but different PD produced varied ET; while with similar PD, the four pairs of genotypes with different LIA each consumed similar ET, thus highlighting PD's more crucial role in regulating ET. The yield increased with higher LIA, and showed a significant correlation, emphasizing the LIA's significant effect on yield. However, no correlation was observed with PD, indicating the minor effect of tillering at the current sowing density. Therefore these results might offer valuable insights for breeding water-saving cultivars and optimizing population structures for effective field water conservation.

Multi-trait index: selection and recommendation of superior black bean genotypes as new improved varieties

Common bean provides diet rich in vitamins, fiber, minerals, and protein, which could contribute into food security of needy populations in many countries. Developing genotypes that associate favorable agronomic and grain quality traits in the common bean crop could increase the chances of adopting new cultivars black bean. In this context, the present study aimed at selection of superior black bean lines using multi-variate indexes, Smith-Hazel-index, and genotype by yield*trait biplot analysis. These trials were conducted in Campos dos Goytacazes - RJ, in 2020 and 2021. The experimental design used was randomized blocks, with 28 treatments and three replications. The experimental unit consisted of four rows 4.0 m long, spaced at 0.50 m apart, with a sowing density of 15 seeds per meter. The two central rows were used for the evaluations. The selection of superior genotypes was conducted using the multiple trait stability index (MTSI), multi-trait genotype-ideotype distance index (MGIDI), multi-trait index based on factor analysis and genotype-ideotype distance (FAI-BLUP), Smith-Hazel index, and Genotype by Yield*Trait Biplot (GYT). The multivariate indexes efficiently selected the best black bean genotypes, presenting desirable selection gains for most traits. The use of multivariate indexes and GYT enable the selection of early genotypes with higher grain yields. These lines G9, G13, G17, G23, and G27 were selected based on their performance for multiple traits closest to the ideotype and could be recommended as new varieties.

Optimizing Sowing Density for Parsley, Cilantro, and Sage in Controlled Environment Production: Balancing Productivity and Plant Quality

Sowing density is a key management practice influencing productivity and quality of leafy greens and culinary herbs grown in controlled environments. However, research-based information on optimal density is limited for many culinary herbs. This greenhouse study aimed to quantify sowing density impacts on biomass output, individual plant growth, and morphological traits in hydroponically produced ‘Giant of Italy’ parsley (Petroselinum crispum), ‘Santo’ cilantro (Coriandrum sativum), and sage (Salvia officinalis). Seedlings were grown in phenolic foam cubes with 1, 5, 10, 15, or 20 seeds per cell, transplanted into an ebb-and-flow hydroponic system in a glass-glazed greenhouse with 23 °C target average daily temperature, 16-hour photoperiod, a target daily light integral of 13 mol·m−2·d−1, and harvested at 16 to 28 d after transplanting depending on species. ‘Giant of Italy’ parsley and ‘Santo’ cilantro fresh weight per cell increased quadratically by 274% (57.3 g) and 305% (19 g), respectively, as sowing density increased from 1 to 15 seeds per cell, then plateaued as density further increased. Sage fresh weight plateaued at 10 seeds per cell with an increase of 225% (29.2 g) compared with 1 seed per cell. Cilantro and sage dry weight per cell plateaued at 14 and 8 seeds per cell, respectively, and parsley dry weight quadratically increased as sowing density rose up to 20 seeds per cell. Although fresh and dry weight increased, individual plant height, stem diameter, and individual plant dry weight exhibited linear or quadratic declines as sowing density increased, indicating higher sowing densities restricted individual plant growth. In summary, as sowing density increased, fresh and dry weight per cell generally increased but individual plant quality decreased. For the greatest fresh and dry weight, 20, 18, and 10 seeds per cell should be sown for parsley, cilantro, and sage, respectively. However, to balance fresh weight and crop quality, our results suggest sowing density (seeds per cell) targets of 16 seeds for parsley, 18 seeds for cilantro, and 10 seeds for sage.

Integrating Technology and Agriculture with Advanced Machinery

Abstract: Agricultural technologies are rapidly evolving towards a new paradigm – Integrating Technology. Within this paradigm, digitalization, automation and artificial intelligence play a major role in crop production, including weeding and pest control. This evolution presents both challenges and opportunities, such as leapfrogging from manual and animal-driven technologies to automated and mechanized equipment in developing countries and closing the digital divide. Traditional agricultural mechanization, characterized by the use of tractors and engine power, will be matched and even surpassed by automated equipment and robotics and the precision they can provide in farm operations. Conservation agriculture (CA) is an approach that involves crop diversification, permanent soil cover and minimal soil disturbance (e.g. limited tillage). CA increases soil structure and soil organic matter, promotes rich microbial diversity, retains water and nutrients, and better manages pests and diseases, making agricultural soils more productive and resilient to changes in climate. However, it requires specialized equipment – for example, for direct drilling of crop seed into the soil at the right depth and sowing density. Agricultural robotics can support these environmentally sustainable practices, by allowing spot weeding and precision management of nutrients, pests, diseases and weeds through mechanical removal or spot application of chemicals. Agricultural robots will also be able to substitute arduous labour, especially when there is limited availability, thus increasing social sustainability. The development of Integrating Technology will create new opportunities that can attract youth and entrepreneurs into the sector, tackling some of the causes for rural–urban migration and contributing to the economic component of sustainability.

Root growth and belowground interactions in spring wheat /faba bean intercrops

Abstract Background and aims Intercrops offer multiple advantages over sole crops. The aim of our study was to characterize root growth and interactions in spring wheat/faba bean intercrops to better understand belowground interactions that govern resource capture. Materials and methods A field experiment was conducted with one faba bean cultivar and two spring wheat cultivars sown at three sowing densities, defining three intercropping designs. Destructive root coring was conducted (0–100 cm) in the intercrops and sole crops at two development stages. FTIR spectroscopy was used to discriminate the species’ root masses. The plant-plant interaction index was calculated to represent the belowground interactions. Results A negative impact of intercropping on total root mass was observed in the treatment with high sowing density in both stages. For the fully and partial replacement design treatments, plant-plant facilitation was more pronounced than competition in all layers. Competition dominated root growth in the treatment with high sowing density in both stages. Lower sowing densities encouraged deep root growth of wheat (both cultivars) in intercropping. The early root growth in depth and in density of one spring wheat cultivar impacted negatively faba bean root growth. Intercropping resulted in a grain yield advantage in both fully and only one partial replacement design treatment. Conclusion In the intercrops, total root mass and plant-plant interactions were affected more by sowing density than by the spring wheat cultivar. Understanding the effect of sowing density on root growth in intercropping can help to support the design of sustainable intercropping systems.

The genotypic variation in the positive response of sorghum to higher sowing density is linked to an increase in water use efficiency

In semi-arid tropical areas, sorghum is sown at very low planting densities. Hence, increasing plant density represents an opportunity to improve productivity. However, assessing the expected increase in water needs is critical prior to testing higher densities under rainfed conditions. This was tested with a panel of elite cultivars in field and lysimiter experiments, and testing the effects of two density treatment, high (HD, 22 plants.m-²) and low (LD, 11 plants.m-²), on grain and biomass yield and on water use and water use efficiency (WUE). Doubling the conventional sowing density significantly increased biomass and grain yield, with a genotypic variability in the biomass response. No link was found between the response to density and the maintenance of the tillering capacity, whereas the response to density was somewhat explained by a differential increase in the leaf area index under high density (r=0.43 P<0.05). Lysimeter experiments showed that, compared with the conventional density, the high-density treatment had 62% increase in biomass vs a 38% increase in water use, resulting in a 17% higher WUE on average of the genotypes tested. There was an appreciable genotypic variability in this degree of WUE increase under high density. The most striking result was the very tight positive link between the biomass response to density and the differential increase in WUE in the dry season (r=0.91 P<0.0001), whereas in the wet season this link was negative (r=-0.48 P<0.02). This work shows that intensifying sorghum production by increasing sowing density is possible, in the short term using cultivars that show the largest WUE increase under high density, in the longer term by breeding high-density adapted cultivars, targeting plant traits that explain the tight link between higher WUE and higher yield under high density.

The effects of native seed mix composition and sowing density on plant community reassembly in wetlands

AbstractSeed‐based restoration of wetlands is often necessary to improve important ecosystem functions (e.g., invasion resistance and habitat provisioning) and meet society's need for wetland ecosystem services such as supporting recreational activities and improving water quality. However, persistent questions remain about the composition and sowing density of seed mixes needed to restore robust native wetland plant communities. In Great Salt Lake wetlands (Utah, USA), the revegetation of native species is crucial to recovering critical habitat and preventing reinvasion of the invasive, non‐native grass Phragmites australis and other invasive species (e.g., Typha spp.). In greenhouse and field experiments, we investigated the effects of seed mix composition and sowing density on plant community reassembly. We predicted that seed mixes containing native forb species with resource‐preempting traits (e.g., rapid seedling emergence and high aboveground growth rate) and high sowing densities (&gt;5500 pure live seed m−2), would increase native plant light acquisition and establishment, thereby limiting invasive species. To our surprise, the effect of seed mix composition on native plant performance (cover and biomass) varied among the experiments, with distinct differences between plant functional groups arising. Native forb species had the highest performance in the greenhouse, but native grasses performed better in the field. Although multiple seed mix compositions show promise for establishing high native cover and biomass, these mixes may not always suppress invasive species. Interestingly, seed mix composition most often affected plant performance independent of sowing density. However, in one greenhouse experiment, we found that only slow‐growing mixes required a high sowing density to maximize native cover, an indication that the ideal sowing density may depend on the seed mix composition. Our research also supports the idea that in addition to reducing propagules of invasive species via appropriate management strategies, the application of higher sowing densities (&gt;5500 pure live seed m−2) may lead to more favorable outcomes when a high density of invasive plant seeds remains or stressful field conditions are present. This research contributes to knowledge of plant community reestablishment in wetlands and demonstrates how seed‐based restoration strategies can catalyze native species revegetation and, in some situations, reduce the cover of invasive species.

Morphogenic characteristics of black oat and vetch under different densities

The objective of this study was to assess the morphogenic characteristics Avena strigosa and Vicia sativa plants cultivated in different sowing densities. The experiment was conducted in vases with farming soil. The experimental design involved randomized units, with four repetitions, consisting of a single vetch plant placed in the centre of each experimental unit and a variable number of oat plants (0, 1, 2, 3, 4, and 5) planted around the borders. The same procedure was also conducted with a single oat plant placed in the centre of the vase and a variable number of vetch plants (0, 1, 2, 3, 4, and 5) planted around the borders. The plants were grown for a total of 35 days. Morphogenic characteristics of the central plant were assessed at the time of transplantation as well as every 7 days. It was observed that the density increase in vetch plants did not significantly influence stem elongation, plant elongation, and leaf senescence rates of oat plants. However, higher densities did reduce the tiller appearance rate in oat plants. Increases in oat density caused significant impacts on the elongation rate and linear growth in the leaf senescence rate and reduced the number of ramifications in vetch plants. Higher density caused reduced leaf appearance and tiller rates while increasing phyllochron values. The results of this study indicate that increases in plant density trigger competition responses in both oat and vetch, which in turn negatively affect many of the assessed morphogenic characteristics for both species.

The Quality of Winter Wheat Grain by Different Sowing Strategies and Nitrogen Fertilizer Rates: A Case Study in Northeastern Poland

The present study was undertaken to determine the effect of different sowing strategies and spring nitrogen (N) fertilizer rates on the technological quality of winter wheat (Triticum aestivum L.) grain in terms of its milling quality, protein complex quality, and enzyme activity (falling number). Winter wheat grain for laboratory analyses was produced in a small-area field experiment conducted between 2018 and 2021 in the AES in Bałcyny (53°35′46.4″ N, 19°51′19.5″ E, NE Poland). The experimental variables were (i) sowing date (early: 6 September 2018, 5 September 2019, and 3 September 2020; delayed by 14 days: 17–20 September; and delayed by 28 days: 1–4 October), (ii) sowing density (200, 300, and 400 live grains m−2), and (iii) split application of N fertilizer in spring (40 + 100, 70 + 70, and 100 + 40 kg ha−1) at BBCH stages 22–25 and 30–31, respectively. A sowing delay of 14 and 28 days increased the bulk density (by 1 and 1.5 percent points (%p), respectively), vitreousness (by 3 and 6%p, respectively), and total protein content of grain (by 1% an 2%, respectively). A sowing delay of 14 days increased grain hardness (by 5%), the flour extraction rate (by 1.4%p), and the falling number (by 3%) while also decreasing grain uniformity (by 1.9%p). In turn, a sowing delay of 28 days increased the wet gluten content of grain (+0.5–0.6%p) and improved the quality of the protein complex in the Zeleny sedimentation test (+1.5%). An increase in sowing density from 200 to 300 live grains m−2 led to a decrease in grain uniformity (by 2.6%p), the total protein content (by 1.5%), and the wet gluten content of grain (by 0.7%p). A further increase in sowing density decreased grain vitreousness (by 1.4%p). The grain of winter wheat fertilized with 40 and 100 kg N ha−1 in BBCH stages 22–25 and 30–31, respectively, was characterized by the highest hardness (64.7), vitreousness (93%), flour extraction rate (73.9%), total protein content (134 g kg−1 DM), wet gluten content (36%), and Zeleny sedimentation index (69 mL).

Effect of sowing density on performance and biometric features of pedunculate oak

Sowing density is one of the most important factors influencing seedling quality. In forest nurseries, to ensure full seeding, it is recommended to obtain approximately 200 seedlings from 1 m2 (ZHL 2012). The aim of the study was to assess the effect of sowing density on sowing efficiency and the morphological features of pedunculate oak seedlings. Acorns were sown directly by broadcast seeding on 20 test plots, each 4 m in length, in four replications. The following variants were used:- 250acorns capable of germination totaling 341 acorns per 1 linear meter (0.9 m2);- 300 acorns capable of germination totaling 410 acorns per 1 linear meter (0.9 m2);- 350 acorns capable of germination totaling 478 acorns per 1 linear meter (0.9 m2);- 400 acorns capable of germination totaling 546 acorns per 1 linear meter (0.9 m2);- 450 acorns capable of germination totaling 614 acorns per 1 linear meter (0.9 m2). At the end of the growing season, seedlings were counted per 1 m (0.9 m2) in the central part of each plot. Sowing efficiency was determined as a percentage of seedling yield from the sown seeds. For laboratory analysis, 30 seedlings from each plot (600 in total) were collected. Based on biometric features like shoot height, root collar diameter, and dry weights of shoots, roots, and leaves, quality indicators such as the sturdiness quotient (SQ) and the Dickson quality index (DQI) were calculated. Sowing efficiency at the end of the vegetation season ranged between 39.68% and 50.12% and was not statistically significant. The research revealed that sowing density influenced seedling biometric characteristics. Pearson’s correlation coefficients showed significant negative correlations between the number of seedlings obtained in an experimental plot and the dry weight of the root, number and dry mass of leaves, as well as the DQI. The seedlings from all sowing variants complied with the binding Polish standard, outlined in the Regulation of the Minister for the Environment of 18 February 2004 (Ministerstwo Środowiska 2004) by over 96%. Keywords: seeding density, sowing rate, seedling quality, sowing performance, sturdiness quotient (SQ), Dickson quality index (DQI), Quercus robur L.

Optimising Sowing Density for Microgreens Production in Rapini, Kale and Cress

Microgreens represent a valuable agrifoods niche. Their cropping cycle is shorter than that of baby leaf greens, but the sowing density is typically much higher, and this has important cost implications for the grower. The current research demonstrates that the choice of sowing density strongly influences yield, as well as developmental stage and other quality parameters. Results also depended on the choice of the species and landrace. Considering the cost of seed, the option of accessing locally available landraces becomes particularly intriguing, again with relevant implications in choosing seed density. Rapini (landraces Cima grande and Fasanese), kale (landraces Barese and Altamura), and commercial cress were grown in an indoor environment. The effects of the three sowing densities (from 3 to 5 seeds∙cm−2) and the growing cycle (earlier harvest, 11 days from sowing, or later harvest, 14 days from sowing) on the microgreen yield and quality were studied. Sowing density affected yield (+19% at highest vs. lowest density), dry matter (but only with a longer cycle, and variable by landrace, with Fasanese rapini landrace 7% more than the Cima grande landrace), developmental stage, and soil coverage. The effects of sowing density can be modulated by cycle duration. Crop heights were 25% and 44% greater for the longer cycle of the Cima grande and Fasanese rapini landraces, respectively. In conclusion, the choices of the species/landrace and seed density must be carefully evaluated given costs and outcomes, with potential for the production of different final products (e.g., microgreens at earlier or later stages, other characteristics) and also for control over costs.

Effect of planting density on yield and architecture suitability of groundnut (Arachis hypogaea) varieties

A field experiment was conducted during rainy (kharif) seasons of 2018 and 2019 at the research farm of Sri Venkateswara Agricultural College (Acharya N. G. Ranga Agricultural University), Tirupati, Andhra Pradesh, to study the effect of planting density on yield and architecture suitability of groundnut (Arachis hypogaea L.) varieties. The experiment included 4 sowing densities (D1, 33.3 plants/m2; D2, 50 plants/m2; D3, 66.6 plants/m2 and D4, 100 plants/m2) and 3 genotypes with varying architecture (G1, Kadiri 6-erect; G2, Kadiri 9-decumbent 2; and G3, Dharani-decumbent 3). The results showed that across planting densities, Dharani and Kadiri 9 genotypes showed higher architectural traits, structural carbohydrates and kernel yield compared to the Kadiri 6. A significant positive correlation was detected between the lodging percentage and both plant height (r = 0.88**) and internodal length (r = 0.61*). Significant negative correlations, were identified between lodging percentage and several parameters, including leaf thickness (r = -0.92**), specific leaf weight (r = -0.93**), stem diameter (r = -0.79**), specific stem weight (r = -0.97**), number of branches (r = -0.72**), cellulose content (r = -0.80**), and lignin content (r = -0.79**). These findings indicate that the decumbent architecture is optimal for achieving groundnut lodging resistance and kernel yield in high-density planting systems.