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To target the lack of suitable grass species in the ecological restoration process of the Muli mining area, nine ecological grass species of Gramineae, Gentianaceae, Scrophulariaceae, and Ranunculaceae were selected as experimental materials to simulate the external alkaline environment for a seed germination test, which could be used to explore the response of seed germination to the environment. At the same time, Poa pratensis L. 'Qinghai', Deschampsia cespitosa, Koeleria cristata, and Elymus tangutorum were used as test materials to carry out a variety of comparison and screening tests of suitable seeding rates. The effects of the seeding rate on plant coverage, biomass, forage nutrients, and soil properties were analyzed by a variety of comparison and seeding rate tests. The results showed the following: (1) The relative germination rate of Koeleria cristata, Elymus tangutorum, Deschampsia cespitosa, and Poa pratensis L. 'Qinghai' was more than 70%, and the coverage in the returning green period was more than 60%, which was significantly higher than that of other treatments (p < 0.05) and can better adapt to the environment of the Muli mining area compared to other grass species. Meanwhile, the adaptability of Pedicularis kansuensis, Gentiana macrophylla, and Aconitum pendulum was weak. (2) It was found that when the seeding rate was 9 g·m−2, the biomass of Poa pratensis L. 'Qinghai', Deschampsia cespitos, and Koeleria cristata was the highest, which was 296.45 g·m−2, 224.32 g·m−2, and 236.35 g·m−2, which was significantly higher than that of other treatments (p < 0.05); the aboveground biomass was 356.24 g·m−2 when the seeding rate of Elymus tangutorum was 18 g·m−2, which was significantly higher than that of other treatments (p < 0.05). The membership function showed that the comprehensive evaluation value was 0.701, 0.576, 0.610, and 0.673 when the seeding rate of Poa pratensis L. 'Qinghai', Deschampsia cespitos, and Koeleria cristata was 9 g·m−2 and the seeding rate of Elymus tangutorum was 18 g·m−2. To sum up, it is recommended that the four ecological grass species of Poa pratensis L. 'Qinghai', Deschampsia cespitosa, Koeleria cristata, and Elymus tangutorum can be used as the main grass species for ecological restoration in high-altitude and alpine areas such as the Muli mining area, which is affected by an alpine climate and fragile habitats. The optimum sowing rate of Poa pratensis L. 'Qinghai', Deschampsia cespitosa, and Koeleria cristata is 9 g·m−2, and that of Elymus tangutorum is 18 g·m−2. This cultivation method can effectively promote plant growth and development, improve the physicochemical properties of soil, and is conducive to improving the stability and sustainability of artificial grassland in alpine mining areas. [ABSTRACT FROM AUTHOR]

Increasing the diversity of native forbs in pasturelands can benefit insect pollinator populations, which have been declining widely. Establishing native forbs into existing pasturelands can be challenging, however, and information about effective planting strategies in these systems is lacking. In this study, we evaluated several planting strategies to improve native forb establishment. Two field experiments were conducted in Virginia, USA in 2021 and 2022. Experiment 1 evaluated how six herbicide treatments and tillage affected establishment success when forbs were planted in summer or fall. Experiment 2 investigated how different seeding rates from 2.2 to 56 kg/ha and pre-seeding cold stratification affected forb establishment. In experiment 1, treatments using Roundup/glyphosate and tillage resulted in the most forb establishment. Planting in summer improved establishment with Roundup/glyphosate application. In experiment 2, native forb plant establishment was positively associated with seeding rate (p < 0.001), with a rate of 56 kg/ha resulting in almost 3x more forbs compared to the lowest seeding rate. Cold stratification also increased target plant establishment (p < 0.01), but these effects were inconsistent among species. Our results suggest that effective native forb establishment can be achieved through intensive site preparation with Roundup/glyphosate or tillage to suppress vegetation and planting at rates no higher than 11 kg/ha. [ABSTRACT FROM AUTHOR]

The dynamics of the productivity of the sunflower hybrid "Baiterek 17" were studied for rainfed conditions of the steppe and dry steppe zones of Kazakhstan for two fertilizer levels (without fertilizers and with the application of a nitrogen-phosphorous fertilizer), two sowing dates, and three seeding rates. The growing season duration varied among zones and was affected by sowing dates. An increase in duration (3–5 days) was observed for the early sowing date and fertilized treatments, regardless of the zone. Increasing the seeding rate for all treatments by sowing date and fertilizer application reduced the duration of the growing season by 3–6 days. The fertilizer application did not affect the formation of seedlings in the study areas. In the dry steppe zone, from 2.5 to 4.8 plants/m2 were formed before harvesting, with an increase in the number of plants at the high seeding rate (57,000 seeds/ha). In the steppe zone, the same pattern was preserved: from 3.5 to 4.9 plants/m2 at a seeding rate of 65 thousand seeds/ha. The maximum diameter and weight of the flower head were found for the early sowing date and fertilized treatments at a low seeding rate, with a strong effect on the yield for both the steppe and dry steppe zones in 2022. On average, for both years, the highest yield for the dry steppe zone was obtained for the sowing date of 15 May and at a seeding rate of 57,000 seeds/ha, while for the steppe zone, the highest yield was obtained for the 10 May planting date and at a sowing rate of 65,000 seeds/ha. Improving plant nutrition and increasing the plant density up to a seeding rate of 65,000 seeds/ha for the early sowing dates (10 May) increased the plasticity in the steppe zone. For the dry steppe zone, the plasticity of the hybrid decreased, but the highest plasticity was also obtained for an earlier sowing date (15 May) and at a seeding rate of 57,000 seeds/ha crop. The study shows that the hybrid "Baiterek 17" has a high ecological plasticity under changing environmental conditions and, with an increase in moisture availability, it requires intensive agricultural practices (fertilization, increased seeding rate, and early sowing dates) to obtain a high yield. [ABSTRACT FROM AUTHOR]

In this study, we developed a monitoring system to accurately track the seeding rate and to identify the locations where the mechanical pot-seeding machine failed to sow seeds correctly. The monitoring system employs diverse image processing techniques, including the Hough transform, hue–saturation–value color space conversion, image morphology techniques, and Gaussian blur, to accurately pinpoint the seeding rate and the locations where seeds are missing. To determine the optimal operating conditions for the seeding rate monitoring system, a factorial experiment was conducted by varying the brightness and saturation values of the image data. When the derived optimal operating conditions were applied, the system consistently achieved a 100% seed recognition rate across various seeding conditions. The monitoring system developed in this study has the potential to significantly reduce the labor required for supplementary planting by enabling the real-time identification of locations where seeds were not sown during pot-seeding operations. [ABSTRACT FROM AUTHOR]

Three soybean field trials were conducted in Indiana to evaluate the integration of seed treatment, cultivar selection, and seeding rate on sudden death syndrome (SDS) root rot, pathogen load in the root, foliar symptoms, yield, and net return. Two soybean cultivars, one moderately resistant and one susceptible to SDS, were planted at three seeding rates (272,277 seeds/ha, 346,535 seeds/ha, and 420,792 seeds/ha). Fluopyram and pydiflumetofen seed treatments were applied to both cultivars, and the cultivars were then compared with a control. Low foliar SDS disease pressure was observed in our study. Seed treatment with either fluopyram or pydiflumetofen and the use of a moderately resistant cultivar decreased Fusarium virguliforme DNA concentration in the root relative to the control and the use of a susceptible cultivar. Fluopyram significantly reduced visual root rot severity by 8.8% and increased yield by 105 kg/ha relative to the control but was not different from pydiflumetofen. However, pydiflumetofen performed the same as the control with respect to root rot severity and yield. Findings from this study support the use of a seed treatment to protect roots from infection and the use of a moderately resistant cultivar planted at a seeding rate of 346,535 seeds/ha to protect yield and maximize net returns when a field has low foliar SDS pressure. [ABSTRACT FROM AUTHOR]

Dryland winter wheat (Triticum aestivum L.) production plays an extremely important role in the southeast of the Loess Plateau. Planting patterns have great influence on improving soil water storage and yield, and should be matched with different seeding rates. In order to assess the effect of different sowing methods on the drought resistance and stable yield of dryland wheat, a field experiment was conducted in Wenxi County Dryland Wheat Experimental Base in Shanxi Province, China. In the current study, the effects of three planting techniques (drilling sowing, furrow sowing, and film-mulched sowing) and four seeding rates (150, 225, 300, and 375 kg ha−1) were examined on water storage, dry matter formation, yield, and water use efficiency (WUE). The results showed that furrow sowing (FS) and film-mulched sowing (FM) treatments increased soil water storage in the 0–300 cm soil layer at overwintering and jointing stages. In addition, FS and FM increased soil water consumption in the 0–300 cm soil layer from overwintering to maturity of wheat. Furthermore, FS and FM significantly increased the dry matter accumulation from the overwintering to the mature stage, promoted its accumulation in vegetative organs and translocation to grains after anthesis, viz., increased yield by 6.2% and 7.9%, and WUE by 4.6% and 5.3%, respectively, as compared with those of the drilling sowing (DS) treatments. Pearson's correlation analysis showed that grain yield had a significantly positive correlation with soil water storage at overwintering and jointing. Moreover, grain yield was significantly positively correlated with soil water consumption in the 0–300 cm soil layer from jointing to maturity. Additionally, the seeding rate of 150 kg ha−1 with FS could obtain higher WUE and grain yield. Therefore, it is strongly recommended that the seeding rate of 150 kg ha−1 is used with FS to improve the grain yield and WUE of dryland agricultural systems in China. [ABSTRACT FROM AUTHOR]

There is growing interest in malting barley (Hordeum vulgare L.) production in the Northeastern United States. This crop must meet high quality standards for malting but can command a high price if these quality thresholds are met. A two-year field experiment was conducted from 2015 to 2017 to evaluate the impact of two leguminous cover crops, sunn hemp (Crotalaria juncea L.) and crimson clover (Trifolium incarnatum L.), on subsequent winter malting barley production. Four cover crop treatments—sunn hemp (SH), crimson clover (CC), sunn hemp and crimson clover mixture (SH + CC), and no cover crop (NC)—were grown before planting barley at three seeding rates (300, 350, and 400 seeds m−2). SH and SH + CC produced significantly more biomass and residual nitrogen than the CC and NC treatments. Higher barley seeding rates led to higher seedling density and winter survival. However, the subsequent spring and summer barley growth metrics, yield, and malting quality were not different in any of the treatments. There is much left to investigate in determining the best malting barley production practices in the Northeastern United States, but these results show that winter malting barley can be successfully integrated into crop rotations with leguminous plants without negative impacts on barley growth, yield, and grain quality. [ABSTRACT FROM AUTHOR]

The effects of drill and broadcast planting methods on cover crop biomass production depend on various environmental and operational factors. We investigated whether drilling and broadcasting result in different amounts of biomass production by crimson clover (Trifolium incarnatum L.) and hairy vetch (Vicia villosa Roth) in the upstate of South Carolina, and results vary when seeding rates are increased by 50% from the standard value (22.4 kg ha−1). Field trials were conducted during the fall–winter of 2019–2020 (season one) and 2020–2021 (season two) at the Piedmont Research and Education Center in Pendleton, SC, USA. Cover crop (hairy vetch, crimson clover), planting method (broadcast, drill), and seeding rate (standard, high) treatments were arranged as a 2 × 2 × 2 factorial in both years. Aboveground biomass was measured after 22.5 weeks from planting. At standard seeding rates, crimson clover produced a higher biomass when drilled, rather than broadcasted, whereas biomass production did not vary for hairy vetch. Even with 50% higher seeding rates, broadcasting did not always produce the same biomass as that of drilling for crimson clover. Our results suggest that the advantage of drilling over broadcasting depends upon the cover crop species, as crimson clover responds well to drilling, whereas hairy vetch does not. [ABSTRACT FROM AUTHOR]

Dose-response experiments for confirmation of herbicide-resistant weeds are almost always conducted using weed monocultures, thereby ignoring the interaction of interspecific plant interference with herbicide efficacy. Controlled-environment dose-response bioassays were conducted using three kochia [Bassia scoparia (L.) A.J. Scott] populations with four spring wheat (Triticum aestivum L.) densities (0, 200, 400, and 600 plants m−2) to determine how increasing intensity of interspecific plant interference altered the fluroxypyr dose-response relationship of resistant and susceptible kochia. The resistant population exhibited 10.8-, 15.0-, 7.0-, and 8.1-fold resistance to fluroxypyr in the absence of crop interference based on plant survival, biomass fresh weight, and visible control at two and four weeks after application, respectively. Increased wheat densities suppressed fluroxypyr-resistant kochia the greatest, resulting in a linear reduction in the fluroxypyr rate causing 50% plant mortality (LD50) and visible control (ED50) for the resistant but not the susceptible populations. This reduced the expression of fluroxypyr resistance based on kochia plant survival (from 10.8- to 4.3-fold resistance) and visible control (from 8.1- to 4.6-fold resistance) as wheat density increased from 0 to 600 plants m−2. Therefore, enhanced interspecific plant interference caused by increased wheat densities altered but did not repress the expression of fluroxypyr resistance in kochia. [ABSTRACT FROM AUTHOR]

Over two cropping seasons, 2017/18 and 2018/19, an experimental trial was conducted in a typical cereal-growing environment of the Calabrian hills (southern Italy) to study seeding rate (D) and nitrogen fertilization (N) effects on two barley F1 hybrids (Zoo and Jallon) compared to those of a traditional variety (Lutece), assessing the bio-agronomic response. Barley hybrids, gradually introduced into the principal European countries starting in 2010 as winter forage, currently represent a significant part of the EU internal market. Productive performance was evaluated as grain yield for feed and total biomass for silage and/or biogas production. Research results pointed out the greater performance of barley hybrids compared to conventional varieties in terms of both grain and biomass production. On average, barley hybrids vigour mainly manifested itself through a high tillering and a greater number of ears m−2 compared to those of the conventional variety (+24 and +23%, respectively). Furthermore, barley hybrids were characterized by a greater 1000-kernel weight and hectolitre weight than those of the Lutece variety (conventional variety). A significant increase in grain production was observed, increasing density from D150 to D225 rates (+35% and +33%, respectively) which was followed by a decrease in production shifting from D225 to D300 doses. A significant increase in biomass production was as well highlighted for the two hybrids, shifting from D150 to D225 rates (+26% and +27%, respectively). The applied nitrogen dose highlighted a different behaviour between the hybrids and the conventional variety; in particular, the lowest nitrogen dose (N80) negatively influenced the Lutece variety both in terms of grain and biomass production (−9% and −16%, respectively) while the hybrids showed the best agronomic response even at the lowest dose. On average, with the N80 dose, grain yield of Zoo and Jallon was greater than 20% and 16%, while with the N120 dose grain yield was 9% and 7%, respectively. A similar behaviour was found for biomass yield. It should therefore be emphasized that barley hybrids possess high yielding capacities and that such higher grain production can be achieved in a Mediterranean environment by using a lower seed rate (approximately −25%) and a reduced nitrogen dose (approximately −33%) compared with those commonly applied to conventional varieties. [ABSTRACT FROM AUTHOR]

In order to obtain desirable crop yields, grain seeds need to be sown at the optimal seed amount per hectare with uniform distribution in the field. In previous grain sowing processes, the seeding rates are controlled by the rotational speed of the flute roller which significantly effects the uniform distribution of the seeds due to disturbances, such as the reduction of the seeds' mass in the hopper and the change of working length of the flute roller. In order to overcome the above problem, we developed an adaptive roller speed control system based on the seed flow rate sensor. The developed system can monitor and feedback actual seeding rates. In addition, based on the monitoring value of the real-time seeding rates, an adaptive roller speed control method (ARSCM), which contains an algorithm for calculating the seeding rate with a compensation, was proposed. Besides, the seeding performance of the ARSCM and that of the conventional roller speed control method (CRSCM) were compared. The results of constant-velocity experiments demonstrated that the accuracy (SA) and the coefficient of variation (SCV) of the seeding rates controlled by the ARSCM were 94.12% and 6.77%, respectively. As for the CRSCM, the SA and SCV were 89.00% and 8.95%, respectively. Under variable-velocity conditions, the SA and SCV of the proposed system were 91.58% and 11.08%, respectively, while those of the CRSCM were 88.48% and 13.08%, respectively. Based on the above results, this study concluded that the ARSCM is able to replace the CRSCM in practical sowing processes for the optimal and uniform seed distribution in the field. [ABSTRACT FROM AUTHOR]

Spelt wheat is one of the oldest wheat with very high nutritional value. It does not have particular climatic requirements and tolerates adverse environmental conditions well. The versatile advantages of spelt wheat make it attractive to farmers, plant breeders, food technologists, and consumers. The aim of this study was to determine the effect of different crop protection systems and seeding densities on yield, weed infestation, and grain health of the spelt wheat cultivars "Rokosz" and "Schwabenspelz". The research showed that the spelt wheat cultivars studied responded differently to production intensification. The use of crop protection chemicals in the crop of the cultivar "Rokosz" resulted in lower weed infestation and in obtaining higher yields. In the case of the cultivar "Schwabenspelz", production intensification did not have a significant effect on its productivity and quantitative weed infestation parameters. Therefore, this cultivar can be recommended for cultivation in farms with extensive farming methods, for example, in organic farms. In both cultivars studied, an increase in seeding density and chemical plant protection with fungicide caused lower grain contamination with mycotoxins, and the content of individual mycotoxins did not exceed the maximum levels set for grain intended for food and animal feed purposes. [ABSTRACT FROM AUTHOR]

Seeding rate for maximum grain yield can differ for diverse hard red spring wheat (HRSW) (Triticum aestivum L.) cultivars and is derived from a yield response curve to seeding rates. Six groups of HRSW cultivars with combinations of Rht-B, Rht-D, and Ppd-D genes were planted at five seeding rates in 21 environments during 2013–2015 throughout Minnesota and eastern North Dakota, USA. Seeding rates ranged from 1.59 to 5.55 million seeds ha−1 and planting timings were optimal and delayed dates. An analysis of covariance predictive model with 13 predetermined training environments was built for yield and tillering, and validated with eight predetermined environments. Optimal seeding rates from the yield model were not predictive for yield, with latitude of the environment negatively skewing the predictions from observed values. A second yield model fit to only the six lowest-yielding environments (<4.8 Mg ha−1) was more predictive (R2 = 0.44), and revealed yield response to seeding rate was influenced by cultivar traits for photoperiod response (Ppd-D gene) and plant stature (semi-dwarfing gene Rht-D). The tillering model was also predictive for the validation environments, with a R2 of 0.71. Using regression predictions for yield and tillering from training and validation datasets with HRSW genetic and geographic predictors shows promise to help recommend seeding rates for future environments. [ABSTRACT FROM AUTHOR]

In order to obtain desirable crop yields, grain seeds need to be sown at the optimal seed amount per hectare with uniform distribution in the field. In previous grain sowing processes, the seeding rates are controlled by the rotational speed of the flute roller which significantly effects the uniform distribution of the seeds due to disturbances, such as the reduction of the seeds' mass in the hopper and the change of working length of the flute roller. In order to overcome the above problem, we developed an adaptive roller speed control system based on the seed flow rate sensor. The developed system can monitor and feedback actual seeding rates. In addition, based on the monitoring value of the real-time seeding rates, an adaptive roller speed control method (ARSCM), which contains an algorithm for calculating the seeding rate with a compensation, was proposed. Besides, the seeding performance of the ARSCM and that of the conventional roller speed control method (CRSCM) were compared. The results of constant-velocity experiments demonstrated that the accuracy (SA) and the coefficient of variation (SCV) of the seeding rates controlled by the ARSCM were 94.12% and 6.77%, respectively. As for the CRSCM, the SA and SCV were 89.00% and 8.95%, respectively. Under variable-velocity conditions, the SA and SCV of the proposed system were 91.58% and 11.08%, respectively, while those of the CRSCM were 88.48% and 13.08%, respectively. Based on the above results, this study concluded that the ARSCM is able to replace the CRSCM in practical sowing processes for the optimal and uniform seed distribution in the field.

Spring peanut is a valuable alternative crop to mitigate water scarcity caused by excessive water use in conventional cropping systems in the North China Plain (NCP). In the present study, we evaluated the capability of the Agricultural Policy Environmental eXtender (APEX) model to predict spring peanut response to sowing dates and seeding rates in order to optimize sowing dates, seeding rates, and irrigation regimes. Data used for calibration and validation of the model included leaf area index (LAI), aboveground biomass (ABIOM), and pod yield data collected from a field experiment of nine sowing dates and seeding rate combinations conducted from 2017 to 2018. The calibrated model was then used to simulate peanut yield responses to extended sowing dates (5 April to 4 June with a 5-day interval) and seeding rates (15 plants m−2 to 50 plants m−2 with a 5 plants m−2 interval) using 38 years of weather data as well as yield, evapotranspiration (ET), and water stress days under different irrigation regimes (rainfed, one irrigation before planting (60 mm) or at flowering (60 mm), and two irrigation with one time before planting and one time at flowering (60 mm each time) or at pod set (60 mm each time)). Results show that the model satisfactorily simulates pod yield of peanut based on R2 = 0.70, index of agreement (d value) being 0.80 and percent bias (PBIAS) values ≤4%. Moreover, the model performed reasonably well in predicting the emergence, LAI and ABIOM, with a R2 = 0.86, d = 0.95 and PBIAS = 8% for LAI and R2 = 0.90, d = 0.97 and PBIAS = 1% for ABIOM, respectively. Simulation results indicate that the best combination of sowing dates and seeding rates is a density of 35–40 plants m−2 and dates during early-May to mid-May due to the influence of local climate and canopy structure to the growth and yield of peanut. Under the optimal sowing date and plant density, an irrigation depth of 60 mm during flowering gave a pod yield (5.6 t ha−1) and ET (464 mm), which resulted in the highest water use efficiency (12.1 kg ha−1 mm−1). The APEX model is capable of assessing the effects of management practices on the growth and yield of peanut. Sowing 35–40 plants m−2 during early-May to mid-May with 60 mm irrigation depth is the recommended agronomic practice for peanut production in the water-constrained NCP. [ABSTRACT FROM AUTHOR]

Soils in tropical croplands are becoming degraded because of soil carbon (C) depletion. Local farmers in South India use a specific management of traditional cultivation, i.e., broadcast seeding. However, for sustainable C management, there is no quantitative data on the CO2 flux under this management. Our objectives were to (1) estimate the annual CO2 flux, and (2) evaluate the effect of traditional cultivation management (seeding rate) on the CO2 flux. Our field experiment was conducted in South India, from 2015 to 2017, including two cultivation periods with four cultivation management treatments (traditional cultivation management plot (T), fixed density plot (FD), no thinning plot (NT), and bare plot (B)). The seeding rate in the FD plot was ca. 50% of the T plot. We applied 1.1 Mg C ha−1 farmyard manure just before the experiment as a C input. We found that broadcasting, thinning, and cultivation increased soil moisture, while the CO2 efflux rate showed no significant difference between treatments throughout the experimental period. This indicates that cultivation management did not affect the CO2 flux. The total CO2 fluxes for two years were estimated at 2.2–2.7 Mg C ha−1. Our results indicate that it is necessary to apply larger or more frequent C inputs to prevent C depletion. [ABSTRACT FROM AUTHOR]