Abstract The study of relationships between traits is essential for understanding the behavior of variables of interest and advancing breeding programs. In popcorn (Zea mays L. var. everta (Sturtev) L.H. Bailey), popping expansion (PE) is considered the primary quality trait, but knowledge about the impact of agronomic traits and Fusarium spp. infection, known to directly damage grain integrity, is still limited. Thus, this study aimed to investigate the impact of a set of agronomic traits and Fusarium severity on popcorn PE. Four trials were conducted in Campos dos Goytacazes, Rio de Janeiro, Brazil. A randomized block design with three replications was adopted, evaluating 127 S7 popcorn lines and collecting data on 14 variables. In each trial, phenotypic and genotypic correlations were estimated, and path analysis was performed using PE as the dependent variable. Correlations between kernel width (KW) × 100‐grain weight (W100), number of leaves (NL) × number of leaves above the ear (NLAE), and grain yield (GY) × prolificacy (PR) were high and consistent. KW and severity of Fusarium ear rot (SFER) showed the strongest negative genetic correlations with PE (−0.48 to −0.66 and −0.50 to −0.71, respectively), with direct effects confirmed by path analysis. GY exhibited a positive direct effect on PE in most trials, while the low correlation between these variables was attributed to indirect effects. These findings highlight the potential of grain morphology and resistance to FER as selection criteria to improve PE and suggest possibilities for simultaneous gains through integrated selection strategies.

Abstract A growing demand for herbal products is an opportunity for US growers to add diversity and high value crops into current rotations. Temperate tulsi ( Ocimum × africanum ) is a suitable crop for increased domestic production. In this study, we assessed how harvest frequency and harvest method influenced tulsi yield, quality, and total time to harvest. We assessed three distinct methods of harvest: (1) hand harvest, (2) mechanical harvest with a small plot combine, and (3) mechanical harvest with a swather. We paired these harvest methods with two levels of harvest frequency: a single cut per season and a double cut per season. This study was replicated in 2022 and 2023. We found no significant differences in tulsi yield when comparing hand harvest to either of the mechanical methods. Hand harvest took significantly more time compared to both mechanical methods. Quality was measured as eugenol content in dried plant material. Although eugenol means were higher overall in 2023, no clear trends emerged in the effect of harvest method or harvest frequency on eugenol content. Further research should explore how other agronomic practices can affect tulsi quality. The potential extension of this research to “true” tulsi, Ocimum tenuiflorum , and the inclusion of additional agronomic factors could help us better understand and optimize domestic tulsi production.

Abstract The effects of biochar and nitrogen (N) fertilization on soil carbon (C) and nitrogen (N) have been primarily studied in topsoil layers (0–30 cm), leaving a gap in understanding their long‐term impact on deeper soil layers. This study investigates the effects of biochar (0 (B0) and 9 t ha−1 year−1 (B+)) and nitrogen fertilization (0 (N0) and 300 kg N ha−1 year−1 (N+)) on soil organic carbon (SOC), soil organic nitrogen (SON), microbial biomass carbon, and microbial biomass nitrogen down to 150 cm. The study was conducted over 8 years in a rice field in northwest China. Results showed that biochar application increased total SOC by 27.0% and 12.2%, with and without nitrogen fertilization, respectively. Approximately 43.5%–51.8% of SOC was stored in the top 30 cm, while significant portions were found in deeper layers, indicating substantial carbon movement beyond the surface soil. Biochar also significantly increased SON in the 105‐ to 150‐cm depth, regardless of N fertilization. These results suggest that failing to consider deep soil layers could lead to underestimations of soil C and N storage in paddy systems. The findings highlight the importance of biochar and nitrogen fertilization for improving carbon sequestration and nutrient cycling in rice paddies, offering insights into sustainable soil management practices.

Upon graduating from Kansas State, she plans to pursue a career within the crop protection industry and eventually find a

Abstract Crop diversification has emerged as a crucial strategy for advancing agricultural sustainability and mitigating the impacts of climate change, while also presenting novel economic opportunities in emerging climatic zones. The burgeoning global craft beer industry has intensified interest in cultivating hops ( Humulus lupulus L.) in nontraditional regions, including Brazil, the Southeastern United States, and the Mediterranean. Traditionally adapted to temperate climates, hops must be acclimated to local conditions for successful cultivation in new environments. This study assessed various methodologies for calculating growing degree days (GDDs) and found that Method I demonstrated superior stability for both vegetative and reproductive phases, though Method II exhibited a better overall fit. While the application of T max > 30°C corrections reduced variability and enhanced R 2 values, no single method proved definitively superior. Analysis indicated elevated GDD requirements during vegetative stages, attributable to increased thermal averages across the 2‐year study period. Positive correlations between GDDs and biometric data suggest distinctive growth responses in subtropical environments compared to temperate regions. Quality evaluations revealed significant variability in bittering and aromatic compounds, with spring 2021 showing higher overall quality. These findings advocate for the viability of a double annual harvest as a strategic approach to optimizing hop production in subtropical climates. The results underscore the necessity for appropriate infrastructure to support post‐harvest processing and provide valuable insights for local agricultural stakeholders and brewing industries.

Abstract The high protein content in soybean ( Glycine max (L.) Merrill) necessitates maximizing the nitrogen (N) absorption capacity and the biological N fixation process. This study aimed to evaluate whether foliar application of molybdenum (Mo) combined with cobalt (Co) enhances the productivity, yield components, N content, and protein and oil contents of soybeans. The experiment consisted of randomized blocks with a split‐plot arrangement, with two soybean cultivars (BRS 399 Roundup Ready [RR] and BRS 284) as a main plot and the presence or absence of foliar application of Co + Mo as a subplot, during two seasons and eight replications. Foliar application was performed during the vegetative stages V3 and V5. The results revealed that foliar fertilization with Co + Mo increased the grain yield by 9.8% for BRS 399 RR in the first season and by 15.4% for BRS 284 in the second season. For BRS 399 RR, the N concentration in the leaves, protein yield, and oil content were also positively affected by the Co + Mo application. For BRS 284, only the N concentration in leaves increased in the first season, whereas the protein yield improved in the second season. However, compared with the control, the protein and N concentrations in the grains of both cultivars and seasons were not significantly influenced by Co + Mo application. The foliar application of Co + Mo had both positive and neutral effects on grain yield, protein yield, and leaf N concentration, depending on weather conditions and the soybean cultivar used, thus impacting N use efficiency.

Abstract The vegetative and reproductive development of Coffea canephora is affected by climatic variations; however, how environmental signals affect its phenology, especially across different maturation genotypes, remains poorly understood. In this study, we investigated the effects of climatic conditions on the vegetative growth, flowering, and fruiting of C. canephora genotypes during different maturation cycles. During the 2021–2022 harvest, early genotypes 104 and A1, intermediate genotype P2, and late genotype 143 were studied in Marilândia, ES, Brazil. A phenological scale of the reproductive period was developed, along with evaluations of vegetative development, productivity, and fruit maturation stages. The main flowering occurred in September. Distinct flowering patterns were found, with a large, medium bloom occurring in July in the early clones. Flowering occurred from July to October 2021 and in February and May 2022. The late genotype 143 presented the highest yield, with 92.6% of the fruits reaching the cherry stage. Compared to the other genotypes, the A1 genotype required 21% more ripe fruit to make up a bag of coffee, indicating a loss of yield in the immature stages (45%). A1 and P2 showed the highest growth. The vegetative growth rates peaked in spring and summer, which coincided with periods of the highest precipitation (86% of the annual precipitation). Factors such as long days, average minimum temperature, and humidity were associated with an increase in growth rates, whereas maximum temperature and solar radiation in summer negatively affected vegetative growth.

Abstract Reducing tillage in organic grains offers a path toward sustainable soil management. Living mulches provide a strategy for tillage reductions in organic corn (Zea mays L.) that suppresses weeds and increases system biodiversity. Yet, organically approved management strategies need to be identified that minimize living mulch competition with commodity crops. An experiment conducted at the University of Wisconsin's Arlington Agricultural Research Station from 2021 to 2022 examined both pre‐ and post‐corn planting management strategies of a red clover (Trifolium pratense L.) living mulch on clover growth, weed biomass, corn plant population, and grain yield. A 2 × 2 × 3 factorial experiment explored (1) pre‐plant tillage strategy comparing undercutting of clover versus no‐till management, (2) post‐plant flaming of clover versus no flaming, and (3) in‐season mechanical clover suppression strategies examining post‐plant use of inter‐row roller crimping and high‐residue cultivation used either alone or in combination. While corn yields remained relatively low across the experiment, averaging 4.61 Mg ha−1, both flaming and undercutting showed promise as mechanical management strategies to improve corn yield. Undercutting increased corn yields over no‐tilling by 3.15 Mg ha−1 in 2021, while inadequate clover suppression resulted in no statistical differences in 2022. Inter‐row roller crimping reduced early‐season clover heights but did not affect end of season clover biomass. Clover biomass between rows was reduced using high‐residue cultivation; however, neither in‐season clover suppression strategy influenced corn yield. While yield gaps remain, mechanical management strategies suggest viability in improving corn yields in organic living mulch systems but require further exploration.

Abstract Cover crop and N fertilization rate to malt barley (Hordeum vulgare L.) (NRMB) can affect soil residual NO3‐N that may alter pea (Pisum sativum L.) growth, yield, and quality in the malt barley–pea rotation. The effect of cover crop (oat [Avena sativa L.) cover crop vs. none) and NRMB (0, 40, 50, 60, 70, and 80 kg N ha−1) were examined on soil residual NO3‐N and pea growth, yield, and quality in the malt barley–pea rotation from 2014 to 2019 in the US northern Great Plains. Soil residual NO3‐N content increased with increasing NRMB. Cover crop biomass yield was 33%–393% greater with than without NRMB in 2015 and 2016. Pea grain yield and N uptake were 40%–41% greater for 40 than 60 kg N ha−1 of NRMB in 2015 and 45%–167% greater for 70 than 0 kg N ha−1 in 2018. Grain test weight was 27% greater with than without NRMB in 2014 and 2019. Harvest index was 22%–29% greater for 70 than 40, 60, and 80 kg N ha−1 in 2014, but 18%–33% greater for 0 than 50 or 80 kg N ha−1 in 2017 and 2019. Nitrogen harvest index was 13%–14% greater for 0 than 50 and 60 kg N ha−1 in 2015 and 2019. Straw yield, N concentration, N uptake, and grain protein concentration were 10%–34% greater with than without NRMB. Nitrogen fertilization to malt barley enhanced pea yield and quality, regardless of cover cropping, in the malt barley–pea rotation in the northern Great Plains.

Abstract Weed detection is essential for efficient weed management, but agricultural environments and the similarity between crops and weeds make detection challenging. Current deep learning methods often face issues like limited scenario variations, insufficient image samples, and low detection accuracy. Furthermore, weeds and crops vary in shape and color at different growth stages, complicating detection further. To address these issues, we propose a high‐precision identification method based on You Only Look Once (YOLO‐D) model, for sugar beet (Beta vulgaris) and weeds at different growth stages. The model uses the FasterNet‐S backbone to improve feature expression capability and receptor field coverage while maintaining high detection speed. It also introduces the C2F module, incorporating more residual connections to enhance gradient flow within the network structure. An efficient decoupling head is incorporated, reducing computational costs and achieving lower inference latency. The Lincoln beet dataset was used for training and evaluation. Compared to existing studies, the proposed YOLO‐D model achieves an overall mean average precision (mAP) improvement of 3.3%, reaching 75.8%. The mAP for sugar beet increases by 1.6%, reaching 87.3%, and the mAP for weeds increases by 5.1%, reaching 64.4%. On the public sesame (Sesamum indicum) dataset, “crop and weed detection data with bounding boxes,” it achieves a high mAP of 88.9%, with an overall mAP increase of 1%.