Explore the vast range of titles available.

There are few estimates of cardinal temperatures [T b (base), T o (optimal), T m (maximum)] for pea ( Pisum sativum L.) seed germination and seedling growth traits, with variable results, and there is almost no understanding of how these traits vary among pea varieties or classes. The objective of this controlled-environment study was to compare these among multiple varieties of food-grade winter and spring field peas and Austrian winter pea (AWP). Contrary to hypothesized outcomes, there were no collective differences in any of the three cardinal temperatures between winter- and spring-adapted food-grade field peas. Overall estimates were − 0.98 °C for T b , 27.5 °C for T o , and 37.5 °C for T m . AWP, known for exceptional cold hardiness, contrasted from the food peas in having lower T o (25.7 °C) and T m (36.1 °C). Metrics of seedling vigor and growth (germination rate and percentage, shoot elongation) were markedly higher for AWP than the food peas. The food-grade winter pea seeds were collectively somewhat more vigorous than the spring peas. Considering both cardinal temperatures and germination rate, the average thermal time requirements for 50% germination were 31.0, 46.6, and 55.9 °Cd for AWP, winter food, and spring food peas, respectively. These results provide improved metrics and understanding of field pea seedling responses to temperature.

Much research has been invested in infrared temperature (IRT)-based methods for cotton ( Gossypium hirsutism L.) water stress detection using in-field sensors, but adoption of these is low, perhaps due to logistical challenges. Alternatively, the Water Deficit Index (WDI) was developed for crop water stress assessment using remote sensors not embedded in the canopy. The objective of this research was to evaluate the performance of a sensor package—including modern IRT and normalized difference vegetation index (NDVI) sensors facing downward at 45˚, and a mini weather station—attached unintrusively to a center pivot irrigation system for detecting cotton water stress using WDI. Sensor packages were evaluated in a two-year field study that included four irrigation treatments (0, 30, 60, and 90% ET replacement) and in two production cotton fields. Overall, the tested system was effective at distinguishing crop water stress among irrigation rates. Comparison of the results to a ground-based station and simulations indicated that WDI overestimated water stress at the highest irrigation rate, but performed well otherwise. Accuracy of the system could be improved by measuring canopy coverage ( Fc ) from the same vantage point as the IRT and NDVI sensors (from the pivot, downward at a 45˚ angle).

Wheat (Triticum aestivum, L.) producers have the choice to retain or remove residue from the cropping system following grain harvest. In the U.S. Pacific Northwest and other regions, wheat residue is often sold to increase operational profitability, especially from higher-yielding systems. But there are several benefits to retaining residue, including recycling of mineral nutrients contained therein, though this is understudied. Therefore, the primary objectives of this research were to collect and analyze a large and diverse dataset on wheat residue nutrient uptake (N, P, K, Ca, Mg, S, Fe, Zn, Mn, Cu), develop tools to estimate nutrient amounts in residue, and make economic estimates of the fertilizer replacement value of those nutrients. This was accomplished by conducting replicated variety trials on five classes of wheat across many Pacific Northwest sites over two years, then collecting and analyzing data on wheat residue biomass, residue nutrient concentrations, and grain yield. The results showed that wheat residue contained a significant amount of nutrients, but was particularly concentrated in K. Production environment had the most substantial effect on residue mineral uptake amounts, due to site differences in yield and soil nutrient availability. To enable simple estimation of residue nutrient uptake across a broad range of wheat production levels, two estimation tools are presented herein. Economic analysis showed the substantial monetary value of residual nutrients. For example, in a high-yielding wheat crop (9 Mg ha−1), the average fertilizer replacement value of just residue N, P, K, and S was similar to the entire fertilizer budget to grow the crop (~ $211 vs. $ 205 ha−1), not considering micronutrients in the residue or any nutrients removed through grain harvest. In making residue management decisions, wheat producers should consider the tradeoff between the immediate economic gains of residue sale and the multifaceted benefits of residue retention, including savings on future nutrient costs.

Biological nitrogen fixation (BNF) is a key ecosystem service rendered by legumes, but quantitative information is lacking regarding BNF in the Texas Rolling Plains (TRP), an easterly portion of U.S. Southern Great Plains where cool‐season legumes can typically be grown as cash or cover crops in dryland conditions. Using three diverse cropping systems studies (Site 1, long‐term cotton [Gossypium hirsutum L.]‐cover crop systems; Site 2, short‐term cotton‐cover crop systems; and Site 3, transitional organic wheat [Triticum aestivum L.] system), our research objective was to quantify and compare BNF and associated parameters among four cool‐season legumes (Austrian winter pea [Pisum sativum subsp. Arvense], hairy vetch [Vicia villosa], crimson clover [Trifolium incarnatum], and lentil [Lens culinaris]) in different settings. At Sites 1 and 2, winter pea had growth of 2.73 to 3.44 Mg ha−1, the greatest percent N derived from the atmosphere (%Ndfa; 57.2–72.6%) and, depending on site, the greatest level of BNF (67–74 kg N ha−1). Results from the organic system (Site 3) demonstrated winter pea was also productive in growth and BNF when intercropped with wheat in N‐poor soil, with exceptionally high %Ndfa (92.7%). Hairy vetch and lentil differed in growth and %Ndfa, but had comparable BNF (46–51 kg N ha−1) at Sites 1 and 2. Growth of crimson clover was poor. This data provides insights on how cool‐season legumes differ in BNF in the TRP in a year when legume growth was average for the region. The TRP has a volatile climate, however, indicating further study is needed to fully understand the BNF benefit cool‐season legumes can provide in the region. Core Ideas Austrian winter pea and hairy vetch were the most productive legumes tested. Pea had an advantage in N fixation with relatively high %Ndfa. N fixation in hairy vetch and lentil were comparable. These legumes can play a role in sustainable agriculture in the Southern Great Plains region.

Use of nanoparticles in agriculture is anticipated to have beneficial outcomes, including the potential for improving nutrient delivery. Mesoporous silica nanoparticles (MSNPs) are hydrophilic porous materials with high surface area and charge and have been shown to be taken up and mobilized by plants. Untreated MSNPs have interacted with plant nutrition in controlled studies, but little research has been conducted in the field. In this study, we tested the impact of a commercially available MSNP technology on establishment of two turfgrasses from sprigs in North Central Florida. Treatments included combinations of MSNPs (–NP, with no nanoparticles; +NP, with nanoparticles), which were foliarly applied in dilute nutrient solution, and two rates of background fertility (high and low fertility), which were applied by granular fertilizer. All treatments were applied weekly. The MSNPs were effective in enhancing the rate of establishment in zoysiagrass (Zoysia japonica Steud.) in combination with both high and low fertility. For the low fertility +NP treatment, this substantially improved nutrient‐use efficiency, as establishment was reduced by just 7.6% compared to the high fertility –NP treatment with 75% less fertilizer. No impact was observed on bermudagrass (Cynodon dactylon (L.) Pers. × C. Transvaalensis Burtt‐Davy). Tissue nutrient concentrations indicated the nutrients most likely limiting growth were K, Mg, Ca, Zn, and Mn. The results suggest MSNPs provided more effective delivery of one or more limiting nutrients to zoysiagrass than nutrients from other sources, enhancing the rate of growth. The MSNPs offer the potential to establish turfgrasses with lower fertilizer inputs.

Guar [Cyamopsis tetragonoloba (L.) Taub] is an annual diploid legume (2n = 2x = 14) crop and is drought and heat tolerant. This crop is primarily grown for the high concentration of galactomannan gum that is present in the seed endosperm, and it can improve ecosystem services by fixing atmospheric nitrogen. However, the genetics of guar nodulation remains poorly understood. Therefore, the objective of this study was to assess the variation of nodule and plant growth traits in a set of guar germplasm. A total of 225 United States Department of Agriculture (USDA) guar accessions were evaluated for nodule traits in three runs of a greenhouse pot study. Results showed that all traits except fresh plant biomass varied significantly among genotypes (p-values < 0.05). Broad-sense heritability was high for nodule diameter, nodule weight per plant, and plant biomass production, indicating that genetic gain in these traits can be attained through the plant breeding process. This is promising, since selection for high values in these traits would be expected to increase nitrogen fixation and yield. There were strong and significant positive correlations between nodule number and both fresh and dry nodule weights (r = 0.79 and 0.71, respectively), as well as dry plant biomass and dry nodule weight (r = 0.8), indicating that greater plant growth is associated with increased nodule weight. Many genotypes were found to perform better than checks included in this study, which may be useful in guar breeding initiatives. PI288747 is top performing accession for all traits except nodule diameter which can be a good parent for breeding program. Overall, this research will help breeders enhance guar nodulation, nitrogen fixation, and yield by utilizing the scientific knowledge obtained and superior germplasm identified through this study.Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author 1 Given name: [specify authors given name] Last name [specify authors last name]. Also, kindly confirm the details in the metadata are correct.Author names are correct

As an emerging biofuel feedstock, sweet sorghum [Sorghum bicolor (L.) Moench] could perhaps most readily be integrated into sugarcane production systems where existing harvesters can be utilized to process the crop. This will require row spacing compatible with the harvesters, but the literature on row spacing and planting density in sweet sorghum is scarce and gives conflicting results. In North Florida in the 2012 and 2013 growing seasons, we therefore examined the effects of row spacing configurations (61 and 76 cm single rows, 71 by 107 cm double rows (DR), and 35.5 by 35.5 by 107 cm triple rows) and initial plant population densities (74,100; 98,800; 123,500; and 148,200 plant ha−1) on fresh biomass yield, Brix, estimated sugar yield, and stem diameter. We found no advantage of multiple row configurations (double and triple rows) in 2012 on biomass yield, Brix, or estimated sugar yield, and a definitive disadvantage in 2013 compared to the single row treatments. The 61‐cm single row treatment, which is amenable to harvest with a sugarcane harvester, yielded as well or better in 2013, depending on population density, than commonly used 76‐cm single rows, which cannot be harvested with a sugarcane harvester. The data also highlighted the cultural tradeoff that exists between increasing initial plant population density and decreasing stem diameter. Considering this tradeoff, an intermediate initial plant population density, such as 123,500 plants ha−1, was found to best optimize yield and stem diameter to facilitate sweet sorghum harvest as billets.

Precision nitrogen (N) application methods have been developed for dryland wheat that utilize site‐specific measurements of grain protein concentration (GPC) to determine N fertilizer recommendations for the next season. The objectives of this study were to determine the critical protein level and N equivalent to a unit change in GPC from relationships between GPC, and grain yield or plant‐available N in soft white winter wheat (SWW, Triticum aestivum L.), and assess the consistency of these relationships across SWW cultivars grown under a wide range of precipitation. A 3‐year study was undertaken near two sites: Lexington (225 mm of mean annual precipitation) and Adams (450 mm) in Oregon. Differences in precipitation and N fertilization rates between sites were used to induce variability in grain yield and GPC of four cultivars. A critical protein concentration of 117.5 g kg−1 was defined by Cate–Nelson analysis of scatter plots of relative yield versus GPC. Critical protein among cultivars ranged between 105 and 118 g kg−1 suggesting that 117.5 g kg−1 might be used as a general indicator of N sufficiency. Slopes of the regression of available N on GPC were consistent across cultivars and revealed that 4.2–8.4 kg N ha−1 is equivalent to a unit change protein (1 g kg−1) in lower precipitation areas of the region where SWW is under water stress during grain filling. This information is useful in calculating the N to apply from the GPC in the previous season to meet crop requirements in the next season. Core Ideas A critical Grain protein level can indicate N sufficiency for yield of winter wheat under water stress. The N equivalent to a unit change in protein concentration is generalizable across winter wheat cultivars. Critical protein level and N equivalent to unit change in protein are useful for precision N management.

Background and aim Soil salinity presents major constraint for symbiotic root-microbe interactions and overall crop productivity. While compost amendments are effective, availability is limited in drylands where salinity is prevalent. As an alternative approach, we investigated the foliar application of signaling compounds. Methods In this study, cowpea plants were evaluated under the treatments of foliar application of strigolactones (SL), salicylic acid (SA), SL and SA or SLSA, and coumarins (CMR), under soil amendment with gypsum (GP) and compost (CMP), and unamended natural saline soil as the control soil (CS) treatment. The microbiome structure in the rhizosphere, roots, leaves, and seeds were assessed, along with root traits, nodulation, arbuscular mycorrhizal (AMF) colonization, nutrient concentrations, and biomass yield. Results Several treatments exhibited positive effects, with CMP and SLSA yielding the most comprehensive improvements. The SLSA outperformed CMP in enhancing nodulation and AMF colonization. Only CMP induced a significant shift in the rhizosphere and root microbiome structure, while the leaf and seed microbiomes remained stable. An AMF Rhizophagus in the rhizosphere and AMF Diversispora in the root endosphere of SLSA treatment, and Actinobacteria and Streptomyces in the root endosphere of the SLSA treatment showed increased abundance. The increased abundance of several microbial groups with SLSA indicated their effectiveness as beneficial keystone taxa, which appears to be an influential factor for impacting salinity tolerance in the legume. Conclusions Overall, these findings confirm that the application of signaling compounds is a viable strategy for enhancing symbiotic root-microbe interactions and improving plant productivity in saline soils.

Guar [Cyamopsis tetragonoloba (L.) Taub] is a legume primarily grown for the guar gum in its endosperm, which is used in industrial, chemical, and food applications. Guar seed also contains protein, though this aspect of the crop has been much less studied. The high protein content makes it a good livestock feed source and the tender pods a nutritious vegetable for humans. The objective of this study was to evaluate seed protein content of diverse guar germplasm accessions sourced from the United States Department of Agriculture (USDA) plat germplasm repository. A two-year field study was conducted at Chillicothe and Lubbock, Texas, in 2021 and 2022. Nitrogen combustion analysis was used to evaluate protein content on ground seed samples and data was analyzed using JMP Genomics ® 7 (SAS Institute, Inc.). Significant location X year X genotype interaction (P-value < 0.05) and main genotype effects (P-value < 0.05) were identified for seed protein content. Broad-sense heritability (H) for protein content was 80.7%, indicating that most variation was due to genetics and the trait is selectable in breeding. A total of 10 guar genotypes had 0.5% higher protein content, across all locations and years, than the check genotype ‘Santa Cruz’. These findings identify high seed protein guar lines that can be used as parents in guar breeding and contribute basic knowledge on factors affecting seed protein in the crop.