Search

Agricultural markets remain major issue downgrading root and tuber crop farmers who form the mainstream of the agricultural producers in Malawi. Recent evidence however reveals that orange‐fleshed sweet potato (OFSP) (Ipomea batatas) is currently being sold in produce markets along with the non‐orange varieties, sometimes in differentiated form in Malawi. The main objective of this study was to examine factors affecting market participation of sweet potato farmers in southern region of Malawi. Using a double‐hurdle model, this paper analyzed both the factors affecting farmer decision to participate and the extent/intensity of participation in market. The first tier of the double hurdle focused on decision to participate in the market using probit model and the second tier addressed factors affecting intensity of participation using truncated normal regression model. The paper used data collected from 360 farmers in southern districts of Malawi. Out of 360, 146 farmers had grown OFSP in the season preceding the survey. Double hurdle results indicate that farm size, output, age of a farmer (household head), and early maturing trait significantly determined decision to participate in the market. Further, results on intensity of participation indicate that access to market training, farm size, asset value, and output positively determined the intensity and negatively determined by distance to main market and gender of a farmer (household head). Based on the research findings, higher output levels and early maturing trait were found to increase smallholder farmer market participation. It is therefore recommended that strategies aimed at increasing household capacity to produce surplus produce through market tailored extension messages and productivity enhancement technologies could be highly effective in fostering smallholders' participation in commercial markets. Again, enhanced capacity building of research institutions to breed sweet potato varieties based on market demand is pivotal for increased market participation. Furthermore, research suggests that improving smallholder farmers' access to market price information, asset value, and farm size can help increase their intensity in the market. Therefore, it is critical for policymakers to holistically comprehend these socioeconomic factors in order to address the issue of smallholder farm households' decisions about market participation and the degree to which they participate. Core Ideas: Orange fleshed sweet potato is currently being sold along with non‐orange varieties, sometimes in differentiated.Decision to participate in market is significantly influenced by output, farm size, age early maturing attribute.Market intensity is determined by access to training, distance to market, farm size, gender, asset value and output.Breeding programs should integrate both sensory and agronomic traits such as early maturity and good taste. [ABSTRACT FROM AUTHOR]

Simulation modeling of perennial fruit tree growth, structure, and physiology over multiple years is particularly difficult and has lagged behind modeling of other crops because fruit trees are indeterminate organisms that grow over several growing seasons, vary widely among individuals, and have their structures modified by variable pruning practices. Nearly 30 yr of research have been devoted to developing a mechanistic, virtual tree model to simulate peach [Prunus persica (L.) Batsch] fruit tree growth, structure, and physiology. Details of much of this work have been published in several research papers in a variety of journals over a couple decades. The goal of this review is to report on the entire project and provide an overview of the approach we took in such an endeavor. This review contains excerpts of numerous previously published papers and some comments and conclusions about the value of the modeling that has occurred. Core Ideas: Modeling tree crops is especially difficult because they are long‐lived and highly variable.L‐systems are ideally suited to deal with the complexity of tree structure and function.Carbon partitioning in trees can be modelled as collections of semi‐autonomous organs.Similar processes can be used to model water relations of trees.Estimates of woody biomass of trees can be used to model annual dynamics of tree carbohydrate storage. [ABSTRACT FROM AUTHOR]

Spring dead spot (Ophiosphaerella spp.; SDS) is one of the most detrimental diseases to warm‐season turfgrasses, particularly bermudagrass (Cynodon spp.), growing in climates where cold temperatures induce dormancy. The pathogen can infect the crowns, stolons, rhizomes, and roots of bermudagrass most of the year, but infection in the fall predisposes the turf to winter injury and plant death. Symptoms typically appear the following spring, making management of SDS challenging. Moreover, the biology, epidemiology, and management of SDS are not fully understood. Ample research has been conducted on SDS which was thoroughly summarized before 2009 by Tredway et al. Since then, 18 new research papers have been published over the last 15 years that have further clarified the biology, epidemiology, and management of SDS. This review seeks to compile, update, and summarize research developments on SDS from 2009 to 2024. Research developments over the last 15 years include an increased understanding of the biology and infection mechanisms of the Ophiosphaerella species that cause SDS, a greater knowledge of the epidemiology of the disease and factors that affect its distribution, as well as improved cultural and chemical management practices for SDS. [ABSTRACT FROM AUTHOR]

Cool‐season turfgrasses widely used on golf courses, athletic fields, and other landscapes are environmentally and economically important, but they are functionally and aesthetically damaged under prolonged exposure to high temperatures because of their sensitivity to heat stress. Because the consequences of climate change include elevated global temperatures, it is necessary to understand mechanisms underlying heat tolerance in cool‐season turfgrasses to improve heat tolerance and maintain high‐quality turf during the summer, when heat stress is most severe. This paper identifies major metabolic pathways associated with genes differentially expressed in heat‐tolerant cultivars or species of different turfgrasses by overviewing research from studies using comparative transcriptomics, proteomics, and biotechnological approaches and provides insight into progress toward elucidating the genetic and molecular factors regulating heat tolerance in cool‐season turfgrasses. Key molecular factors and genes associated with heat tolerance in cool‐season turfgrasses include those in the following cellular and metabolic processes or pathways: (1) cell cycle and DNA synthesis, replication, stability, and binding factors; (2) heat shock proteins for stress protection and protease enzymes controlling protein degradation or turnover; (3) carbohydrate metabolism for chloroplast development, chlorophyll degradation enzymes regulating the stay‐green phenotype, photochemical efficiency, carboxylation, and cytochrome respiratory activities; (4) activation of antioxidant metabolism for oxidation protection; (5) modulation of lipid saturation and composition to maintain cellular membrane integrity; and (6) upregulation of secondary metabolism for stress defense. Understanding how these regulatory mechanisms cohesively operate during heat stress will facilitate the development of cool‐season turfgrass germplasm with greater heat tolerance through breeding and biotechnological methods. [ABSTRACT FROM AUTHOR]

Coffee is an important crop with economic and social importance in several countries. With a daily consumption estimated at 2.2 billion cups, its sustainability is facing critical challenges given the projected climate changes. Coffea arabica, which represents ∼60% of the global market coffee is a delicate crop, quite susceptible to diseases and biotic stresses. Developing climate‐resilience cultivars is necessary, and it includes coffee plants adapted to new farming conditions that can meet the demand for biotic and abiotic tolerance and quality. In this context, Coffea canephora emerges as a potential candidate if the crop combines plasticity and cupping quality. Plant plasticity refers to adjusted phenotypic performance when grown in different environments, a fact that may help mitigate the detrimental effect of climate changes. In this study, using a multiple environment trial, we combined genomic and genotype‐by‐environment analyses to answer the following main question: How the climate effects may affect the phenotypic plasticity in C. canephora? Our contributions in this paper are fourfold: (i) we draw attention to the cupping quality and yield performance of C. canephora cultivars when evaluated in high‐altitude and cold weather, (ii) we compared C. arabica and C. canephora phenotypic plasticity and highlight genotypes with broad and specific adaptation to certain environmental conditions, and finally, (iii) using stochastic simulation, we emphasize the potential of molecular breeding in the long term in coffee. Altogether, we present an emerging view on how C. canephora could be a valid alternative for climate‐smart cultivars in a projected scenario of altered climatic conditions. Core Ideas: Coffee sustainability is facing critical challenges given the projected climate changes.Inference on plant plasticity can identify plants more subjected to genotype‐by‐environment interaction, and therefore mitigate the detrimental effect of rapidly changing climate.Analyses of Coffea canephora phenotypic plasticity highlighted genotypes with broad and specific adaptation to certain environmental conditions.Results shed new light on the use of C. canephora as an alternative for climate‐smart coffee cultivars. [ABSTRACT FROM AUTHOR]

Seed increase through manual pollination is a critical part of maize breeding and genetics research to advance generations in breeding programs, to create desired research crosses, and produce hybrid seed for trials. Pollination in the field and in controlled environments relies on the availability of high‐quality pollen at the time that recipient silks are receptive. Generally, pollinations are made by capturing pollen from the tassel in a paper pollinating bag placed on the tassels one day prior to pollination and newly released pollen is then transferred to silks on the target plant. In the field, maize pollen is only viable for one to four hours following dehiscence and the rate of desiccation is influenced by environmental conditions. We have developed a method which increases the lifespan of pollen and allows pollen from a single tassel to be used to pollinate many ears by mixing fresh pollen with a dilutant that can be stored for multiple days. We identified characteristics of the size of suitable substrates and selected a PEEK‐based substrate for regular utilization. We evaluated pollen viability and empirically demonstrated the capability to store pollen up to 9 days when pollen is mixed with a PEEK substrate and stored at 6°C. The pollen storage method was used to make successful pollinations across 24 maize inbred lines tested and was generally equivalent to the standard manual pollination process. This method has the potential to increase the efficiency of breeding operations and may be useful in an array of genetic studies. Core Ideas: Manual pollinations in breeding and genetics research requires pollen available when recipient silks are viable.The method collects and stores maize pollen for at least 5 days and facilitates efficient pollination.Pollen is mixed with polyetheretherketone and uses field‐collected pollen and simple storage conditions.The method can increase the number of pollinations per tassel and generates a reasonable number of viable seeds. [ABSTRACT FROM AUTHOR]

Limited availability and access to quality seed is a major challenge faced by the Kenyan potato subsector. Smallholder farmers cultivate the bulk of potato mainly planting seed from informal sources without any quality assurance which contributes to low yields. In recent years, private sector businesses have engaged in certified seed potato production with positive impact on the volumes available, relying on minitubers to multiply in the field over three to four generations. Rooted apical cuttings (RACs) provide a productive alternative starter material that can further boost the Kenyan seed systems. Stokman Rozen Kenya Ltd (SRK) is a private sector business that has embraced this technology in 2017. Also, small‐scale nurseries have recently started the commercial production of cuttings. They both sell RACs mainly to seed growers for further bulking, but ware potato farmers can also produce quality seed on‐farm for their own use from RACs when applying good agricultural practices. This paper examines the initial experiences of both SRK and small‐scale nurseries in the production and marketing of RACs as well as their performance during subsequent field multiplications. Producing and selling RACs offers a profitable business opportunity, especially when productivity and sales increase. Compared to other rapid multiplication technologies, RACs also allow to significantly increase the volumes of early generation seed produced. Key recommendations are to create awareness and to develop adequate marketing strategies to promote their uptake, and to ensure RACs are adequately multiplied into commercial seed to improve its availability to smallholder farmers in Kenya. Core Ideas: Rooted apical cuttings are produced from tissue culture plantlets and planted in the field to produce seed tubers.Rooted apical cuttings have the potential to significantly boost the production of quality seed potato in Kenya.Rooted apical cuttings are recognized under Kenya's seed regulations as the same as tissue culture (G0 seed).Key challenges are to create wider awareness of rooted apical cuttings and to develop market demand.Each (seed) potato producer should assess well in advance his/her management capacities of rooted apical cuttings. [ABSTRACT FROM AUTHOR]

Transgenes have been successfully commercialized for qualitatively inherited insect and herbicide resistance traits that show similar effects across genetic backgrounds. However, for quantitative traits like yield, genetic background may affect the measured transgene value. In this paper, we evaluated whether different genetic backgrounds impact the estimated value of a transgene for grain yield, plant height, and anthesis‐silking interval for maize by developing isogenic pairs of lines with and without a transgene and testing them in hybrid combination with non‐transgenic lines from a complementary heterotic group across eleven environments in the United States. Over all hybrid combinations, the transgene increased yield by 0.2 Mg ha−1. Across multiple non‐transgenic lines of the opposing heterotic group, the transgene effect within a line pair ranged from an increase of 0.8 Mg ha−1 for the NSS4 (non‐stiff stalk) and SS7 (stiff stalk) transgenic lines to a reduction of 0.3 Mg ha−1 for the NSS5 transgenic line when compared to their non‐transgenic isoline. Transgenic hybrids were often taller than non‐transgenic hybrids (p < 0.05). Anthesis to silking interval was reduced by four growing degree days overall, but no transgene × genotype interaction was detected among line pairs. Our results show the importance of testing transgene efficacy across a large sample of elite hybrid pairs to assess the gene's value. By only testing in a specific hybrid background, as may be done for qualitative traits like insect resistance, transgenes could be erroneously advanced or eliminated. Core Ideas: Effective transgenes for complex traits are difficult to identify due to large transgene × germplasm interactions.The effect of a transgene affecting yield under drought stress was positive or negative depending on genotype.Testing transgenes for complex traits in many genetic backgrounds help to quantify their value for breeding. [ABSTRACT FROM AUTHOR]

Mega‐environment (ME) analysis is analysis of multi‐year, multi‐location crop variety trial data conducted in a target region of a crop to understand the magnitude and nature of genotype‐by‐environment interaction (GE) of the crop in the region. If repeatable GE patterns are identified, then the target region must be divided into subregions or MEs. Breeding and utilizing ME‐specific cultivars will convert the repeatable GE into genotypic main effect (G) within ME, thereby improving heritability (selection reliability) and selection gain and maximize regional and overall productivity. If no repeatable GE is found, then the target region must be treated as a single ME and the GE must be accommodated by testing adequately, that is, at a sufficient number of locations in a sufficient number of years. This paper presents a theoretical framework of ME analysis, describes graphical tools to reveal the which‐won‐where patterns in a genotype‐by‐environment dataset, and demonstrates LG (location‐grouping) biplot analysis for revealing repeatable GE patterns and delineating MEs. The concept of G + GE or GGE, that is, GE relative to G, is emphasized. It is the relative GE that is the basis for ME analysis and breeding for specific adaptation; absolute magnitude of GE has little relevance for these purposes. Breeding ME‐specific oat cultivars in Canada is demonstrated with a real‐world example. Core Ideas: Proper mega‐environment analysis is a prerequisite for effective cultivar development.Mega‐environment delineation must be based on repeatable genotype‐by‐environment interaction patterns.Location‐grouping (LG) biplot is an effective graphical too for mega‐environment analysis.Examples were provided for mega‐environment analysis.An example was provided for breeding mega‐environment‐specific oat cultivars. [ABSTRACT FROM AUTHOR]

Parasitic Striga weeds severely damage cereal crops in sub‐Saharan Africa (SSA), leading to yield losses in susceptible varieties. A range of Striga control methods are commonly recommended, including cultural practices, chemical herbicides, biological control agents, and host resistance, either as solo treatments or in combinations of these approaches (i.e., integrated Striga management [ISM]). A limited number of studies compared the relative efficacy of the recommended Striga control methods, or their combinations for ISM, in cereal crop production in SSA. The objective of this paper was to undertake a meta‐analysis and provide a detailed comparison of the Striga control methods in the production of maize, sorghum, and the major millets, as a guide to effective Striga management. The study was conducted as a meta‐analysis of 66 research articles that reported on various control measures. The following agronomic data were collected: grain yield (GY) response of the assessed crops and Striga parameters such as damage rating score (SDR) and emergence count (SEC). Maize varieties possessing Striga‐resistant genes displayed high mean yield values at 2053.00 kg ha−1, varying from 281.00 to 6260.00 kg ha−1, and a mean SDR of 4.70, ranging from 2.00 to 7.00. Likewise, sorghum varieties with Striga resistance genes achieved greater GY with a mean yield response of 1738.00 kg ha−1, ranging from 850.00 to 2162.00 kg ha−1. A relatively low GY was achieved in maize and sorghum production when deploying ISM (e.g., cultural control + host resistance and host resistance + chemical herbicides) and chemical Striga control. Effective ISM and pre‐ and post‐emergent herbicides have not yet been identified for Striga control and yield gains. Striga damage negatively affected GY in maize, as revealed by the significant correlation (r = −0.36, P < 0.001) between GY and SDR. A relatively weak correlation was detected in maize between GY and SEC (r = 0.003, P = 0.96). Sorghum GY was negatively correlated with SEC, although nonsignificantly (r = −0.30, P = 0.36). Few studies have evaluated Striga control methods in pearl millet and finger millet, limiting the opportunity for an effective comparison. The study recommends SDR as the best selection criterion for improving GY performance in maize, while SEC and SDR are the parameters of choice in sorghum selection programs for better GY under Striga infestation. Overall, the meta‐analysis indicates that host resistance is the most effective method for controlling Striga infestation and boosting GY in maize and sorghum. There is an ongoing need for research into the best combinations of the reported control methods as a sound basis for the recommendation of an ISM package across target production environments of common cereals in Africa. Core Ideas: Maize and sorghum varieties that are resistant to Striga displayed high mean yield values under Striga infestation.Effective ISM and pre‐and post‐emergent herbicides have not yet been identified for Striga control and yield gains.Host resistance is the most effective method for controlling Striga and boosting yield in maize and sorghum.There is a need to investigate the best combinations of the reported control methods to recommend an ISM package.Few studies have evaluated Striga control methods in pearl millet and finger millet limiting effective comparison. [ABSTRACT FROM AUTHOR]

The severity of herbicide injury to dormant zoysiagrass (Zoysia spp.) increases with increasing green leaves at treatment time, but injury also occurs following treatment to fully dormant zoysiagrass, especially when treatment precedes rapid shoot emergence. Research was conducted to determine the persistence of radio‐labeled glyphosate or glufosinate on dormant zoysiagrass leaves, to assess how simulated raindrop quantity affects relocation of glyphosate plus colorant to subcanopy areas, and to evaluate the response of post‐dormant zoysiagrass to glyphosate dislodged and relocated from dormant leaves via simulated rainfall, dew, or disturbance during post‐dormancy growth. When dormant zoysiagrass leaves were treated with 14C‐glufosinate or 14C‐glyphosate, 69% and 57%, respectively, of the herbicides were water extractable for 21 days. Increasing the number of simulated raindrops 0.5 cm−2 from 1 to 20 removed >95% of the applied colorant from treated dormant zoysiagrass leaves, with concomitant relocation of residue to underlying filter paper. Maximum exposure of a single subtending green shoot occurred at five simulated raindrops 0.5 cm−2, which would approximate a rainfall of 3.35 mm. Subsequently, glyphosate applied to dormant zoysiagrass plugs followed by 3 mm simulated rainfall or dew and wiping 7–9 days later, when turf had reached 15% green cover, reduced zoysiagrass clipping biomass by 35% and 72%, respectively. Glyphosate applied to dormant zoysiagrass can dislodge and injure newly developing green shoots during transition. This injury can be mitigated by irrigating 1 day after glyphosate treatment to dormant turf or ensuring that the first irrigation or rainfall following treatment is at least 12 mm. [ABSTRACT FROM AUTHOR]

The African Potato Association (APA) is highlighted in the May-June issue of Crop Science for its efforts in promoting research and development in the potato and sweetpotato sectors in Africa. Despite a decrease in government agricultural spending, the APA remains committed to enhancing research dissemination and fostering collaborations among researchers within and beyond Africa. The special section in the journal features 30 papers from the 12th Triennial APA Conference, aiming to connect researchers, practitioners, and public and private sectors for effective product and program development. The introduction to the special section can be accessed through the provided link. [Extracted from the article]

Copyright of Crop Science is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Knowledge of water use rates and responses to deficit irrigation practices in cool‐season turfgrasses is important, particularly in climates where irrigation is required to maintain turf quality. This is Part I of two companion papers reviewing cool‐season turfgrass water use and requirements. Part I presents the history of early water conservation and quantification methods in turfgrass and summarizes research on cool‐season turfgrass evapotranspiration (ET) and deficit irrigation. Part II summarizes research on cool‐season turfgrass drought resistance completed since 1980. Summaries of research from > 60 experiments related to ET include: measured ET rates in various climates; comparisons of actual ET to estimated ET; crop coefficients; deficit irrigation; and how plant characteristics and management practices influence ET. Summarized daily evapotranspiration (ETc) rates for Agrostis L. spp., fine fescues (Festuca L. spp.), tall fescue (Festuca arundinacea Schreb.), Lolium spp., and Poa spp. were a weighted average ETc and coefficient of variation (CV) of 6.12 (19.0%), 5.52 (16.8%), 7.79 (14.5%), 5.90 (19.9%), and 5.35 (30.2%) mm d–1, respectively, with an overall ETc of 6.25 mm d–1 (26.9%). Average crop coefficients have ranged from 0.85 to 0.95 (0.91 weighted average across species) and vary slightly during growing months. Minimum deficit irrigation replacement levels for acceptable turf quality have ranged from 59 to 74% of ET under different irrigation intervals. Further study is warranted to investigate differences in crop coefficients among cultivars within species, cultural influences, deficit irrigation replacement levels, and to standardize measurement protocol to improve consistency in crop coefficients across future turfgrass experiments. Core Ideas: A brief history of early water conservation research in turfgrass is presented.Evapotranspiration and deficit irrigation research in cool‐season turfgrasses is summarized.Average cool‐season turfgrass evapotranspiration rates ranged from 5.35 to 7.79 mm d−1.Average cool‐season turfgrass crop coefficient rates ranged from 0.85 to 0.95.Minimum deficit irrigation replacement levels have ranged from 59 to 74% of ET. [ABSTRACT FROM AUTHOR]

Datura stramonium L. (jimsonweed) from the Solanaceae family is widely used in traditional medicine due to its medicinal properties. This paper investigated the effect of three levels of urea fertilizer (60, 120, and 180 kg ha–1) and three levels of planting density (6, 10, and 14 plants m−2) on the grain alkaloids, chlorophylls a and b content, carotenoids, anthocyanins, and grain and biological yields. A factorial experiment as a randomized complete block design was carried out at the Research and Education farm of Isfahan Agricultural and Natural Resources and Training Center in IRAN in 2018 and 2019. Significant differences were detected between urea levels and plant density for leaf chlorophyll content, carotenoids, and anthocyanins at the 1% probability. Also, hyoscyamine alkaloid levels and scopolamine content are affected by the urea levels at the 1% probability. Moreover, the relationship between phytochemical characteristics and alkaloids with the grain and biological yields in D. stramonium is investigated by path analysis. The results showed that grain yield, hyoscyamine alkaloid levels and scopolamine content is significantly improved by 6 plants m−2planting density and 180 kg ha–1 urea. Core Ideas: The effect of plant density and urea levels on the content of tropane alkaloids in Datura stramonium L. was investigated.The effect of physiological traits and tropane alkaloids on grain and biological yields were further studied by path analysis.Grain yield is significantly improved by 6 plants m−2 planting density and 180 kg ha−1 urea. [ABSTRACT FROM AUTHOR]

Plant breeding is fundamentally comprised of three cyclic activities: (a) intermating lines to generate novel allelic combinations, (b) evaluating the newly created lines in diverse environments, and (c) selecting superior individuals to be used as parents in the next breeding cycle. While digital technologies and tools are commonly utilized for the latter two stages, many plant research programs still rely on manual annotation and paper tags to track the crosses that constitute the basis of a plant breeding program. This presence of analog data is a crack in the foundation of a digital breeding ecosystem and a significant occasion for errors to be introduced that will propagate through the entire breeding process. However, implementing digital cross tracking into breeding programs is difficult due to the nonstandardized workflows that different breeders have adopted. Intercross, an open‐source Android app, aims to provide scientists with a robust and simple solution for planning, tracking, and managing the crosses being made each season and aims to serve as the primary tool to digitize crossing data for breeding programs. The simplicity and flexibility of Intercross allows rapid and broad adoption by diverse breeding programs and will solidify the concepts of a digital breeding ecosystem. Core Ideas: Collecting crossing information is key to maintaining a digital data ecosystem. Intercross is an app that streamlines crossing data and metadata collection. Intercross can be utilized in diverse plant breeding programs. [ABSTRACT FROM AUTHOR]

Breeding programs are increasing efforts towards demand‐led breeding approaches to ensure that cultivars released meet the needs of end users including processors, traders, and consumers, and that they are adopted by farmers. To effectively deploy these approaches, new tools are required to better understand and quantify the degree of preference differences among alternative trait changes competing for measurement and selection effort. The purpose of this study was to present a method of quantifying preferences and developing typologies according to breeding priorities by applying an online trait preference survey approach to cassava (Manihot esculenta Crantz). This paper presents a conjoint analysis based on Potentially All Pairwise RanKings of all possible Alternatives (PAPRIKA) to help guide breeding programs in understanding trait preferences across value chain roles and social contexts and set breeding priorities that represent diverse interests. Trait preferences were assessed using a comprehensive survey and analysis package incorporating a core adaptive conjoint method (1000minds, 2020). Trait selection was based on a trade‐off of 11 cassava traits carried out with 792 cassava value chain actors in four geopolitical regions in Nigeria. Principal component and cluster analyses revealed three clusters (typologies) of respondents according to their trait preferences. The results demonstrate the usefulness of this methodology that innovates on previous trait preference approaches to address the expanding needs of plant breeding programs within smallholder contexts. Core Ideas: Preference surveys can reflect economic importance of traits.Typologies of trait preferences give insights to understand heterogeneity of trait preferences.Typologies can guide breeding programs in exploring the needs of different market segments. [ABSTRACT FROM AUTHOR]

Combining ability effects for yield related traits can serve as selection criteria to pursue breeding for optimal biomass allocation in wheat (Triticum aestivum). The objective of this paper is to provide information based on a retrospective quantitative genetic analysis on combining ability studies of wheat for yield and yield‐related traits to predict potential genetic gains achievable in improving biomass allocation for drought tolerance and soil carbon storage. The study compares data on the general combining ability and specific combining ability effects of wheat for yield and related traits under optimum and drought stressed conditions from 40 studies around the world. Days to heading (DTH), plant height (PH), number of tillers per plant (TN), kernels per spike (KPS), 1,000‐kernel weight (TKW), shoot biomass (SB), and grain yield (GY) exhibited wide variation for general combining ability (GCA) and specific combining ability effects. Progeny performance increased by 14.30 and 4.04% for SB and GY, respectively, compared with parental values under optimum water conditions. Number of tillers and SB exhibited positive associations with GY (.45 ≤ r ≤.85, p <.05) under both water conditions. Meta effect sizes for drought stress were negative. The highest meta‐effect sizes were calculated for DTH (−4.5) followed by SB (−2.0), whereas KPS (−1.25) had the lowest. The genetic gains for PH, SB, and other yield components showed that divergent crosses involving complementary parents could enhance biomass allocation patterns in wheat. This could be used as a basis for improving biomass allocation to roots. Core Ideas: There is sufficient genetic variation in wheat genotypes for manipulating biomass allocation.The number of kernels per spike is stable under varying moisture conditions.Shoot biomass and grain yield expression are severely confounded by drought.Aboveground traits are important for indirect selection of root traits. [ABSTRACT FROM AUTHOR]

To date, more than 20 clubroot resistance (CR) loci have been reported in the Agenome of Brassica rapa; however, only a few of them has been introgressed into B. napus canola. The introgression of additional CR loci will broaden the genetic base of resistance of this crop. In this paper, we report the genetic basis of CR of B. rapa var. pekinensis cultivar 'Bilko' introgressed into B. napus, mapping this resistance using a recombinant inbred line (RIL) population developed from B. napus × Bilko- CR interspecific cross. Evaluation of the F2 and F3 populations of Bilko revealed that a single gene controls resistance to pathotype 3 in this cultivar. Quantitative trait lociseq approach using whole-genome resequencing identified a genomic region of chromosome A03 associated with this resistance in the RIL population. Single nucleotide polymorphism (SNP)-based allele-specific markers from the TIR-NB-LRR (TNL) gene Bra012688 co-segregated with this resistance, however, with 0.4-0.8% recombination. Bra012688 is located at 23,877,250-23,883,169 bp of B. rapa cultivar Chiifu-401 whole-genome assembly v.3.0, and at 378 bp downstream of another TNL gene Bra012689. Molecular markers, linked to previously reported CR loci of A03, did not co-segregate with the resistance in the RIL population; this demonstrates the need for the development of new markers for the CR loci following introgression into the recipient species. The knowledge and the SNP allele-specific markers developed in this study could be used in breeding for clubroot resistance in B. napus. [ABSTRACT FROM AUTHOR]

Human activity has created an environmental imbalance, which is reflected in climate change and resulting temperature variations, harmful levels of air quality, and more frequent and more intense meteorological phenomena, thus having significant consequences on the agricultural sector, for example, changes in soil, climate, and water characteristics as well as in available resources for agricultural production. This paper presents an agent‐based model (ABM) to evaluate the behavior of the strawberry's (Fragaria × ananassa) agricultural system in Veracruz, Mexico, to determine the degree of existing vulnerability through a dynamic assessment of agricultural risk. Development of the ABM allows the evaluation of variations in the active entities (critical variables of the model) to determine the factors that present a better crop yield. The research showed that temperature and precipitation are determining factors in strawberry quality, as they have a direct relationship with the growth and different phenological stages of the crop from an early age to a stage of greater maturity from the budding, flowering, and fruiting stages of the strawberry. [ABSTRACT FROM AUTHOR]

Kentucky bluegrass (Poa pratensis L.) is the most widely used cool‐season turfgrass for athletic fields, but its seeds germinate slowly. The objective was to determine the germination rate, seedling vigor, and seed phenotype of Kentucky bluegrass cultivars. Germination and seedling vigor tests were conducted using a seed incubator set at alternating 25/15°C (day/night) temperatures and an 8 h day−1 photoperiod. Twenty‐one cultivars were tested using two seed lots for each. Germination was most rapid among the experimental genotype PST‐T15‐44 and the commercial cultivar "After Midnight, as they took the minimum days to reach 50% germination in only 7.9–8.0 or 8.8 days, respectively. Cultivars Tirem and Volt required >12 days in both lots to reach 50% germination (12.0–13.7 days). There was a difference of 5–6 days in 50% germination between cultivars. Seedling vigor was also measured but few differences between cultivars were noted. Data on seed phenotype including seed length, width, area, circularity, and thousand seed weights (TSW) all varied by cultivar. "After Midnight" had the longest seeds (3.065 mm). "Moonlight SLT" seeds were the shortest in length (2.366 mm), narrowest in width (0.717 mm), and smallest in area (1.328 cm2). Across all cultivars, seed length and circularity were correlated with germination rate (r = 0.62, p = 0.0025; r = −0.53, p = 0.0141). Seed phenotyping could be an important tool in breeding for improved germination rate. By identifying and using rapidly germinating Kentucky bluegrass cultivars, it may be possible to establish turf more rapidly. Core Ideas: Germination vigor differs among Kentucky bluegrass cultivars.Seed size and shape were variable among Kentucky bluegrass cultivars.More rapid Kentucky bluegrass germination was associated with longer and more linear‐shaped seed.It may be possible to establish turf more quickly through Kentucky bluegrass cultivar selection. [ABSTRACT FROM AUTHOR]

Herbicide‐resistant wheat cultivars are an effective tool in controlling weeds. The CoAxium wheat (Triticum aestivum L.) cultivar conferring tolerance to quizalofop‐p‐ethyl herbicide was developed along with a bioassay to quantify traited seeds in a sample. The objectives of this study were to (1) compare a current seed soaking (SS) method with substrate imbibition (SI) method in detecting AXigen trait in two genotypes, CO14A050 (homozygous resistant‐A/D genomes) and CO14A136 (homozygous resistant‐B/D genomes), and (2) develop criteria to distinguish between trait and nontrait seedlings based on chemical injury using standard germination, linear length, and dry matter content tests. Quizalofop doses 0.0, 3.0, 4.0, and 5.0 μM were used in both methods. A soft white winter wheat, Bobtail, was used as a susceptible control. Using SS, 96% of Bobtail seedlings were classified as nontrait at 3.0 μM and 100% at 4.0 and 5.0 μM; however, using SI, only 1.0%–6.0% showed chemical injury and were classified as nontrait. The SI did not differentiate between trait and nontrait seedlings at any dose. At 5 μM, CO14A136 showed significant chemical injury (26%) compared to CO14A050 (1%). A greenhouse dose–response study confirmed that CO14A136 conferred lower tolerance to quizalofop than CO14A050. The SS method at 5 μM was suitable for identifying trait and nontrait seeds. It is recommended that both root and shoot structure should be considered in evaluating trait and nontrait seedlings, not only roots like the current protocol. Core Ideas: Seed soaking bioassay at 5.0 μM dose identified quizalofop tolerant wheat seeds effectively.Substrate imbibition method at 5–20 μM was not reliable to detect quizalofop‐tolerant seeds.Both root and shoot structures should be considered in evaluating trait and nontrait seedlings. [ABSTRACT FROM AUTHOR]

The editorial board of Crop Science has announced the recipients of the 2023 Editor's Citation for Excellence. These awards recognize the dedication and professional commitment of volunteer reviewers and editors who have contributed to the high standard and quality of papers published in the journal. The recipients were chosen based on their thorough, competent, and timely reviews or editing of manuscripts. Each recipient will receive a certificate of appreciation, an ASA‐CSSA‐SSSA gift certificate, and recognition in CSA News. The recipients include Dr. Gabriela Abeledo, Dr. Brenda Laura Gambin, Dr. Lori Hinze, Dr. Vince Pantalone, Dr. Cristiane Pilon, and Dr. Wei Wu as associate editors, and Dr. Georgia Eizenga, Dr. Jales Mendes Oliveira Fonseca, Dr. Laura Lindsey, Dr. Ntombokulunga Mbuma, Dr. Desalegn Serba, and Prof. Dr. Meiliang Zhou as reviewers. [Extracted from the article]

The article announce the recipients of the 2021 Editor's Citation for Excellence as these awards recognize the professional commitment and dedication of volunteer reviewers and editors who helped maintain the high standard and quality of papers published in the journal.

The article discusses Articles will be published under journal table of contents headings of the same name to maintain continuity and will be collated annually into year-end electronic collections.

Improving potato late blight (LB) resistance is essential for ensuring food security, particularly using wild relatives endemic to Phytophthora infestans‐prone regions. However, reproductive barriers can impede the transfer from potato wild relatives (PWR) to the cultivated genepool. This study sought to incorporate potentially novel LB resistance from wild diploid accessions of Series Piurana (Solanum chiquidenum, Solanum paucissectum, and Solanumpiurae), Tuberosa (Solanum cajamarquense), and Megistracroloba (Solanum sogarandinum) into tetraploid potato. Trough rescue pollination, 699 diploid interspecific hybrids were obtained, of which 385 displayed LB resistance in two endemic environments. Based on a comprehensive evaluation, including assessing 2n pollen production, 14 diploid interspecific hybrids were selected to continue the introgression process. These pre‐bred stocks were then used in interploidy (4x‐2x) crosses to incorporate their LB resistance in the cultivated tetraploid background. Assessment of 1978 genotypes resulting from interploidy crosses under endemic disease pressure yielded 717 hybrids with moderate to high levels of LB resistance. Evaluation of pollen viability and ploidy revealed moderate fertility and predominantly tetraploid genotypes. Reassessment of LB resistance on this new subset of hybrids further identified 214 genotypes with sustained resistance. Among them, 12 tetraploid hybrids with low glycoalkaloid content, favorable agronomic, and post‐harvest attributes were identified as crossing‐friendly stocks. Notably, 11 of these hybrids were derived from S. cajamarquense and one from S. sogarandinum. These promising 4x hybrids are now primed to be incorporated into potato breeding programs. Core Ideas: This study sought to incorporate potentially novel late blight (LB) resistance from underutilized wild relatives into tetraploid potato.Promising 4x hybrids from distant wild relatives exhibit low glycoalkaloid content and favorable agronomic traits.Overcoming interspecific barriers for novel late blight resistance alleles in potatoes was discussed. [ABSTRACT FROM AUTHOR]

Pennycress (Thlaspi arvense L.) is an emerging bioenergy oilseed crop of interest to farmers in the Upper Midwestern United States. Improved lines with beneficial agronomic traits are being developed, including lines with reduced silicle shattering and altered seed coat characteristics, though planting and establishment is still challenging for this small‐seeded crop. A controlled‐environment experiment was conducted to assess the impact of seed treatment and pelleting on pennycress germination and seedling vigor of four pennycress lines (three black and one golden colored seed) following storage for 0, 1, 3, 9, and 12 months in warm or cold conditions (23°C or 10°C, respectively). Seeds were either treated with a gibberellin A4+7 (GA) soak (positive control), seed pelleting, or pelleting with GA added to the binder solution in addition to the untreated control (negative control). After each storage duration, seeds were germinated in darkness and counted daily for 7 days to obtain total germination. Vigor indices were calculated using changes in daily germination values. For black‐seeded lines, GA treatment increased germination over the untreated by 5%–75% and pelleting alone increased germination by 4%–30%, but only until 3 months of storage. The GA treatment did not increase germination of the golden‐seeded line, and pelleting decreased germination after 3 months of storage. The GA soak treatment was most effective at improving seed vigor indices compared with other treatments, while pelleting negatively affected vigor scores at 9 and 12 months of storage. Similar effects on germination from treatment were observed under both warm and cold storage conditions. Results indicate seed treatment can benefit germination and vigor within 3 months of storage for black‐seeded lines but may negatively affect performance of golden‐seeded lines, or all pennycress seed types after 9 months of storage. Core Ideas: Black‐seeded pennycress germination improved within 3 months of treatment with both pelleting treatments.Increased germination and vigor from seed treatment reduced after 9 or 12 months in storage.Germination and vigor of the golden‐seeded line were negatively affected by seed pelleting. [ABSTRACT FROM AUTHOR]

Polyphenol oxidase (PPO) has a major effect on the time‐dependent darkening of noodle products. Development of varieties with low PPO activity is one method to eliminate this problem and respond to the demands of consumers. Among the common wheat (Triticum aestivum L.) Ppo genes, Ppo‐A1 has the highest effect on grain PPO activity, and several Ppo‐A1 alleles with low or no activity have been reported, with the recently identified Ppo‐A1i allele being the most desirable allele. In this study, reverse‐transcription polymerase chain reaction analysis confirmed that this allele was not expressed and was therefore functionally null. We also determined that Ppo‐A1i has an approximately 3 kb insertion in the second intron. Taking advantage of the insertion sequence, we developed a new co‐dominant marker, PPO18Plus, capable of distinguishing Ppo‐A1a, Ppo‐A1b, and Ppo‐A1i. In addition, we determined that the Ppo‐A1i allele is identical to and originates from the Ppo‐A1g allele of tetraploid wheat. The durum wheat (Triticum turgidum ssp. durum (Desf.) Husn.) Ppo‐A1g allele has been used to improve pasta color in durum wheat breeding programs. Thus, the PPO18Plus marker developed here will be very useful in both hexaploid and durum wheat breeding programs. Core Ideas: The null allele Ppo‐A1i in hexaploid wheat has an approximately 3 kb insertion in the second intron.The Ppo‐A1i allele is identical to and originates from the Ppo‐A1g allele of tetraploid wheat.Transcripts of the Ppo‐A1i allele could not be detected throughout seed development.We developed a new co‐dominant DNA marker, PPO18Plus, capable of distinguishing Ppo‐A1a, Ppo‐A1b, and Ppo‐A1i.PPO18Plus can be used in both common and durum wheat breeding programs for the selection of desirable PPO alleles. [ABSTRACT FROM AUTHOR]

Winter annual forages can extend grazing into the cool‐season in the US southeast, however uncertainty regarding potential tradeoffs between winter annual mixtures versus monocultures exists. We examined increasingly species‐rich and functionally diverse winter annual forage mixtures at two Florida locations to evaluate impacts of including more plant species with distinct traits (e.g., different maturities and nitrogen [N] scavenging vs. N2‐fixing capabilities) on forage accumulation (FA), nutritive value, and evenness of forage distribution across the cool‐season compared with a rye (Secale cereale L.) monoculture. Furthermore, we quantified the N2‐fixing potential of winter annual legumes to measure their contribution to soil fertility and ecosystem N cycling. We found that greater species richness enhanced total cool‐season FA at both sites, ranging from 0.92 to 4.38 Mg DM ha−1 in Gainesville and 6.48 to 9.11 Mg DM ha−1 in Marianna. In Marianna, where legumes accounted for approximately 25% or more of the biomass accumulated by winter annual forage mixtures, legume inclusion enhanced forage shoot N concentration. Furthermore, >50% of the N in legume tissues derived from the atmosphere, supplying 0.18–2 kg N ha−1 in Gainesville and 30–52 kg N ha−1 in Marianna. Altogether, our data suggest that species richness enhanced winter annual forage production and legume inclusion improved forage nutritive value although these responses were site‐specific. Thus, our multi‐site study provides information that can guide decision‐making regarding appropriate winter annual forage selections to increase cool‐season forage production in the southeastern United States. Core Ideas: Greater species richness of grasses enhanced forage accumulation of winter annuals at two Florida locations.Species richness and functional diversity were not associated with more even distribution of winter annual forages.Legume inclusion improved total forage tissue nitrogen concentration when consisting of 25% or more of the total forage.Site‐specific information can inform decisions about the most appropriate winter annual forages to adopt. [ABSTRACT FROM AUTHOR]

Improving the management of water and fertilizers is an effective method for enhancing the seed‐setting performance of rice. This study aimed to explore the regulation of optimized water and nitrogen management on the root–leaf hormone balance and seed‐setting performance of drip‐irrigated rice. In a 2‐year field experiment, T‐43 (a drought‐resistant cultivar) and LX‐3 (a drought‐sensitive cultivar) were cultivated under two drip irrigation treatments (W1, limited, and W2, deficit) and three nitrogen fertilization treatments (N1, seedling:tillering:panicle:grain‐filling, 30%:50%:13%:7%; N2, 20%:40%:30%:10%; and N3, 10%:30%:40%:20%). Compared with other treatments, the W1N2 treatment increased the seed‐setting rate and grain biomass accumulation (2.7%–9.2% and 4.5%–69.8%) of the two cultivars on the basis of producing a higher effective panicle number, and T‐43 had a much higher seed‐setting rate and yield than LX‐3 (6.8%–14.6%). Increased fertilizer applications at the panicle and grain‐filling stages (N2) enhanced the root oxidation activity (ROA) and the zeatin+zeatin riboside (Z + ZR) and gibberellic acid (GA3) contents in the roots in the 0–10 cm layer and in the leaves from the heading stage to 20 days after heading. The grain biomass accumulation of T‐43 was significantly positively correlated with abscisic acid (ABA) and Z + ZR in the roots and leaves, while the grain biomass accumulation of LX‐3 was significantly positively correlated with auxin, ABA, Z + ZR/ABA, and GA3/ABA in the roots in the 10–20 cm layer. Overall, W1N2 promoted grain biomass accumulation by modulating the Z + ZR and ABA balance in roots and leaves, improved the root–shoot ratio, and enhanced ROA, thereby improving the seed‐setting performance of drip‐irrigated T‐43 rice. Core Ideas: Optimized water and nitrogen management improved seed‐setting rate on the basis of higher effective panicles.Increasing panicle and grain fertilizer enhanced the hormone content and root activity in 0–10 cm.The balance of the hormone content in roots and leaves promoted the transport of assimilates to grain. [ABSTRACT FROM AUTHOR]

Urochloa spp. are excellent perennial forages and are among the best grasses for livestock production. The seed yield is an important trait because it impacts the seed production cost and, consequently, the cost of establishing pastures. The objective of this study was to estimate the genetic correlation between traits related to seed production in Urochloa spp. The experiment was evaluated in 2019 and 2020. Eight traits related with seed production were evaluated for 23 tetraploid progenies obtained by crossing Urochloa brizantha × Urochloa ruziziensis. There were positive correlations of high magnitude between the characters, allowing indirect selection. Two progenies showed better results in traits directly related to seed production. Days to flowering can influence the rate of seed production. The highest value for grain percentage was 20.31%. Core Ideas: The highest percentage of seed filled for Urochloa seeds was <21%.The number of days for flowering can negatively influence seed production.There was no significant negative correlation between the evaluated seed production traits. [ABSTRACT FROM AUTHOR]

Hemp (Cannabis sativa L.) is one of the world's oldest and most diversely cultivated plants, but legal constraints and a lack of agronomic rules have curtailed its production. This study aimed to determine the optimum nitrogen (N) application rate and harvesting stage for hemp yield in terms of seed, fiber, and stem. Treatments included (1) five nitrogen application rates (control [N0], 60 kg ha−1 [N60], 120 kg ha−1 [N120], 180 kg ha−1 [N180], and 240 kg ha−1 [N240]) and (2) three harvesting stages: before flowering (HS1), during flowering (HS2), and at the end of flowering (HS3). A 2‐year field experiment was conducted with three replicates. Harvest stages were randomly distributed over N rates in both years. The following agronomic parameters were evaluated: plant height, stem diameter (lower, middle, upper), number of leaves/plant, leaflet width, leaflet length, dry stem yield, fiber yield, and seed yield. The highest stem yield and fiber yield were obtained in the 240 kg ha−1 N treatment, and also the highest fiber (bast) yield and dry stem (hurd fiber) were obtained flowering and at the end of the flowering stages, respectively. When nitrogen application rate was increased from 0 to 240 kg ha−1, plant height, stem, and fiber yields increased by 48%, 65% and 57%, respectively. Agronomic parameters increased significantly (p < 0.01) when the harvesting time was moved from "before flowering" to "at the end of flowering." Core Ideas: The highest hemp stem yield (1136.2 ± 45.4 kg ha−1), fiber yield (309.9 ± 20.0 kg ha−1), and seed yield (120.0 ± 14.1 kg ha−1) were determined in the 240 kg ha−1 N.Increasing N doses from control to 240 kg ha−1 plant height, stem, and fiber yield increased by 48%, 65% and 57%, respectively.Higher fiber yield and yield parameters were achieved during the flowering stage. [ABSTRACT FROM AUTHOR]

Depending on the trait architecture and reproduction system, selection strategies in plant breeding focus on the accumulation of additive, dominance effects, or both. Innovation in the exploitation of dominance‐effect‐based heterosis has been limited since the proposal of general combining ability (GCA)‐based approaches. We propose the use of a new surrogate of genetic complementation between genetic pools to increase accumulation of dominance effects and heterosis. We simulated breeding programs to show how reciprocal recurrent selection (RRS) by genetic complementation would build the dominance‐based heterosis cheaper than GCA‐based approaches and used real phenotypic data from hybrid maize (Zea mays) to demonstrate the underlying concepts. We found RRS by genetic complementation to be an attractive and viable strategy to exploit dominance, build de novo heterotic pools, and enhance the current GCA‐based approaches. If demonstrated in practice, we hypothesized that this approach would lower the cost of hybrid breeding drastically and contribute to food security. Core Ideas: Heterotic patterns can be developed quickly through the genetic complementation metric proposed.Complementation can produce high‐performance heterotic pools at a low cost in diploid species displaying dominance.Complementation can enhance general combining ability‐based recycling approaches in hybrid breeding. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa L.) ratooning is one of the most essential production strategies to increase grain yield. Field experiments were conducted in southwestern Japan in 2021 and 2022 to determine the effects of planting date and cutting height of the first crop on grain yield. Grain yield of the second crop was higher at early planting date than at late planting date in 2021, but the yield difference was narrowed in 2022. The higher grain yield at early planting date resulted from the higher number of spikelets and percentage of filled spikelets due to the higher stubble nonstructural carbohydrate (NSC) content, leaf area index (LAI), and air temperatures. Grain yield of the second crop was higher at high cutting height than at low cutting height in 2021, but the yield difference was narrowed in 2022. The higher grain yield at high cutting height resulted from the higher number of spikelets due to the higher NSC content and LAI. In the weather conditions, grain yield had a strong positive correlation with the air temperature, which had positive correlations with the number of panicle and percentage of filled spikelets. In the stubble conditions, grain yield had a strong positive correlation with NSC content, which had positive correlations with the number of panicle and percentage of filled spikelets. Therefore, early planting, which secures high air temperatures, and high cutting height, which produces high NSC content, are recommended to increase grain yield of the second crop. Core Ideas: Early planting date generally had higher yield of the second crop.Yield difference of the second crop between planting dates was narrowed under high air temperature condition.High cutting height generally had higher yield of the second crop than low cutting height.Yield difference of the second crop between cutting heights was narrowed under high air temperature condition.Early planting and high cutting height are recommended to increase yield of the second crop. [ABSTRACT FROM AUTHOR]

High‐throughput phenotyping (HTP) with unoccupied aerial systems (UAS), consisting of unoccupied aerial vehicles (UAV; or drones) and sensor(s), is an increasingly promising tool for plant breeders and researchers. Enthusiasm and opportunities from this technology for plant breeding are similar to the emergence of genomic tools ∼30 years ago, and genomic selection more recently. Unlike genomic tools, HTP provides a variety of strategies in implementation and utilization that generate big data on the dynamic nature of plant growth formed by temporal interactions between growth and environment. This review lays out strategies deployed across four major staple crop species: cotton (Gossypium hirsutum L.), maize (Zea mays L.), soybean (Glycine max L.), and wheat (Triticum aestivum L.). Each crop highlighted in this review demonstrates how UAS‐collected data are employed to automate and improve estimation or prediction of objective phenotypic traits. Each crop section includes four major topics: (a) phenotyping of routine traits, (b) phenotyping of previously infeasible traits, (c) sample cases of UAS application in breeding, and (d) implementation of phenotypic and phenomic prediction and selection. While phenotyping of routine agronomic and productivity traits brings advantages in time and resource optimization, the most potentially beneficial application of UAS data is in collecting traits that were previously difficult or impossible to quantify, improving selection efficiency of important phenotypes. In brief, UAS sensor technology can be used for measuring abiotic stress, biotic stress, crop growth and development, as well as productivity. These applications and the potential implementation of machine learning strategies allow for improved prediction, selection, and efficiency within breeding programs, making UAS HTP a potentially indispensable asset. Core Ideas: UAS imagery can be useful in plant breeding programs for routine trait and previously infeasible trait measurement.High‐throughput phenotyping approaches to date differ among crops and each could learn from others.Example applications of UAS imagery are provided for breeding programs of four major crops.The rise of phenomics tools is likely to prove similarly useful to current genomic tools. [ABSTRACT FROM AUTHOR]

Lodging can reduce the yield and quality of oats (Avena sativa L.). Root lodging, as opposed to stem lodging, is the predominant form of lodging in oats. Therefore, identifying management practices that enhance root lodging resistance should be prioritized. The objective of this study was to investigate the effect of four management practices on oat grain yield, yield components, grain quality, observed lodging, and plant traits that contribute to root lodging resistance. Row spacing and seeding depth were tested in three oat cultivars across two environments in Ontario, Canada. Seeding rate and the application of the plant growth regulator trinexapac‐ethyl (TE) at different nitrogen (N) fertilizer rates were tested in two‐to‐three oat cultivars across four environments. Lodging occurred naturally in all environments, with root lodging always occurring, sometimes in combination with stem lodging. Under high lodging pressure, shallow seeding increased lodging. Similarly, lodging increased with greater seeding rates when lodging pressure was high. Reducing row spacing had no effect on lodging but was the only management practice to consistently increase grain yield. TE reduced lodging in some environments, especially as N rates increased. Root plate spread, root plate depth, and root safety factor were minimally affected by the management practices studied and had complex interactions with genotype and environment. Among the measured crop traits, plant height had the strongest and most consistent relationship to observed lodging. Core Ideas: Management effects on lodging depended on whether lodging occurs before or after physiological maturity.Root plate spread and depth was more strongly affected by environment than management.Plant height was consistently related to lodging both before and after physiological maturity. [ABSTRACT FROM AUTHOR]

Vegetative phase change is a key trait in plant development and marks the transition from juvenile to adult growth phases. In maize (Zea mays L.), juvenile plants and plants with a late phase change can be identified by the increased production of tillers, aerial roots, and distinctive epicuticular wax. Resistance to agronomically significant pathogens can also differ between juvenile and adult plants. Using last leaf with juvenile wax as the target of selection, the maize population Minnesota 11 underwent 16 cycles of divergent selection. The objectives of this research were to identify emergent trends for each trait and to determine the magnitude and direction of phenotypic changes over long‐term selection compared to the source population. Phenotypic data on plant architecture traits, ear traits, and common rust resistance were collected in 2020 and 2021 by concurrently growing plants from selection cycles representing both directions of selection. Last leaf with juvenile wax, the direct target of selection increased to leaf 17.8 in the late phase change population and decreased to leaf 5 in the early phase change population from leaf 9 in the source population. Late vegetative phase change was positively correlated with increased common rust infection and plant height, and negatively correlated with ear size traits. This study shows that the observed phenotypic changes follow patterns of genetic variation consistent with divergent selection, but with possible effects of inbreeding. Core Ideas: Divergent recurrent selection is effective for manipulating vegetative phase change.Late vegetative phase change increases common rust susceptibility in maize.In the divergently selected populations, the limits of selection for vegetative phase have not been reached. [ABSTRACT FROM AUTHOR]

This work evaluated the efficiency of different genomic prediction (GP) methods in a diverse Mesoamerican panel of 339 common bean accessions, genotyped with 3398 SNP markers. Field experiments were carried out for three consecutive years, with adequate water supply (non‐stress—NS) and water restriction imposition (water‐stress—WS), analyzing seed weight (SW) and grain yield (GY). Two methods to predict the accuracies (rĝg) were adopted (GBLUP and Bayes) and also considered the environmental variation (GBLUP‐based reaction norm model). Similar accuracies were observed for both methods. For GY, the highest rĝg were detected under NS (rĝg = 0.49) in 2016 (rĝg = 0.49) and in the joint analysis for the WS condition (rĝg = 0.33), both for models using local landraces. For SW under NS, the rĝg was higher for the elite lines (rĝg = 0.72), whereas for WS, the rĝg dropped considerably, ranging from 0.45 to 0.61 for the joint analysis, considering the landraces and all samples, respectively. For GY and SW, under NS, the rĝg using both models increased with increasing number of SNPs, until reaching a plateau of 800 and 300 SNPs, respectively. Increasing the training population (TP) size resulted in greater accuracy. Taking in account the Genotype × Environment, the multienvironment model performed better especially for more complex traits (GY/NS: rĝg = 0.32). The GP approach has great potential to help commercial bean breeding programs improving the performance of target quantitative traits. Core Ideas: The GS methods evaluated (GBLUP and Bayes) showed similar prediction accuracies for components of productivity.Increased prediction ability was attributed to increasing training set size more than the increased marker density.Germplasm resources were successfully used to develop genomic prediction model to the breeding program.The landrace genetic diversity is a valuable resource to be explored through GS to design novel breeding programs.The genomic prediction approach has a great potential to assist breeding programs in improving quantitative traits. [ABSTRACT FROM AUTHOR]

Wheat (Triticum spp. L) production needs to be improved to meet the needs of a global population of >9 billion people by 2050. Increasing the productivity of the crop under conditions of abiotic and biotic stress to achieve food security continues to be a challenging proposition. Wheat stem sawfly (WSS) (Cephus cinctus Norton) has been considered as a serious pest of wheat since the late 19th century, causing devastating losses of wheat productivity in the Northern Great Plains of United States and regions of Canada. Developing resistant varieties of wheat that show consistent agronomic performances in varying environments is an effective strategy to manage WSS infestations. To achieve this goal, it is necessary to understand the underlying mechanisms of WSS infestation, damage, subsequent response of the host plant, and resulting yield losses. The review focuses on genetics, breeding, and development of solid stem (SS)‐mediated WSS resistance in wheat since it has been the most effective method of genetic resistance in reducing wheat yield losses. Furthermore, the knowledge gaps that need to be addressed to develop an effective resistant cultivar against WSS are also discussed. Core Ideas: Wheat stem sawfly is a major problem with no insecticide control mechanism.Solid stem varieties have been employed for wheat stem sawfly resistance.The review focused on providing comprehensive information on solid stem genetics, breeding, and development. [ABSTRACT FROM AUTHOR]

Some wild relatives have higher grain zinc (Zn) concentrations than common wheat and were widely used for wheat biofortification. However, little is known about the mechanisms controlling Zn accumulation in wheat and its wild relatives. This study is aimed to shed light on the causes of different grain Zn concentrations in wheat at a physiological level. Six genotypes, including one Triticale, one Triticum monococcum, one Triticum petropavlovskyi, and three Triticum aestivum, with different grain Zn concentrations, were evaluated in this study. Zn concentrations in roots and aboveground tissues in the field at grain maturity were measured to assess the differences in Zn uptake and partitioning among genotypes. Zn concentrations in roots and shoots at the seedling stage in hydroponics were also assessed to see if the differences in Zn uptake efficiencies could be identified before planting in the laboratory. The triticale had the highest grain Zn concentration, followed by the cultivated einkorn wheat, the T. petropavlovskyi wheat, and then the three common wheat varieties. No difference in Zn concentration was detected between grains from the main stem and grains from tillers. Genotypes with high grain Zn concentration generally had higher Zn uptake and rachis Zn loading efficiencies. The cultivated einkorn wheat showed retarded translocation of Zn in nodes. Genotypes with high Zn uptake efficiencies may be identified at the seedling stage in hydroponics. Grain Zn concentration is a product of multiple physiological processes. Roots, nodes, and rachis could be the potential target tissues for further research related to grain Zn accumulation. [ABSTRACT FROM AUTHOR]

Determining the stability and consistency of grain yield performance requires accurate evaluation of genotypes in different environments. In Mexico, annual national spring wheat irrigated trials (ENTRI) are conducted to assess elite bread (Triticum aestivum L.) and durum (Triticum durum L.) wheat performance in different testing environments (TEs) in the main wheat‐growing areas. These trials provide data supporting release of new cultivars and aim to also address Mexican wheat value chain grain needs. This study analyzed grain yield performance of 30 bread and durum wheat cultivars grown in trials in the 2012–2013 and 2013–2014 growing cycles conducted across TEs in northwest, north, and central Mexico. Environmental variability (location, sowing timing, and irrigation schemes) across the ENTRI enabled genotype by environment interaction to be effectively evaluated. Bread and durum wheat genotypes with high and stable grain yield were also identified and compared across TEs of the wheat‐growing areas of Mexico. The bread wheat cultivars Bacorehuis F2015 and Borlaug100 F2014, and the durum cultivars Barobampo C2015, CONASIST C2015, and Anatoly C2011 were high yielding and gave stable performance in most of the TEs. This analysis demonstrates the utility of multi‐year, multi‐environment testing and analysis to identify improved wheat cultivars to meet wheat production demand in Mexico. It also provides useful testing and analysis methods for selection of suitable broadly as well as locally adapted varieties in other wheat producing regions of the world. Core Ideas: We identified cultivars with high and stable grain yield in Mexico.Environmental variability enabled G × E interaction to be effectively evaluated.Multi‐year, multi‐environment testing and analysis is useful to identify improved wheat cultivars. [ABSTRACT FROM AUTHOR]

Applying cover crops to reduce nitrogen (N) fertilizer application while ensuring crop productivity is a major challenge for sustainable agricultural production. However, few studies have quantified N fertilizer application reduction through the use of February orchid (Orychophragmus violaceus) cover crops with the goal of ensuring cotton productivity. We conducted field experiments in the Yellow River basin on two cropping systems, monoculture cotton (Gossypium hirsutum L) and cotton/February orchid under four levels of N application (0 [N0], 112.5 [N1], 168.75 [N2], and 225 [N3] kg N·ha−1), to evaluate the impacts of cover cropping on cotton growth parameters, yield, and quality under different N application levels. The results indicated that replacing winter fallow with February orchid prolonged the cotton growth period and increased plant height, leaf area index (LAI), and dry matter accumulation but did not improve cotton yield or fiber quality. The Cotton/February orchid system under a 168.75 kg ha−1 N application rate improved cotton growth, and achieved yield and quality equivalent to those of monoculture cotton under a 225 kg ha−1 N application. Further analysis revealed that February orchid cover crop and N application positively affected lint yield, whereas plant height, LAI, and dry matter accumulation (positively) and phenology (negatively) predicted lint yield and fiber quality. In conclusion, cotton relay intercropping with February orchid in combination with 168.75 kg ha−1 N application is recommended as a suitable cropping system to reduce fallow fields and ensuring cotton productivity in the Yellow River basin and other areas with similar ecological conditions. Core Ideas: Replacing winter fallowing of fields with February orchid cultivation improved cotton growth parameters.Improvement in cotton growth and productivity with increasing nitrogen application rates.Relationships among cotton phenology, agronomic traits, yield, and quality were quantified.February orchid combined with 75% N fertilizer ensured cotton biomass and yield. [ABSTRACT FROM AUTHOR]

As a warm‐season turfgrass, bermudagrass (Cynodon) is sensitive to low ambient temperature. The objectives of this study were to evaluate cold tolerance of a new variant Chuannong‐3 under field condition and to further elucidate metabolic and molecular bases of cold tolerance in the Chuannong‐3 as compared to triploid Tifdwarf (Cynodon transvaalensis × Cynodon dactylon) and tetraploid common bermudagrass 001 (C. dactylon). The Chuannong‐3 was identified as a triploid bermudagrass based on ploidy analysis. Chuannong‐3, Tifdwarf, or common bermudagrass 001 exhibited different tolerance to low temperature in field (Chuannong‐3 > common bermudagrass 001 > Tifdwarf). The Chuannong‐3 maintained significantly lower oxidative damage to cell membrane system, chlorophyll loss, and inhibition of photochemical efficiency as well as higher water‐soluble carbohydrate content than Tifdwarf or common bermudagrass 001 in winter of 2022 and 2021. Further study found that Chunanong‐3 exhibited the highest glucose, fructose, sucrose, raffinose content, raffinose synthase activity, and CdSPS1 expression as compared to Tifdwarf and common bermudagrass 001, which provided potential protection against chilling and freezing damages. Chilling and freezing stresses significantly up‐regulated ABA‐dependent (endogenous ABA level, CdABF1, CdDHN4, and CdLEA3) and ABA‐independent (CdWRKY2, CdCBF1, and CdCOR440) pathways in three bermudagrasses, but the most pronounced effects were detected in the Chuannong‐3. These findings indicated that Chuannong‐3 had better ability to acclimate to low temperature stress in relation to up‐regulation of sugar accumulation and metabolism, ABA signaling, and CBF‐COR pathway. This new variant Chuannong‐3 could be a valuable bermudagrass grown in temperate and transition zones. Core Ideas: New bermudagrass variant Chuannong‐3 has dwarf phenotype and strong cold tolerance.Chuannong‐3 is identified as a triploid bermudagrass based on ploidy analysis.Chuannong‐3, common bermudagrass 001, or Tifdwarf is classified as a cold‐tolerant, medium, or sensitive genotype.Chunanong‐3 exhibits strong tolerance to low temperature associated with enhanced sugar metabolism.Chunanong‐3 has strong cold tolerance related to up‐regulation of ABA and CBF pathways. [ABSTRACT FROM AUTHOR]

Accelerating the rate of genetic gain of major crops is required to meet the projected global demand for food. Genomic selection (GS) has made valuable contributions to the genetic progress of different species and is currently a routine procedure in most wheat (Triticum aestivum L.) breeding programs (WBP). Accounting for gene × gene (G × G) and genotype × environment interactions (G × E) in GS can significantly enhance genetic improvement by increasing the rate of genetic gain and adaptation of wheat cultivars. However, a comprehensive and updated knowledge of G × G and G × E methodologies is required to define the appropriate breeding strategy. In this review, we start by briefly describing the current situation and relevance of wheat breeding, then we focus on the central concepts of G × G and G × E and discuss the implications, challenges, and opportunities for the implementation of interactions in GS and wheat breeding. This review is primarily intended to be a reference material for wheat breeders and researchers. Nevertheless, most of the concepts exposed are transferable to any other autogamous or clonal crops, and are therefore useful in a much broader scope. We expect to encourage and facilitate the implementation of GS models accounting for interactions in plant breeding. Core Ideas: Gene × gene and genotype × environment interactions are significant genetic components of complex traits.Nonadditive genetic effects can be exploited to improve genomic prediction and cultivar development.Modeling genotype × environment interactions is essential to develop cultivars well adapted to production systems.Microenvironmental sensitivity of cultivars can be exploited to improve crop resilience. [ABSTRACT FROM AUTHOR]

An understanding of the heterotic pattern in the active germplasm is the first and crucial step in any hybrid breeding program. Diallel and line × tester (L × T) mating designs were extensively followed to understand the heterotic pattern based on the combining ability information. The present study adopted GGE biplots, generated using the L × T matrix to understand the tropical maize germplasm's heterotic pattern and identify the best tester combinations for heterotic grouping. The L × T matrix and combining ability information was generated by evaluating 985 testcross, generated by crossing 110 diverse tropical inbred lines with 10 inbred testers at two geographically diverse locations. The stability of combining ability effects, the magnitude and direction of combining ability effects, and also the discrimination and representativeness of testers were considered for the identification of best tester combinations for heterotic grouping. The present investigation has shown the usefulness of GGE biplots' effectiveness in understanding the heterotic pattern and identifying the best tester combinations for heterotic grouping. The results of the present investigation revealed the existing heterotic pattern in the elite tropical maize inbred lines that were extensively used in hybrid maize breeding. The findings of the present study are of immense practical significance, which not only guides different hybrid maize breeding programs but also helps to identify the best testers in their respective hybrid breeding programs. The study showed that the GGE biplot method can be adopted to understand the active germplasm's heterotic pattern and organize the germplasm into different heterotic groups. Core Ideas: Heterotic grouping using GGE biplot.Identification of best tester for heterotic grouping.Visualization of combining ability information in GGE biplot.Effectiveness of combining ability information for heterotic grouping methods.Identification of heterotic pattern in active germplasm. [ABSTRACT FROM AUTHOR]

Climate change is threatening the status quo of agricultural production globally. Perennial cropping systems could be a useful strategy to adapt agriculture to a changing climate. Current and future perennial row crop systems have many and varied applications and these systems can respond differently than annuals to agricultural challenges resulting from climate change, such as shifting ranges of plant, pathogen, and animal species and more erratic weather patterns. To capitalize on attributes of perennial systems that assist in our ability to adapt to a changing world, it is important we fully consider the component parts of agroecosystems and their interactions, including species, genotype and genotypic variance, environment and environmental variance, adaptive management strategies, and farm socioeconomics. We review the current state of perennial grain and oilseed crops for integration into row crop agriculture and summarize the potential for current and future systems to support multiple environmental benefits and adaptation to climate change. We then propose a plant breeding strategy that incorporates the complexity of common domestication traits as they relate to future perennial crop improvement and adaptation and highlight digital technologies that can advance these goals. Evaluation of genetic gain during the development of new perennial crops and systems can be improved using research designs that span an environmental gradient that captures the forecasted shift in climate for a region, which we demonstrate by reanalyzing existing data. Successful development and deployment of perennial crops as a climate adaptation strategy depends on grower adoption, scalability, and sustainable modifications to markets and supply chains. Core Ideas: Many agronomic and horticultural crops are perennials, which survive for years or decades after establishment.Perennial crops are uniquely positioned to reduce the impacts of changing climates on growers.Perennial crops are uniquely positioned to increase the ecological and social benefits of agriculture.Perennial grain and oilseeds must be able to withstand increasingly erratic weather and shifts in disease, weed, and pest pressures.Perennial grains and oilseed crops will play a more important role in sustainable and profitable agricultural production in the future. [ABSTRACT FROM AUTHOR]