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Writing and Presenting Scientific Papers. B. MALMFORS, P. GARNSWORTHY, and M. GROSSMAN. Nottingham University Press, Nottingham NG11 OAX, United Kingdom. 2001. Paperback, 133 pp., 15.00 £. ISBN 1-897676-92-1. The aim [...]

Writing and Presenting Scientific Papers (2nd edition). B. Malmfors, P. Garnsworthy, and M. Grossman. Nottingham University Press, Manor Farm, Main Street, Thrumpton, Nottingham NG11 0AX, UK. Available from Blackwell Publishing, [...]

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]

This article is part of a series of brief commentaries to highlight papers that have resulted in important and distinctly new perspectives in crop science. A criterion for selection of papers is that they must have been published at least 20 yr ago to allow for a long‐range perspective in assessment of the papers. The current article briefly reviews the paper by C.T. de Wit published in 1958 that explored the relationship between transpiration and crop growth. He organized his analysis data from experiments from a range of environments, many of which were done early in the 20th century. He found that there was a very high correlation within a species between growth and transpiration normalized for pan evaporation over a wide range of conditions, and the slope of the relationship was distinct for each species. He examined possible variation in the slope to growth conditions and found the slope remained essentially constant. Thus, he concluded that there was an intimate, stable dependence for each crop species on the amount of water lost and its growth. [ABSTRACT FROM AUTHOR]

This article is part of a series of brief commentaries to highlight papers that have resulted in important and distinctly new perspectives in crop science. A criterion for selection of papers is that they must have been published at least 20 yr ago to allow for a long‐range perspective in assessment of the papers. The current article briefly reviews the paper by Harold L. Penman published in 1948 that offered an original analysis of approaches to estimate evaporation from natural surfaces. He developed two approaches: one based on a sink strength model, and the second on an energy balance model. He compared the predictions of these approaches to his experimental observations of evaporation from open water, bare soil, and grass. He found each of the models did well (r ≈ 0.8) in predicting open water evaporation. The evaporation from bare soil and grass was less than that from the open water, and the predicted evaporation amounts were variable even when normalized by open water evaporation. Even though Penman warned that aspects of the approaches were empirical, the energy balance model remains a mainstay in predicting crop water loss. [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]

The article focuses on the Yearly Reports of the Crop Science Society of America (CSSA). It lists former presidents of the CSSA which include G.O. Mott, Mark Brick and D.D. Baltensperger. It highlights Director of Publications Report which predicts that the Digital Library will generate subscription over one million in both member and non-member category and mentions a graph showing total number of pages published in the journal from 1994-2014.

This article is part of a series of brief commentaries to highlight papers that have resulted in important and distinctly new perspectives in crop science. A criterion for the selection of papers is that they must have been published at least 20 yr ago to allow for a long-range perspective in assessment of the papers. The current article briefly reviews the paper by George Robertson published in 1968 that provided key concepts used yet today to describe the pace of plant development. Robertson developed the ideas of normalized development rates for each ontogenetic stage, multiplication of temperature and photoperiod responses, and inclusion of base temperature and photoperiod parameters in the response functions. [ABSTRACT FROM AUTHOR]

This article is part of a series of brief commentaries to highlight papers that have resulted in important and distinctly new perspectives in crop science. A criterion for selection of papers is that they must have been published at least 20 yr ago to allow for a long‐range perspective in assessment of the papers. The current article briefly reviews the paper by M. Wayne Adams published in 1967 that provided original insights about compensation in the components of seed number and seed yield in determining crop yield. Adams reviewed experimental results in a large number of crop species and discovered a consistent negative correlation between seed number and mean seed mass. He labeled this negative correlation as "component compensation" in the formation of yield. He hypothesized that component compensation resulted from limiting nutrient‐metabolite availability to support developing reproductive structures. Ultimately, the retained seeds would be filled to the extent allowed by the supply of nutrient‐metabolites so that there was compensation between seed number and individual seed mass. [ABSTRACT FROM AUTHOR]

This article is part of a series of brief commentaries to highlight papers that have resulted in important and distinctly new perspectives in crop science. A criterion for selection of papers is that they must have been published at least 20 yr ago to allow for a long‐range perspective in assessment of the papers. The current article briefly reviews the paper by C.M. Donald and J. Hamblin published in 1976 that provided original insights about the role of harvest index (defined by them as the ratio of economic yield to aboveground mass) in influencing crop yield. Donald and Hamblin reviewed experimental results showing that harvest index was relatively stable across variations in plant size, had high heritability, and was associated with high grain yield. Although their observations were confirmed in subsequent tests, inconsistent results in plant selection in breeding programs for high yield based on harvest index has discouraged the use of harvest index as a basis for selection. Nevertheless, high harvest index is now well ingrained as an essential plant characteristic for high crop yields. [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]

This article is part of a series of brief commentaries to highlight papers that have resulted in important and distinctly new perspectives in crop science. A criterion for selection of papers is that they must have been published at least 20 yr ago to allow for a long-range perspective in assessment of the papers. The current article briefly reviews the paper by W.G. Duncan, R.S. Loomis, W.A. Williams, and R. Hanau published in 1967 that provided original concepts about the interception of solar radiation by crop leaf canopies and the estimate of canopy photosynthesis rate based on the intercepted radiation. They developed a geometric description of beam penetration through leaf layers and calculation of canopy CO2 exchange by considering separately leaves in direct-beam radiation and in the shade. [ABSTRACT FROM AUTHOR]

This paper presents an extension to a heuristic method for phasing and imputation of genotypes of descendants in biparental populations so that it can phase and impute genotypes of parents that are ungenotyped or partially genotyped. The imputed genotypes of the parent are used to impute low‐density (Ld) genotyped descendants to high density (Hd). The extension was implemented as part of the AlphaPlantImpute software and works in three steps. First, it identifies whether a parent has no or Ld genotypes and identifies its relatives that have Hd genotypes. Second, using the Hd genotypes of relatives, it determines whether the parent is homozygous or heterozygous for a given locus. Third, it phases heterozygous positions of the parent by matching haplotypes to its relatives. We measured the accuracy (correlation between true and imputed genotypes) of imputing parent genotypes in simulated biparental populations from different scenarios. We tested the imputation accuracy of the missing parent's descendants using the true genotype of the parent and compared this with using the imputed genotypes of the parent. Across all scenarios, the imputation accuracy of a parent was >0.98 and did not drop below ∼0.96. The imputation accuracy of a parent was always higher when it was inbred than outbred. Including ancestors of the parent at Hd, increasing the number of crosses and the number of Hd descendants increased the imputation accuracy. The high imputation accuracy achieved for the parent translated to little or no impact on the imputation accuracy of its descendants. Core Ideas: Hd SNP data in plant breeding populations is increasingly valuable for genomic selection.Hd genotyping thousands of candidates is expensive, imputation is a cost‐effective alternative.This paper presents an extension to a heuristic method for phasing and imputation of genotypes.Across all scenarios, imputation accuracy of a parent was >0.98 and did not drop below ∼0.96.High imputation accuracy for the parent translated to no impact on offspring imputation. [ABSTRACT FROM AUTHOR]

This article is part of a series of brief commentaries to highlight papers that have resulted in important and distinctly new perspectives in crop science. A criterion for selection of papers is that they must have been published at least 20 yr ago to allow for a long‐range perspective in assessment of the papers. The current article briefly reviews the paper by M.Y. Siddiqi, A.D.M. Glass, T.J. Ruth, and T.W. Rufty, Jr. published in 1990 that investigated the kinetics of nitrate influx by barley (Hordeum vulgare L.) seedlings. Using 13NO3−, they documented the existence of two influx systems. One was inducible and nitrate influx saturated under low nitrate concentrations. The second was noninducible and expressed a linear increase in nitrate influx over high nitrate concentrations. Key transformative results from this study were the demonstration that both systems were under negative feedback control based on root nitrate concentration. [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 article presents the yearly reports of the Crop Science Society of America (CSSA). It mentions the presidents of the CSSA from 1956 to 2011 including G. O. Mott, C. W. Stuber, and M. Gallo. It states that the journal "Crop Science" (CS) has published more pages in 2011 by nearly 100 and its impact factor rose by 2.020 in 2011. Meanwhile, the expenses and revenues of CS until August 2011 have performed closely to the budget with slightly higher publication expenses in 2012 than in 2011.

This article is part of a series of brief commentaries to highlight papers that have resulted in important and distinctly new perspectives in crop science. A criterion for selection of papers is that they must have been published at least 20 yr ago to allow for a long‐range perspective in assessment of the papers. The current article briefly reviews the paper by H.D. Cooper and D.T. Clarkson published in 1989 that offered an original analysis of internal movement of nitrogen in wheat (Triticum aestivum L.). Using 15NO3− fed to a split‐root system, they found that a large fraction of absorbed nitrogen was rapidly cycled around the plant as a result of exchanges between the xylem and phloem. They concluded that cycling in the plant ensured tissues had access to a common pool of soluble nitrogen from which nitrogen could be removed and incorporated into protein depending on the demands of tissue growth. The cycling pool of nitrogen also provided a possible whole‐plant signaling mechanism that coordinates growth activities with the feedback control system regulating nitrate uptake by the root. [ABSTRACT FROM AUTHOR]

This article is part of a series of brief commentaries to highlight papers that have resulted in important and distinctly new perspectives in crop science. A criterion for selection of papers is that they must have been published at least 20 yr ago to allow for a long‐range perspective in assessment of the papers. The current article briefly reviews the paper by J.T. Ritchie published in 1981 that explored the use of extractable soil water as an independent variable for defining plant response to water deficit conditions. Recognizing the difficulty of using leaf water potential in defining plant response, he proposed an independent variable based on volumetric soil water content. Specifically, plant response was based on extractable soil water described as a function of 'fraction of total extractable water in the root zone.' Ritchie proposed a template for sensitivity of plant processes to soil drying based on fraction of total extractable water. Response functions based on this template have now been extensively studied and are key parts of many approaches to describing water use in both experimental and modeling studies. [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]

Homeowners typically use commercial "patch and repair" products to seed bare or damaged lawn areas in the spring. Commercial products typically contain inert matter, fertilizer, and turfgrass seed, which is dominated by perennial ryegrass (Lolium perenne L.) and tall fescue [Festuca arundinacea Schreb.; syn. Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.] mixtures, with a few fine fescues (Festuca spp.). Our objective was to assess the establishment potential of low‐cost patch and repair ingredients in the spring that include low‐input fine fescues. Field experiments were initiated in Indiana and Oregon in April 2019 to investigate seven mulch ingredient treatments and two starter fertilizer treatments. All treatments included the same fine fescue seed mixture. All mulch ingredients, including the untreated (no mulch) control, eventually reached a similar turf cover; however, the rate of establishment was influenced by the mulch ingredient. Conversely, starter fertilizer had a minimal impact on the establishment rates but increased final turf cover. Compost‐derived mulch consistently resulted in faster turf establishment, which was generally ≥6 d sooner than other mulch options, with the exception of potting soil, no mulch, and, at times, topsoil, which may provide similar results. The results indicate if the newly seeded area is adequately irrigated, then neither mulch ingredient nor starter fertilizer may be necessary, thus providing more financial savings for consumers. The results also indicate there are multiple financially feasible options for homemade patch and repair ingredients for homeowners and lawn professionals to use in the establishment of low‐input turfgrasses from seed. [ABSTRACT FROM AUTHOR]

Use of resistant cultivars is one of the most important measures to reduce the risk of Fusarium head blight (FHB, caused by various Fusarium spp.) and mycotoxins in cereals. Research on resistance to FHB has mainly focused on wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) and is very limited in oat (Avena sativa L.). In Norway, routine testing of cultivars and breeding lines has been performed in spawn-inoculated field experiments with Fusarium graminearum Schwabe as part of a concerted research and breeding effort to improve FHB resistance in oat. Data on FHB symptom, days to flowering, and plant height have been collected during the field seasons. Together with the field data, deoxynivalenol (DON) content and germination capacity of harvested kernels are used to score resistance levels of genotypes. In this paper, results are presented from a combined analysis of data from 9 yr of field trials from 2008 to 2016. Consistent and highly significant differences in DON content and germination capacity were documented among the current oat cultivars on the Norwegian market. These two negatively correlated parameters are used as selection criteria in breeding since they are relevant for the different end uses of the grains: DON content for use as food and feed, and germination capacity for seed production. In the paper, we discuss the pros and cons of the various screening methods and parameters used in assessing FHB resistance in oat and present the progress made in resistance breeding based on an established field testing methodology. [ABSTRACT FROM AUTHOR]

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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]

This article is part of a series of brief commentaries to highlight papers that have resulted in important and distinctly new perspectives in crop science. Here, we outline a series of two papers by French and Schultz (F&S) on water use efficiency of wheat (Triticum aestivum L.) published in 1984. The insight of F&S was not to draw a regression line across their yield‐evapotranspiration data. Instead they saw an upper limit of 20 kg ha−1 mm−1 that, less than a decade after publication, was widely used by Australian farmers to benchmark their crops and identify causes of yield gaps. Over the last two decades, F&S‐type benchmarks have been expanded beyond wheat and beyond Australia to include sunflower (Helianthus annuus L.) in Argentina, maize (Zea mays L.) and wheat in the United States and China, and millet [Pennisetum glaucum (L.) R. Br.] in West Africa, among others. More recently, the concept of yield gap analysis based on a upper limit of yield per unit resource uptake has been successfully extrapolated to N. The N uptake per millimeter of water required to meet the water‐limited yield potential (0.65 kg N ha−1 mm−1 under their original conditions) is a hidden insight in the work of French and Schultz; it has been recently rediscovered in the context of crop improvement, co‐limitation theory, and drought‐induced N deficit. Perhaps more deeply, French and Schultz shifted farmers mindset from the mildly fatalistic idea of "drought" to the notion that many other factors were typically limiting crop yield, and the quantitative challenge of attaining a plausible benchmark. [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]

The article focuses on Crop Science Society of America (CSSA's) yearly reports. Topics include Executive Committee Meetings and CSSA Board of Directors meetings; 2018 CSSA divisions, branches, and committees; and contacts of headquarters' staff including Managing Editor Matt Nilsson and Science Editor Tracy Hmielowski.

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]

Wheat is a staple crop in Nepal and is the third major cereal crop grown across the country. To improve productivity and increase the number of farmers growing wheat, the Nepal Agricultural Research Council (NARC), since 1962, has been releasing new wheat varieties with higher productivity and disease resistance. Accurate identification of the varieties grown in farmer's fields is critical for assessing the adoption levels and the impact of new varieties. This understanding can change the landscape of the wheat market and the overall vulnerability of the crop to diseases and abiotic stresses. Current methods of identification that rely on farmer description and morphological traits have been associated with ambiguity. The objective of this study was to determine the varietal adoption of wheat in the seven wheat‐growing provinces of Nepal using DNA fingerprinting technology. The study revealed that 'Gautam' and 'Vijay' are the most popular wheat varieties planted in the plain areas of Nepal. The area covered in these varieties during the 2018–2019 wheat season was 20.3 and 19.5% respectively. 'WK1204' was popular and mostly planted in the mountainous areas of Nepal during the October–May cropping season. The decommissioned varieties, including 'Lerma Roja‐64', 'Pitic62', 'Kalyansona', 'NL‐30', 'Siddhartha', 'Vaskar', 'Vinayak', 'Annapurna‐2', and 'NL 251' are still in use by 8% of wheat farmers across Nepal. Almost 38% of the varieties currently grown were released 20 yr ago. The varietal adoption was determined using molecular markers through fingerprinting, and its implications are discussed in this paper. Core Ideas: Accurate understanding of varietal adoption is critical for its dissemination and helps frame effective agricultural policies that benefit farmers and consumers.Accurate identification of the varieties in farmer fields is critical for assessing impact.DNA fingerprinting of wheat varieties is a reliable method to asses variety adoption. [ABSTRACT FROM AUTHOR]

Genomic selection can increase the rate of genetic gain in plant breeding programs by shortening the breeding cycle. Gain can also be increased through higher selection intensities, as the size of the population available for selection can be increased by predicting performance of nonphenotyped, but genotyped, lines. This paper demonstrates the application of genomic prediction in a sorghum [Sorghum bicolor (L.) Moench] breeding program and compares different genomic prediction models incorporating relationship information derived from molecular markers and pedigree information. In cross-validation, the models using marker-based relationships had higher selection accuracy than the selection accuracy for models that used pedigree-based relationships. It was demonstrated that genotypes that have not been included in the trials could be predicted quite accurately using marker information alone. The accuracy of prediction declined as the genomic relationship of the predicted individual to the training population declined. We also demonstrate that the accuracy of genomic breeding values from the prediction error variance derived from the mixed model equations is a useful indicator of the accuracy of prediction. This will be useful to plant breeders, as the accuracy of the genomic predictions can be assessed with confidence before phenotypes are available. Four distinct environments were studied and shown to perform very differently with respect to the accuracy of predictions and the composition of estimated breeding values. This paper shows that there is considerable potential for sorghum breeding programs to benefit from the implementation of genomic 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 article offers information on miscellaneous topics related to the annual report of the Crop Science Society of America (CSSA). Topics discussed include list of presidents for CSSA include G.H. Heichel, Mark Brick and H.L. Shands; evaluation of the "Journal of Environmental Quality" (JEQ); and appointment of Ed Gregorich as the editor of JEQ.

This paper is concerned with the generation of designs for early generation, plant‐breeding experiments that use limited experimental resources as efficiently as possible to maximize the realized genetic gain (RGG) resulting from the selection of lines. A number of authors have demonstrated that partially replicated (p‐rep) designs for such experiments, in which the percentage of lines that are duplicated is p, are likely to be more efficient than grid‐plot designs. Therefore, our aim is to obtain the most efficient p‐rep design for an experiment using one of two distinctly different criteria and employing widely or readily available statistical software packages to search for an optimal design. However, this can be difficult because knowledge of the sources of variation and their magnitudes is required and is often unavailable. To overcome this impediment, a comprehensive simulation experiment was conducted to investigate whether designs that are robust to a wide range of experimental situations can be identified. Designs with p set to 20% and for different experimental situations are generated and the performance of each tested for 24 different variation scenarios. We concluded that for large experiments, the RGG obtained with various optimal designs is indeed not affected by the different variation scenarios and that resolved designs for fixed genetic effects should be generated for robustness. On the other hand, the design assumptions affect the RGG for small p‐rep designs. Even so, an overall recommendation is made. [ABSTRACT FROM AUTHOR]

The popularity of Tartary buckwheat [Fagopyrum tataricum (L.) Gaertn], as a medicinal and food crop, has been increasing in recent years. However, its low yield seriously restricts its industrial development. Amongst the various studies conducted to enhance the productivity of Tartary buckwheat, the association between yield and main agronomic traits has formed the foundation for the breeding and cultivation of high‐yielding varieties, becoming the primary interest of breeders. The commonly used methods are often restricted by sample size, distribution assumptions and trait properties and confined to the linear relationship. In this paper, the random forest regression model was used to obtain a comprehensive and reliable evaluation. The phenotypic data of 200 Tartary buckwheat landraces with 15 quantitative and two qualitative agronomic traits for two consecutive years were used. Results were compared between planting seasons and with those from classical methods, such as the correlation analyses and the multiple linear regression model. The random forest model distinguished the number of grains per plant, plant height, and 1,000‐grain weight as the most influential agronomic traits in both seasons. The main and interactive effects were explored using the accumulated local effects plot and showed great conformity between the two seasons. The robustness and reliability of the random forest model make it a desirable methodology for breeding new varieties and germplasm innovation of Tartary buckwheat and other crops. [ABSTRACT FROM AUTHOR]

This paper reports a first study exploring genomic prediction for adaptation of sorghum [Sorghum bicolor (L.) Moench] to drought‐stress (D‐ET) and nonstress (W‐ET) environment types. The objective was to evaluate the impact of both modeling genotype × environment interaction (G×E) and accounting for heterogeneous variances of marker effects on genomic prediction of parental breeding values for grain yield within and across environment types (ETs). For this aim, different genetic covariance structures and different weights for individual markers were investigated in best linear unbiased prediction (BLUP)‐based prediction models. The BLUP models used a kinship matrix combining pedigree and genomic information, termed K‐BLUP. The dataset comprised testcross yield performances under D‐ET and W‐ET as well as pedigree and genomic data. In general, modeling G×E increased predictive ability and reduced empirical bias of genomic predictions for broad adaptation across both ETs vs. models that ignored G×E by fitting a main genetic effect only. Genomic predictions for specific adaptation to D‐ET or W‐ET were also improved by K‐BLUP models that explicitly accommodated G×E and used data from both ETs relative to prediction models that used data from the targeted ET exclusively or models that used all the data but assumed no G×E. Allowing for heterogeneous marker variances through weighted K‐BLUP produced clear increments (43–72%) in predictive ability of genomic prediction for grain yield in all adaptation scenarios. We conclude that G×E as well as locus‐specific genetic variances should be accommodated in genomic prediction models to improve adaptability of sorghum to variable environmental conditions. [ABSTRACT FROM AUTHOR]