Relative Maturity Research Articles

Morphometric constraints on the formation of new terrestrial analogs for planetary pits

The origin of geological depressions abounding on Mars and other planetary bodies remains poorly understood, partially due to the limited variability in the geological settings of existing terrestrial analogs. Here, we present a new terrestrial analog that is located at the northwestern margin of the Levantine volcanic field of Harrat Ash−Shaam along the Dead Sea Transform. The analog site consists of tens of geological depressions (locally named “juba”) that morphologically resemble Martian bowl-shaped pits and occur within a Pleistocene basaltic plateau that overlies Meso-Cenozoic carbonates. To constrain plausible formation mechanisms for the juba depressions, we carried out detailed field mapping and morphometric analyses using a 0.25 m/pixel digital terrain model (DTM) derived from airborne light detection and ranging (LiDAR) survey covering 34 km2 of the study area, and centimeter-scale, ground-based LiDAR scans of selected juba depressions. We show that variable magnitudes of slope asymmetry between north- and south-facing walls within the juba depressions, along with different degrees of sediment infilling, provide effective proxies for the relative geomorphic maturity of these landforms, and in turn indicate asynchronous formation of the juba depressions after the Pleistocene emplacement of the Harrat Ash−Shaam basalts in the study area. Our findings preclude formation of the juba depressions by phreatomagmatic explosions and instead point toward collapse into missing subsurface volume. In a broader context, we propose that the morphometric analyses developed herein to distinguish between plausible juba formation mechanisms in the Harrat Ash−Shaam volcanic field can be extended to better constrain the formation mechanisms of similar pit features on Mars and other planetary bodies.

Registration of ‘S11‐16653C’ soybean: A high‐yielding conventional cultivar with broad resistance to diseases and nematodes

AbstractThe soybean [Glycine max (L.) Merr] line S11‐16653C (Reg. no. CV‐554, PI 700000) was developed and released as a cultivar by the University of Missouri, Fisher Delta Research, Extension, and Education Center (MU‐FDREEC). S11‐16653C is an early maturity group V (relative maturity 5.3), high‐yielding conventional (non‐genetically modified) cultivar with determinate growth habit. It is a chloride excluder and has a broad disease resistance package, including soybean cyst nematode (Heterodera glycines Ichinohe) races 1 (HG type 2.5.7), 2 (HG type 1.2.5.7), 3 (HG type 5.7), 5 (HG type 2.5.7), southern root‐knot nematode [Meloidogyne incognita (Kofold & White) Chitwood], peanut root‐knot nematode [Meloidogyne arenaria (Neal) Chitwood], reniform nematode (Rotylenchulus reniformis Linford & Oliveira), stem canker (Diaporthe aspalathi Jansen, Castlebury & Crous), Phytophthora root rot (caused by Phytophthora sojae M.J.Kaufmann & J.W.Gerdemann), and sudden death syndrome (Fusarium virguliforme O'Donell & T. Aoki). S11‐16653C was tested in 78 locations across nine states (Alabama, Arkansas, Kansas, Louisiana, Missouri, Mississippi, North Carolina, Tennessee, and Virginia) from 2012 to 2016. It was entered in internal yield tests at the MU‐FDREEC (2012–2014), USDA Uniform Soybean Tests (2014–2016), and soybean state variety tests (2015). It showed consistent high‐yielding performance and broad adaptability throughout the trials and locations. Overall, S11‐16653C is a high‐yielding conventional soybean cultivar that has potential for commercial production and serves as an exceptional germplasm for soybean breeding.

Researching social support on social networking sites: relevance and main challenges

The article outlines the current state of social support research on social networking sites (SNS), which is a broad category of online services, most prominent among which currently are Facebook, Instagram, Twitter, and TikTok, and reviews key problems that presently influence the sphere. In particular, it summarizes the patchwork of approaches to conceptualization and operationalization of the term “online social support” (social support on SNS) that is present in the extant literature on the subject, while pointing out the main challenges that have been complicating the efforts toward drawing clearer conceptual boundaries around this term. The article also extensively covers the issue of creating valid, culturally sensitive tools that measure online social support, mentioning factors related to both the limits of the existing tools and the environment that these tools are intended to measure. The peculiar nature of social networking platforms as a research environment is explained at length, including their constantly evolving state, substantial variability across different services, and the privacy and security considerations that affect which primary empirical data about the audience of social networks can be accessed by the researchers. Both the uniqueness of SNS as the medium for exchanging online social support and the importance of improving existing tools for gathering empirical data about the attitudes and behaviors of the sites’ users in order to achieve a more systematic and valid picture of online social support are substantiated. The solutions to the aforementioned problems are not the focus of this particular text. Instead, the overarching goal is to create a comprehensive examination of the issues that exist, the ways in which many of them are interlinked, and the reasons why many of them have not been resolved up to this point, despite relative maturity of the research field. This groundwork will hopefully make the search for solutions significantly more productive.

Relative growth and morphological sexual maturity of the crab Hepatus pudibundus (Herbst, 1785) (Decapoda: Aethridae) in southeast Brazil

ABSTRACT The crab Hepatus pudibundus is a bycatch of the shrimp fishing industry, and despite having no commercial value, it is impacted by fishing activities. In this way, research about relative growth and sexual maturity can help to understand the life cycle of fisheries-affected species. Thus, the present study aimed to estimate morphological sexual maturity (MSM) and analyse the relative growth of a population of H. pudibundus. For morphometric analysis and MSM estimate, the following structures were measured: the carapace (CW) and abdomen width (AW), the left and right cheliped propodus length (LPL and RPL) and height (LPH and RPH) for both sexes, and the gonopodium length (GL) for males. No heterochely was observed for both sexes, but the propodus dimensions showed sexual dimorphism. Males attain MSM at 44.71 mm CW and females at 41.87 mm CW. Males and females showed higher growth rates in GL and AW, respectively, in the juvenile stage, suggesting a greater investment in the development of secondary sexual characteristics before MSM. The present study provides information on the growth pattern of the species, which is significant to the community structure of fishing areas and serves as a parameter for evaluating protective measures that have been implemented.

REMATTOOL-R: a smart tool for identifying superior maize genotypes from multi-environment yield trials

ABSTRACT Breeders routinely evaluate many experimental hybrids that may be of different maturities. In maize (Zea mays L.), days to 50% anthesis and percent grain moisture content are used as proxies for relative maturity. The lack of an easy-to-use statistical tool that gives yield potential of all entries in a trial while classifying them into different relative maturity categories in a single visualization makes it difficult to quickly assess superior genotypes. We report on a tool called REMATTOOL-R to aid breeders in visualizing and assessing the relationship between yield and certain agronomic traits, viz., days to anthesis, percent harvest grain moisture content, and number of harvested plants, and help them in advancing experimental hybrids to the next stage. REMATTOOL-R uses either Best Linear Unbiased Estimators (BLUEs) or Best Linear Unbiased Predictors (BLUPs) of yield and agronomic traits from multilocation trials to perform various computations. The various computations produce graphical and tabular visualizations of the relationship between grain yield and days to anthesis, moisture content, and number of harvested plants that can be used to support selection decisions by the breeder. REMATTOOL-R output tables show entries with at least 5% higher yield than the check varieties in the trial. REMATTOOL-R is a robust, simple, user-friendly, and easily comprehensible tool, convenient for identifying superior genotypes during all the trial stages of a maize breeding program. REMATTOOL-R will be useful to breeders and researchers in related disciplines.

Exploring avenues for agricultural intensification: A case study for maize-soybean in the Southern US region

CONTEXTCrop intensification is a key aspect for achieving global food security and exploring options for optimizing land use and environmental resources. Following this rationale, a maize (Zea mays L.) – soybean (Glycine max L.) double cropping was tested to intensify current agricultural systems in the Southern region of the United States (US). OBJECTIVEThe aims of this study were to i) assess the feasibility of cultivating maize-soybean double crop in the Southern US, ii) explore the best scenario of maize-soybean crops integrating field data with APSIM crop growth model via calculation of the land equivalent ratio (LER), and iii) evaluate the risk of crop failure for each crop combination. METHODSFor this case study, one year field research and in-silico experiments using 30-years of weather data were analyzed to evaluate the different lengths of growth cycle for both crops for yield, LER, and percentage of success. The feasibility of the maize-soybean sequence was determined by increasing yield gain for the soybean crop while maintaining similar yield for maize crop. RESULTS AND CONCLUSIONSSimulated LER values ranged from 1.1 to 1.3 with the maize hybrid 110 comparative relative maturity followed by a soybean maturity group 3.0 as the best combination for maximum LER. Lastly, long-term simulations confirmed the low risk associated with maize-soybean double crop sequences across sowing dates. SIGNIFICANCEExpanding the implementation of this farming system could produce additional benefits not only on productivity and land use efficiency but in overall economic return for farmers in the Southern US region.

Understanding the Determinants of Blockchain Technology Adoption in the Construction Industry

Blockchain has great potential for facilitating the development of the construction industry but has not been widely used to this end. The objective of this study was to identify the factors affecting the adoption of blockchain in the construction industry from the technical, organizational, and environmental dimensions with the help of theories related to technology adoption. Empirical results showed that relative advantage, compatibility, competitive pressure, technological maturity, organizational readiness, and policy have an impact on intention to adopt blockchain in the construction industry through perceived usefulness or perceived ease of use. Competitive pressure has the greatest impact on the internal variables of the technology acceptance model (TAM) (0.696). Perceived cost of adoption does not have a significant effect on blockchain adoption behavior. However, in contrast to previous research, organizational readiness has a negative effect (−0.03) on perceived usefulness. The research results provide inspiration for further research on the impact mechanisms of blockchain adoption in the construction industry, as well as guidance for governments to formulate blockchain adoption policies and guidance for the widespread application of blockchain in construction.

Seed maturation and its practical implications

The use of high vigour seeds for crop production is increasing in importance. Seed vigour develops during the late maturation phase, after deposition of reserves and attainment of maximum dry weight. During this phase, various protective mechanisms are imposed in the seeds that will aid survival after release from the mother plant. These mechanisms include the production of protective metabolites such as antioxidants and pigments, specific proteins and degradation of chlorophyll. All are essential for maximum quality of seeds used as propagation material, since they aid in providing increased tolerance to diverse biotic and abiotic stresses. Physical sanitation treatments, ageing during storage and threat by pathogens are some of the stresses that the seeds can experience during production, processing and germination. However, harvesting seeds at the fully mature stage and with maximum vigour is a big challenge in seed production. For most seeds, analysis of chlorophyll levels can be used as a measure of relative maturity. This is a rather sensitive technique as it uses the fluorescence properties of chlorophyll, and can also be used for upgrading seed lots containing relatively large fractions of less mature seeds. Sorted seed fractions are also useful to study processes during late seed maturation and the different seed vigour aspects gained during late seed maturation.

Principles of the Battery Data Genome

<h2>Summary</h2> Batteries are central to modern society. They are no longer just a convenience but a critical enabler of the transition to a resilient, low-carbon economy. Battery development capabilities are provided by communities spanning materials discovery, battery chemistry and electrochemistry, cell and pack design, scale-up, manufacturing, and deployments. Despite their relative maturity, data-science practices among these diverse groups are far behind the state of the art in other fields, which have demonstrated an ability to significantly improve innovation and economic impact. The negative consequences of the present paradigm include incremental improvements but few breakthroughs, significant manufacturing uncertainties, and cascading investment risks that collectively slow deployments. The primary roadblock to a battery-data-science renaissance is the requirement for large amounts of high-quality data, which are not available in the current fragmented ecosystem. Here, we identify gaps and propose principles that enable the solution by building a robust community of data hubs with standardized practices and flexible sharing options that will seed advanced tools spanning innovation to deployment. Precedents are offered that demonstrate that both public good and immense economic gains will arise from sharing valuable battery data. The proposed Battery Data Genome looks to broadly transform innovations and revolutionize their translation from research to societal impact.

Mature and old-growth forests contribute to large-scale conservation targets in the conterminous United States

Mature and old-growth forests (MOG) of the conterminous United States collectively support exceptional levels of biodiversity but have declined substantially from logging and development. National-scale proposals to protect 30 and 50% of all lands and waters are useful in assessing MOG conservation targets given the precarious status of these forests. We present the first coast to coast spatially explicit MOG assessment based on three structural development measures—canopy height, canopy cover, and above-ground living biomass to assess relative maturity. MOG were displayed by major forest types (n = 22), landownerships (federal, state, private, and tribal), and Gap Analysis Project (GAP) management status overlaid on the NatureServe’s Red-listed Ecosystems and species, above-ground living biomass, and drinking water source areas. MOG total ∼67.2 M ha (35.9%) of all forest structural classes and were scattered across 8 regions with most in western regions. All federal lands combined represented the greatest (35%) concentrations of MOG, ∼92% of which is on national forest lands with ∼9% on Bureau of Land Management (BLM) and ∼3% on national park lands (totals do not sum to 100% due to minor mapping errors in the datasets). MOG on national forest lands supported the highest concentration of conservation values. However, national forests and BLM lands did not meet lower bound (30%) targets with only ∼24% of MOG in GAP1,2 (5.9 M ha) protection status. The vast majority (76%, 20.8 M ha) of MOG on federal lands that store 10.64 Gt CO2 (e) are vulnerable to logging (GAP3). If federal MOG are logged over a decade, and half their carbon stock emitted, there would be an estimated 0.5 ppm increase in atmospheric CO2 by 2030, which is equivalent to ∼9% of United States total annual emissions. We recommend upper bound (100%) protection of federal MOG, including elevating the conservation status of Inventoried Roadless Areas. This would avoid substantial CO2 emissions while allowing ongoing carbon sequestration to act as natural climate solutions to aid compliance with the Paris Climate Agreement and presidential executive orders on MOG and 30% of all lands and waters in protection by 2030. On non-federal lands, which have fewer MOG, regulatory improvements and conservation incentives are needed.

A tale of two selection biases: The independent effects of relative age and biological maturity on player selection in the Football Association of Ireland's national talent pathway

This study investigated the associations between biological maturation status (classified using the Khamis–Roche method for the percentage of predicted adult height at the time of observation) and relative age (expressed as a decimal value relative to the difference between birth date and competition cut-off date) and the extent to which their relative selection biases existed across competitive age groups in an analysis of players within the Football Association of Ireland's (FAI) national talent pathway. The players assessed were either from the U13 FAI National Academy ( n = 125), the Ireland U15 national team ( n = 18), or the Ireland U16 national team ( n = 16). A moderate to very large selection bias in favour of early maturing players was observed across all age groups, increasing in magnitude with successive age groups ( p &lt; 0.05). A total of 46–72% of players selected into the national talent pathway were early maturing; 0% of U15 and U16 players were late maturing. A relative age effect existed across all competitive cohorts ( p &lt; 0.05), although not increasing with chronological age and smaller in magnitude than maturation biases. A small positive correlation between relative age and absolute maturity status at U13 was observed, and an inverse correlation between relative age and relative maturity status at U15 ( p &lt; 0.01) was observed. There were no other significant correlations between relative or absolute maturity status and relative age. We encourage Football Associations to critically reflect upon their criteria for national talent squad selection; the current system diminishes the chances of selection for late maturing players.

Agritourism Farms: A Great Way to Promote Local Products

Online communication (Web 2.0) is an important tool that can assist consumers in choosing a service and/or buying a product and, if used effectively, can help businesses to improve organizational performance. This is a study of the websites of a sample of 4,080 Italian agritourism farms, which focuses on the construction, utility, and relative maturity of these businesses. The study entails an exploration of how and where the organization of websites is effective for the promotion of the features of agritourism farms and is therefore essential for providing recommendations for decisionmakers in the Italian agritourism sector. To test the study hypotheses, an extended model of internet commerce adoption (eMICA) is used, which is adapted to include the information reported on each agritourism farm website. Chi-square automatic interaction detection (CHAID) helps to analyze the differences in website design and vacation types on offer at the provincial level. The eMICA highlights the utility of using interactivity to measure the relative maturity of agritourism farm websites. In contrast, the CHAID decision tree shows how the diversification of vacation types is an important strategy for selling local agrifood products, especially to farm accommodation guests.

Career Maturity in Relation to Vocational Aspiration and Self-Concept among Senior Secondary School Adolescents

Students' careers are important in their lives because they will have to make decisions about their careers later in life. This study aims to examine the key predictors of Career Maturity between Vocational Aspiration and Self-Concept among the senior secondary school adolescents. Three measures are employed in the quantitative study design, including a self-concept questionnaire developed and normed by Saraswat (2011), the Occupational Aspiration Scale by J.S. Grewal (2011), and the Career Maturity Inventory by Nirmala Gupta (2013). These scales disseminated to students from the four senior secondary government and private schools of Kannauj district. Using the simple random sampling method, a total of 376 senior secondary school adolescents were involved in the study. The findings show that among senior secondary school students enrolled in both government and private institutions, vocational aspiration became a significant factor in predicting career maturity. Career Maturity was found to have significant correlation with Vocational Aspiration while no relationship was found with self-concept for total sample and sub samples. Female students were found to have better Career Maturity than males while opposite trend was seen for Vocational Aspiration. Although, the self-concept of males and females was observed to be similar. Moreover, Female students have better capability to make or choose proper vocational choices, including awareness required for choosing career according to their skills, interests, values and personality traits. However, male students were having more aspirations for the career or vocation.

Career Maturity in Relation to Vocational Aspiration and Self- Concept among Senior Secondary School Adolescents

Career Maturity in Relation to Vocational Aspiration and Self- Concept among Senior Secondary School Adolescents

Physicochemical characterization of cape gooseberry (Physalis peruviana L.) fruits ecotype Colombia during preharvest development and growth.

Cape gooseberry fruits are increasingly recognized due to their excellent organoleptic and functional characteristics as a food. As the cultivation of this fruit expands, it is necessary to determine the quality characteristics and evolution of the new growing zones. This study sought to characterize the growth and development of cape gooseberry fruits, Ecotype Colombia, in the Ventaquemada region (Department of Boyacá in Colombia). For the experiments, 50 plants were taken completely at random from which 20 flowers of the middle third were selected and marked considering that 50% of the flowers were open. The selected cape gooseberry plants were 9 months old from the establishment. Samples were carried out every 5-7 days to evaluate changes in different physiological and physicochemical properties of the fruits such as equatorial diameter, weight, dry matter, respiration intensity (RI), total soluble solids (SST), titratable acidity (TA), and maturity ratio (SST/TA). Logistic and modified enzyme kinetics models were fitted to represent the change in these characteristics as a function of growth time and to establish a suitable maturity index. A rapid increase in the growth and a substantive change in the properties of the fruits were observed between 36 and 45 days after anthesis (DAA) and stabilization between 60 and 65 DAA, which constitutes the stage of physiological maturity. At this stage, fruits with a polar/equatorial diameter of 2.2-2.5cm, 14.9% TSS, 2.2% TA, and 191.7 cm3 CO2 /g/d RI were obtained. Likewise, from the adjusted models, it was possible to identify these changes, especially for the relative growth rate (RGR), color index, and maturity ratio. PRACTICAL APPLICATION: In this work, we present the characterization of some physicochemical properties of cape gooseberry throughout its development and preharvest growth. This fruit is of wide interest due to its broad nutritional properties and is known as a "superfruit." The monitoring of the changes in the quality characteristics is important because it allows producers to define an optimum maturity stage for its commercialization. We also fit suitable regression models to relate the evolution in the product as a function of time and provide prediction tools to monitor fruit development. The above can help growers better schedule their production cycles.

Congenital Infections: Priorities and Possibilities for Resource-limited Settings.

Congenital Infections: Priorities and Possibilities for Resource-limited Settings.

Maturity-Associated Differences in Match Running Performance in Elite Male Youth Soccer Players.

To investigate the influence of maturation on match running performance in elite male youth soccer players. A total of 37 elite male youth soccer participants from an English professional soccer academy from the U14s, U15s, and U16s age groups were assessed over the course of 1 competitive playing season (2018-2019). Relative biological maturity was assessed using percentage of predicted adult height. A global positioning system device was used between 2 and 30 (mean = 8 [5]) times on each outfield player. The position of each player in each game was defined as defender, midfielder, or attacker and spine or lateral. A total of 5 match-running metrics were collected total distance covered, high-speed running distance, very high-speed running distance, maximum speed attained, and number of accelerations. Relative biological maturity was positively associated with all global positioning system running metrics for U14s. The U15/16s showed variation in the associations among the global positioning system running metrics against maturity status. A multilevel model which allowed slopes to vary was the best model for all parameters for both age groups. In the U14 age group, advanced maturation was associated with greater high-speed running distance. However, maturation did not contribute toward variance in any of the indices of running performance in the U15/16s. In the U15/16 age group, significance was observed in the spine/lateral playing positions when undertaking actions that required covering distance at high speeds. Maturation appeared to have an impact on match-running metrics within the U14s cohort. However, within the U15/16s, the influence of maturation on match-running metrics appeared to have less of an impact.

A Longitudinal Relationship between Self-Directed Learning Ability, Ego-Resilience and Career Maturity Using Autoregressive Cross-lagged Model

본 연구의 목적은 자기주도학습능력, 자아탄력성, 진로성숙도 간의 인과관계를 종단적으로 검증하고 시간의 변화에 따른 안정성과 상호예측력을 알아보는 데 있다. 이를 위하여 일반계 고등학교에 재학 중인 학생들을 대상으로 2016년부터 2018년까지 실시한 서울교육종단연구(SELS 2010) 7차(고1), 8차(고2) 및 9차(고3) 패널 데이터를 활용하여 자기회귀교차지연모형 검증을 실시하였다. 우선 연구모형을 검증하기 위한 가정인 동일성 제약들은 모두 충족되었다. 연구 결과, 첫째, 시간의 경과에 따라 자기주도학습능력, 자아탄력성, 진로성숙도는 다음 시점의 동일한 잠재변인들에 모두 통계적으로 유의한 정적 영향을 미치면서 안정적인 자기회귀효과를 유지하였다. 자기회귀계수의 상대적 크기는 자기주도학습능력이 가장 높았고, 다음으로 자아탄력성과 진로성숙도는 비슷하게 나타났다. 둘째, 시간의 흐름에 따라 자기주도학습과 진로성숙도의 관계에서 교차지연계수들은 모두 통계적으로 유의한 정적 관계를 보여주었고 인과적 상호예측력이 있음을 나타내고 있다. 또한, 자아탄력성과 진로성숙도의 관계에서도 교차지연효과가 유의한 정적 관계로 인과적 상호예측력을 보여주었다. 그러나 자기주도학습능력과 자아탄력성의 관계에서는, 이전 시점의 자기주도학습능력이 다음 시점의 자아탄력성에 영향을 미치는 교차지연효과는 정적으로 유의하였으나, 이전 시점의 자아탄력성이 다음 시점의 자기주도학습능력에 영향을 미치는 교차지연효과는 유의하게 예측되지 않았다. 이러한 연구 결과에 기초하여 논의하였고 시사점 및 후속연구에 관해 제언하였다.The primary goal of this study was to investigate the longitudinal stability and reciprocal relationship between self-directed learning ability, ego-resilience, and career maturity across time using the Seoul Education Longitudinal Study (SELS) panel data of Time 7 (first year of high school), Time 8 (second year), and Time 9 (third year). The autoregressive cross-lagged model (ARCLM) was employed to examine the autoregressive effects of within-subjects variables and cross-lagged effects of between-subjects variables. Results from the ARCLM revealed that previous self-directed learning ability, ego-resilience, and career maturity had significant effects on subsequent self-directed learning ability, ego-resilience, and career maturity, respectively, with stable autoregressive coefficients. In addition, self-directed learning ability of the first-year high school students predicted subsequent ego-resilience of the second-year students, and self-directed learning ability of the second-year students predicted subsequent ego-resilience of the third-year students, whereas ego-resilience did not significantly predict subsequent self-directed learning ability. Furthermore, the cross-lagged effects of self-directed learning ability in relation to career maturity and ego-resilience in relation to career maturity were statistically significant, indicating reciprocal relationships.

Helicoverpa zea (Lepidoptera: Noctuidae) Thresholds and Yield Compensation Between Soybeans with Determinate and Indeterminate Growth Habits

Soybean (Glycine max L.) is an important row crop in the United States and Helicoverpa zea (Boddie) is one of the most serious insect pests in this system. Economic thresholds for H. zea were developed from soybean varieties with determinate growth habits. However, southern USA farmers have recently planted more soybeans varieties with indeterminate growth habits. Trials were conducted with two determinate and two indeterminate varieties within the same relative maturity group. Levels were compared among groups with differing H. zea pressure (low, medium, high, naturally infested) and manipulated using insecticides. Our objectives were to evaluate yield compensation differences among determinate and indeterminate varieties at these different H. zea pressures and to see if the existing economic threshold should be adjusted between growth habits. Since H. zea larval populations varied across trials, we compared trials with low populations, high populations, and no population. Generally, larval counts did not differ among varieties. We found no yield differences among varieties or between growth habits, regardless of H. zea pressure. In the high population tests, yield was highest in the low population plots, but there was no compensation by the plant in yield components except in number of pods with one seed. In contrast, yield components varied widely across varieties, but these differences were independent of H. zea pressure. These results suggest the economic threshold can be used for determinate and indeterminate growth habits, but more research is needed to confirm this with a larger selection of varieties, planting dates, and maturity groups.

Artificial Neural Network for Discrimination and Classification of Tropical Soybean Genotypes of Different Relative Maturity Groups

Soybean has a recognized narrow genetic base that often makes it difficult to visualize available genetic and phenotypic variability and identify superior genotypes during the selection process. However, the phenotypic expression of soybean plants is highly affected by photoperiod and the cultivation of a given variety is performed in the latitude range that presents ideal conditions for its development based on its relative maturity group (RMG) for the optimization of the phenotypic expression of its genotype. Based on the above, this study aimed to evaluate the efficiency of artificial neural networks (ANNs) as a tool for the correct discrimination and classification of tropical soybean genotypes according to their relative maturity group during the population selection process with the aim of optimizing the phenotypic performance of these selected genotypes. For this purpose, three biparental populations were synthesized, one with a wide genetic variability for the RMG character obtained from the hybridization between genitors of maturity groups RMG 5 (Sub-tropical 23° LS) × RMG 9.4 (Tropical 0° LS) and two populations with a narrow variability obtained between genitors RMG 7.3 (Tropical 20° LS) × RMG 9.4 and RMG 5.3 × RMG 6.7, respectively. Criteria for comparing the developed ANN architecture with Fisher’s linear and Anderson’s quadratic parametric discriminant methodologies were applied to the data for the discrimination and classification of the genotypes. ANN showed an apparent error rate of less than 8.16% as well as a low influence of environmental factors, correctly classifying the genotypes in the populations even in cases of reduced genetic variability such as in the RMG 5 × RMG 6 population. In contrast, the discriminant functions were inefficient in correctly classifying the genotypes in the populations with genealogical similarity (RMG 5 × RMG 6) and wide genetic variability, with an error rate of more than 50%. Based on the results of this study, ANN can be used for the discrimination of genotypes in the initial generations of selection in breeding programs for the development of high performance cultivars for wide and reduced photoperiod amplitudes, even with fewer selection environments, more efficiently, and with fewer time and resources applied. As a result of similarity between the parents, ANN can correctly classify genotypes from populations with a narrow genetic base, in addition to pure lines and genotypes with a high degree of inbreeding.