Row Types Research Articles

Generic Programming with Extensible Data Types: Or, Making Ad Hoc Extensible Data Types Less Ad Hoc

We present a novel approach to generic programming over extensible data types. Row types capture the structure of records and variants, and can be used to express record and variant subtyping, record extension, and modular composition of case branches. We extend row typing to capture generic programming over rows themselves, capturing patterns including lifting operations to records and variations from their component types, and the duality between cases blocks over variants and records of labeled functions, without placing specific requirements on the fields or constructors present in the records and variants. We formalize our approach in System R𝜔, an extension of F𝜔 with row types, and give a denotational semantics for (stratified) R𝜔 in Agda.

Leaf thickness of barley: genetic dissection, candidate genes prediction and its relationship with yield-related traits.

In this first genetic study on assessing leaf thickness directly in cereals, major and environmentally stable QTL were detected in barley and candidate genes underlying a major locus were identified. Leaf thickness (LT) is an important characteristic affecting leaf functions which have been intensively studied. However, as LT has a small dimension in many plant species and technically difficult to measure, previous studies on this characteristic are often based on indirect estimations. In the first study of detecting QTL controlling LT by directly measuring the characteristic in barley, large and stable loci were detected from both field and glasshouse trials conducted in different cropping seasons by assessing a population of 201 recombinant inbred lines. Four loci (locating on chromosome arms 2H, 3H, 5H and 6H, respectively) were consistently detected for flag leaf thickness (FLT) in each of these trials. The one on 6H had the largest effect, with a maximum LOD 9.8 explaining up to 20.9% of phenotypic variance. FLT does not only show strong interactions with flag leaf width and flag leaf area but has also strong correlations with fertile tiller number, spike row types, kernel number per spike and heading date. Though with reduced efficiency, these loci were also detectable from assessing second last leaf of fully grown plants or even from assessing the third leaves of seedlings. Taking advantage of the high-quality genome assemblies for both parents of the mapping population used in this study, three candidate genes underlying the 6H QTL were predicted based on orthologous analysis. These results do not only broaden our understanding on genetic basis of LT and its relationship with other traits in cereal crops but also form the bases for cloning and functional analysis of genes regulating LT in barley.

Strategies of grain number determination differentiate barley row types.

Gaining knowledge on fundamental interactions of various yield components is crucial to improve yield potential in small grain cereals. It is well known in barley that increasing grain number greatly improves yield potential; however, the yield components determining grain number and their association in barley row types are less explored. In this study, we assessed different yield components such as potential spikelet number (PSN), spikelet survival (SSL), spikelet number (SN), grain set (GS), and grain survival (GSL), as well as their interactions with grain number by using a selected panel of two- and six-rowed barley types. Also, to analyze the stability of these interactions, we performed the study in the greenhouse and the field. From this study, we found that in two-rowed barley, grain number determination is strongly influenced by PSN rather than SSL and/or GS in both growth conditions. Conversely, in six-rowed barley, grain number is associated with SSL instead of PSN and/or GS. Thus, our study showed that increasing grain number might be possible by augmenting PSN in two-rowed genotypes, while for six-rowed genotypes SSL needs to be improved. We speculate that this disparity of grain number determination in barley row types might be due to the fertility of lateral spikelets. Collectively, this study revealed that grain number in two-rowed barley largely depends on the developmental trait, PSN, while in six-rowed barley, it mainly follows the ability for SSL.

Genetic Diversity and Population Structure of Serbian Barley (Hordeum vulgare L.) Collection during a 40-Year Long Breeding Period

Determination of genetic diversity and population structure of breeding material is an important prerequisite for discovering novel and valuable alleles aimed at crop improvement. This study’s main objective was to characterize genetic diversity and population structure of a collection representing a 40-year long historical period of barley (Hordeum vulgare L.) breeding, using microsatellites, pedigree, and phenotypic data. The set of 90 barley genotypes was phenotyped during three growing seasons and genotyped with 338 polymorphic alleles. The indicators of genetic diversity showed differentiation changes throughout the breeding periods. The population structure discriminated the breeding material into three distinctive groups. The principal coordinate analysis grouped the genotypes according to their growth habit and row type. An analysis of phenotypic variance (ANOVA) showed that almost all investigated traits varied significantly between row types, seasons, and breeding periods. A positive effect on yield progress during the 40-year long breeding period could be partly attributed to breeding for shorter plants, which reduced lodging and thus provided higher yield stability. The breeding material revealed a considerable diversity level based on microsatellite and phenotypic data without a tendency of genetic erosion throughout the breeding history and implied dynamic changes in genetic backgrounds, providing a great gene pool suitable for further barley improvement.

Genetic and Agro-morphological diversity in global barley (Hordeum vulgare L.) collection at ICARDA

Heat stress at later growth stage is one of the major limitations in achieving potential yield in barley. Incorporation of heat tolerance in the variety development process is an essential task that breeders would like to achieve by exploring new sources of genetic variability and their utilization. A better understanding of genetic variation in existing genotypes under heat stress is required to produce high yielding varieties with improved heat tolerance. An association mapping panel 2017 (AM2017), comprising of 316 genotypes, was evaluated under timely and late sown (heat stress) conditions for two consecutive crop seasons at Hisar in India during 2017–2019. Eight agro-morphological traits, mainly contributing to yield, were considered agro-morphological diversity study. Genetic diversity and population structure were explored by using the 50 K iSelect Illumina Barley SNP array. A set of 36,793 SNP markers, covering a genetic distance of 991.82 cM with an average marker density of 37.09 SNPs/cM, was obtained after quality filtration. The gene diversity (GD) and Polymorphic Information Content (PIC) at genome level was 0.362 and 0.289, respectively. In AM2017, two subpopulations were observed mainly due to the row types. Principal component analysis of agro-morphological traits revealed that days to heading and maturity along with spike length, spikelet number per spike and grain yield per plot were the most important traits in timely and late sown conditions. The information on agro-morphological genetic diversity under heat stress conditions will be useful in identifying heat tolerant genotypes for use in barley breeding programs.

Genetic analysis reveals four interacting loci underlying awn trait diversity in barley (Hordeum vulgare)

Barley (Hordeum vulgare) awns contribute to grain yield, but the genetic basis of awn development remains largely unclear. Five barley lines differing in awn traits and row types were used to create four F2 populations. Genetic analyses revealed that four pairs of genes were involved in awn development: A/a (awnless/awned), B/b (awnless/awned), H/h (hooded/straight), and L/l (long/short). Of these four loci, A, H and L functioned on both central rows (CR) and lateral rows (LR) of the barley spikes, while B exhibited effect only on LR. A and B had duplicate effects on LR, and both showed dominant epistasis to loci H and L, whereas H was epistatic to L. Meanwhile, A and B were found to be genetically linked, with a row-type locus V located between them. The genetic distances of A-V and B-V were estimated to be 9.6 and 7.7 cM, respectively. Literature search suggested that A, H and V may correspond to the reported Lks1, Kap1 and Vrs1, respectively, whereas B is a novel gene specifically controlling awn development on LR, designated as Lsa1 for lateral spikelet awnless 1. The only barley homolog of wheat awn inhibitor gene B1, HORVU2Hr1G077570, is a potential candidate of Lsa1.

Performance of Corn Cultivars in Different Row Spacing and Types of Fertilizations

Performance of Corn Cultivars in Different Row Spacing and Types of Fertilizations

Abstracting extensible data types: or, rows by any other name

We present a novel typed language for extensible data types, generalizing and abstracting existing systems of row types and row polymorphism. Extensible data types are a powerful addition to traditional functional programming languages, capturing ideas from OOP-like record extension and polymorphism to modular compositional interpreters. We introduce row theories, a monoidal generalization of row types, giving a general account of record concatenation and projection (dually, variant injection and branching). We realize them via qualified types, abstracting the interpretation of records and variants over different row theories. Our approach naturally types terms untypable in other systems of extensible data types, while maintaining strong metatheoretic properties, such as coherence and principal types. Evidence for type qualifiers has computational content, determining the implementation of record and variant operations; we demonstrate this in giving a modular translation from our calculus, instantiated with various row theories, to polymorphic λ-calculus.

Genome wide association studies (GWAS) of element contents in grain with a special focus on zinc and iron in a world collection of barley (Hordeum vulgare L.)

Genome wide association studies (GWAS) were carried out to map Quantitative Trait Loci (QTL) associated with element contents in the grain using 336 spring barley. Of the elements analyzed, Fe content ranged from 21.9 to 91.0 mg kg−1, Zn from 10.4 to 54.5 mg kg−1, Ba from 0.2 to 8.9, Ca from 186.4 to 977.5, Cu from 1.5 to 9.8, K from 353.2 to 7721.5, Mg from 1049.8 to 2024.2, Mn from 8.1 to 22.9, Na from 55.9 to 627.9, P from 2272.9 to 5428.8, S from 880.7 to 1898.0, Si from 19.1 to 663.2, and Sr from 0.35 to 2.62 mg kg−1. GWAS were carried out using 6519 SNP markers and multiple elements in MLM:PCA + K model in TASSEL software. Population analyses showed two sub-populations, primarily based on row types. GWAS for row types showed association with INTERMEDIUM-C, a modifier gene for lateral spikelet fertility in the 4H chromosome, validating current GWAS approach. GWAS also showed that 2 QTL for Ba, 2 for Ca, 4 for Cu, 11 for Fe, 2 for K, 3 for Mg, 6 for Mn, 4 for Na, 3 for S, 5 for Si, and 3 for Zn were mapped in barley chromosomes. The QTL identified in the current study are valuable for breeding nutrient dense barley cultivars in the future, especially Zn and Fe.

Hardware-Efficient Built-In Redundancy Analysis for Memory With Various Spares

Memory capacity continues to increase, and many semiconductor manufacturing companies are trying to stack memory dice for larger memory capacities. Therefore, built-in redundancy analysis (BIRA) is of utmost importance because the probability of fault occurrence increases with a larger memory capacity. A traditional spare structure that consists of simple rows and columns is somewhat inadequate for multiple memory blocks BIRA because the hardware overhead and spare allocation efficiency are degraded. The proposed BIRA uses various types of spares and can achieve a higher yield than a simple row and column spare structure. Herein, we propose a BIRA that can achieve an optimal repair rate using various spare types. The proposed analyzer can exhaustively search not only row and column spare types but also global and local spare types. In addition, this paper proposes a fault-storing content-addressable memory (CAM) structure. The proposed CAM is small and collects faults efficiently. The experimental results show a high repair rate with a small hardware overhead and a short analysis time.

Automatic detection of curved and straight crop rows from images in maize fields

A new method for detecting curved and straight crop rows in images captured in maize fields during the initial growth stages of crop and weed plants is proposed. The images were obtained under perspective projection with a camera installed on board and conveniently arranged at the front part of a tractor. The final goal is the identification of the crop rows with two purposes: a) precise autonomous guidance; b) site-specific treatments, including weed removal, where weeds are identified as plants outside the crop rows. Image quality is affected by uncontrolled lighting conditions in outdoor agricultural environments and gaps along the crop rows due to lack of germination or defects during planting. Also, different crop and weed plant heights and volumes appear at different growth stages affecting the crop row detection process. The proposed method was designed with the required robustness to cope with the above situations and consists of three linked phases: (i) image segmentation, (ii) identification of starting points for determining the beginning of the crop rows and (iii) crop rows detection. The main contribution of the method is the ability to detect curved and straight crop rows having regular or irregular inter-row spacing, even when both row types coexist in the same field and image. The performance of the proposed approach was quantitatively compared against six existing strategies, achieving accuracies between 86.3% and 92.8%, depending on whether crop rows were straight/curved with regular or irregular spacing, with processing times less than 0.64 s per image.

Discussion on the Effect of a Fluid Domain around Fins and Grid Discretization in Buoyancy-Driven Convection

ABSTRACTIn the numerical study of heat sinks, it is known that a sufficient amount of fluid domain should be added at each side of the heat sink. However, the question in this context is: what can be defined as sufficiently far away from the heat sink? Different authors use different sizes of the computational domain around the heat sink. In this work the impact of the size and location of the fluid domain on the calculated heat transfer coefficient is investigated. Three fin row types are studied: a rectangular, an interrupted rectangular, and an inverted triangular fin row. First, the influence of adding fluid domain to the sides of the heat sink is studied. A large decrease of the heat transfer coefficient on both sides and bottom is observed. Next, the influence of adding fluid domain on both the top and the sides is studied. For the rectangular fins, the impact on the lumped heat transfer coefficient is +12% compared to the case without any fluid domain added. For the inverted triangular fin shape, no net effect is observed on the lumped heat transfer coefficient. So the impact of adding fluid domain depends on fin shape that is investigated. For the sides only, a small amount of fluid needs to be added, while for the fluid domain on top of the heat sink, 130% of the equivalent fin height is found as a good option to simulate the fin in computational fluid dynamics.

Evaluation of Canadian barley breeding lines for Fusarium head blight resistance

He, X., Osman, M., Helm, J., Capettini, F. and Singh, P. K. 2015. Evaluation of Canadian barley breeding lines for Fusarium head blight resistance. Can. J. Plant Sci. 95: 923–929. Fusarium head blight (FHB) is a major challenge to the successful production of barley in Canada, as well as for end-users such as the malting and brewing industries. Due to the quantitative inheritance of FHB resistance, continuous effort is required to identify breeding lines with improved FHB resistance and incorporate them into crossing schemes to enhance FHB resistance. In the present study, 402 advanced breeding lines from Alberta, Canada, were evaluated in the FHB screening nursery at CIMMYT, Mexico. In 2011 and 2012, FHB incidence was measured on a scale of 1 to 4 to eliminate the most susceptible lines. In 2013 and 2014, 181 lines with the lowest disease scores in the previous 2 yr were tested in replicated experiments for field FHB index, Fusarium-damaged kernels, and deoxynivalenol content. Agronomic and morphological traits, specifically days to heading, plant height, and row and hull types were also evaluated in relations to FHB parameters. Correlation coefficients among the three FHB parameters in both 2013 and 2014 were all significant at P<0.0001, ranging from 0.36 to 0.63. Additional correlation analysis showed that late-maturing, tall, and two-row lines tended to have lower disease, whereas hull type did not show a significant correlation with FHB. Several lines with high and stable FHB resistance similar to that of the resistant checks were identified. These could be used in breeding programs as resistance sources or be registered as new cultivars if their overall attributes meet commercial standards.

Variations on variants

Extensible variants improve the modularity and expressiveness of programming languages: they allow program functionality to be decomposed into independent blocks, and allow seamless extension of existing code with both new cases of existing data types and new operations over those data types. This paper considers three approaches to providing extensible variants in Haskell. Row typing is a long understood mechanism for typing extensible records and variants, but its adoption would require extension of Haskell's core type system. Alternatively, we might hope to encode extensible variants in terms of existing mechanisms, such as type classes. We describe an encoding of extensible variants using instance chains, a proposed extension of the class system. Unlike many previous encodings of extensible variants, ours does not require the definition of a new type class for each function that consumes variants. Finally, we translate our encoding to use closed type families, an existing feature of GHC. Doing so demonstrates the interpretation of instances chains and functional dependencies in closed type families. One concern with encodings like ours is how completely they match the encoded system. We compare the expressiveness of our encodings with each other and with systems based on row types. We find that, while equivalent terms are typable in each system, both encodings require explicit type annotations to resolve ambiguities in typing not present in row type systems, and the type family implementation retains more constraints in principal types than does the instance chain implementation. We propose a general mechanism to guide the instantiation of ambiguous type variables, show that it eliminates the need for type annotations in our encodings, and discuss conditions under which it preserves coherence.

Agricultural practices altered soybean seed protein, oil, fatty acids, sugars, and minerals in the Midsouth USA.

Information on the effects of management practices on soybean seed composition is scarce. Therefore, the objective of this research was to investigate the effects of planting date (PD) and seeding rate (SR) on seed composition (protein, oil, fatty acids, and sugars) and seed minerals (B, P, and Fe) in soybean grown in two row-types (RTs) on the Mississippi Delta region of the Midsouth USA. Two field experiments were conducted in 2009 and 2010 on Sharkey clay and Beulah fine sandy loam soil at Stoneville, MS, USA, under irrigated conditions. Soybean were grown in 102 cm single-rows and 25 cm twin-rows in 102 cm centers at SRs of 20, 30, 40, and 50 seeds m-2. The results showed that in May and June planting, protein, glucose, P, and B concentrations increased with increased SR, but at the highest SRs (40 and 50 seeds m-2), the concentrations remained constant or declined. Palmitic, stearic, and linoleic acid concentrations were the least responsive to SR increases. Early planting resulted in higher oil, oleic acid, sucrose, B, and P on both single and twin-rows. Late planting resulted in higher protein and linolenic acid, but lower oleic acid and oil concentrations. The changes in seed constituents could be due to changes in environmental factors (drought and temperature), and nutrient accumulation in seeds and leaves. The increase of stachyose sugar in 2010 may be due to a drier year and high temperature in 2010 compared to 2009; suggesting the possible role of stachyose as an environmental stress compound. Our research demonstrated that PD, SR, and RT altered some seed constituents, but the level of alteration in each year dependent on environmental factors such as drought and temperature. This information benefits growers and breeders for considering agronomic practices to select for soybean seed nutritional qualities under drought and high heat conditions.

Pengujian Berbagai Tipe Tanam Jajar Legowo terhadap Hasil Padi Sawah

Planting wetland paddy by setting row space could be a method to increase rice production. Legowo system is row planting method where we are able to apply different row types on paddy field. The objective of this research was to identify the best row planting type of ‘Jajar Legowo’ on growth and yield of wetland paddy. Six row plantings, including 2:1 type (means 2 rows are splited by wide space/ legowo), 3:1 type, 4:1 type, 5:1 type, 6:1 type, and 7:1 typ, were tested in a Randomized Complete Block Design with 3 replications Results of the experiment revealed that the highest growth and yield as showed by total number of tillers (28), number of productive tillers (25), dry-mill rice (66.16 g per plant), and yield difference of dry-mill rice (50.43% per plot) was found at row planting type 2:1. Therefore, row planting type 2:1 can be selected as the best row.

Comparing Single-Row and Twin-Row Corn Production in the Mid South

Twin-row corn (Zea mays L.) has increased in the Mid South but with limited research. Comparisons of single- vs. twin-row irrigated corn stands of 25,700, 30,700, 35,000, and 39,200 plants/acre grown at N fertilizer rates of 180, 220, and 260 lbs N/acre were made at Stoneville, MS, in 2007 and 2008. Leaf area index (LAI) was greater (6.3) in twin rows than single rows (6.1) but was not affected by N fertilizer. LAI was greater in all stands in 2007 than 2008 due to more plants/acre and rainfall in July vs. drought in July 2008. Greater yields also occurred in 2007 than 2008. No yield differences occurred between row types except twin rows at 30,700 (238 bu/acre) and 35,000 (244 bu/acre) plants/acre in 2007 were greater than single rows (224 and 227 bu/acre, respectively). Row type nor N fertilizer affected 100-kernel weights, though they did decline in 2007 as stands increased from 25,700 (1.37 oz) to 30,700 (1.28 oz) plants/acre. In 2008, 100-kernel weights were less, with the two lower stands not differing (1.08 and 1.11 oz) and the two higher stands (1.05 oz) less than the 30,700 stand. Lodging occurred in 2007 and was greatest at 39,200 plants/acre. Aflatoxin and fumonisin were higher in 2008 (901.8 ppb and 8.6 ppm) than 2007 (0.4 ppb and 0.6 ppm) but unaffected by row type and N fertilizer. N fertilizer above 180 lbs/acre did not affect yield or other measured data.

Genetic diversity analysis of hulless barley from Shangri-la region revealed by SSR and AFLP markers

For adding the hulless barley resources of Shangri-la region to the global barley resource library, a basic work was done by us to assess their genetic diversity of this region. The genetic diversity of 60 hulless barley samples collected from three counties in Shangri-la region of Yunnan Province, were studied using SSR (simple sequence repeats) and AFLP (amplified fragment length polymorphism) markers. A total of 70 alleles were detected for 19 pairs of SSR primers, and 525 band containing 464 polymorphic bands were revealed for 5 pairs of AFLP primers. The value of polymorphism information content (PIC) ranged from 0.03 to 0.86 for SSR primers. The total numbers of alleles were 51, 55, 43 in three populations and the polymorphic bands were 188, 205 and 141. The genetic distances and genetic identity among the three populations showed their close relationship. The gene diversity among populations relative to the total population diversity (Gst) was 0.13 for SSR markers and 0.02 for AFLP markers and indicated that just 13 and 2% variations were among populations, respectively. The UPGMA cluster analysis revealed that all of the samples grouped randomly rather than clustered into distinct groups corresponding to their populations, row types and spring/fall types. We concluded that there was high genetic diversity in the population of Shangri-la region and the formation of diversity was related to complex environment and inhabitants' traditional practices.

Planting Date, Rate, and Twin‐Row vs. Single‐Row Soybean in the Mid‐South

Comparisons were made of single‐row vs. twin‐row soybean [Glycine max (L.) Merr.] production on a Beulah fine sandy loam (coarse‐loamy, mixed, active, thermic Typic Dystrudepts) (BFSL) and Sharkey clay (very‐fine, smectitic, thermic Chromic Epiaquerts) (SC) in 2009 and 2010 at Stoneville, MS. Seeding rates of 20, 30, 40, and 50 seed m−2 were planted on beds in 102 cm single rows or 25 cm twin rows with 102 cm centers. Three planting dates, mid‐April and mid‐May representing the Early Soybean Production System (ESPS) and mid‐June common to double‐crop soybean were made. Data included plants at growth stage R4 (full pod), nodes and pods plant−1, yield, seed weight, and seeds m−2. Twin rows yielded more than single rows on both soils (3.8 Mg ha−1 vs. 3.6 Mg ha−1 on BFSL; 4.2 Mg ha−1 vs. 4.0 Mg ha−1 on SC). Yields in 2010 were less than 2009 due to drought and heat stress. Delayed planting across row types decreased yields as much as 40% while increasing seeding rates had no effect. Twin rows produced more plants m−2 than single rows. Differences in nodes plant−1 were noted but did not affect yield. Pods per plant did not differ between row configurations on either soil. Seeding rates above 30 seeds m−2 did not produce greater yields and above 50 seeds m−2 on the BFSL produced seed with less weight. Twin–rows generally produced more seeds per m2 than single rows. Small yield increases and high equipment costs make considering a twin‐row planter's usefulness with other crops important before purchasing it for soybean production.

Contact, closure, topology, and the linking of row and column types of relations

Forming closures of subsets of a set X is a technique that plays an important role in many scientific disciplines and there are many cryptomorphic mathematical structures that describe closures and their construction. One of them was introduced by Aumann in the year 1970 under the name contact relation. Using relation algebra, we generalize Aumann’s notion of a contact relation between X and its powerset 2 X and that of a closure operation on 2 X from powersets to general membership relations and their induced partial orders. We also investigate the relationship between contacts and closures in this general setting and present some applications. In particular, we investigate the connections between contacts, closures and topologies and use contacts to establish a one-to-one correspondence between the column intersections space and the row intersections space of arbitrary relations.