Kernel Hardness Research Articles

Virulence Dynamics and Breeding for Resistance to Stripe, Stem, and Leaf Rust in Canada Since 2000.

Wheat (Triticum spp.) is a major field crop in Canada in terms of acreage, annual production, and export market value. There are nine classes of Canadian wheat based on growth habit (winter or spring), kernel hardness (hard or soft), seed coat color (red or white), and quality factors (grain protein content and gluten strength). Wheat was described by Newman in 1928 as "the economic fairy to the industrial and commercial life of Canada, having built practically the whole economic structure of the Prairie Provinces." Wheat production in Canada is affected by several biotic and abiotic stresses. The major abiotic stresses are frost damage, drought, and heat stress. Among biotic stresses, diseases caused by fungal pathogens are the most important although wheat streak mosaic virus (WSMV) has caused some localized outbreaks in some years. In context of cultivar registration in Canada, there are certain diseases that breeders have to take into account while developing resistant cultivars. The Prairie Recommending Committee for Wheat, Rye, and Triticale (PRCWRT) classify wheat diseases into priority one, priority two, and priority three depending on prevalence and potential damage they can cause. However, priority one diseases are more of a concern and a minimum level of resistance in commercial cultivars is recommended for those.

Suitability of foliar N applied to rainfed maize in permanent beds after 12 crop seasons of granular N application

Yield and kernel quality of rainfed maize as affected by N fertilizer has been generally evaluated through the application of granular N sources at high rates. The purpose of this work was to estimate the response of maize yield and quality (kernel hardness—floating index, weight and test weight -, P uptake and protein) to foliar N application and preceding granular N. Data for this report were collected in 2014 and 2015 in a long-term experiment established in 2002 under permanent beds in a split plot arrangement. Main plot treatments were three foliar N rates (0, 4.5 and 9 kg ha−1) laid out on the top of four preceding granular N rates (0, 20, 40 and 60 kg ha−1) applied from 2002 to 2013 as subplots. Weather conditions were relatively wetter in 2014 than 2015. In 2014, test weight and floating index improved over that in 2015. Foliar application of 9 kg N ha−1 enhanced yield and protein. In 2014, yield response to preceding N rates showed an increasing trend whereas in 2015 response was null. Kernel P uptake response to preceding N rates showed a differential reaction among foliar N rates; 9 kg ha−1 showed the greatest uptake. Kernel floating index was associated to kernel P uptake. Apparently, this relationship has not been previously reported. Results suggests that the application of 9 kg N ha−1 to foliage of rainfed maize grown in permanent beds has the potential to substitute the traditional fertilization practice of granular N sources.

Effects of wheat kernel size on hardness and various quality characteristics

Kernel size and hardness are important for millers and they should be controlled prior to milling. The kernel hardness also determines end-use quality of wheat. The objective of this study was to determine the effect of kernel size on wheat kernel characteristics, especially kernel hardness, milling yield and various flour quality properties. Three bread wheat varieties (Bayraktar 2000, Demir 2000 and Ikizce 96) were used after separating them into three kernel size groups. As expected, 1000 kernel weight significantly (P<0.05) decreased with decreasing kernel size. Results of three hardness tests (single kernel characterisation system, pearling index and particle size index) were parallel and hardness of the samples significantly increased (P<0.05) as the kernel size decreased. Flour yields were generally lower in the smaller kernels. However, the decrease in flour yield was not significant for cv Bayraktar 2000. In two cultivars protein content and wet gluten had a significant (P<0.05) decreasing tendency with decreasing kernel size while those of the third cultivar were not affected by kernel size. Sedimentation values of the samples were not affected by kernel size. Overall, small kernels did not seem to influence flour quality while they generally had a detrimental effect on milling yield.

ESTIMATION OF THE VARIETIES WITH DIFFERENT ECOLOGICAL ORIGIN ACCORDING TO THEIR MAIN TRAITS AND PROPERTIES

The article presents the results of productivity and grain quality of 47 winter durum wheat varieties of various ecological origin studied in 2016–2018. All studied samples belong to semi-dwarf and dwarf forms (height of 61–105 cm). Semi-dwarf forms possessed high lodging resistance (3.9 points). The grain harvest of the main part (89.3%) of the samples ranged from 8.41 to 9.65 t/ha in the environmental test. Only three varieties (“Lazurit”, “Agat Donskoy”, “Andromeda”) in the winter durum wheat trial are characterized with high yields ranging from 9.65–10.0 t/ha. The yield of the standard variety of “Khristella” was 9.03 t / ha on average in 2016- 2018. The varieties “Kondor” (116.8%), “Zolotko” (123.0%), “Afina” (126.9%) showed high frost tolerance of the plants through the years of research, in comparison with the standard variety “Donchanka” (100%). In the ecological test the main part (68%) of winter durum wheat varieties possessed large grain. “1000-grain weight” was more than 40 g: “Amazon” (42.9 g), “Lazurit” (47.7 g), “Diona” (42.1 g), “Alyi Parus” (43.7 g), “Dnepryana” (45.4 g), “Krupinka” (46.9 g), etc. The studied samples had high percentage of protein (13.6–15.1%), gluten (22.8–27.0%), SDS-sedimentation (30–45 ml), carotenoids (468–779 μg/%), nature weight (777.0–819.0 g/l), kernel hardness (85–98%). The technical and culinary qualities of the pasta made from the main part of the samples were evaluated as excellent (the varieties “Donchanka”, “Oniks”, “Kiprida”, “Atoll”, “Kermen”, “Winter Gold”, etc.) and as good (the varieties “Teya”, “Eirena”, “Lazurit”, “Diona”, “Alyi Parus”, “Krupinka”, “Afina”, etc.).

Multi-environment analysis of grain quality traits in recombinant inbred lines of a biparental cross in bread wheat (Triticum aestivum L.)

A set of 286 recombinant inbred lines (RILs) along with the parents and a popular wheat variety in India were grown for two consecutive years at three locations belonging to the two major wheat growing zones of India and evaluated for four grain quality traits. Rare recombinants with high trait value appeared for protein content (PC), thousand-kernel weight (TKW), sedimentation value (SV), and kernel hardness (KH). The magnitude of environmental effects was more pronounced than genotypic effects and genotype-environment interaction (GEI). The cumulative contribution of environment and GEI components to the total variance was highest in the expression of PC followed by TKW, SV, and KH. The top five percent (14 RILs) of genotypes with high trait value were subjected to Eberhart and Russell (1966) (ER), genotype and genotype-environment (GGE) and additive main effects and multiplicative interaction (AMMI) stability models. Five RILs were identified as stable in all the three stability models. RIL61 with 38.8%, RIL101 with 8.9%, RIL226 with 26.1% superiority over check variety were the most stable genotypes in all the three stability models for PC, TKW and KH, respectively. RIL113 was found to be stable genotype in ER and GGE models, whereas, RIL231 was the most stable genotype in AMMI and GGE models in the expression of SV. These common stable genotypes with high trait value identified through ER, AMMI and GGE models could be potential donors in active breeding programs to develop high yielding wheat varieties with improved PC, TKW, SV and KH.

Role of yield genetic progress on the biochemical determinants of maize kernel hardness

Maize kernel hardness is a key attribute for the global maize processing industry. Breeding for on-farm yield has decreased kernel hardness. However, the underlying changes in zeins and starch composition, mechanistically related to kernel hardness, are unknown. We evaluated changes in zein and starch composition of 32 commercial hybrids released from 1965 to 2016 in Argentina. Kernel protein concentration decreased (∼25%), but zein concentration decreased at higher rates (45%). Zein fractions, Z1 and Z2, decreased throughout the study period. However, the concentration of specific Z2 components decreased (C1 and E zein), while others increased (C2) with hybrid release year. Hardness descriptors all were positively correlated with C1 and E zein concentration and negatively with C2 concentration. Kernel starch and amylose concentrations increased with hybrid release year. No clear changes in amylose to starch ratio were apparent over time. Significant genotype differences in amylose to starch ratio were evident (p < 0.001), but these differences were not correlated to hardness changes. Yield improvement has indirectly changed kernel composition, affecting hardness. Our results limit the relevance of starch components to hardness changes, reinforcing the role of specific zein fractions as observed throughout 50 years of breeding.

The assessment of grain quality indicators in spring barley cultivars and lines

The requirements for assessment of new barley cultivars quality, imposed on plant breeding research, can be very different, even contradictory, depending on the intended use. The study of 13 competitive variety test numbers carried out in Moscow region in 2013-2018 helped to reveal the most promising ones, capable of producing grain with high biochemical and technological quality indicators. The great value for forage use was demonstrated by the samples with a high protein and essential amino acid lysine content as well as a high level of exchange energy in the grain. It has been established that a new forage variety Zlatoyar accumulated the maximum protein content (13.9%) and essential amino acid lysine content (0.52%) with productivity of 7.55 t/ha in different by humidity years. The grain of naked barley dyhaploid form 9h1137 had the optimal nutritious content: 151 g of crude protein, 31 g of crude fat, 667 g of nitrogen-free extractives, and 18 g of cellulose per 1kg of dry mass. It was noted, that those cultivars were characterized by the exchange energy of 11.39-11.82 Mj per 1 kg of cattle forage, and 13.22-14.33 Mj per 1 kg of pig forage. The valuable material for brewery purposes corresponding with the international quality standards has been developed. The Nadezhny variety was selected as well as promising lines 141/1-09 h 746; 85/1-13 h 1067, 181/3-12 h 897, which had a higher content of extractives in the grain (79.9-82.5%). In favorable vegetation conditions, they had grain protein content of 10.6-11.2%, which corresponded with the highest grade of the international standards for malting qualities of grain. In dry vegetation conditions, the protein content did not exceed 12.4%. The edibility characteristics of barley cultivars were evaluated by technological parameters of grain and porridge as a finished product. The laboratory test for the barley groat qualities gave the following results: the grain unit (709-711 gram per liter), 1000 grain mass (50.551.8 g), kernel hardness (42.8-46.2%), groat grain output per 4 minutes (56.5-57.7%), the color of finished porridge (4.8-5.0 grades). It helped to identify the Nur and the Zlatoyar varieties as especially valuable for peeled-barley and pearl barley groats.

Genome-wide association study of six quality traits reveals the association of the TaRPP13L1 gene with flour colour in Chinese bread wheat.

SummaryFlour colour, kernel hardness, grain protein content and wet gluten content are important quality properties that determine end use in bread wheat. Here, a wheat 90K genotyping assay was used for a genome‐wide association study (GWAS) of the six quality‐related traits in Chinese wheat cultivars in eight environments over four years. A total of 846 significant single nucleotide polymorphisms (SNPs) were identified, explaining approximately 30% of the phenotypic variation on average, and 103 multienvironment‐significant SNPs were detected in more than four environments. Quantitative trait loci (QTL) mapping in the biparent population confirmed some important SNP loci. Moreover, it was determined that some important genes were associated with the six quality traits, including some known functional genes and annotated unknown functional genes. Of the annotated unknown functional genes, it was verified that TaRPP13L1 was associated with flour colour. Wheat cultivars or lines with TaRPP13L1‐B1a showed extremely significantly higher flour redness and lower yellowness than those with TaRPP13L1‐B1b in the Chinese wheat natural population and the doubled haploid (DH) population. Two tetraploid wheat lines with premature stop codons of the TaRPP13L1 gene mutagenized by ethyl methanesulfonate (EMS) showed extremely significantly higher flour redness and lower yellowness than wild type. Our data suggest that the TaRPP13L1 gene plays an important role in modulating wheat flour colour. This study provides useful information for further dissection of the genetic basis of flour colour and also provides valuable genes or genetic loci for marker‐assisted selection to improve the process of breeding quality wheat in China.

Expression of Puroindoline a in Durum Wheat Affects Milling and Pasting Properties.

Durum wheat has limited culinary utilizations partly due to its extremely hard kernel texture. Previously, we developed transgenic durum wheat lines with expression of the wildtype Puroindoline a (Pina) and characterized PINA’s effects on kernel hardness, total flour yield and dough mixing properties in durum wheat. The medium-hard kernel texture is potentially useful for exploring culinary applications of durum wheat. In the present study, we examined the milling parameters and flour attributes of the transgenic lines, including particle size distribution, damaged starch and water binding capacity. PINA expression results in increased break and reduction flour yield but decreased shorts. PINA expression also leads to finer flour particles and decreased starch damage. Interestingly, PINA transgenic lines showed increased peak viscosity and breakdown viscosity but leave other flour pasting parameters generally unaltered. PINA transgenic lines were associated with increased small monomeric proteins, appearing to affect gluten aggregation. Our data together with several previous results highlight distinct effects of PINs on pasting properties depending on species and variety. The medium-hard kernel texture together with improved pasting parameters may be valuable for producing a broader range of end-products from durum wheat.

Tamales texture properties as a function of corn endosperm type

Tamales are a kind of steam cooked small cakes usually made with nixtamalized cornmeal, pork lard, salt and wrapped in corn cob bracts. Nowadays, tamales could be considered as an essential dish for cuisines of almost all Latin America and even the Southern United States. Tamales' flavour is simple and quite neutral as they can be filled with different sauces and fillings give them their typical organoleptic richness. Additionally, the firm, spongy, slightly resilient texture is typical and distinctive of this food. Moreover, texture is important because it is a quality which allows the dough to adequately hold the fillings. In this study, changes in the texture properties of tamales as a function of corn endosperm (hard, intermediate and soft endosperm) were evaluated. Tamales with the highest content of Flint (hard) cornmeal had the highest adhesiveness and the lowest gumminess. Conversely, tamales richer in Floury (soft) cornmeal had the highest gumminess and the lowest adhesiveness. Binary blends produce values close to the average, just as the Dent (intermediate) cornmeal yields intermediate effects. There was no synergistic or antagonistic effect caused by the mixture of the races cornmeal. Variations in the tamales texture properties are influenced by the kernel hardness, the cornmeal particle size dispersion and its amylose content.

Diversity of Puroindoline genes and their association with kernel hardness in Chinese wheat cultivars and landraces

Kernel hardness is a key trait that greatly affects the milling and baking qualities of common wheat. Kernel hardness is largely controlled by Pina and Pinb genes. Here, we investigate the allelic diversity of Pina and Pinb genes in a collection of 107 Chinese wheat cultivars and landraces. The kernel hardness values of these accessions were determined in two field seasons (2016/2017 and 2017/2018 seasons), and they were strongly correlated between the 2 years, with hardness indexes ranging from 5.4 to 91.8. Five known Pina-D1 alleles and four known Pinb-D1 alleles were detected. In particular, we identified a novel Pina-null allele (designated Pina-D1z) with a 3382-bp deletion that can be detected by the new molecular marker Pina-N5. We also identified a Pina/Pinb double null allele containing a ~ 29-kb deletion. They are useful genotypes for kernel texture improvement. The most frequent genotypes in these accessions were Pina-D1a/Pinb-D1a and Pina-D1a/Pinb-D1b (39.3% and 34.6%, respectively), followed by Pina-D1a/Pinb-D1p (13.2%). A comparison of genotypes between the present study and previous studies suggests that Chinese wheat landraces have more allelic variations in the Pina gene than do cultivars. An association analysis of Puroindolines with kernel hardness shows that 15 Pina-D1 alleles and 6 Pinb-D1 alleles could be associated with hard-kernel phenotypes in common wheat. Notably, this study suggests that Chinese landraces are a valuable resource of genetic variability in Puroindoline genes and provides a deeper understanding of the genotype-to-phenotype association of Puroindoline genes.

Single kernel wheat hardness estimation using near infrared hyperspectral imaging

Wheat is a major component of human diets across the world; hence, it is important to produce superior quality wheat for consumption. Hardness of wheat is one of its major quality and end-use determinants and it is desirable that this parameter could be rapidly and non-destructively measured along with its other functional attributes. Recent research has established that a number of quality parameters could be accurately measured using near infrared (NIR) hyperspectral imaging. In order to fully characterize wheat kernels using NIR hyperspectral imaging, this study aims to provide an optimal methodology to predict hardness of individual kernels. The predicted hardness of wheat kernels using this non-destructive imaging technique was referenced against the industry adopted hardness index (HI). Principal component analysis (PCA) was used as an exploratory method for classification of wheat kernels based on their hardness index into three categories of soft, medium, and hard.Various spectral pre-processing techniques were used and the best combination (Savitzky–Golay 1st derivative with 11 smoothing points followed by orthogonal signal correction and mean centering) was selected for partial least squares (PLS) regression and artificial neural network (ANN) models. The PLS model yielded moderate prediction of wheat hardness for calibration (R2 = 0.81 and RMSECV = 10.85) and prediction (R2 = 0.80 and RMSEP = 12.90). The ANN superseded the PLS model for calibration (R2 = 0.94 and RMSECV = 5.38) and prediction (R2 = 0.90 and RMSEP = 6.59). Although, these preliminary results have clearly established the potential of hyperspectral imaging for non-destructive and on-line pre-screening of individual wheat kernels for hardness determination, further studies on larger datasets are needed to scale-up the technique to commercial throughput levels.

Exploratory studies on components of variability for seed longevity and quality traits in bread (Triticum aestivum) and durum (Triticum durum) wheat

A set of 53 wheat genotypes were evaluated for different quality and longevity related traits at NBPGR, New Delhi, India. The selected genotypes included both durum and bread wheat varieties released in India between 1970 and 2014, and bread wheat germplasm lines for comparison. Bread wheat varieties were good repositories for sedimentation value (SV), whereas, durum varieties for kernel hardness (KH) and germplasm lines for grain iron (Fe), zinc (Zn), and thousand kernel weight (TKW). Both vigor index-1 and 2 after controlled deterioration (VIACD-1 and VIACD-2) was highest for durum varieties followed by bread wheat germplasm lines and varieties. Therefore, seed longevity of durum varieties, bread wheat germplasm lines, and bread wheat varieties, respectively, was good, intermediate and poor. Broad-sense heritability was high for all the studied traits except germination percentage before controlled deterioration (GPBCD). Genetic advance as per cent mean (GAM) was high for all the studied traits, with the exception of moisture content (MC) and GPBCD. Six genotypes (IC 542394, IC 542391, IC 542416, IC 542431, IC 542426, and IC 542387) were good storers and also contained high Fe and Zn, which can be used in breeding programs to improve seed storability, and Fe and Zn content. Both intra species and inter species variability were observed for all the studied traits. The close association observed between Fe and Zn may help in improving both the traits simultaneously. Electrical conductivity (EC) of the seed leachates can be used as a surrogate trait for indirect selection for seed longevity of genotypes due to its significant negative association.

Water deficit and heat stress induced alterations in grain physico-chemical characteristics and micronutrient composition in field grown grain sorghum

The surge in sorghum-based foods as a gluten-free alternative for cereals like wheat, has directed sorghum research towards understanding and improving grain quality parameters. Since sorghum is usually grown in arid and semi-arid environments, is often prone to terminal water deficit and heat stress, inducing significant yield and quality losses. In environment 1, 24 genotypes assembled from diverse geographic locations, representing major sorghum growing regions of the world were grown in irrigated and dryland conditions. In environment 2, heat stress was imposed on the same 24 genotypes by placing custom-built field-based heat tents on already established plants, starting from booting until maturity. Water-deficit stress increased kernel hardness and total protein in grain, decreased protein digestibility, and micronutrient composition. Heat stress recorded lower total protein, protein digestibility, micronutrient composition and higher kernel hardness than control. Irrespective of the stress, larger kernels recorded higher total protein, protein digestibility and micronutrient composition, but lower total starch and kernel hardness. Almost all the measured grain micronutrients (Zn, Fe, Mn and Cu) were reduced under both stresses compared to control. Genotypes such as SC372 and RTx7000 which maintained desired grain quality parameters under stress conditions can help in incorporating quality traits into sorghum improvement programs.

Influence of corn hybrid, kernel traits, location, and dry rolling or steam flaking on ruminal digestibility in beef cattle

Three trials were conducted to evaluate the effect of corn hybrid, kernel traits, growing location, and dry rolling or steam flaking on DM or starch digestibility or both. Trial 1 used 72 commercially available corn hybrids to evaluate the influence of hybrid on kernel characteristics and their effect on digestibility. Kernel characteristics evaluated were test weight, 1,000-kernel weight, and kernel hardness using the Stenvert hardness test. All analyses were conducted on dry, whole corn samples, and DM digestibility was determined for dry-rolled corn samples. Trial 2 used 12 hybrids to evaluate steam flaking or dry rolling on DM and starch digestibility. Flaking and flaking characterization were conducted at the Department of Grain Science and Industry at Kansas State University. Trial 3 used 132 commercially available corn hybrids grown in 3 separate locations to evaluate the effect of growing location, hybrid, and kernel characteristics on DM digestibility. Hybrids evaluated represented a wide range in relative maturity and, therefore, were separated into similar maturity groups for analysis. Results from trial 1 suggest that softer kernels are more digestible than harder kernels. A 27% difference in DM digestibility was found across hybrids when processed as dry-rolled corn. Results from trial 2 show that steam flaking improved DM digestibility (P < 0.01) from 5 to 29% and starch digestibility (P < 0.01) from 8 to 36% compared with dry rolling. Results from trial 3 suggest that DM digestibility is affected by corn hybrid (P < 0.05) but did not show consistent relationships with kernel characteristics. Our results also suggest that hybrid and growing location may interact, resulting in difficulty separating hybrid differences across locations. Overall, the results of these trials suggest that a softer kernel and a lighter-density flake improve digestibility and that hybrids vary in digestibility.

Fizičke karakteristike i nutritivni kvalitet odabranih genotipova kukuruza iz srbije različitih u tvrdoći i boji zrna

Physical quality traits (1000-kernel weight, density, milling response and soft endosperm portion), basic chemical (starch, protein, oil, cellulose and ash) and amino acids composition of ten ZP maize genotypes differing in kernel hardness and colour were studied. The objectives of this study were to characterize differences in ZP maize genotypes regarding to various physical traits and nutritional quality parameters such as basic chemical and amino acid composition and the data was correlated to find the interrelationship between these parameters. Kernel physical traits and chemical composition significantly varied among tested genotypes. A significant negative correlation was found between protein content and portion of soft endosperm as well as a significant positive correlation between protein content and two physical traits, milling response and density. Protein content showed a non-significant negative correlation with starch content. The results showed that the protein content exhibited negative correlation with lysine as well as positive correlation with methionine. It has not been observed a significant improvement in the amino acid composition regarding the specialty genotypes such as the selected white and red kernels and popping maize genotypes. The information presented in this study could be useful for the utilization improvement of maize kernel and the development of maize-based ingredients to prepare nutritious feed and food products.

Quantitative analysis of the grain amyloplast proteome reveals differences in metabolism between two wheat cultivars at two stages of grain development

BackgroundWheat (Triticum aestivum L.) is one of the world’s most important grain crops. The amyloplast, a specialized organelle, is the major site for starch synthesis and storage in wheat grain. Understanding the metabolism in amyloplast during grain development in wheat cultivars with different quality traits will provide useful information for potential yield and quality improvement.ResultsTwo wheat cultivars, ZM366 and YM49–198 that differ in kernel hardness and starch characteristics, were used to examine the metabolic changes in amyloplasts at 10 and 15 days after anthesis (DAA) using label-free-based proteome analysis. We identified 523 differentially expressed proteins (DEPs) between 10 DAA and 15 DAA, and 229 DEPs between ZM366 and YM49–198. These DEPs mainly participate in eight biochemical processes: carbohydrate metabolism, nitrogen metabolism, stress/defense, transport, energetics-related, signal transduction, protein synthesis/assembly/degradation, and nucleic acid-related processes. Among these proteins, the DEPs showing higher expression levels at 10 DAA are mainly involved in carbohydrate metabolism, stress/defense, and nucleic acid related processes, whereas DEPs with higher expression levels at 15 DAA are mainly carbohydrate metabolism, energetics-related, and transport-related proteins. Among the DEPs between the two cultivars, ZM366 had more up-regulated proteins than YM49–198, and these are mainly involved in carbohydrate metabolism, nucleic acid-related processes, and transport.ConclusionsThe results of our study indicate that wheat grain amyloplast has the broad metabolic capability. The DEPs involved in carbohydrate metabolism, nucleic acids, stress/defense, and transport processes, with grain development and cultivar differences, are possibly responsible for different grain characteristics, especially with respect to yield and quality-related traits.

Mapping kernel texture in a soft durum (Triticum turgidum subsp. durum) wheat population

Kernel texture (”hardness”) is one of the major determinants of wheat quality and is primarily controlled by the Puroindoline (Pin) genes, located at the Hardness (Ha) locus. The absence of the Ha locus is responsible for the extremely hard kernels of durum wheat (T. turgidum subsp. durum). Recently, the Pin genes from a soft common wheat variety were introgressed into durum wheat through homoeologous recombination. The objective of this study was to map kernel hardness in a soft durum wheat population derived from the cross between the varieties “Creso” and “Langdon 1–678“. In all, 428 F6 lines were evaluated for kernel hardness through the Single Kernel Characterization System; Hardness Index (HI) values ranged from −2 to 44. The same lines were genotyped using genotyping-by-sequencing, targeted amplicon sequencing, and sequence-tagged-site markers. A total of 8537 markers were used to conduct single marker-trait association analysis and two major significant regions were identified on chromosomes 3AL and 6AS each responsible for an additive effect of ∼6 HI units. Kompetitive allele specific markers targeting these regions were selected and tested in the whole population. To date, this is the first study to investigate the genetic factors behind hardness variation in durum wheat.

Zea mays L. hybrids kernels evaluated by image analysis tools

Received: 2018-06-07 | Accepted: 2018-06-19 | Available online: 2018-06-30 https://doi.org/10.15414/afz.2018.21.02.77-83 The aim of this study was to distinguishing between kernels of maize hybrids by the use of image analysis tools. We analyzed 10 registered Zea mays L. hybrids (5 – dent, 2 – semi-flint to flint, and 3 – semi-flint to dent type). Different parameters on ventral, dorsal, corolla side, and lateral side cross section of kernel were measured. Sample per each hybrid comprised 50 maize kernels. Acquired bio-images were processed by software Zeiss AxioVision Rel. 4.8. We analyzed the segmented regions of interest on the kernels. The data for area (mm 2 ), height and width (mm) were gathered from these regions. The hybrid ZE EDOX significantly differed (p < 0.05) from all other hybrids almost in all traits. It is the hybrid with the smallest area of the whole kernel, floury endosperm proportion, and depressed part on corolla. The new trait the area of the depressed part on the kernel corolla was measured. The hybrids with smaller proportion of floury endosperm had smaller area of depressed part, and vice versa. The image analysis methods can usefully contribute to selection of proper hybrids for different types of use. Keywords: maize, Zea mays L., kernel, image analysis References BLASCHKE, T. et al. (2014) Geographic Object-Based Image Analysis – Towards a new paradigm. In ISPRS Journal of Photogrammetry and Remote Sensing, vol. 87, pp. 180–191. https://doi.org/10.1016/j.isprsjprs.2013.09.014 DE CARVALHO, M. L. M., VAN AELST, A. C., VAN ECK, J. W., HOEKSTRA, F. A. (1999) Pre-harvest stress cracks in maize (Zea mays L.) kernels as characterized by visual, X-ray and low temperature scanning electron microscopical analysis: effect on kernel quality. In Seed Science Research, vol. 9, pp. 227–236. DELL´AQUILA, A. (2006) Computerised seed imaging: a new tool to evaluate germination quality. In Communications in Biometry and Crop Science, vol. 1, no. 1, pp. 20–31. ERASMUS, C. (2003) Maize kernel translucency measurement by Image Analysis and its relationship to vitreousness and dry milling performance. PhD thesis. Pretoria: University of Pretoria. FOX, G. and MANLEY, M. (2009) Hardness methods for testing maize kernels. In Journal of Agricultural and Food Chemistry, vol. 57, no. 13, pp. 5647–5657. doi: https://doi.org/10.1021/jf900623w GLASBEY, C. A. and HORGAN, G. W. (2001) Image analysis in agriculture research. In Quantitative Approaches in System Analysis, special issue, vol. 23, pp. 43–54. GUELPA, A., DU PLESIS, A., KIDD, M., MANLEY, M. (2015) Nondestructive estimation of maize (Zea mays L.) kernel hardness by means of an X-ray micro-computed tomography (μCT) density calibration. In Food and Bioprocess Technology, vol. 8, no. 6, pp. 1419–1429. JANDA, J. and MICHALEC, V. (1982) Mayze. Bratislava: Priroda. 408 p. MUTTERER, J. and ZINCK, E. (2013) Quick‐and‐clean article figures with FigureJ. In Journal of Microscopy, vol. 252, pp. 89– 91. doi: https://doi.org/10.1111/jmi.12069 ROBUTTI, J. L., HOSENEY, R. C. and WASSOM, C. E. (1974). Modified opaque-2 corn endosperms. ll. Structure viewed with a scanning electron microscope. In American Association of Cereal Chemists, vol. 51, pp. 173–180. RODRIGUEZ-PULIDO, F. J. et al. (2012) Ripeness estimation of grape berries and seeds by image analysis. In Computers and Electronics in Agriculture, vol. 82, pp. 128–133. SCHINDELIN, J., RUEDEN, C. T., HINER, M. C., ELICEIRI, K. W. (2015) The ImageJ ecosystem: An open platform for biomedical image analysis. In Mol. Reprod. Dev., vol. 82, pp. 518–529. doi: https://doi.org/10.1002/mrd.22489 UCHIDA, S. (2013) Image processing and recognition for biological images. In Development, growth and differentiation, vol. 55, pp. 523–549. doi: https://doi.org/10.1111/dgd.12054 WATSON, S. A. (1987) Structure and composition. In WATSON, S. A. and RAMSTAD, P. E. (Eds.). Corn chemistry and technology. St. Paul: American Association of Cereal Chemists. WIWART M. et al. (2012) Identification of hybrids of spelt and wheat and their parental forms using shape and color descriptors. In Computers and Electronics in Agriculture, vol. 83, pp. 68–76. https://doi.org/10.1016/j.compag.2012.01.015

Seed coat and variety of peanut inhibits host preference and development of Oryzaephilus mercator

Oryzaephilus mercator (Fauvel) (Coleoptera: Silvanidae) is a postharvest pest of stored peanuts (Arachis hypogea L.). Although it is only a secondary pest, this insect causes extensive damage and reduces the quantity and quality of peanut kernels. The objective of this research was to study whether host preference and development of O. mercator differ depending on the variety of peanut and/or on whether the peanut retains its seed coat or is bare. We used three varieties of peanut (Kelinci, Bison and Takar1) separating out each variety into groups with or without a seed coat. In the laboratory, we conducted two separate studies examining host preference and development of O. mercator. Host preference was studied using a preference cage consisting of six chambers for all peanut varieties with and without seed coat and each cage contained 15 mating pairs of O. mercator. The development study was conducted by placing 15 mating pairs of O. mercator into a treatment jar and allowing them to feed on different peanut varieties with and without a seed coat. Results from the host preference study indicated that O. mercator preferred bare kernels of the Kelinci variety over other peanut varieties both as a food source and for oviposition. During the development experiment, we observed that O. mercator experienced faster development time when exposed to bare kernels of all three varieties tested as opposed to those with intact seed coat. Results show that peanuts with a seed coat and variety with high kernel hardness (Bison variety) deters predation and inhibits host preference and development of O. mercator.