Early Grain Research Articles

Variable water cycles have a greater impact on wheat growth and soil nitrogen response than constant watering

Current climate change models project that water availability will become more erratic in the future. With soil nitrogen (N) supply coupled to water availability, it is important to understand the combined effects of variable water and N supply on food crop plants (above- and below-ground). Here we present a study that precisely controls soil moisture and compares stable soil moisture contents with a controlled wetting-drying cycle. Our aim was to identify how changes in soil moisture and N concentration affect shoot-root biomass, N acquisition in wheat, and soil N cycling. Using a novel gravimetric platform allowing fine-scale control of soil moisture dynamics, a 3 × 3 factorial experiment was conducted on wheat plants subjected to three rates of N application (0, 25 and 75 mg N/kg soil) and three soil moisture regimes (two uniform treatments: 23.5 and 13% gravimetric moisture content (herein referred to as Well-watered and Reduced water, respectively), and a Variable treatment which cycled between the two). Plant biomass, soil N and microbial biomass carbon were measured at three developmental stages: tillering (Harvest 1), flowering (Harvest 2), and early grain milk development (Harvest 3). Reduced water supply encouraged root growth when combined with medium and high N. Plant growth was more responsive to N than the water treatments imposed, with a 15-fold increase in biomass between the high and no added N treatment plants. Both uniform soil water treatments resulted in similar plant biomass, while the Variable water treatment resulted in less biomass overall, suggesting wheat prefers consistency whether at a Well-watered or Reduced water level. Plants did not respond well to variable soil moisture, highlighting the need to understand plant adaptation and biomass allocation with resource limitation. This is particularly relevant to developing irrigation practices, but also in the design of water availability experiments.

Deeper roots associated with cooler canopies, higher normalized difference vegetation index, and greater yield in three wheat populations grown on stored soil water.

Simple and repeatable methods are needed to select for deep roots under field conditions. A large-scale field experiment was conducted to assess the association between canopy temperature (CT) measured by airborne thermography and rooting depth determined by the core-break method. Three wheat populations, C306×Westonia (CW), Hartog×Drysdale (HD), and Sundor×Songlen (SS), were grown on stored soil water in NSW Australia in 2017 (n=196-252). Cool and warm CT extremes ('tails') were cored after harvest (13-32% of each population). Rooting depth was significantly correlated with CT at late flowering (r= -0.25, -0.52, and -0.23 for CW, HD, and SS, respectively, P<0.05 hereafter), with normalized difference vegetation index (NDVI) at early grain filling (r=0.30-0.39), and with canopy height (r=0.23-0.48). The cool tails showed significantly deeper roots than the respective warm tails by 8.1 cm and 6.2 cm in CW and HD, and correspondingly, greater yields by an average 19% and 7%, respectively. This study highlighted that CT measured rapidly by airborne thermography or NDVI at early grain filling could be used to guide selection of lines with deeper roots to increase wheat yields. The remote measurement methods in this study were repeatable and high throughput, making them well suited to use in breeding programmes.

Justification of models of changing project environment for harvesting grain, oilseed and legume crops

An analysis of the condition of implementation of projects in agricultural production is carried out. The disadvantages of existing methods and models of planning of the content and time of execution of works in the projects, which mostly do not take into account the changing components of their project environment, are substantiated. The proposed methodology for justifying the models of a changing project environment for harvesting grain, oilseed and legume crops is based on the analysis of official statistics of agrometeorological stations and involves the implementation of production experiments, which makes it possible to increase the accuracy of the results. It has been established that the dewy periods of time in the projects for the collection of early oilseeds, cereals and legumes are characterized by a probabilistic distribution of the time of occurrence of dew and its duration. The indicated regularity and the established correlation relationship between the occurrence of dew and its duration are the main components of the model. The substantiated model of the pink period of time allows to take into account the changing events of the project environment and to improve the quality of the content management process and the time of performance of the harvesting work. It is established that the deficit of humidity in the air, in which the performance of harvesting is effective, changes over the course of the day by parabolic dependence. Its maximum value depends on the agrometeorologically acceptable duration of the works in the projects of harvesting early oilseeds, grain and legume crops, which is the basis for substantiating the model of the air humidity deficit and taking into account its impact on the implementation of works in these projects. The obtained results of the research are the basis of development of simulation models of projects for the collection of early oilseeds, grain and legume crops to improve the accuracy of determining the use indicators and resource requirements for the implementation of these projects. The obtained models increase the quality of management decision making in the projects of harvesting early oilseeds, grain and legume crops.

Metabolic responses of rice cultivars with different tolerance to combined drought and heat stress under field conditions.

BackgroundRice is susceptible to both drought and heat stress, in particular during flowering and grain filling, when both grain yield and quality may be severely compromised. However, under field conditions, these 2 stresses rarely occur separately. Under well-watered conditions, plants avoid heat stress by transpirational cooling, while this is not possible under drought conditions. Although investigating combined drought and heat stress is clearly more agronomically relevant than analyzing the effects of the single stresses, only a few studies of this stress combination, in particular under field conditions, have been published.ResultsThree rice cultivars differing in drought and heat tolerance were grown in the field under control and drought conditions in 3 consecutive years. Drought was applied either during flowering or during early grain filling and resulted in simultaneous heat stress, leading to reduced grain yield and quality. Analysis by gas chromatography−mass spectrometry showed distinct metabolic profiles for the 3 investigated organs (flag leaves, flowering spikelets, developing seeds). The metabolic stress responses of the plants also strongly differed between cultivars and organs. Correlation analysis identified potential metabolic markers for grain yield and quality under combined drought and heat stress from both stress-regulated metabolites and from metabolites with constitutive differences between the cultivars.ConclusionsGas chromatography−mass spectrometry resolved metabolic responses to combined drought and heat stress in different organs of field-grown rice. The metabolite profiles can be used to identify potential marker metabolites for yield stability and grain quality that are expected to improve breeding efforts towards developing rice cultivars that are resilient to climate change.

Detrital zircon trace elements from the Mesozoic Jiyuan Basin, central China and its implication on tectonic transition of the Qinling Orogenic Belt

AbstractThe Qinling Orogen and the Jiyuan Basin constitute a basin-mountain system during the Early Mesozoic. Therefore, sediments from the Jiyuan Basin can be used to deduce the orogenic process of the Qinling Orogen. This paper attempts to use detrital zircon trace elements with ages ranging from the Late Carboniferous to the Middle Triassic that were obtained from the Jiyuan Basin to discuss the tectonic evolution of Qinling Orogen. On the tectonic setting discriminating diagrams, most grains are concentrated in convergent continental margins/orogenic settings,whereas the remaining samples (268 Ma, 265Ma, 264 Ma and 254Ma) are plotted in anorogenic field. Compared to the Early Paleozoic (400-500Ma) zircons, 306Ma and 281Ma grains represent higher Th/ Nb ratios, which might be related to the Mianlve oceanic crust subduction. The lower Th/Nb ratios containing 268 Ma, 265Ma, 264 Ma and 254Ma grains might indicate lithospheric extension subsequently. The final continent-continent collision between South China and North China blocks took place after the Middle Triassic (242Ma).

Sowing date and sowing method influence on camelina cultivars grain yield, oil concentration, and biodiesel production

AbstractSowing date and sowing method can have a profound influence on the productivity of alternative crops like camelina in semiarid agroecosystems. The objective of this study was to determine the effects of sowing date, sowing method, and cultivar on morphology, phenology, grain yield, oil concentration, oil, and biodiesel production of camelina. A 2‐year study was carried out at the University of Nevada, Reno Main Station Field Laboratory, during the spring to early summer of 2016 and 2017. Treatments were two sowing dates (SD) of 18 March 2016 (early SD) and 17 April 2016 (late SD) in Year 1 and 11 April 2017 (early SD) and 11 May 2017 (late SD) in Year 2. The change in SD in the second year was due to the excessively wet field condition preventing land preparation and sowing. There were two sowing methods (SM) imposed (broadcast and drill) and three cultivars of camelina (Blaine Creek, Columbia, and Pronghorn) arranged in a 3 × 2 × 2 factorial in a randomized complete block design experiment with four replications. Responses were considered different if p &lt; 0.05. Grain yield of camelina was influenced by SD in Year 1 and SD × SM interaction in Year 2. In Year 1, grain yield was greater for early (921 kg/ha) compared to late SD (503 kg/ha, SE = 101). In Year 2, for early SD grain yield was not different between SM (average = 594 kg/ha), but for late, it was greater for drill (676 kg/ha) than broadcast (130 kg/ha, SE = 75). For broadcast SM, grain yield was greater for early (587 kg/ha) compared to late SD (130 kg/ha, SE = 75), but for drill SM, grain yield was not different between SD (average = 639 kg/ha). Oil concentration was affected by SD in both years, and in Year 1, for example, it was greater for early (295 g/kg) versus late SD (284 g/kg SE = 2.7). Both oil and biodiesel production followed a similar pattern to grain yield in this study. Based on the magnitude of differences observed in both years of this study, late SD and broadcast sowing are not viable options for farmers who want to venture into camelina production in Nevada.

Transcriptome analysis reveals important candidate genes involved in grain-size formation at the stage of grain enlargement in common wheat cultivar "Bainong 4199".

Grain-size is one of the yield components, and the first 14 days after pollination (DAP) is a crucial stage for wheat grain-size formation. To understand the mechanism of grain-size formation at the whole gene expression level and to identify the candidate genes related to grain pattern formation, cDNA libraries from immature grains of 5 DAP and 14 DAP were constructed. According to transcriptome analysis, a total of 12,555 new genes and 9,358 differentially expressed genes (DEGs) were obtained. In DEGs, 2,876, 3,357 and 3,125 genes were located on A, B and D subgenome respectively. 9,937 (79.15%) new genes and 9,059 (96.80%) DEGs were successfully annotated. For DEGs, 4,453 were up-regulated and 4,905 were down-regulated at 14 DAP. The Gene Ontology (GO) database indicated that most of the grain-size-related genes were in the same cluster. The Kyoto Encyclopedia of Genes and Genomes (KEGG) database analysis showed that 130, 129 and 20 DEGs were respectively involved in starch and sucrose metabolism, plant hormone signal transduction and ubiquitin-mediated proteolysis. Expression levels of 8 randomly selected genes were confirmed by qRT-PCR, which was consistent with the transcriptome data. The present database will help us understand the molecular mechanisms underlying early grain development and provide the foundation for increasing grain-size and yield in wheat breeding programs.

Discriminating post-silking environmental effects on starch composition in maize kernels

Maize (Zea mays L.) endosperms with high amylose proportion are harder and denser than endosperms with low amylose. Environmental conditions could affect amylose/starch ratio. The purpose of this work was to prove the effect of incident solar radiation, temperature, refertilization with nitrogen (N) and sulfur (S) and source/sink ratio during grain filling on maize amylose/starch ratio. The associations among changes in amylose/starch ratio and other grain components were also analyzed. We evaluated shading treatments in two periods during grain filling period. Fertilization treatments were evaluated by adding extra N and S per hectare in V15. Heating treatments were evaluated by increasing surface grain temperature during the grain filling period. Source/sink ratio was modified via defoliation and plant thinning. Variations in source/sink ratio or refertilization with N and S did not produce significant changes in starch composition. Increases in minimum temperature during early effective grain filling were related to decreases in starch percentage and to increases in amylose/starch ratio. Thus, future maize starch quality studies need to focus on thermal conditions during grain filling and on the metabolic steps involved. According to these results, management practices that imply a modification in temperature during the grain filling period affect starch composition.

Canada & Vietnam: Argex & Hung Thinh – TiO2 pigment

The objective of this study was to compare grain yield, nitrogen use efficiency (NUE) and stay-green traits in winter barley under low and high nitrogen (N) fertilization treatments. Field trials were conducted during two growing seasons in a southern Pannonian location (Novi Sad, Serbia) with fifteen six-rowed barley cultivars released between 1972 and 2013. The rate of genetic gain in grain yield was higher under high N level, indicating that modern barley cultivars use the applied N fertilizer more efficiently than older cultivars. The improvement in NUE and N uptake efficiency were positively related with year of cultivar release under both fertilization levels, while association between N utilization efficiency and year of cultivar release was significant at high N fertilization. Modern cultivars had higher normalized difference vegetation index (NDVI) values at the anthesis, start and mid senescence. Moreover, time to mid senescence was prolonged in modern cultivars, indicating slower N remobilization during early grain filling period. Values of NDVI at different senescence stages were more related to N uptake efficiency, while timing of senescence stages were in association with N utilization. Close association between NDVI values at different senescence stages and N uptake indicate that application of NDVI sensors could be used for identification of cultivars with improved N productivity.

Effects of improved practices on grain sorghum stalk borer and weeds: case studies from three regions of Ethiopia

We conducted three different on farm experiments in three major sorghum producing areas of Ethiopia to find solutions to major grain sorghum pests (weeds and stalk borer) prevailing in the respective areas. These were: 1) effect of integrated technologies to control grain sorghum stalk borer, 2) screening early maturing grain sorghum varieties that could tolerate stalk borer, and 3) weeding effect on sorghum yield. These experiments were conducted on farm and demonstrated to farmers in south Tigray, west Hararghe and south west Ethiopia, respectively. In south Tigray, we found that grain sorghum yield increased by 68% (5600 kg ha−1). Whereas, among the five varieties introduced in west Hararghe, Gedo variety outstripped, and gave the highest yield (2162 kg ha−1) but, notably, with the highest infestation of stalk borer. In southwest Ethiopia, about three-fold yield increment was obtained by hand-removing weeds and applying 100 kg ha −1 DAP and urea. Applied the same amount and types of fertilizers, but without removing the weeds, resulted in total crop failure because broad-leaved weeds might have competed for nutrients and light and suppressed the crop. We conclude that weeds and stalk borer are significantly reducing grain sorghum yield in the respective areas, but they can be managed with integrated approaches to potentially enhance sorghum grain yield.

High-throughput phenotyping platforms enhance genomic selection for wheat grain yield across populations and cycles in early stage.

Genomic selection (GS) models have been validated for many quantitative traits in wheat (Triticum aestivum L.) breeding. However, those models are mostly constrained within the same growing cycle and the extension of GS to the case of across cycles has been a challenge, mainly due to the low predictive accuracy resulting from two factors: reduced genetic relationships between different families and augmented environmental variances between cycles. Using the data collected from diverse field conditions at the International Wheat and Maize Improvement Center, we evaluated GS for grain yield in three elite yield trials across three wheat growing cycles. The objective of this project was to employ the secondary traits, canopy temperature, and green normalized difference vegetation index, which are closely associated with grain yield from high-throughput phenotyping platforms, to improve prediction accuracy for grain yield. The ability to predict grain yield was evaluated reciprocally across three cycles with or without secondary traits. Our results indicate that prediction accuracy increased by an average of 146% for grain yield across cycles with secondary traits. In addition, our results suggest that secondary traits phenotyped during wheat heading and early grain filling stages were optimal for enhancing the prediction accuracy for grain yield.

Modeling irrigation and nitrogen management of wheat in northern Ethiopia

Wheat (Triticum aestivum) is one of the most important staple food crops in Ethiopia. However, its production is limited by moisture and nutrient stresses. A field experiment was conducted in northern Ethiopia to: (i) evaluate the effects of irrigation and nitrogen (N) and phosphorus (P) fertilizer application rates on yield, biomass and irrigation water productivity (IWP) of wheat; (ii) calibrate and validate a crop model for simulating yield and biomass of wheat under different levels of nitrogen and irrigation applications; (iii) evaluate consecutive above-ground biomass accumulation as affected by different combinations of irrigation and N fertilizer rates. The Decision Support for Agro technology Transfer Cropping System Model (DSSAT-CSM) was calibrated and validated with experimental data. The calibrated and validated DSSAT-CSM was used to simulate wheat biomass, yield, and irrigation water productivity under rainfed and three irrigation scenarios: I0, rainfed; DI1, two irrigations from heading to flowering; DI2, four irrigations from heading to early grain filling; and DI3, six irrigations from heading to mid grain filling period in combination with nine N rates (0, 16, 32, 64, 80, 96, 112, 128 and 160 kg/ha). Simulation results showed that both irrigation and nitrogen applications positively affected wheat yield, biomass and IWP. Much of the increase in biomass and yield was due to increased N than to increased irrigation. Yield increased with increase in N application rates, however, at a diminishing rate yielding a curvilinear relationship. Four irrigation (DI2) starting from heading to early grain filling stage resulted in a yield similar to DI3, six irrigation applications from heading to mid grain filling stage. Simulations showed that two irrigation applications strategy (DI1) yielded relatively higher IWP (1.8 kg/m3) at the highest application rate of 160 kg N/ha. Further economic analysis would help to identify most efficient practices for wheat production in northern Ethiopia.

Assessment of breeding programs sustainability: application of phenotypic and genomic indicators to a North European grain maize program.

We review and propose easily implemented and affordable indicators to assess the genetic diversity and the potential of a breeding population and propose solutions for its long-term management. Successful plant breeding programs rely on balanced efforts between short-term goals to develop competitive cultivars and long-term goals to improve and maintain diversity in the genetic pool. Indicators of the sustainability of response to selection in breeding pools are of key importance in this context. We reviewed and proposed sets of indicators based on temporal phenotypic and genotypic data and applied them on an early maize grain program implying two breeding pools (Dent and Flint) selected in a reciprocal manner. Both breeding populations showed a significant positive genetic gain summing up to 1.43qx/ha/year but contrasted evolutions of genetic variance. Advances in high-throughput genotyping permitted the identification of regions of low diversity, mainly localized in pericentromeric regions. Observed changes in genetic diversity were multiple, reflecting a complex breeding system. We estimated the impact of linkage disequilibrium (LD) and of allelic diversity on the additive genetic variance at a genome-wide and chromosome-wide scale. Consistently with theoretical expectation under directional selection, we found a negative contribution of LD to genetic variance, which was unevenly distributed between chromosomes. This suggests different chromosome selection histories and underlines the interest to recombine specific chromosome regions. All three sets of indicators valorize in house data and are easy to implement in the era of genomic selection in every breeding program.

Heat stress alters chlorophyll fluorescence, photosynthesis and antioxidative enzyme activities in wheat cultivars

Heat stress becomes one of the most limiting factors to crop growth and yield. To investigate the impact of heat stress on physiological and biochemical responses in wheat cultivars, a pot experiment was conducted in the Depart- ment of Crop Botany, Bangladesh Agricultural University in Mymensingh, during November 2016 to March 2017. The experiment was laid out in a two factorial CRD design with three replications. The factors were (i) four wheat cultivars (BARI GOM-25, BARI GOM-26, BARI GOM-27 and BARI GOM-28) and (ii) heat stress (control and heat). The heat stress (38/25 °C day/night) was imposed to the wheat plants for three days at early grain filling stage in a climate chamber. The control plants were remained in the field at around 20−25 °C. Heat stress declined the leaf greenness (SPAD), the maximum photochemical efficiency of PSII (Fv/Fm), photosynthesis rate (A) and grain weight in all the cultivars in comparison to control. The leaf greenness (SPAD) and Fv/Fm were declined with the progress of heat stress treatment in all four cultivars. In both cases, lowest reduction was observed in BARI GOM-28 whereas, the highest reduction in SPAD and Fv/Fm were observed in BARI GOM-26 and BARI GOM-27, respectively. The percent reductions in photosynthesis and grain weight were significantly higher in BARI GOM-28 in comparison to other cultivars. Increased activities of catalase, peroxidase and ascorbate peroxidase enzymes were observed under heat stress in all four cultivars. Therefore, it may be concluded that the cultivar BARI GOM-28 showed more tolerance to heat stress than the other cultivars based on the measured physiological and biochemical traits.

Genotypic variation in whole-plant transpiration efficiency in sorghum only partly aligns with variation in stomatal conductance.

Water scarcity can limit sorghum (Sorghum bicolor (L.) Moench) production in dryland agriculture, but increased whole-plant transpiration efficiency (TEwp, biomass production per unit of water transpired) can enhance grain yield in such conditions. The objectives of this study were to quantify variation in TEwp for 27 sorghum genotypes and explore the linkages of this variation to responses of the underpinning leaf-level processes to environmental conditions. Individual plants were grown in large lysimeters in two well-watered experiments. Whole-plant transpiration per unit of green leaf area (TGLA) was monitored continuously and stomatal conductance and maximum photosynthetic capacity were measured during sunny conditions on recently expanded leaves. Leaf chlorophyll measurements of the upper five leaves of the main shoot were conducted during early grain filling. TEwp was determined at harvest. The results showed that diurnal patterns in TGLA were determined by vapour pressure deficit (VPD) and by the response of whole-plant conductance to radiation and VPD. Significant genotypic variation in the response of TGLA to VPD occurred and was related to genotypic differences in stomatal conductance. However, variation in TGLA explained only part of the variation in TEwp, with some of the residual variation explained by leaf chlorophyll readings, which were a reflection of photosynthetic capacity. Genotypes with different genetic background often differed in TEwp, TGLA and leaf chlorophyll, indicating potential differences in photosynthetic capacity among these groups. Observed differences in TEwp and its component traits can affect adaptation to drought stress.

Early Wheat Harvest Influenced Grain Quality and Profit but Not Yield

Early Wheat Harvest Influenced Grain Quality and Profit but Not Yield

Early prediction of wheat grain yield production from root-zone soil water content at heading using Crop RS-Met

Wheat production in drylands is determined greatly by the available water at the critical growth stages. In dry years, farmers usually face the dilemma of whether to harvest at an early stage for hay or silage, with reduced profit, or leave the crop for grain production with the risk of a major economic loss. Thus, an early prediction of potential wheat grain yield production is essential for agricultural decision making, particularly in water-limited areas.Here, we test whether using a proximal-based biophysical model of actual evapotranspiration (water use) and root-zone soil water content (SWC) – Crop RS-Met – may assist in providing early grain yield predictions in dryland wheat fields. Crop RS-Met was examined in eight experimental fields comprising a variety of spring wheat (Triticum aestivum L.) cultivars exposed to different treatments and amounts of water supply (185 mm - 450 mm). Crop RS-Met was first validated against SWC measurements at the root-zone profile. Then, modeled SWC at heading (SWCHeading) was regressed against end-of-season grain yields (GYEOS), which ranged from 1.30 tons ha−1 to 7.12 tons ha−1, for a total of 56 treatment blocks in 4 seasonal years (2014–2017).Results show that Crop RS-Met accurately reproduce seasonal changes in SWC with an average R2 of 0.89 ± 0.05 and RMSE and bias of 0.014 ± 0.004 m3 m−3 and -0.002 ± 0.004 m3 m−3, respectively. Modeled SWCHeading showed high and significant positive linear relationship with GYEOS (GYEOS[tons ha-1] = 0.080×SWCHeading[mm] - 5.387; R2 = 0.90; P < 0.001; N=56). Moreover, Crop RS-Met showed to be capable of accurately predicting GYEOS even in cases where water supply and grain yield had adverse relationships. Aggregating results to the field-scale level and classifying fields per water supply conditions resulted in an even stronger linear relationship (R2 = 0.94; P < 0.001; N=9). We conclude that Crop RS-Met may be used to predict GYEOS at heading in dryland fields for possible use by farmers in decision making at critical wheat growth stages.

Interactive effect of planting date and fertiliser application on maize growth and yield under dryland conditions

Understanding the relationships among management practices during planting period will help producers to improve crop production under climate change. The interaction of planting date and soil fertility on maize yield was evaluated. Field trials were conducted during summer in 2014/15 and 2015/16 at the University of KwaZulu-Natal research farm, Pietermaritzburg, South Africa. A split-plot design was used with planting date and soil fertility as main and subplots, respectively, replicated four times. The interaction between planting date and fertility level significantly influenced plant growth and physiological parameters. The highest plant growth and physiological responses occurred in early- and mid-season planted maize during 2014/15 and 2015/16, respectively. Early planting favoured crop growth, grain yield and yield components during 2014/15 (warm season), while mid planting was the best during 2015/16 (dry season). Optimal fertiliser application has economic benefits to the farmer where it is led to increase productivity at early- and mid-planting dates during warm (2014/15) and dry (2015/16) seasons, respectively. However, optimal fertiliser application only improved plant photosynthetic activity under adequate rainfall and temperature, while minimal application of fertiliser gave higher yield returns with a mid-planting date. Longer-term experiments are needed to validate the recommendations from the current study.

New insights into the evolution of wheat avenin-like proteins in wild emmer wheat (Triticum dicoccoides)

Fifteen full-length wheat grain avenin-like protein coding genes (TaALP) were identified on chromosome arms 7AS, 4AL, and 7DS of bread wheat with each containing five genes. Besides the a- and b-type ALPs, a c type was identified in the current paper. Both a and b types have two subunits, named x and y types. The five genes on each of the three chromosome arms consisted of two x-type genes, two y-type genes, and one c-type gene. The a-type genes were typically of 520 bp in length, whereas the b types were of 850 bp in length, and the c type was of 470 bp in length. The ALP gene transcript levels were significantly up-regulated in Blumeria graminis f. sp. tritici (Bgt)-infected wheat grain caryopsis at early grain filling. Wild emmer wheat [(WEW), Triticum dicoccoides] populations were focused on in our paper to identify allelic variations of ALP genes and to study the influence of natural selection on certain alleles. Consequently, 25 alleles were identified for TdALP-bx-7AS, 13 alleles were identified for TdALP-ax-7AS, 7 alleles were identified for TdALP-ay-7AS, and 4 alleles were identified for TdALP-ax-4AL Correlation studies on TdALP gene diversity and ecological stresses suggested that environmental factors contribute to the ALP polymorphism formation in WEW. Many allelic variants of ALPs in the endosperm of WEW are not present in bread wheat and therefore could be utilized in breeding bread wheat varieties for better quality and elite plant defense characteristics.

Performance Evaluation of Malt Barley: from Malting Quality and Breeding Perspective

Lack of suitable malt barley varieties that exhibit high yielding, stable performance, and good malting quality is the major factor among several production constraints contributing to low productivity of malt barley in the North Gondar Zone. The present study was done to evaluate and recommend the best performing varieties in the major potential areas of North Gondar. The experiment was conducted at three locations for two consecutive years (2015 and 2016) during the main cropping season using twelve improved varieties. The design was randomized complete block design with three replications. Analysis of variance and GGE [genotype main effect (G) and genotype-by-environment interaction (GE)] biplot analysis were conducted following their respective procedures. Combined analysis of variance revealed a highly significant difference (P < 0.01) among genotypes, environments, and genotype-by-environment interaction for grain yield, most agronomic and malt quality traits. All the varieties had acceptable malt quality traits. The variety IBON-174/03 was found to be the highest yielding and the most stable variety across environments. According to the polygon view of biplot analysis, the varieties were spread across four sections and the test environments spread across two sections. Among the six test environments, D and C were more discriminating and F and B were less discriminating. Test environments F, E, and A were found to be more representative of the mega-environment than D. Considering early maturity, malt quality, grain yield, and stability performance; it is recommended to use the variety IBON-174/03 for production in the study areas and in similar areas.