Advanced Wheat Research Articles

Estimation of Genetic Parameters in Bread Wheat (Triticum aestivum L.) Genotypes Evaluated Under High Temperature Yield Trial in Ethiopia

The study was carried out to estimate genetic parameters of 49 bread wheat genotypes and standard check evaluated at Kulumsa and Melkasa using alpha lattice design with two replications. The analysis of variance result showed highly significant differences among the genotypes for all traits (P< 0.001), implying the presence of considerable genetic variability for these traits. Out of 50 genotypes, four genotypes such as EBW2113062, EBW2113039, EBW2113037 and EBW2113056 were the top yielding genotypes across the locations. Furthermore, 30 of the 50 genotypes gave grain yield above grand mean whereas 14 genotypes had grain yield above the check, Dursa(1295.05kg/ha). In the other word, about 60% of genotypes were with mean grain yield above the overall mean and 30% of them provided mean grain yield above the check, Dursa, variety. High and moderate heritability estimates were found for most of traits showing that the variation observed was mainly under genetic control. The highest PCV and GCV values were observed for grain yield at both locations indicating better opportunity for improvement in this trait via selection. The phenotypic coefficient of variation (PCV) was generally higher than the genotypic coefficient of variation (GCV) for all characters at both locations. The difference between PCV and GCV was large in TKW followed by PHT and Grain yield indicating that these traits are influenced by the environment. However, differences between them were small for most of the traits indicating low effect of environment on the expression of characters at both locations. The genotypic correlations between grain yield with thousand kernel weights and hectoliter weight were highly significant showing their important contribution to grain yield. Therefore, the identified genotypes with better performance could be utilized in advanced bread wheat yield trial targeted for high temperature condition in the country.

Seedling and Adult Plant Resistance Against Powdery Mildew and Yellow Rust in Indian Advanced Wheat Breeding Material and Commercial Genotypes

Seedling and Adult Plant Resistance Against Powdery Mildew and Yellow Rust in Indian Advanced Wheat Breeding Material and Commercial Genotypes

Graphical Analysis of Multi-environmental Trials for Bread Wheat (Triticum aestivum L.) Grain Yield Based on GGE Bi-Plot Analysis

Bread wheat (Triticum aestivum L.) is a crucial crop in Ethiopia, and breeders test newly developed elite lines for superiority to existing cultivars to boost national productivity. The study was undertaken during the 2021–22 to 2022–23 cropping seasons at seven environments in optimum moisture areas of Ethiopian using 36 diverse and advanced bread wheat genotypes to evaluate the GEI by the graphical method of GGE biplot and to identify the genotypes with high mean yield performance and stability. Field experiments were conducted at the Adet, Asasa, Kulumsa, and Sinana research centers in Ethiopia. The experiments were planted in an alpha lattice design replicated three times in six rows of 2.5m long. Row-to-row distance and distance between blocks were 0.2m and 1.5m, respectively. The analysis of variance revealed that genotype, environment, and their interaction showed a highly significant effect on the yield as reflected in the GGE model and the GGE model indicated the suitability of the genotypes EBW202136 (33), Boru (1), and EBW202172 (12), with high mean yield and stability, whereas the genotypes EBW202185 (16) and Deka (36) produced high mean yield, but unstable. Likewise, the genotypes EBW202164 (27) and EBW202192 (29) produced low mean yield and unstable. The AMMI analysis of variance for grain yield across the environments showed that 17.26% of the total variation was attributed to genotypic effects, 64.03% to environmental effects, and 18.71% to GEI effects. Two mega environments were identified based on GGE biplot analysis and the which-won–model indicated the adaptation of genotypes Boru (1), EBW202159 (4), EBW202172 (12), EBW202171 (19), and EBW202136 (33) to first mega-environment and genotypes EBW202157 (3), EBW202166 (5), EBW202160 (6), EBW202162 (9), EBW202185 (16), Dursa (17) and Deka (36) in the second. These approaches allowed the identification of stable and high-yielding genotypes (EBW202136 (33) and EBW202172 (12)) which can be included in the national verification program, with a plan to release a new variety, and other genotypes with high yield could be utilized in breeding programs to further improve grain yield in bread wheat.

Identification of Climate-Smart Bread Wheat (Triticum aestivum L.) Germplasm for Optimum Moisture Areas of Ethiopia

Ethiopia's Bread Wheat Breeding Program conducts annual multi-environment yield trials to develop advanced wheat genotypes for Ethiopian wheat cultivation, ensuring a steady supply of new and improved varieties to meet production and marketing challenges. The objective of this research was to assess potential yield and the interactions between genotype and environment in wheat across multiple environments, as every cultivar has a distinct response to soil and climate. The BLUP analysis reveals that the 22AA and 22KU trials in 2022, along with 21KU trials in 2021 yielded high grain production, indicating optimal testing locations for distinguishing bread wheat genotypes and agroecologies. The study found that seven out of sixteen trials exhibited a higher genetic variance for yield, indicating high genotype discriminating power, with estimates ranging from 0.043 to 0.989 for genetic variance, 0.084 to 1.147 for error variance, and 72.7 to 96.4 for heritability. EBW202471 and EBW202473 are stable genotypes with good yield performance across correlated locations, with EBW202471 showing the highest yield (4.98 t/ha) and Deka showing a lower yield (4.07 t/ha). Three wheat genotypes, EBW202471, EBW202472, and EBW202473, were found to be moderately resistant to moderately susceptible to stem and yellow rust among 20 wheat genotypes. Finally, the two genotypes, EBW202471 and EBW202473, were advanced to National Performance Trials to evaluate their performance alongside top genotypes from regional federal research centers and to be released as new varieties.

Performance of durum wheat cultivars and advanced lines to black point under natural conditions in two crop seasons

Twenty seven advanced durum wheat lines and cultivars CIRNO C2008, Baroyeca Oro C2013, and Quetchehueca Oro C2013 were evaluated for their reaction to black point, under natural conditions at the Norman E. Borlaug Experimental Station, in the Yaqui Valley, Sonora, Mexico, during crop seasons 2015-2016 and 2016-2017. Sowing dates were November 12 and 19, 2015, for the first season, and November 17 and 24, 2016 for the second one, using 8 g of seed for a 0.7 m bed with two rows without replications. Harvest was done manually and the evaluation by visual inspection counting the number of healthy and infected grains in ten spikes per line/cultivar, in order to determine the percentage of infection. Based on the average of the two dates, in the first season one line did not show any infected grain, ten fell within the 0.1-2.5 % infection category, six within 2.6-5.0 %, three within 5.1-10.0 %, and seven within 10.1-30 %. Quetchehueca Oro C2013 did not show any infected grain, while CIRNO C2008 and Baroyeca Oro C2013 showed 1.7 and 12.3 % infection, respectively. In the second season, two lines did not show infected grains, seventeen lines and the three cultivars with 2.4, 1.5, and 1.0 %, respectively, fell within the 0.1-2.5 % infection category, six within 2.6-5.0 %, and two within 5.1-10.0 %. Lines with the highest percentage of infection were: 1A.1D5+1-06/3*MOJO//RCOL/4/ ARMENT//SRN_3/NIGRIS_4/3/CANELO_9.1/5/CF4-JS40//SOOTY_9/RASCON_37/4/CNDO/PRIMADUR//HAI-OU_17 /3/SNITAN/9/CBC509CHILE/6/ECO/CMH76A.722//BIT/3/ALTAR84/4/AJAIA_2/5/KJOVE_1/7/AJAIA_12/ F3LOCAL(SEL.ETHIO.135.85)//PLATA_13/8/S with 50.4 % in the first date of the first season, and WBDTBO/10/ PLATA_10/6/MQUE/4/USDA573//QFN/AA_7/3/ALBA-D/5/AVO/HUI/7/PLATA_13/8/THKNEE_11/9/CHEN/ ALTAR84/3/HUI/POC//BUB/RUFO/4/FNFOOT/11/MÂALI/10/ALTAR84/CMH82A.1062//ALTAR 84/3/YAZI_10/4/ SNITAN/9/USDA595/3/D67.3/RABI//CRA/4/ ALO/5/HUI/YAV_1/6/ARDENTE with 16.3 % in the second date of the second season. Higher infection was detected in crop season 2015-2016 possibly to the occurrence of higher relative humidity during grain expansion.

Performance of bread wheat advanced lines under late sowing and reduced irrigation

Twenty eight advanced wheat lines and cultivar Borlaug 100 were sown on January 15 and 30, 2020, at the Norman E. Borlaug Experimental Station, in the Yaqui Valley, Sonora, México. Plots consisted of 1 bed 2 m long with two rows and 0.80 m apart with two replications, a seed density of 100 kg ha-1 with two complementary irrigations. Average daily temperature (°C), maximum, minimum, relative humidity, rainfall, heat and cold units were recorded from January 1 to May 15, 2020. The average days for heading of the group was 67 for the first sowing date and 64 for the second, while days for physiological maturity were 103 and 95, respectively. The average plant height of the group for the first and second sowing dates was 83 cm; line SOKOLL/3/PASTOR//HXL7573/2*BAU/4/PARUS/ PASTOR/5/PIHA// WORRAKATTA/2*PASTOR/3/PRL/2*PASTOR consistently reached the maximum height with 92.5 and 95 cm in the first and second dates, respectively. The average a thousand grain weight of the group was 53.8 g for the first sowing date and 43.8 for the second; sister line SOKOLL/3/PASTOR//HXL7573/2*BAU/4/ SOKOLL/WBLL1/5/PIHA// WORRAKATTA/2*PASTOR/3/PRL/2*PASTOR (PTSS14Y00057S-0B-099Y-099B-43Y-020Y) showed the highest average weight with 57.07 g. The average grain yield per plot was 340 g; sister line WBLL4//OAX93.24.35/WBLL1 /5/CROC_1/AE.SQUARROSA(205)//BORL95/3/PRL/SARA//TSI/VEE#5/4/FRET2/6/D67.2/PARANA66.270//AE.SQUARROSA(320)/3/CUNNINGHAM/4/VORB (PTSS15Y00024S-099B-099Y-099M-10Y-020Y) showed the highest yield with 420 g which was above 5 t ha-1. The average temperature was 19.09 °C with a maximum of 36.3 °C and a minimum of 1.04 °C, and the number of heat and cold units was 229 and 227, respectively.

Discovering novel genomic regions explaining adaptation of bread wheat to conservation agriculture through GWAS

To sustainably increase wheat yield to meet the growing world population’s food demand in the face of climate change, Conservation Agriculture (CA) is a promising approach. Still, there is a lack of genomic studies investigating the genetic basis of crop adaptation to CA. To dissect the genetic architecture of 19 morpho-physiological traits that could be involved in the enhanced adaptation and performance of genotypes under CA, we performed GWAS to identify MTAs under four contrasting production regimes viz., conventional tillage timely sown (CTTS), conservation agriculture timely sown (CATS), conventional tillage late sown (CTLS) and conservation agriculture late sown (CALS) using an association panel of 183 advanced wheat breeding lines along with 5 checks. Traits like Phi2 (Quantum yield of photosystem II; CATS:0.37, CALS: 0.31), RC (Relative chlorophyll content; CATS:55.51, CALS: 54.47) and PS1 (Active photosystem I centers; CATS:2.45, CALS: 2.23) have higher mean values in CA compared to CT under both sowing times. GWAS identified 80 MTAs for the studied traits across four production environments. The phenotypic variation explained (PVE) by these QTNs ranged from 2.15 to 40.22%. Gene annotation provided highly informative SNPs associated with Phi2, NPQ (Quantum yield of non-photochemical quenching), PS1, and RC which were linked with genes that play crucial roles in the physiological adaptation under both CA and CT. A highly significant SNP AX94651261 (9.43% PVE) was identified to be associated with Phi2, while two SNP markers AX94730536 (30.90% PVE) and AX94683305 (16.99% PVE) were associated with NPQ. Identified QTNs upon validation can be used in marker-assisted breeding programs to develop CA adaptive genotypes.

Performance evaluation of advanced durum wheat genotypes under irrigated condition at Bhairahawa, Nepal

A field research was carried out at the National Wheat Research Program (NWRP) in Bhairahawa, Nepal in 2022 to investigate elite durum wheat genotypes and key traits contributing to grain yield. The experiment was performed in an alpha lattice design with two replications. Thirty distinct durum wheat genotypes were assessed, focusing on fourteen quantitative traits including days to booting, days to heading, days to maturity, plant height, spike length, peduncle length, number of tillers per square meter, number of spikes per square meter, number of grains per spike, grain weight per spike, thousand kernel weight, grain yield, biomass yield, chlorophyll content. The studied genotypes were grown under irrigated condition. Genotype NL1779 attained the highest grain yield of 3828 kg/ha, followed by NL1769 (3784 kg/ha), NL1772 (3726 kg/ha), NL1789 (3640 kg/ha) and NL1784 (3570 kg/ha). Principal components analysis revealed that eight traits were the major loadings on the first two principal components that describe 53.4% of the total morphological variance at irrigated condition. Cluster analysis grouped the different genotypes into four clusters, with each cluster showing variation in performance for different traits under irrigated conditions. Cluster III is characterized by genotypes exhibiting the highest grain yield, biomass yield, spike length, number of grains per spike, and number of spikes per square meter. Notably, the high-yielding genotypes NL1779, NL1769, NL1772, NL1789, NL1784, and NL1773 identified within this cluster could serve as potential candidates for inclusion in the national breeding program. These superior genotypes could be recommended for irrigated environment after further evaluation. Integrating them into national breeding programs offers an opportunity for genetic improvement, contributing to establishing a robust durum wheat production system in Nepal, meeting the growing demand for durum wheat products while promoting dietary diversity and sustainable agriculture.

Evaluation of anthocyanin-enriched wheat varieties (black, blue, purple) for enhanced antioxidant content and premium biscuit quality

The anthocyanin-enriched wheat varieties were explored for their health benefits and development of antioxidant-rich biscuits. In the present study, around 35 advanced lines, showcasing different colors (7 white, 9 purple, 11 black, 8 blue), and robust yield potential under local climatic conditions were selected. The wheat lines were screened for yield, grain hardness, protein, dough quality, biscuit baking and sensory quality attributes. The two advanced black wheat lines (black-1 and black-6) showed low grain hardness indices (49.8 and 32.4) and protein content (9.1 and 8.2%). The dough obtained from these wheat lines exhibited excellent parameters including low hardness and high springiness. The black-1 (soft texture) and black-6 (very soft texture) lines exhibited superior biscuit-making quality with a high spread ratio (13.2 and 14), mirroring the positive controls {white-6 (vs)-15}, and surpassing the average (8.9) and negative controls {white-C3 (7.7) and white-C4 (8.4)}. Despite a reduction in anthocyanin content during baking, both lines demonstrated a 1.3-fold higher antioxidant activity compared to the control. These black wheat lines present significant potential for commercialization, offering an avenue to enhance the quality and nutritional profile of biscuits in the food industry.

Divergence Assessment of Advanced Bread Wheat Lines under Contrasting Heat Stress Regimes Utilizing Stress Tolerance Indices

Heat stress during the post-anthesis phase significantly impacts wheat cultivation. To evaluate the tolerance of advanced wheat lines to heat stress, stress tolerance indices were used under both normal and post-anthesis heat stress conditions. The results showed a decrease in the average yield of advanced lines under both conditions, indicating the negative impact of heat stress on wheat cultivation. The analysis using PCs, biplot, and ranked clusters revealed that line V-21448 had below-average values for RHSI and %YDR, while V-21243 had values close to the average and all other lines had above-average values. Additionally, under normal conditions, V-19532 had the highest values for RHSI and HYT 100-47 had the lowest values for %YDR. In heat stress conditions, HYT 100-47 had the lowest values for both indices. HYT 100-74 and HYT 100-76 had the highest average values for MNP and YDI and were highly stable in the heat environment. Under normal settings, YDI, RHSI, and % YDR showed a positive correlation, while under heat stress conditions, the same traits showed a negative correlation. MNP had a high positive correlation with Yp and Ys, while YDSI had a negative correlation with Yp but a positive correlation with Ys. These results suggest that these traits are useful for identifying advanced lines with increased yield under both conditions.

Evaluation of elite spring wheat genotypes for grain yield and other agronomic attributes in hills of Sudurpaschim Province, Nepal

Selection and release of high yielding and disease resistant varieties is the cost effective and ecologically sound approach for increasing the production and productivity of agricultural crop in Nepal. Twenty-two advanced bread wheat (Triticum aestivum L.) genotypes including commercial check variety "Sorgadwari", newly released check variety "Khumal Shakti" and Local Check variety " Jhadde" were evaluated under irrigated conditions at Gokuleshwor Agriculture and Animal Science College (GAASC), Baitadi, Nepal during 2022/2023. This study was carried out for the identification of high yielding genotypes under irrigated condition in western hills. The experiment was conducted in Alpha lattice design with two replications. The highly significant difference (p<0.01) among the genotypes was found for most of the traits viz., days to heading, days to anthesis, days to maturity, plant height, spikes per square meter, number of grains per spike, grain weight per spike, flag leaf area, thousand kernel weight, biomass yield and grain yield and non-significant difference for spike length. The mean grain yield ranged from 1908 to 4146 kg/ha with grand mean of 2766 kg/ha. The highest grain yield was produced by genotype NL 1474 (4146 kg/ha) which was followed by NL 1475 (3994 kg/ha), NL1597 (3536 kg/ha) and NL 1590 (3070 kg/ha). The check variety Sorgadwari and Khumal Shakti produced 3480 and 3070 kg/ha respectively while the local check variety Jhadde produced 2655 kg/ha. Similarly, highest TKW was produced by NL 1487 (68.5 g) followed by BL 5148 (67.2 g) and WK 3730 (66.3 g). The correlation analysis revealed that grain yield showed highly significant positive correlation with biomass yield (0.90**) and number of grains per spike (0.6**), spikes per square meter (0.7**), plant height (0.5**) and non-significant positive correlation with spike length (0.21) and grain weight per spike (0.1) and non-significant negative correlation with days to heading (-0.2) and days to maturity (-0.2). Cluster analysis revealed that Cluster III consists of 4 genotypes namely NL 1474, NL 1475, NL 1597 and Sorgadwari. This cluster represent with highest grain yield, number of spikes per meter square, number of grains per spike and grain weight per spike. Among the tested genotypes, NL 1474, NL 1475, NL 1597 and NL 1590 were found superior for grain yield and yield-related traits in comparison to three checks and could be recommended for hills of Sudurpaschim province after further testing in multi-environment and in farmer's field.

Genome wide association study and genomic prediction for stripe rust resistance at the seedling stage in advanced spring bread wheat genotypes of ICARDA Morocco

One of the most devastating diseases impacting wheat (Triticum aestivum L.) worldwide is stripe rust, which is propagated by Puccinia striiformis f. Sp. Tritici (Pst). The development and utilization of resistant cultivars offer an effective and eco-friendly approach to manage this disease. However, the emergence of new virulent strains of Pst, driven by continuous mutations within the pathogen, rapidly undermines the effectiveness of existing resistance genes. This necessitates the ongoing identification and incorporation of new resistance genes to breed wheat varieties that can maintain resistance against evolving strains of the pathogen. A genome-wide association study (GWAS) and genomic prediction (GP) were conducted using yellow rust data from the seedling stage under controlled conditions, involving 200 elite bread wheat genotypes and 13,151 SNP markers. GWAS analysis identified fourteen SNP markers significantly associated with yellow rust resistance, using a general linear model (GLM). The markers (wsnp Ex c1085 2078944, wsnp Ku c3682 6,786,230) on chromosome 1D and (wsnp Ex c8240 13,914,674) on chromosome 3A were notably correlated with seedling-level resistance to yellow rust. Additionally, the marker 'AX-94703603′ on chromosome 3A, which recorded the highest -Log10(p) value, was linked to the gene 'TraesCS3A02G335300' encoding the protein kinase domain. These markers, after validation, could be utilized for gene pyramiding in wheat breeding programs to enhance rust resistance through marker-assisted selection.

Deciphering Genetic Diversity in Advanced Wheat Lines (Triticum aestivum L.) for Yield and Other Yield Contributing Traits Across the Locations

Twenty advanced wheat genotypes were evaluated for yield and yield-contributing traits in six field trials over two cropping seasons (Rabi 2020-21 and 2021-22) using a completely randomized block design (RBD) at two locations: the N.E. Borlaug Crop Research Centre (NEBCRC), G.B.P.U.A&T, Pantnagar, U.S. Nagar district, and the Agriculture Research Center Majhera, Nainital, Uttarakhand. The study aimed to assess genetic diversity among the genotypes via principal component analysis (PCA) and cluster analysis, offering insights into genetic variations. Three clusters were formed, with the maximum number of genotypes occurring in the second cluster. A lower p-value indicates that the clusters are statistically significant, suggesting that the observed diversity is not random. High estimates of cophenetic distance (.79) specify a high genetic distance between clusters, indicating that diverse genetic material is under study. The maximum genetic distance observed was 144.9 between genotypes G5 and G11. These findings suggest that these two genotypes are the most genetically diverse among all the studied genotypes and can be used as parents to develop high genetic variation in the studied traits. The PCA results yielded 18 principal components, with the first seven components accounting for approximately 83% of the total variance, indicating significant genetic diversity. The scree plot affirmed the robustness of the study’s results by suggesting that the first eight principal components accounted for a substantial portion of the variance.The findings of current study could be exploited in planning and execution of future breeding programme in wheat.

Performance of bread wheat advanced lines under late sowing

Thirty two advanced wheat lines which included four groups of sister lines and the commercial bread wheat cultivar Borlaug 100 were sown on January 16 and 30, 2019, at the Norman E. Borlaug Experimental Station, in the Yaqui Valley, Sonora, Mexico. Plots consisted of 1 bed 2 m long with two rows and 0.80 m apart without replications, and a seed density of 100 kg ha-1. Average daily temperature (°C), maximum, minimum, relative humidity, rainfall, heat and cold units were recorded from January 1 to May 15, 2019. The variables evaluated were: days to heading, plant height (cm), and grain weight in 20 spikes (g). The average days for heading of lines was 76 for the first sowing date and 73 for the second. The average plant height of the group for the first sowing date was 95 cm and 88 for the second; line W15.92/4/PASTOR//HXL7573/2*BAU/3/WBLL1/5/OAX92.2.5/6/BABAX/LR42//BABAX/3/ ER2000 was the tallest in the first date with 120 cm and with 115 in the second date. The average grain weight of the group in 20 spikes in the first sowing date was 55 g and 40.9 in the second; the line MEX94.15.34/4/PASTOR//HXL7573/2*BAU/3/WBLL1/5/ BABAX/LR42//BABAX/3/ER2000 showed the highest weight in the first and second dates with 71.1 g and 49.5, respectively. In the first date, the line W15.92/4/PASTOR//HXL7573/2*BAU/3/WBLL1/5/IWA8612414/6/BABAX/ LR42//BABAX/3/ER2000 showed the lowest grain weight in 20 spikes with 41.0 g, while in the second date, the sister line PBL94.14.30/4/PASTOR//HXL7573/2*BAU/3/WBLL1/5/BABAX/LR42//BABAX/3/ER2000 (PTSS12SHB 00003T-0TOPB-099Y-099B-7Y-020Y-0B) showed 25.6 g. The average temperature was 18.26 °C with a maximum of 35.2 °C and a minimum of 3.6 °C; the average relative humidity was 67.0 %; there were 13.1 mm of precipitation, and the number of heat and cold units was 146 and 293, respectively.

Mapping of a Recessive Gene for All-Stage Resistance to Stripe Rust in a Wheat Line Derived from Cultivated Einkorn (Triticum monococcum).

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive fungal diseases of wheat. Cultivated einkorn (Triticum monococcum L. ssp. monococcum, 2n = 2x = 14, AmAm), one of the founder crops of agriculture, harbors unexploited genetic sources for wheat improvement. An advanced wheat line, Z15-1949, with 42 chromosomes, selected from the hybrids of Pst-susceptible common wheat cultivar Crocus and resistant T. monococcum accession 10-1, exhibits high resistance to a mixture of the prevalent Chinese Pst races. Genetic analysis on F1, F2, and F2:3 generations of the cross between Z15-1949 and Pst-susceptible common wheat SY95-71 indicated that the resistance of Z15-1949 was conferred by a recessive gene, tentatively designated as YrZ15-1949. This gene was mapped to the short arm of chromosome 7D using the Wheat 55K single nucleotide polymorphism array, flanked by markers KASP-1949-2 and KASP-1949-10 within a 3.3-cM genetic interval corresponding to a 1.12-Mb physical region in the Chinese Spring reference genome V2.0. The gene differs from previously reported Yr genes on 7D based on their physical positions and is probably a novel gene. YrZ15-1949 would be a valuable resource for developing Pst-resistant wheat cultivars, and the linked markers could be used for marker-assisted selection.

Stem traits promote wheat climate-resilience.

Wheat grain filling processes under post-anthesis stress scenarios depend mainly on stem traits and remobilization of stem water-soluble carbohydrates (WSC). A diverse panel of advanced semi-dwarf spring wheat lines, representing a natural variation in stem traits (WSC content, stem diameter, peduncle length, and stem wall width), was used to identify specific traits that reliably reflect the relationship between WSC and grain yield. The panel was phenotyped under various environmental conditions: well-watered, water-limited, and heat stress in Mexico, and terminal-drought in Israel. Environmental stresses reduced grain yield (from 626 g m-2 under well-watered to 213 g m-2 under heat), lower internode diameter, and peduncle length. However, stem-WSC generally peaked 3-4 weeks after heading under all environmental conditions except heat (where it peaked earlier) and expressed the highest values under water-limited and terminal-drought environments. Increased investment in internode diameter and peduncle length was associated with a higher accumulation of stem WSC, which showed a positive association with yield and kernel weight. Across all environments, there were no apparent trade-offs between increased crop investment in internode diameter, peduncle length, and grain yield. Our results showed that selecting for genotypes with higher resource investment in stem structural biomass, WSC accumulation, and remobilization could be a valuable strategy to ameliorate grain size reduction under stress without compromising grain yield potential. Furthermore, easy-to-measure proxies for WSC (stem diameter at specific internodes and length of the last internode, i.e., the peduncle) could significantly increase throughput, potentially at the breeding scale.

Incidence of black point (Alternaria sp.) in elite advanced bread wheat (Triticum aestivum) lines

Eighty four elite advanced bread wheat lines were evaluated for resistance to black point during the crop season 2015-2016 at the Norman E. Borlaug Experimental Station in the Yaqui Valley, Mexico. Sowing dates were November 12, 19 and 26, 2015. Harvest and threshing were done manually in ten spikes per line, and the evaluation by visual inspection, counting healthy and infected grains to calculate the percentage of infection. The range of infection for the first sowing date was 0 to 19.8 %, with an average of 1.9; thirty nine lines did not show infected grains; for the second date it was 0 to 32.7 %, with an average of 4.8; twenty seven lines did not show infected grains; while for the third date, it was 0 to 44.9 % with an average of 6.8, and eighteen lines did not show infected grains. Eight lines did not show infected grains in the three dates. Lines with the highest average percentage of infection were: WHEAR/KUKUNA/3/C80.1/3* BATAVIA//2*WBLL1*2/4/WBLL1/KUKUNA//TACUPETOF2001/3/UP2338*2/VIVITSI with 20.8, and WAXWING*2/ KRONSTADF2004/3/TRCH/SRTU//KACHU/4/SAUAL/YANAC//SAUAL with 20.5%. Within the infection categories based on the average of the three dates, thirty lines were within the 0.1-2.5 % infection category, fourteen within 2.6-5.0 %, twenty three within 5.1-10.0 %, and nine lines within 10.1-30.0 %. The infection average of the group was 4.5 % with a range of 0 to 20.8 %, but some lines showed high percentage of infection in the dates, like WHEAR/KUKUNA/3/C80.1/3*BATAVIA//2*WBLL1*2/4/WBLL1/KUKUNA//TACUPETOF2001/3/UP2338*2/ VIVITSI, WAXWING*2/KRONSTADF2004/3/TRCH/SRTU//KACHU/4/SAUAL/YANAC//SAUAL, and BAV92//IRENA/ KAUZ/3/HUITES/4/DOLL/5/SERI.1B//KAUZ/HEVO/3/AMAD*2/4/KIRITATI with 44.9, 44.7, and 37.1 %, respectively, in the third date.

Comparison of Agro-Phenological and Technological Traits in Advanced Durum Wheat Lines Differing in Reaction to Hessian Fly Infestation

The aim of this study was to compare agro-phenological and technological traits in advanced durum wheat lines differing in responses to Hessian fly larval attacks. A field experiment was carried out during the 2014/2015 cropping season at the main research stations of Marchouch and Tassaoute in a randomized completed block design. Twenty-two durum wheat genotypes comprising twenty advanced lines from the INRA breeding program and two commercial varieties were used in this study. Agro-phenological and grain quality determinations were concerned with plant height, grain yield, days to heading, protein content, wet gluten content, gluten strength, and yellow pigment content. The analysis of variance revealed significant environment, genotype, and genotype-by-environment (G × E) effects for the majority of the measured traits. A high level of heritability was also observed for grain yield (94.9%), followed by gluten strength (90.7%), yellow pigment content (79.3%), wet gluten content (77.79%), plant height (71.5), and protein content (70.02%); moderate levels of heritability were recorded for days to heading (65.8%). The data for Hessian fly resistance in both the field and infested greenhouse demonstrated three distinct group of genotypes: “resistant” with 4 genotypes, “susceptible without field escape to Hessian fly attack” with 16 genotypes, and “susceptible with field escape to Hessian fly attack” with 2 genotypes. The ANOVA analysis indicated the existence of significant differences between groups of genotypes for grain yield, days to heading, protein content, yellow pigment content, and gluten strength at the Tassaoute station, while at the Marchouch site, the differences were significant only for plant height and gluten strength. Protein content and wet gluten content revealed highly significant positive correlations, indicating the possibility of effective selection of the two traits simultaneously. Biplot analysis indicated that the first two Principal Components (PCs) accounted for 56.04% and 56.34% of the relationships between the genotypes and all of the attributes at the Marchouch and Tassaoute sites, respectively. The results of principal component analysis and Cluster based on agro-phenological and grain quality traits categorized the genotypes into three separate groups for the Marchouch site and four groups for the Tassaoute site. Individuals within each group are characterized by well-defined precocity, productivity, and technological criteria. The different behaviors of the lines studied in the present work are of great interest and can be exploited in breeding programs in order to improve agro-phenological and technological traits in durum wheat.

Grain yield of wheat advanced lines adapted to stress, during the crop season 2017-2018

Twenty five advanced wheat lines which included six groups of sister lines and the commercial durum wheat cultivar Movas C2009 as well as bread wheat cultivar Borlaug 100 were sown on January 16 and 30, 2018, at the Norman E. Borlaug Experimental Station, in the Yaqui Valley, Sonora, Mexico. Plots consisted of 1 bed 2 m long with two rows and 0.80 m apart without replications, and a seed density of 100 kg ha-1. Average daily temperature (°C), maximum, minimum, relative humidity, rainfall, and cold units were recorded from January 16 to May 15, 2018. The variables evaluated were: days to heading, a thousand grain weight (g), and grain yield per plot (g). The average days for heading of lines was 69 days. The average plant height of the group was 84 cm; lines IWA8612949/3/2*ATILLA*2/PBW65//MURGA and BAV92/SERI showed a height of 100 and 95 cm, respectively. The average a thousand grain weight of the group was 41.3 g; line SOKOLL/3/PASTOR//HXL7573 /2*BAU/4/SOKOLL/WBLL1 showed the highest weight with 46.3 g, followed by IWA8612949/3/2*ATILLA*2 /PBW65//MURGA and CROC_1/AE.SQUARROSA(256)/4/PASTOR//HXL7573/2*BAU/3/WBLL1/5/BABAX/ LR42//BABAX/3/ER2000 with 46.2 and 45.3 g, respectively; while the line FRANCOLIN#1 showed the lowest TGW with 36.2 g. The average grain yield per plot was 339.5 g. Outstanding lines were W15.92/4/PASTOR// HXL7573/2*BAU/3/WBLL1 (442 g), SOKOLL (426 g), and FRANCOLIN#1 (422 g) which were above 5.27 t ha-1. The average temperature was 19.26°C with a maximum of 38.7°C and a minimum of 2.1°C; the average relative humidity was 64.0%; there were 9.1 mm of precipitation, and the number of cold units was 254.

Development of Short Duration, Tolerance to High Temperature and Bipolaris Leaf Blight, and Moderately Susceptible to Blast Disease of Wheat Genotype with Trials in Various Agroecological Zones in Bangladesh

Wheat production in Bangladesh faces to the detrimental effects of biotic and abiotic stresses that have been exacerbated by climate change. The development of short duration, high temperature and disease tolerant wheat variety is the most importance to produce higher yield combating the deleterious effects of the stresses. Some wheat lines (line was expressed by E) were evaluated at the different research stations of Bangladesh Wheat and Maize Research Institute (BWMRI) and farmers’ fields in consecutively three years under irrigated timely sowing (ITS) and irrigated late sowing (ILS) conditions. The days to heading (DH), days to maturity (DM), plant height (PH), spikelet spike-1 (SPS), grain spike-1 (GPS), thousand grain weight (TGW), and grain yield were depicted comparatively higher in ITS and ILS than ITS, but the severity of Bipolaris leaf blight (BpLB) and blast diseases were exhibited lower in BAW 1194 (E9) line than check varieties and other lines same conditions (BAW = Bangladesh Advanced Wheat). Those phenotypic and yield contributing characters, and BpLB and blast diseases were also observed lower in ILS than other genotypes. Further, E9 exhibited the lower percentage of yield loss in the ILS compared to ITS than check and other genotypes indicated its high temperature tolerance. In addition, E9 exhibited relatively higher grain yield than other genotypes in the candidate variety demonstration and multiplication yield trials. Therefore, BAW 1194 line may be released as a short duration, tolerance to high temperature and BpLB, and moderately tolerance to blast disease wheat variety to accelerate wheat production.