Promising Wheat Genotypes Research Articles

Proximal canopy sensing of twenty-two bread wheat genotypes for nutritional quality, yield attributes and grain yield under Mediterranean climate

To ensure nutritional security of rapidly increasing population, research interest has revitalized in determining the nutritional quality traits of staple food crops, especially wheat. Besides higher yield potential, research gaps exist regarding nutritional quality assessment of promising wheat genotypes grown under the Mediterranean climate. A field study was conducted to determine the relationship between yield components and quality characteristics of 22 bread wheat genotypes using the SPAD meter, GreenSeeker (NDVI), and CM-1000 chlorophyll meter at different growing stages (Stem elongation, Heading, Anthesis and Milk stage). The recorded findings revealed that G-41 genotype surpassed the rest of bread wheat genotypes by recording the maximum grain yield, whereas G-60 genotype exhibited the highest protein and wet gluten content. Among response variables, SPAD and NDVI values at the heading stage and CM-1000 values at the milk stage were found to be statistically insignificant. According to the correlation and biplot analysis, a significant positive correlation was found between the SPAD values measured for the stem elongation, anthesis and milk stage and yield and quality characteristics. Significant positive correlations were found between the NDVI values at the stem elongation, anthesis, and milk stages and the yield components, and between the CM-1000 value at the heading stage and the grain yield.

Genetic Variability of Yield and Some Agronomical Traits of Promising Wheat Genotypes by R Project “Metan Package”

Abstract Plant breeders have to employ strategies and techniques to produce new improved wheat cultivars to increase productivity to meet the needs of the growing population. Therefore, they have to develop a new cultivar for adaptation to a new environment and new management practices. One of the most important criteria plant breeders should focus on is the exploitation of genotype × environment interaction (GEI). Thus, this study aimed to assess the variability of 24 wheat genotypes growing in different seasons by using the R software “Metan Package”. Moreover, the study estimates the stability parameters and finally highlights the winning genotypes across seasons. Field experiments were conducted across three consecutive seasons specifically 2019/2020, 2020/2021 and 2021/2022 and at different locations. The assessment was done on traits such as plant height [cm], flag leaf area [cm2], chlorophyll index [SPAD], spike number [spike/m2], fertility ratio [%], grain number [grain/spike], grain weight [g], and yield [kg/ha]. Results indicated different performances of wheat genotypes in certain environments as well as across the three environments included in this study. Winner genotypes such as G-20, G-10, G-30, G-4, and IRAQ were selected according to their stability and high grain yield potential. It can be concluded that the use of the Multi-Environment Trail Analysis-METAN package is powerful for detecting promising wheat genotypes with high and stable yields across different environments and under various climate change conditions. Furthermore, it can be recommended that wheat performance needs to be assessed across very wide geographical locations.

Performance assessment of wheat genotypes based on the superiority index using additive main and multiplicative interaction effects and BLUP analysis

The simultaneous use of additive main and multiplicative interaction effects (AMMI) and best linear unbiased predictors (BLUP) has been reflected in the multi-location evaluation of trials for number of crops. The additional advantages of both these approaches would be combined in superiority index (SI) to have an edge over the commonly used approaches. The promising wheat genotypes had been considered under multi location trails in Peninsular zone of India during the cropping seasons of 2018-2019 and 2019-2020. The highly significant environmental effects contributed 44.1% & 35.3% of total sum of squares in the AMMI analysis, 20.6% & 26.2% were augmented by G × E interaction, while 10.8% & 7.5% were contributed by the genotypes.Wheat genotypes of UAS3001, MACS6222, GW322, and DDW48 expressed their superiority in BLUP values. Superiority indexes and adaptability measures had identified WHD964 and DDW48 genotypes for the second year of study. More than 75% variations among the considered measures were due to the first two interaction principal components (IPCA’s) under Biplot analysis. Number of superiority index measures were clustered with adaptability measures in the same quadrant. Superiority index, the weighted measure of yield and consistent performance of genotypes would be more appropriate for stability and adaptabilities studies.

Screening of bread wheat genotypes for heat tolerance using artificial and natural environment

Increasing temperature because of climate change is one of the leading constraints to wheat productivity by adversely affecting its growth and development. Global warming would push the wheat cultivation further into heat stressed environment in future which may ultimately cause yield loss. This research directed for determination of heat tolerance level among different wheat genotypes to establish selection criteria under high temperature to select promising wheat genotypes for breeding. Hundred wheat accessions including 97 lines from international Maize and wheat improvement centre’s (CIMMYT) heat nurseries and three local checks were assessed for tolerance against high temperature in glass house and open field. In glass house, at seedling stage data was recorded for fresh shoot weight, dry shoot weight, leaf relative water content and electrolyte leakage. In open field data for heat and yield related traits were recorded and subjected to mean square analysis. Studied traits were pooled through cluster analysis. Results showed that these traits have potential to discriminate heat tolerant and susceptible genotypes. Variances between genotypes were highly significant for all investigated traits under both circumstances. Accessions HTSBWON-15-0002, HTSBWON-15-0029, HTSBWON-15-0040, HTSBWON-15-0079, HTSBWON-15-0087, HTSBWON-15-0089 and Faisalabad-08 performed good for heat and yield related traits particularly electrolyte leakage and leaf relative water content. Hence, based on analysis it could be deduced that these genotypes may be used in hybridization programs for development of heat tolerant wheat genotypes with high yield potential.

Multiple Stresses of Wheat in the Detection of Traits and Genotypes of High-Performance and Stability for a Complex Interplay of Environment and Genotypes

The effect of traits and the interaction of genotype × environment (GE) is one of the major challenges in detecting traits and genotypes with outstanding performance and stability through various stresses and years. The objective of this study was to identify the genetic influence traits of wheat, and genotypes with outstanding performance and stability under different environmental stress. The trials were carried out in two consecutive seasons with three treatments (optimal irrigation, limited irrigation, and heat stress), totaling six test environments at two different locations. After observing the importance of GE interaction, and the statistical significance for all studied traits, multivariate analysis was applied using stepwise regression (SR) for detecting influenced traits, and AMMI, AMMI’s stability values (ASV), yield stability index (YSI), superiority and GGE biplot methods to identify the genotype’s phenotypic stability. SR analysis showed that nine out of 22 traits have contributed significantly to grain yield (GY), which varied according to the environment. Equations of the models (GY) regression coefficient values reflected the importance seven of them have on a significant positive correlation on GY. The study confirmed the importance of AMMI and GGE biplots in decoding the GEI based on GY data. AMMI1 biplots showed that the three environments E1, E4, and E6 were the stronger interacting environments than E2, E3, and E5, in which the interaction was weak. YSI, superiority analysis, and superiority multi-trait analysis scores were largely compatible. YSI scores described the six genotypes viz, G5 (DHL26), G12 (DHL29), G10 (DHL01), G18 (Sakha-93), G2 (DHL02) and, G6 (Gemmeiza-9), these were marked by high stability and productivity. The GGE biplot analysis showed genotypes (G15 (Misr1) and G4 (DHL07)) recorded the highest grain yield in E3 and E4, whereas genotype G18 (Sakha-93) was in E6. It also showed G19 (Pavone-76) was the best genotype due to being situated in the center of the concentric circles and due to its high-yield. The methods considered were compatible with the detection of promising wheat genotypes with high mean performance and outstanding phenotypic stability across various stresses and years.

Agro-morphological diversity in promising wheat genotypes grown under restricted irrigated condition

A set of 36 promising genotypes were evaluated for 33 agro-morphological traits. Sufficient genetic variability was found for almost all the characteristics of wheat. Genetic diversity among nineteen traits of wheat genotypes was estimated using Mahalanobis D2 analysis and principal component analysis (PCA). Sufficient genetic diversity was observed among the genotypes and grouped genotypes into five clusters by Tocher’s method. Cluster I contained the maximum numbers of genotypes (32) and the remaining clusters II, III, IV and V were mono-genotypic. The lowest inter cluster distance was noticed between clusters III and I (260.57) and maximum between Cluster IV and V (891.62). The larger inter-cluster distances between clusters were considered more diverged than those with small distances. The major contributing character towards genetic divergence was found to be grain yield per plant (25.24%), followed by wet gluten (21.59%), chlorophyll content (11.11%) and protein content (10.63%). Principal component (PC) analysis resulted in eight principal components (PCs) having Eigenvalue >1 which contributed 78.67 per cent of the total variability amongst the wheat genotypes assessed for various morpho-physiological traits. The traits with the highest weight in component first were the number of tillers per plant, the number of ear per plant, grain yield per plant and harvest index which explained 15.17 per cent of the total variation. Component 2 was associated with protein content and wet gluten content which account for 13.91 per cent variation. In component 3, traits with highest weight were days to heading, days to maturity, plant height, the number of spikelets per ear, ear length and relative water content which explained 13.41 per cent of the total variation. Similarly, the traits with the highest weight in component 4 were sedimentation value; biological yield per plant in component 5; ear weight and chlorophyll content in component 6; peduncle length, 1000-grain weight and canopy temperature in component 7 was the major contributing traits which account for 8.89, 7.78, 7.20 and 6.31 per cent variability, respectively for the above traits. The result of the present study could be exploited in the planning and execution of a future breeding programme in wheat. Key words: Principal component, genetic divergence, cluster analysis &nbsp

Impact of Irrigation on Yield Attributes of Seven Wheat Genotypes

Seven wheat genotypes i.e., PR-110, PR-112, PR-115, PR-118, PR-119, PR-120 and Pirsabak-13 were evaluated at: I0: Control, I1: irrigation at seedling stage, I2: irrigation at seedling and booting stages, I3: irrigation at seedling, tillering and booting stages and I4: irrigation at seedling, tillering, booting and grain formation stages. Among the genotypes, PR-115, PR-118 and PR-120 were found to be superior for grain yield and its related attributes under full and deficit water conditions. Irrigation at seedling + tillering + booting stages + grain formation stages (I4) produced statistically higher yield and related traits. It was also observed that in case of water shortage, irrigation at seedling and booting stages reduced the drastic losses in grain yield of wheat. The study suggested that identified promising wheat genotypes can be utilized in future breeding programs to develop drought tolerant varieties.
 Bangladesh J. Bot. 50(2): 235-243, 2021 (June)

Comprehensive Selection Criteria for High-Yielding Bread Wheat (Triticum aestivum L.) Hybrids under Salinity Stress

THE MOST important aspect of this investigation was evaluating a set of wheat genotypes with different responses to salt stress while conducting the selection process on the number of spikes/plant, the number of filled grains/spike, 1000-grain weight, and grain yield/plant traits besides, some physiological attributes and related to salinity tolerance such as Na+, K+ contents, Na+/K+ ratio, osmotic adjustment, proline, and glycine betaine contents under control and salinity conditions. The wheat genotypes were divided into two groups according to half diallel analysis. Where, the first one included parents, namely; Sakha 8, Shandweel 1, Masr 1, Giza 171, Sakha 94, Gimeaza 11, and Gimeaza 12, respectively. While the second group was 21 F1 wheat crosses obtained from half diallel crossing among the seven wheat genotypes. Heterosis over better-parent, general, and specific combining ability effects was the most important measurements for all studied traits for both experiments. Further, the seven wheat genotypes and the highest 5 F1 crosses were evaluated for the salinity tolerance indices test using grain yield/plant trait depending on all data estimated for all studied attributes under salt-stress treatment compared to the control experiment. The final results revealed that; parents 1, 2, and 3 besides, the crosses; P1 X P2, P1 X P3, P2 X P3, P2 X P4, and P3 X P4 exhibited a high trend in salinity tolerance under salinity stress treatment compared to the control experiment. Further, the previous wheat genotypes recorded high levels of salinity tolerance indices. SCoT markers determined the hybrids with the highest salinity tolerance indices. Out of nine primers used, only six generated polymorphic bands with 43 polymorphic bands. Therefore, identifying genetic evidence at the molecular level could be used in the future as a taxonomic tool to tolerate salinity in promising wheat genotypes.

Analytic Measures of Adaptability for Wheat Genotypes Evaluated under Restricted Irrigation Timely Sown Conditions for Central Zone of India

Background: Wheat improvement program of the country identify genotypes with specific and general adaptations to ensure sustain yield for food security of the people. Yield behavior of promising wheat genotypes were studied at twelve locations of Central Zone of the country under restricted irrigation timely sown conditions. Methods: Recent analytic measures of adaptability viz., Relative Performance of Genetic Values (PRVG), Harmonic Mean of Genetic Values (MHVG) and Harmonic Mean of the Relative Performance of Genotypes (MHPRVG) were compared by considering Best Linear Unbiased Predictors (BLUP) of genotypes based on mixed model approach. Result: Genotypes MP3288, BRW3775 and DBW110 had been marked by analytic measures PRVG, MHVG, MHPRVG, HM for high yield and better adaptability across locations as per first year (2016-17) findings. HI8791 and DBW110 genotypes occupied places near to the origin in Biplot graphical analysis. Specific adapta­tions of genotype HI8791 for Sagar and Dhanduka locations were observed. DBW110 would be suitable for Jabalpur, Gwalior and Udaipur locations, whereas BRW3775 identified for Kota, Sanosora and Vijapur. Genotypes GW495, GW322, HI8713 and GW1339 had achieved high yield and better adaptability during the year (2017-18). The genotype UAS466 had expressed specific adapta­tions to Jabalpur and Gwalior, whereas HI8627 for Bhopal and Udaipur, NIAW3170 were identified for Indore and Vijapur, DDW47 for Sansora, Dhanduka and Pratapgarh. The recent analytic measures based on harmonic means of the relative performance of predicted genetic values have been observed as an appropriate to identify the better adaptive genotypes with higher yield.

Morphological characterization and genetic analysis in bread wheat germplasm: A combined study of heritability, genetic variance, genetic divergence and association of characters

Abstract. The present study was conducted to assess the nature and magnitude of genetic variability and traits association of bread wheat genotypes for yield and related traits. A total of 180 genotypes were evaluated in alpha lattice design with three replications in 2017/18 cropping season. Data for 10 quantitative traits were collected and subjected to analysis of variance. The result from the analysis of variance revealed highly significant variability observed among genotypes for all traits studied. Phenotypic coefficient of variation (PCV) is superior over genotypic coefficient of variation (GCV) for most traits but narrow variations were found between PCV and GCV for most of the traits. Heritability in broad sense and genetic advance as percent of the mean (GA%) were relatively higher for Kernels per spike and grain filling period. Grain yield showed positive and highly significant (p≤0.01) association with number of tillers, kernel per spike and plant height both on genotypic and phenotypic levels.The path coefficient analysis showed that spike length, plant height and kernels per spike had positive direct effect on grain yield on both genotypic and phenotypic levels. Divergence analysis (D2) grouped the total test germplasm into 10 clusters. Among those, clusters IV and IX showed the highest genetic distance and thus the possibility to develop segregating populations upon the crossing of widely related genotypes in those clusters. The results could help researches to utilize the most promising wheat genotypes of this study in future breeding programmes for enhancing desirable traits.

Performance of Some Promising Rust Resistant Bread Wheat Genotypes Under Rain-fed Conditions

The current study was conducted to evaluate the performance and behavior of eight promising wheat genotypes produced by different breeding programs as comparing with the local wheat cultivars under rain-fed conditions at the experimental field of the College of Agricultural Engineering Sciences, University of Sulaimani in Bakrajo during two crop seasons 2014 to 2016. The experiments were laid out according to a randomized complete block design with three replications. Seeds were cultivated at a rate of 140 kg/ha in rows within plots. Host reactions of the tested genotypes with the pathogen population of Puccinia striiformis f. sp. tritici were also investigated under natural infection conditions at the same field. Results revealed high significant differences among the genotypes in term of all the studied traits. Charmo significantly surpassed all other genotypes in stem width (4.90mm), number of kernels per spike (58.41) and grain yield (3856.06 kg h-1), the higher value of grain weight (46.59g) was detected in Azmar 2, while the higher amount of spike per square meter (586.6 spike) was produced by the genotype Shaho2. Azmar2 significantly surpassed all other genotypes in spike length (12.7cm) and leaf area (48.51cm2) while the highest plant height (110.1cm) was detected in Maaroof. Based on the disease severity and coefficient of infection of the genotypes to yellow rust disease, Maaroof, Shaho and Azmar explored high disease resistance reaction and coefficient of infection, while SaberBeg, Aras and Adana showed high susceptibility to the disease.

Elicitation of salt stress-tolerant mutants in bread wheat (Triticum aestivum L.) by using gamma radiation

BackgroundGiven the strategic importance of wheat being the staple food for the vast majority of people, it was necessary to know reasons for the contraction and decline of its area globally and consequently its lower yield. Among the most important of these problems is the problem of a high level of salinity in both soil and irrigation water coming at the forefront of environmental challenges that hinder its production process at the local and global levels. Therefore, the genetic improvement of wheat for salinity tolerance was one of the most important priorities of this investigation.ResultsThe seven wheat accessions (Sakha 8 and its six M5 derived mutants) succeeded in drawing unique cases of salinity tolerance and were excellent especially mutants 1, 2, 3, and 5. The rest genotypes were coming in the second rank for this purpose and were very good in this regard. The promising wheat genotypes which recorded high salinity tolerance in the recent investigation exhibited also high genetic stability. This fact was proved after estimating some agro-morphological and physiological traits related to salinity tolerance based on evaluating some important genetic parameters besides salinity tolerance indices under stress experiment compared to the control treatment within two seasons. Data evaluated of expected genetic advance (GA) based on 5% selection proved that all values calculated during the two seasons under both treatments appeared low for all studied traits in this regard. However, it reflects the success of breeding for salinity tolerance in wheat using mutations but in relative terms. Molecular marker analysis profile using the six ISSR primers exhibited a total of 173 markers, 12 of them were monomorphic, while that 161 bands appeared polymorphic included 56 unique bands or positive markers and 7 negative markers with 93.06 % (polymorphism).ConclusionThe original wheat variety (Sakha 8) and its six M5 derived mutants exhibited high tolerance of salinity stress in all studied traits based on all genetic parameters and salinity tolerance indices calculated for both seasons under salinity treatment compared to the normal conditions. DNA fingerprinting analysis as well for the six wheat mutants besides the local variety proved that these genotypes were recorded highly genetic differences among them.

Effects of selective intermating in bread wheat (Triticum aestivum) for crop improvement

The effects of intermating in F2 generation on mean, genetic variability, heritability and genetic advance in two crosses of wheat (Triticum aestivum L.) (WH 542/WH 1080) and (WH 1105/RAJ 3765//WH 283) were studied. The mean and genetic advance of all the seven characters, viz. days to heading, plant height (cm), number of effective tillers, number of grains/ear, 1000 grain weight (g), biological yield/plant (g), grain yield/plant (g) were increased after first cycle of intermating. Second cycle of intermating further showed its positive impact on mean, genetic variability, heritability and genetic advance. In this study the intermated population produced progenies which out yielded the F2 population indicating the superiority of intermating over the F2 in generating superior performing progenies. The result indicated that the intermated populations are potential candidates for further selection to improve the grain yield in bread wheat and may prove highly useful in generating promising wheat genotypes having desirable quality traits and stress tolerance.

QTL Mapping of Diffuse Reflectance Indices of Leaves in Hexaploid Bread Wheat (Triticum aestivum L.)

Quantitative trait loci (QTL) mapping of diffuse reflectance indices of laminas in bread wheat (Triticum aestivum L.) has been first performed under controlled conditions of a regulated agroecobiological testing ground in the presence or absence of nitrogen fertilizers. Indices chosen for the study determine a range of important characteristics, such as the content of chlorophylls and anthocyanins, carotenoid/chlorophyll ratio, photochemical activity of the photosynthetic apparatus, light scattering on a lamina, assimilating leaf surface area, and grain productivity. In total, 31 QTLs have been mapped. A significant correlation has been revealed between the introduction of a nitrogen fertilizer and the five of six optical characteristics of the photosynthetic apparatus activity in bread wheat. The only exception is the reflectance index for near-infrared radiation (800 nm), which depends on the structural features of leaf tissues. No statistically significant correlation has been revealed between the thousand-grain weight and spectral characteristics of the diffuse reflectance of the lamina measured at the booting stage. However, a significant correlation between the number of grains formed in the spike of the main stalk and the traits characterizing activity of the photosynthetic apparatus (reflectance indices, leaf area) has been observed. Results of the performed variance, correlation, and QTL analyses confirm each other indicating reliability of the revealed effect of nitrogen nutrition level on the manifestation of the studied reflectance indices in bread wheat under strictly controlled conditions of an agroecobiological testing ground. Application of noninvasive optical methods provides a high-throughput assessment of photosynthetic intensity in plants and, therefore, can be used for efficient selection of promising wheat genotypes with high grain productivity under both controlled and field conditions.

Analysis of the Genetic Diversity and Population Structure of Austrian and Belgian Wheat Germplasm within a Regional Context Based on DArT Markers.

Analysis of crop genetic diversity and structure provides valuable information needed to broaden the narrow genetic base as well as to enhance the breeding and conservation strategies of crops. In this study, 95 Austrian and Belgian wheat cultivars maintained at the Centre for Genetic Resources (CGN) in the Netherlands were characterised using 1052 diversity array technology (DArT) markers to evaluate their genetic diversity, relationships and population structure. The rarefacted allelic richness recorded in the Austrian and Belgian breeding pools (A25 = 1.396 and 1.341, respectively) indicated that the Austrian germplasm contained a higher genetic diversity than the Belgian pool. The expected heterozygosity (HE) values of the Austrian and Belgian pools were 0.411 and 0.375, respectively. Moreover, the values of the polymorphic information content (PIC) of the Austrian and Belgian pools were 0.337 and 0.298, respectively. Neighbour-joining tree divided each of the Austrian and Belgian germplasm pools into two genetically distinct groups. The structure analyses of the Austrian and Belgian pools were in a complete concordance with their neighbour-joining trees. Furthermore, the 95 cultivars were compared to 618 wheat genotypes from nine European countries based on a total of 141 common DArT markers in order to place the Austrian and Belgian wheat germplasm in a wider European context. The rarefacted allelic richness (A10) varied from 1.224 (Denmark) to 1.397 (Austria). Cluster and principal coordinates (PCoA) analyses divided the wheat genotypes of the nine European countries into two main clusters. The first cluster comprised the Northern and Western European wheat genotypes, whereas the second included the Central European cultivars. The structure analysis of the 618 European wheat genotypes was in a complete concordance with the results of cluster and PCoA analyses. Interestingly, a highly significant difference was recorded between regions (26.53%). In conclusion, this is the first study to reveal the high diversity levels and structure of the uncharacterised Austrian and Belgian wheat germplasm maintained at the CGN as well as place them in a wider European context. The results should help plant breeders to utilise the most promising wheat genotypes of this study in future breeding programmes for enhancing wheat cultivars.

Response of the Most Promising Wheat Genotypes with Different Nitrogen Levels

Field experiments were conducted during winter seasons of 2013 and 2014 on the alkaline and silty loam soils of NWRP, Bhairahawa to study the interaction of the most promising wheat genotypes with different nitrogen levels under different agro-ecological zones and recommend the appropriate dose of nitrogen for newly released varieties. The experiment was laid out in split plot design: four nitrogen levels (0, 50, 100 and 150 kg/ha) as a whole plot and six wheat genotypes (BL 3623, BL 3629, BL 3872, NL 1008, NL 1055 and Vijay) as a sub-plot which were replicated three times. There was significant effect of varieties and nitrogen levels on plant height, number of spikes, thousand grain weight and grain yield in both the years. In first year, the highest grain yield of 3.35 t/ha was obtained from the application of nitrogen @ 150 kg/ha with the genotype BL 3872 which is followed by the genotypes BL 3623 (3.15 ton/ha) and NL 1055 (3.05 ton/ha). Similarly in second year, the genotype NL 1055 gave the highest grain yield of 4.01 ton/ha followed by genotypes BL 3629 (3.83 ton/ha) and BL 3623 (3.81 ton/ha) from the application of nitrogen @ 150 kg/ha. Based on two years results, it can be concluded that N was a limiting factor in the productivity of wheat. Nitrogen @ 150 kg per ha produced higher yield and yield attributing characters. Similarly, the wheat genotypes NL 1055, BL 3629, BL 3623 and BL 3872 were superior among the genotypes.

Evaluation of some promising wheat genotypes (Triticum aestivumL.) at different zinc regimes for crop production

Zinc is essentially required for crop growth and its insufficient supply to the plants may severely limit the yield traits of a crop. A field experiment was performed during rabi season of 2009–10 and 2010–11 to evaluate the performance of different wheat genotypes under different levels of zinc namely 0 kg ZnSO4 ha−1, 20 kg ZnSO4 ha−1 and 20 kg ZnSO4 ha−1 along with foliar spray of 0.5% solution of ZnSO4. Genotypes responded positively in terms of tiller number, grain and biological yield, spikelet length, spikelet number, grain number and thousandgrain weight. The best response was observed with the application of 20 kg ZnSO4 ha−1 along with foliar spray of 0.5% solution of ZnSO4. Zinc application brought about a maximum increase of 58.6% in tiller number, 63.7% in thousand-grain weight, 40.5% in biological yield, 66.1% in grain yield irrespective of genotypes and the year of study. Wheat genotypes exhibited a variation in their performance which has been exploited in this study. Genotypes UP-262, PBW-1...

Heritability Studies of Yield and Yield Associated Traits in Wheat Genotypes

This study was conducted to evaluate the performance of twenty three promising wheat genotypes and one indigenous cultivar over two years for yield and quality characteristics in order to assess the presence of variability for desired traits and a significant amount of variation for different parameters. Genetic parameters, correlations, and partial regressions were estimated for all the traits. Analysis of variance revealed significant differences among the genotypes for all the characters. The estimates of genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were high for grain yield per plant, plant height, biological yield and kernel weight and number of kernel per main spike. Broad sense heritability (H 2) estimates for various traits ranged from 50-100%. Grain yield per plant showed highly significant positive genetic and phenotypic correlation with kernel weight, number of kernels per main spike and number of spikelet’s per main spike. The total variability calculated through multiple correlation in the population for yield improvement accounted by fertile tiller number and kernel weight of main spike was 78.6% compared to 82.4% accounted by the all characters. It is concluded that more fertile tiller number and kernel weight of main spike are major yield contributing factors in selecting high yielding wheat cultivars.

Improvement of Knowledge and Skills Level of Wheat-Cultivating Farmers using On-Farm Researches

Abstract On-farm collaboration allows farmers and researchers to share observations, and lets the researcher draw on the farmer's experience with a farm and its problems. This can be a good beginning for choosing topics suitable for demonstrations or research ( Anderson and Lockeretz, 1991 ). The field study was conducted to evaluate yield comparison of seven bread and durum genotypes in two different locations (Helal-Ahmar and Astan-e-Ghods) of Khorasan Razavi, Iran. Analysis of combined data showed non-significant variation among two different locations. It means that ecological conditions of Helal-Ahmar and Astan-e-Ghods locations are offer for production of durum wheat. The bread wheat cultivar of G7 and durum wheat line G4 were both produced the highest grain yield in each farmers’ experimental fields. From the results, it can be concluded that the new selected promising wheat genotypes are able to increase the farmers’ level of economic and productivity.

Identification of promising wheat genotypes for crossing

The objective of this study was to identify promising wheat genotypes from the IAPAR breeding program for crosses by multivariate techniques. Measures of dissimilarity between genotypes were obtained from multicategoric variables. To identify clusters, Tocher optimization and UPGMA were used. The genotypes were divided into five diverging groups, indicating a wide genetic base of the wheat breeding program of the Agricultural Research Institute of Paraná (IAPAR). As indicated by the genetic distance, crosses involving the cultivars IPR 85 and IPR 118 seem to be the most promising to increase genetic gains in both grain and flour quality as well as for agronomic parameters.