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Drought tolerance is a highly complex trait and one of the important components of yield stability in wheat. An experiment was therefore conducted to study the drought tolerance status of 14 high-yielding wheat varieties based on morphological characteristics under a randomized complete block design following factorial arrangement with three replications. Variety × Treatment × Year interactions of wheat genotypes were studied for various morphological traits under normal and drought stress conditions for 2 years in plants grown in pots. Significant differences were observed among the 14 varieties of wheat. Sutlej-86 was found to be highly affected by drought, with maximum reductions in plant height, spike length and number of spikelets/spike. The variety with the maximum tolerance to drought was Bahawalpur-97; this variety also had the lowest reductions in the number of fertile tillers/plant, the number of spikelets/spike, spike weight, the number of grains/spike, 1000-grain weight, grain yield/spike, total biomass and stress susceptibility and tolerance indices. Stronger correlations among the studied attributes under drought stress over normal conditions further highlighted drought stress adversities. The studied traits are thus recognized as drought tolerance indicators for varietal selection, and varieties showing less reduction under drought could be used as a standard check in breeding programmes to identify lineages with drought tolerance and could be recommended for drought-stressed areas.

Background. The length of the growing season is a limiting factor in many regions with unstable climatic conditions. The development of ultra-early barley donors makes it possible to accelerate the breeding process aimed at producing commercial cultivars adapted to cultivation area requirements.Materials and methods. The donors Kibel, Kibel uluchshenny, Kibtsel and Kibkor were obtained through individual selection of barley forms combining earliness and productivity from the hybrid combination Belogorsky × k-15881. The experiments were carried out according to the approved guidelines. Yield components were used to calculate the index of productivity for the donors versus the reference cv. ‘Belogorsky’.Results and conclusions. Earliness is controlled in the donors by three recessive genes. The donors’ period from emergence to heading was 7–9 days shorter than that of the reference cv. ‘Belogorsky’, with a low norm of reaction, which attested to their high adaptability. The resulting barley forms were highly resistant to lodging. The donor Kibel uluchshenny in all spike yield components did not differ from the reference. The other donors were close to the reference in spike length and 1000 seed weight. The example of Kibel uluchshenny was used to demonstrate the possibility of producing barley forms combining high earliness and good productivity. The developed donors may prove useful in the breeding for earliness in the areas where the length of the growing season is a limiting factor.

Herbarium collections have proven to be irreplaceable information base in recent studies directed towards revealing shifts in plants phenology and morphology caused by climate change. We examined eight parameters of morphological traits in the perennial herb species Plantago lanceolata L. collected in the wild between 1905 and 2019 and stored at the KW-herbarium (Kyiv, Ukraine) to find out if there were changes in plants’ organ sizes during the last 114 years. For this period, we also calculated 13 climatic parameters obtained from meteorological records from the State archive that gave us the opportunity to check if there are any relations between the climate change in Kyiv region and shifts in morphological parameters of plants. Our results have shown Plantago lanceolata leaf blades, petioles and spikes had become significantly longer with time, increasing 3.0 cm, 2.1 cm and 0.6 cm respectively. The Co-inertia analysis revealed that 34% of the morphological changes was attributed to climate change. The analysis also demonstrated that leaf length correlated more with raised temperatures when plants were in flower, while spike length depended on the temperatures during bud development. Received knowledge can be used to reveal rapid evolutionary processes of the Plantago species and predicting their further course for the construction of historical climate models based on the leaves traits.

The increasing economic importance of triticale (×Triticosecale Wittm.) makes this synthetic hybrid cereal an interesting object of genetic studies. Genomic regions (QTL) of morphological winter triticale traits were determined using the mapping population of 89 doubled haploids lines (DHs) developed from F1 hybrid of cv. ‘Hewo’ and cv. ‘Magnat’ accompanied with the genetic map consisting of 20 linkage groups assigned to the A (7), B (7), and R (6) genomes (total of 3539 DArT, SNP-DArT and SSR markers, length of 4997.4 cM). Five independent experiments were performed in the field and greenhouse controlled conditions. A total of 12 major QTLs located on 2B, 5A, 5R, and 6B chromosomes connected to the stem length, the plant height, the spike length, the number of the productive spikelets per spike, the number of grains per spike, and the thousand kernel weight were identified by a composite interval mapping (CIM).

Two consecutive cycles of selection were imposed on five F2 populations of bread wheat. The first cycle was a divergent selection for spike length conducted in favorable environment (optimal sowing date) and the response was measured under favorable and heat stress conditions of a late sowing date. Positive responses to selection for longer spikes were obtained under favorable (13.43%) heat stress (8.66%) conditions, whereas the responses for shorter spikes were 2.24 and 5.02% in the two environments, respectively. The realized heritability of spike length was greater under favorable conditions (0.25-0.56) than under heat stress (0.18- 0.41). Concurrent positive responses to selection for longer spikes were obtained in grain yield per spike under favorable (25.35%) and heat stress (13.65%) environments. Selection for greater number of grains per spike imposed on F3 plants selected for spike length under heat stress resulted in significant responses (14.65%). Selection for greater number of grains per spike resulted in correlated responses in grain yield per spike (17.64%). The concurrent positive responses produced in spike length in F4 with selection for number of grains per spike (averaged 9.20%) was almost equal to that produced by the direct selection in F3 (8.66%), indicating that selection advance effected in F3 has been maintained in F4. High F4/F3 regression was obtained for spike length under heat stress (b = 0.85 ± 0.07), indicating high heritability. In conclusion, phenotypic selection for longer spikes under heat stress followed by a cycle of selection for number of grains per spike was capable of improving heat tolerance in wheat.

Lilium and tuberose are promising geophytic flowers, which have high market demand in global floral markets. A study was conducted to optimize planting densities for cut lilium and tuberose production. Bulbs of Asiatic lily ‘Brunello’ and tuberose ‘Single’ were planted on 7.5 cm, 15.0 cm and 22.5 cm between bulbs while ridge were spaced at 60 cm apart. Lilium bulbs planted at 22.5 cm took 185 d, while tuberose took 101 d to produce flowers as compared to 7.5 cm spacing (173 d and 93 d, respectively). Bulbs of lilium and tuberose planted at 22.5 cm resulted in tallest plants with highest leaf area for both tested species, 69.1 cm and 11.4 cm2 for lilium and 110.6 cm and 30.2 cm2 for tuberose, respectively. Both species had highest number of florets with longer stem/ spike length and stem/spike diameter when planted 22.5 cm apart, while close planting further decrease number of buds/florets and stem/spike length. Similar results were recorded for fresh weight of a stem, while vase life and dry weight of a stem were relatively less affected by plant spacing. However, lilium and tuberose bulbs when planted at 22.5 cm plant spacing produced higher number of best quality stems for market as compared to other planting densities.

Simulating drought stress during the breeding process has been proposed as a way to select varieties under naturally non-stressful conditions. The aim of the study was to characterise the genetic basis of the response of 111 spring wheat (Triticum aestivum L.) varieties and landraces to chemical desiccation and to rain-out shelter drought. The effect of the rain-out shelter was a 15% reduction in plant height, spike length and thousand seed weight (TSW); in contrast, the desiccant treatment induced a 15% reduction in seed number, a 35-72% loss in TSW and a reduction in subsequent germination of 12%. A genome-wide association analysis revealed 263 significant marker-trait associations (MTAs), of which 246 involved days to anthesis, plant height, spike length, number of spikelets, seed number, TSW and germination from the non-treated plants. Only four and five MTAs involved TSW from plants grown under the rain-out shelter and the chemical desiccation, respectively, and harboured the Sugar-Dependent6 gene. Seven MTAs involved seed number for chemical desiccated plants. Both, chemical desiccation and rain-out shelter drought identified same tolerant genotypes. Concluding, both approaches are suitable to simulate different drought scenarios. However, there was a strong environmental impact for chemical desiccation which may increase the complexity of this tolerance mechanism.

Background: In breeding programs, the selection of cultivars with the highest yield potential consisted in the selection of the yield per se, which resulted in cultivars with higher grains per spike (GN) and occasionally increased grain weight (GW) (main numerical components of the yield). In this study, quantitative trait loci (QTL) for GW, GN and spike fertility traits related to GN determination were mapped using two doubled haploid (DH) populations (Baguette Premium 11 × BioINTA 2002 and Baguette 19 × BioINTA 2002). Results: In total 305 QTL were identified for 14 traits, out of which 12 QTL were identified in more than three environments and explained more than 10% of the phenotypic variation in at least one environment. Eight hotspot regions were detected on chromosomes 1A, 2B, 3A, 5A, 5B, 7A and 7B in which at least two major and stable QTL sheared confidence intervals. QTL on two of these regions (R5A.1 and R5A.2) have previously been described, but the other six regions are novel. Conclusions: Based on the pleiotropic analysis within a robust physiological model we conclude that two hotspot genomic regions (R5A.1 and R5A.2) together with the QGW.perg-6B are of high relevance to be used in marker assisted selection in order to improve the spike yield potential. All the QTL identified for the spike related traits are the first step to search for their candidate genes, which will allow their better manipulation in the future. EEA Marcos Juárez Fil: Pretini, Nicole. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires; Argentina Fil: Pretini, Nicole. Universidad Nacional del Noroeste de la Provincia de Buenos Aires (UNNOBA). Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires; Argentina. Fil: Vanzetti, Leonardo Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; Argentina Fil: Vanzetti, Leonardo Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Terrile, Ignacio Ismael. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Departamento de Trigo; Argentina Fil: Donaire, Guillermo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juarez; Argentina. Fil: González, Fernanda Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires; Argentina. Fil: González, Fernanda Gabriela. Universidad Nacional del Noroeste de la Provincia de Buenos Aires (UNNOBA). Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires; Argentina Fil: González, Fernanda Gabriela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino; Argentina.

Agronomic traits such as heading date (HD), plant height (PH), thousand grain weight (TGW), and spike length (SL) are important factors affecting wheat yield. In this study, we constructed a high-density genetic linkage map using the Wheat55K SNP Array to map quantitative trait loci (QTLs) for these traits in 207 recombinant inbred lines (RILs). A total of 37 QTLs were identified, including 9 QTLs for HD, 7 QTLs for PH, 12 QTLs for TGW, and 9 QTLs for SL, which explained 3.0–48.8% of the phenotypic variation. Kompetitive Allele Specific PCR (KASP) markers were developed based on sequencing data and used for validation of the stably detected QTLs on chromosomes 3A, 4B and 6A using 400 RILs. A QTL cluster on chromosome 4B for PH and TGW was delimited to a 0.8 Mb physical interval explaining 12.2–22.8% of the phenotypic variation. Gene annotations and analyses of SNP effects suggested that a gene encoding protein Photosynthesis Affected Mutant 68, which is essential for photosystem II assembly, is a candidate gene affecting PH and TGW. In addition, the QTL for HD on chromosome 3A was narrowed down to a 2.5 Mb interval, and a gene encoding an R3H domain-containing protein was speculated to be the causal gene influencing HD. The linked KASP markers developed in this study will be useful for marker-assisted selection in wheat breeding, and the candidate genes provide new insight into genetic study for those traits in wheat.

The spike traits of wheat can directly affect yield. F(2) and F(2:3) lines derived from the cross of the multi-spikelet female 10-A and the uni-spikelet male BE89 were used to detect QTLs for spike length (SL), total spikelet number per spike (TSS), kernel number per spike (KNS) and thousand-kernel weight (TKW) in four different environments. A total of 1098 SNP and 5 SSR were used to construct genetic map of 2398.1 cM with the average distance of 2.2 cM between markers. A total of 11 QTLs were identified for spike traits, including three QTLs for SL, five QTLs for TSS, two QTLs for KNS and one QTL for TKW. The QTLs mapped to chromosomes 2D, 4A, 6A, 7A and 7B explained 8.2–37.8% of the phenotypic variation in single environment. The major QTL confidence interval with distance of 0.5 cM was located on chromosome 4A and detected in multiple environments, which can explain more than 30% of the phenotypic variation for SL, TSS and KNS. Combining IWGSC RefSeq v1.0 and RNA-seq data for 10-A and BE89, we identified 16 genes expressed on spike or grain in four QTL regions. These findings provide insights into improving wheat yield through increasing spikletes in wheat, particularly through the use of the multi-spikelet female 10-A for breeding. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12298-020-00823-0) contains supplementary material, which is available to authorized users.

The objective of this study was to determine the cycle duration in days and the quantitative parameters, i.e. stem length, spike length and stem diameter of gladiolus floral stems as a function of the planting date and locations in the Rio Grande do Sul/Brazil. Field experiments were established between 2014-2015 in three locations (Frederico Westphalen, Itaqui and Santa Maria). The experimental design was a complete randomized block, with six gladiolus cultivars in three distinct planting dates at each location as treatments. The shift from vegetative to reproductive stage, the stem length, spike length and stem diameter were evaluated. Data was statistically analyzed by ANOVA and Tukey test. When planted during late July and early August, cultivars of early cycle (‘Purple Flora’, ‘Rose Friendship’ and ‘White Friendship’) and intermediate cycle (‘Green Star’ and ‘Jester’), produced floral stems of gladiolus in the desired patterns besides as well as having a shorter growth cycle than late cultivars (‘Gold Field’), being recommended for commercial cultivation in Southern Brazil. RESUMO O objetivo neste estudo foi determinar a duração do ciclo em dias e os parâmetros quantitativos de hastes florais de gladíolo em função da data de plantio e do local de cultivo no Rio Grande do Sul/Brasil. Experimentos de campo foram estabelecidos entre 2014-2015 em três locais (Frederico Westphalen, Itaqui e Santa Maria). O delineamento experimental foi o de blocos completamente casualizados, com seis cultivares de gladíolo em três diferentes datas de plantio em cada local como tratamento. Foram avaliadas a mudança do estágio vegetativo para o reprodutivo, o comprimento da haste, comprimento da espiga e diâmetro da haste no ponto de colheita. Os dados foram analisados estatisticamente pela ANOVA e pelo teste de Tukey. Quando plantadas durante o final de julho e início de agosto, cultivares de ciclo precoce (‘Purple Flora’, ‘Rose Friendship’ e ‘White Friendship’) e intermediário (‘Green Star’ e ‘Jester’) produzem hastes florais de gladíolo dentro dos padrões desejados, além de possuir um menor ciclo de crescimento do que cultivares tardias (‘Gold Field’), sendo recomendadas para cultivo comercial no Sul do Brasil.

A study was conducted to identify the best heterotic cross for various agromorphological and some quality traits involving 10 parents and their 45 F1s excluding reciprocals during 2012-13 and 2013-14. The higher magnitude of heterosis for all the agromorphological and quality traits was not expressed in a single cross combination. It varied from cross to cross due to diverse genetic background of their parents. The highest heterobeltiosis (35.68%, 11.11%, 11.44%), average heterosis (38.97%, 9.13%, 10.26%) and standard heterosis (31.09%, 7.84%, 10.41%) for grain yield, spikelets per spike and grains per spike respectively, was showed by HD 3095 x RAJ 4246 and this cross also showed highly significant (at

The objective of this work was to evaluate the effect of inoculation with Azospirillum brasilense, associated with N rates and sources, in soil of the Cerrado (Brazilian savanna), on the grain yield of irrigated wheat (Triticum aestivum). The experiment was carried out under a no-tillage system in a Typic Haplustox. The experimental design was randomized complete blocks with four replicates, in a 2x5x2 factorial arrangement: two N sources (urea and urea with NBPT urease inhibitor); five N rates applied as topdressing (0, 50, 100, 150, and 200 kg ha-1); and with or without seed inoculation with A.brasilense. The increase in the N rates positively affected spike length, number of spikelets and of grains per spike, number of spikes per meter, N accumulation in the straw, leaf chlorophyll content, and grain yield of irrigated wheat, regardless of the use of NBPT urease inhibitor with conventional urea. Singly, inoculation with A.brasilense does not affect production components and grain yield, despite the increase in N content in wheat straw. The inoculation with A.brasilense, associated with the application of 140 kg ha-1 N, provides the highest grain yield of irrigated wheat cropped after corn in low-altitude Cerrado. Resumo: O objetivo deste trabalho foi avaliar o efeito da inoculação com Azospirillum brasilense, associada a doses e fontes de N, em solo de Cerrado, sobre a produtividade de grãos de trigo (Triticum aestivum) irrigado. O experimento foi desenvolvido em sistema plantio direto, em Latossolo Vermelho distrófico. Utilizou-se o delineamento experimental de blocos ao acaso, com quatro repetições, em arranjo fatorial 2x5x2: duas fontes de N (ureia e ureia com inibidor da urease NBPT); cinco doses de N em cobertura (0, 50, 100, 150 e 200 kg ha-1); e com ou sem inoculação das sementes com A.brasilense. O aumento nas doses de N apresentou efeito positivo no comprimento de espiga, número de espiguetas e de grãos por espiga, número de espigas por metro, acúmulo de N na palha, conteúdo de clorofila na folha e produtividade de grãos de trigo irrigado, independentemente do uso de inibidor de urease NBPT com ureia. Isoladamente, a inoculação com A.brasilense não afeta os componentes de produção e a produtividade de grãos, apesar de incrementar o N na palhada de trigo. A inoculação com A.brasilense, associada à aplicação de 140 kg ha-1 de N, propicia as maiores produtividades de grãos de trigo irrigado, cultivado após milho em Cerrado de baixa altitude.

The temporal and spatial expression patterns of stable QTL for plant height and their influences on yield were characterized. Plant height (PH) is a complex trait in wheat (Triticum aestivum L.) that includes the spike length (SL) and the internode lengths from the first to the fifth internode, which are counted from the top and abbreviated as FIRITL, SECITL, THIITL, FOUITL, and FIFITL, respectively. This study identified eight putative additive quantitative trait loci (QTL) for PH. In addition, unconditional and conditional QTL mapping were used to analyze the temporal and spatial expression patterns of five stable QTL for PH. qPh-3A mainly regulated SL, FIRITL, and FIFITL to affect PH during the booting-heading stage (BS-HS); qPh-3D regulated all internode lengths to affect PH, especially during the BS-HS; before HS, qPh-4B mainly affected FIRITL, SECITL, THIITL, and FOUITL and qPh-5A.1 mainly affected SECITL, THIITL, and FOUITL to regulate PH; and qPh-6B mainly regulated FIRITL to affect the PH after the booting stage (BS). qPhdv-4B, a QTL for the response of PH to nitrogen stress, was stable and co-localized with qPh-4B. All five stable QTL, except for qPh-3A, were related to the 1000 kernel weight and yield per plant. Regions of qPh-3A, qPh-3D, qPh-4B, qPh-5A.1, and qPh-6B showed synteny to parts of rice chromosomes 1, 1, 3, 9, and 2, respectively. Based on comparative genomics analysis, Rht-B1b was cloned and mapped in the CI of qPh-4B. This report provides useful information for fine mapping of the stable QTL for PH and the genetic improvement of wheat plant type.

The field performance of 24 exotic cultivars of snapdragon (Antirrhinum majus L.) at three planting dates (November 10, 2009; March 10 and October 10, 2010) was assessed. Data of vegetative traits i.e., number of leaves, nodes, secondary shoots, plant height, fresh weight per plant and reproductive traits, including days to bud opening, spike length, and number of buds/spike, were recorded. Six cultivars (‘Potomac Early Rose’, ‘Maryland Lavender’, ‘Potomac Royal’, ‘Potomac White’, ‘Potomac Early Orange’ and ‘Monaco Violet’) showed superior vegetative growth while five cultivars (‘Potomac Early Pink’, ‘Maryland Golden Brnz’, ‘Monaco Yellow’, ‘Potomac Orange Dark’ and ‘Monaco Baltimore Rose’) performed poorly. ‘Potomac Early Rose’ and ‘Maryland Lavender’ performed best reproductively, and produced better quality flower spikes than all other cultivars. When considering the reproductive performance of these 24 snapdragon cultivars, sowing on November 10, 2009 was most suitable compared to the two other sowing dates. © 2016 Friends Science Publishers

The experiment was conducted at Jimma University College of Agricultures and Veterinary Medicine (JUCAVM) under field condition to determine the effects of different weeding time of Ryegrass on growth and yield components of Wheat (Triticum spp.) The experimental design used was randomized complete block design (RCBD) and each of the experimental treatment was replicated three times. A Wheat cultivar, Digalu was grown with Ryegrass and different weeding time of Ryegrass T1 (weeding 15-45 DAS), T2 (weeding 30-60 DAS), T3 (weeding 45-75 DAS), T4 (weed free) and T5 (no weeding) were used as a treatment. Data were recorded on Wheat Plant height, Stem thickness, Number of tillers; Spike length and Spike number. The result revealed that various weeding time of Ryegrass statistically (p≤0.05) affected Plant height, Stem thickness, Number of tillers; Spike length and Spike number. The maximum values of all the parameters were recorded in the (15-45 DAS) except for Plant height and Stem thickness. Whereas, the minimum values of these parameters were recorded from (45-75 DAS) except for Plant height. It is advisable for growers to remove the Ryegrass before the critical weed-crop competition period which is most probably (15-45 DAS) to keep the crop weed free at this period.

In the paper presented, 99 single seed descent barley lines as well as their parental forms Roland and Apex were studied. The grain weight components and their interrelations were analyzed using simple coefficients of correlation. The direct and indirect effects of such components on grain weight per plant and 1000-grain weight were estimated using path analysis. In the 2006 and 2007, the spike length and number of spikelets per spike were the determinants of grain weight. Genetic parameters as additive and epistasis effects were estimated for all studied traits. The results indicate the importance of both additive and epistasis gene effects of number of spikes per plant, grain weight per spike, grain number per plant and grain weight per plant in this study.

A field experiment was carried out at Siwa Oasis, Matrouh governorate, during 2012/2013 growing winter season, to study the response of wheat (Triticumaestivum, L.) cv. Sakha 94, to applications of humic acid rates (8.3, 10.7 and 13.1 kg/ha) and organic fertilizer rates (35, 47.5 and 60 m 3 /ha) under varying Siwa conditions. The most important results are summarized as follows:1) Variation in soil salinity had an impact on studied characters, especially those subjected to combined analysis over locations. 2) Spike length, no. of spikelet/spike and 1000-grain weight were increased with increasing both organic and humic acid rates in the three locations. 3) The data for combined analysis showed significant differences between locations, organic fertilizer rates and applied humic acid rates for plant height, no. of spikes/m 2 , no. of grains/spike, biological yield and harvest index. 4) Location 2, with lowest E.C. values gave significantly higher values for plant height, biological yield, grain yield and yield components, i.e. number of spikes/m 2 and number of grains/spike, and harvest index compared to location 1 and 3. 5) Increase in grain yield reached 7.1 and 13.6 % by increasing humic acid rate from 8.3 to 10.7, and from 8.3 to 13.1, respectively.

Screening experiment was performed on twelve genotypes of bread wheat (Ttriticum aestivum L.) to select the most stem rust resistant genotype (Misr1) and the most stem rust susceptible genotypes (Line 37 and Line 92) according to stem rust reaction. Crosses were carried out between the resistant parent (Misr1) with each of the susceptible parents as well as between the two susceptible parents (Line 37 and Line 92) to obtain the F1 kernels. Some of the F1 kernels were sown in the field and selfed to obtain the F2 kernels for each cross. These three selected parents, their F1 and the most resistant and susceptible F2 plant groups for the three crosses were evaluated for their response to stem rust resistance by recording some stem rust–related traits. However, infected condition caused a reduction in the values of all traits except spike length and number of spikelets per spike traits. The three parents, their F1 plants and some individual plants of the two contrasting F2 plant groups (the most resistant and the most susceptible F2 groups) for the three crosses were used to develop some molecular genetic markers associated with stem rust resistance using SSR and STS markers. The results indicated the presence of two positive markers out of the three SSR and three STS primers which used in this study. Sr2 (SSR) and Sr25 (STS) primers gave positive markers at fragment sizes of 120 and 130 bp, respectively, for stem rust resistance that could be considered as reliable markers for stem rust resistance in bread wheat (Ttriticum aestivum L.).

Rapid detection of allelic variation and identification of advantage haplotypes responsible for spike related traits play a crucial role in wheat yield improvement. The released genome sequence of hexaploid wheat (Chinese Spring) provides an extraordinary opportunity for rapid detection of natural variation and promotes breeding application. Here, selection signals detection and genome-wide association study (GWAS) were conducted for spike related traits. Based on the genotyping results by 90K SNP chip, 192 common wheat samples from southwest China were analyzed. One hundred and forty-six selective windows and one hundred and eighty-four significant SNPs (51 for spike length, 28 for kernels per spike, 39 for spikelet number, 30 for thousand kernel weight, and 36 for spike number per plant) were detected. Furthermore, tightly linkage and environmental stability window clusters and SNP clusters were also obtained. As a result, four SNP clusters associated with spike length were detected on chromosome 2A, 2B, 2D, and 6A. Two SNP clusters correlated to kernels per spike were detected on 2A and 2B. One pleiotropy SNP cluster correlated to spikelet number and kernels per spike was detected on 7B. According to the genome sequence, these SNP clusters and their overlapped/flanking QTLs which have been reported previously were integrated to a physical map. The candidate genes responsible for spike length, kernels per spike and spikelet number were predicted. Based on the genotypes of cultivars in south China, two advantage haplotypes associated with spike length and one advantage haplotype associated with kernels per spike/spikelet number were detected which have not been effectively transited into cultivars. According to these haplotypes, KASP markers were developed and diagnosed across landraces and cultivars which were selected from south and north China. Consequently, KASP assay, consistent with the GWAS results, provides reliable haplotypes for MAS in wheat yield improvement.

An experiment was conducted to evaluate the productivity of wheat under different levels of phosphorus and method of application at Department of Agronomy, Sindh Agriculture University, Tandojam. Experiment was laid out in a RCBD (factorial) with three replications. The treatments were four phosphorus levels (P1 = 0 Kg?ha–1 + Recommended Nitrogen, P2 = 30 Kg?ha–1 + Recommended Nitrogen, P3 = 60 Kg?ha–1 + Recommended Nitrogen and P4 = 90 Kg?ha–1 + Recommended Nitrogen) and two placement methods (A1 = Drilling method and A2 = Broadcast method). The statistical analysis of phosphorus levels and placement exhibited significant differences to the maturity days, plant height, tiller production, spike length, grains per spike, seed index, harvest index and grain yield ha–1. However, the interactions of P levels and placement in all crop characters were non-significant except the grain yield/ha–1. The results revealed that application of 90 kg P ha–1 prolonged 143 days for maturity, taller plants (100.16 cm), more tiller plant–1 (13.50), lengthy spikes (12.83 cm), more grains spike–1 (51.33), heavier seed index (48.16 g), better harvest index (50.82%) and satisfactory grain yield (4240.50 Kg?ha–1). The unit increase in grain yield was positively correlated with the increased values of observed crop parameters by extending the values of maturity r = 0.85, plant height r = 0.94, tillers plant r = 0.96, spike length r = 0.95, grains spik–1 r = 0.97, seed index r = 0.95 and harvest index r = 0.97. It was concluded that 90 kg P ha–1 was superior level of phosphorus if, applied with seed drilling for obtaining satisfactory grain yield of wheat crop.

In order to study the effect of salts stress on the growth and yield of wheat (cv. Inqalab), a pot experiment was conducted in the wire-house of the Department of Soil Science, Sindh Agriculture University Tando Jam. The soil was artificially salinized to a range of salinity levels i.e . EC 2.16, 4.0, 6.0, 8.0 and 10.0 dS·m-1 with different salts (MgCl2 + CaCl2 + Na2SO4). The salinized soil used for the experiment was sandy clay in texture, alkaline in reaction (pH > 7.0) and moderate in organic matter (0.95%) content. The results showed that with increasing salinity there was an increase in the ECe, Na+, Ca2+, Mg2+ and Cl- and decrease in the K+, SAR and ESP values of the soil Increasing salinity, progressively decreased plant height, spike length, number of spikelets spike-1 1000 grain weight and yield (straw and grain). Adverse effects of salts on plants were associated with the accumulation of less K+ and more Na+ and Cl- in their flag leaf sap, grains and straw. This resulted in lower K+:5Na+ ratio in flag leaf sap, grains and straw of wheat plants. These results indicated that the effects of salts stress were greater at 10 than at 8, 6 and 4 EC dS·m-1.

The present study was carried out during the year 2013-14 on the screening of the selected linseed genotypes for yield performance in Sindh, Pakistan. The experiment was laid out at the experimental fields of Oilseeds Section, Agriculture Research Institute, Tandojam in a three replicated randomized complete block design. Twelve linseed genotypes (L-53, C-W-2, Shikarpur 2, P-16-4, L-8, 11-106, Hala 3, L-17, Santane, Summit, L-10 and check llsi 90) were screened for their agronomic performance and correlations amongst yield and its contributing traits were calculated. The analysis of variance suggested significant (P < 0.05) variation among linseed genotypes for all the traits studied in this experiment. Most of the genotypes attained flowering and maturity earlier than the check variety; while P-16-4 surpassed Ilsi-90 for primary branches; and most of the remaining genotypes were at par with the commercial check for primary branches. Genotype L-10 surpassed the commercial check for capsules plant-1 and L-8 was at par with the commercial check; while none of the genotypes could surpass commercial check variety for seed index, but 11-106, Hala-3 and Summit also showed promising performance regarding the seed index. All the genotypes tested in this experiment such as L-53, C-W-2, Shikarpur 2, P-16-4, L-8, 11-106, Hala 3, L-17, Santane, Summit, L-10 surpassed the commercial check variety Ilsi-90 for seed yield plot-1. The correlation coefficient for yield and its contributing traits of linseed genotypes showed a positive and significant (P < 0.05) association for primary branches plant-1 vs seed yield plant-1 (r = 0.3334*), days to maturity vs spike length (r = 0.5384**), days to 75% flowering vs days to 90% maturity (r = 0.4073**), days to 75% flowering vs seed index (r = 0.4291**), days to 90% maturity vs seed index (r = 0.3973**) and seed index v/s seed yield plot-1 (r = 0.5160**). Negative and significant (P < 0.05) association was observed for primary branches plant-1 vs days to maturity (r = -0.368*), capsules plant-1 vs days to maturity (r = -0.3567*), days to 90% maturity vs seed yield plant-1 (r = -0.4156**) and days to 90% maturity vs seed yield plot-1 (r = -0.3423*). The new genotypes possess the potential to become future varieties for general cultivation in Sindh province.

Anther development progresses through 15 distinct developmental stages in wheat, and accurate determination of anther developmental stages is essential in anther and pollen studies. A detailed outline of the development of the wheat anther through its entire developmental program, including the 15 distinct morphological stages, is presented. In bread wheat (Triticum aestivum), anther developmental stages were correlated with five measurements, namely auricle distance, spike length, spikelet length, anther length and anther width. Spike length and auricle distance were shown to be suitable for rapid anther staging within cultivars. Anther length is an accurate measurement in determining anther stages and may be applicable for use between cultivars. Tapetal Programmed Cell Death (PCD) in wheat begins between late tetrad stage (stage 8) and the early young microspore stage (stage 9) of anther development. Tapetal PCD continues until the vacuolate pollen stage (stage 11), at which point the tapetum fully degrades. The timing of tapetal PCD initiation is slightly delayed compared to that in rice, but is two stages earlier than in the model dicot Arabidopsis. The MYB80 gene, which encodes a transcription factor regulating the timing of tapetal PCD, reaches its peak expression at the onset of tapetal PCD in wheat.

Forty nine genotypes of wheat were evaluated for 12 quantitative and one quality traits during 2010-11. The experiment was conducted in randomized complete block design with three replications at Crop Research Centre, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut. The mean, range, genotypic and phenotypic coefficient of variation, heritability in broad sense, genetic advance correlation and path analysis were analyzed. Plant height, number of productive tillers per plant, spike length, 1000-grain weight, biological yield per plant and harvest index were significant and positive correlated with grain yield per plant. The phenotypic and genotypic path coefficients exhibited high positive direct contribution of number of productive tillers per plant, plant height, harvest index and 1000-grain weight towards grain yield.The positive indirect effect of plant height on grain yield was registered via days to maturity, number of spikelets per spike, 1000-grain weight and biological yield per plant. Number of productive tillers per plant revealed contribution on grain yield via number of grains per spike, 1000 grain weight, biological yield per plant and harvest index revealing that indirect selection of these characters would be effective in improving grain yield per plant. Higher genotypic coefficient of variance along with high heritability and genetic advance for grain yield per plant, plant height, number of spikelets per spike, number of grains per spike and 1000-grain weight would also be of great use for indirect selection for improvement in yield per plant.

A field experiment was conducted during Rabi season 2016 at Bacha Khan Agriculture Research Farm (BARF), Bacha Khan University Charsadda, using wheat variety Pir Sabak 2013. The experiment was laid out in RCB design having two factors i.e. tillage practices (cultivator using 1 time, 3 times, and 5 times) and mulching (M0-control, M1-wheat straw, and M2-sugarcane bagasse,). Tillage practices were applied to the main plots while mulching to the sub plots having 3 replications with a net plot size of 1.8m x 5m (9m2) and row to row distance of 30 cm. Data were recorded for days to emergence, plant height, spike length, 1000-grain weight and grain yield. Results of the experiment showed that both tillage practice and mulching has significant effect on almost all the parameters. Tillage showed significant variation for all of the parameters recorded during the course of study except days to emergence. Maximum emergence (199 seedlings m-2), were attained by 1 time tillage application where maximum plant height (108 cm), maximum spike length (12 cm), maximum 1000-grain weight (45 g) and maximum grain yield (4717) were observed for 5 time tillage application. Similarly mulching application significantly affected all the parameters recorded during the course of experiment except days to emergence. Maximum plant height(110 cm), spike length (13 cm),1000-grain weight (44 g) and grain yield (5122 kg ha-1) were recorded for M1during the experiment. Overall, the combination of five times tillage and wheat mulching (M1) provide its superiority in term of yield i.e. 4717 kg ha-1 and 5122 kg ha-1, respectively. Keywords: Wheat; Tillage; Mulching; Growth; Yield http://dx.doi.org/10.19045/bspab.2017.60015

This study was carried out at the research fields of The University of Haripur, during 2014-15 to evaluate three high yielding genotypes on the basis of their morphological characters using randomized complete block (RCB) design in three replications. Data were documented on ten traits viz., days to maturity (days), plant height (cm), flag leaf area (cm), days to flowering initiation (days), stem girth (mm), number of tillers plant (#), spike length (cm), spikelet’s spike (#), seeds spike (#) and 1000-seed weight (g). Highly significant differences were detected among the tested wheat genotypes for all the studied traits. Data for days to maturity ranged from 166 to 171 days, for plant height 82.3 to 103.6 cm, for flag leaf area 67.8 to 88.2 cm, for days to flower initiation 104 to 114.7 days, for stem girth 4.8 to 5.2 mm, for number of tillers plant 12 to 15.6 tillers, for spike length 11.9 to 12.0 cm, for spikelets spike 19.4 to 22.3 spikelets, for seeds spike 50.3 to 58.2 seeds and for 1000-seed weight 38.2 to 53.8 g. Generally, high heritability was estimated for the studied traits which varied from 57 % to 99 %. Days to flower initiation exhibited highest heritability value, whereas, minimum heritability was recorded for number of tillers plant. Based on the results of the current study, genotype Pirsabak-08 could be recommended for general cultivation in the agro-climatic conditions of Haripur.

Hristov N., N. Mladenov, A. Kondic-Spika, A.Marijanovic Jernomela, B. Jockovic, and G. Jacimovic (2011): Effect of environmental and genetic factors on the correlation and stability of grain yield components in wheat - Genetika, Vol 43, No. 1, 141 -152. More effective breeding and development of new wheat genotypes depend on an intricate analysis of the complex relationships among many different traits. The objective of this paper was to determine the interrelationship, direct and indirect effects, and stability of different yield components in wheat. Forty divergent genotypes were analyzed in a three-year study (2005-2007). Highly significant correlations were found between grain yield per plant and all the other traits analyzed except spike length, with the only negative correlation being that with plant height. Path analysis revealed highly significant direct effects of grain number per spike, grain mass per spike and 1000 grain weight on grain yield per plant. Analysis of stability parameters showed that the stability of grain yield per plant depended for the most part on the stability of grain number per spike, grain mass per spike and harvest index. Cluster analysis identified genotypes with a high performance for grain yield per plant and good stability parameters, indicating the possibility of developing wheat varieties with a high potential and high stability for a particular trait.

The aim of this wok was to evaluate the agronomic performance of three-waycross maize hybrids grown in different environments, to determine linear associations and to employ multivariate analysis for the measured traits. The experimental design used was randomized blocks in factorial scheme, arranged in three replicates. The three-way cross maize hybrids evaluated evidence phenotypic variability for the traits spike diameter, spike length, number of rows with grains, number of grains per row, cob mass and spike grains mass. The growing environment of Campos Borges-RS favors the increment of spike diameter, number of grains per row, spike mass, cob diameter, cob mass, mass of a thousand grains, spike grains mass and grain yield. Significant interactions between three-way cross maize hybrids and growing environments are verified for plant height, spike insertion height and prolificity. The traits spike diameter, mass of a thousand grains and mass of grains per spike present positive correlation with maize grain yield. The distinction of three-way cross hybrids is based on spike insertion height, spike diameter, plant height and mass of a thousand grains. The hybrids 2B688 HX® and 2A55 HX® are genetically closer, according to the biometric approach of canonical variables.

The French INRA wheat (Triticum aestivum L. em Thell.) breeding program is based on multilocation trials to produce high-yielding, adapted lines for a wide range of environments. Differential genotypic responses to variable environment conditions limit the accuracy of yield estimations. Factor regression was used to partition the genotype-environment (GE) interaction into four biologically interpretable terms. Yield data were analyzed from 34 wheat genotypes grown in four environments using 12 auxiliary agronomic traits as genotypic and environmental covariates. Most of the GE interaction (91%) was explained by the combination of only three traits: 1,000-kernel weight, lodging susceptibility and spike length. These traits are easily measured in breeding programs, therefore factor regression model can provide a convenient and useful prediction method of yield.

Background The maize male inflorescence (tassel) produces pollen necessary for reproduction and commercial grain production of maize. The size of the tassel has been linked to factors affecting grain yield, so understanding the genetic control of tassel architecture is an important goal. Tassels are fragile and deform easily after removal from the plant, necessitating rapid measurement of any shape characteristics that cannot be retained during storage. Some morphological characteristics of tassels such as curvature and compactness are difficult to quantify using traditional methods, but can be quantified by image-based phenotyping tools. These constraints necessitate the development of an efficient method for capturing natural-state tassel morphology and complementary automated analytical methods that can quickly and reproducibly quantify traits of interest such as height, spread, and branch number. Results This paper presents the Tassel Image-based Phenotyping System (TIPS), which provides a platform for imaging tassels in the field immediately following removal from the plant. TIPS consists of custom methods that can quantify morphological traits from profile images of freshly harvested tassels acquired with a standard digital camera in a field-deployable light shelter. Correlations between manually measured traits (tassel weight, tassel length, spike length, and branch number) and image-based measurements ranged from 0.66 to 0.89. Additional tassel characteristics quantified by image analysis included some that cannot be quantified manually, such as curvature, compactness, fractal dimension, skeleton length, and perimeter. TIPS was used to measure tassel phenotypes of 3530 individual tassels from 749 diverse inbred lines that represent the diversity of tassel morphology found in modern breeding and academic research programs. Repeatability ranged from 0.85 to 0.92 for manually measured phenotypes, from 0.77 to 0.83 for the same traits measured by image-based methods, and from 0.49 to 0.81 for traits that can only be measured by image analysis. Conclusions TIPS allows morphological features of maize tassels to be quantified automatically, with minimal disturbance, at a scale that supports population-level studies. TIPS is expected to accelerate the discovery of associations between genetic loci and tassel morphology characteristics, and can be applied to maize breeding programs to increase productivity with lower resource commitment. Electronic supplementary material The online version of this article (doi:10.1186/s13007-017-0172-8) contains supplementary material, which is available to authorized users.