Grain Yield Of Wheat Cultivars Research Articles

NITROGEN FERTILIZER APPLICATION TIME EFFECT ON THE SENESCENCE AND GRAIN YIELD OF DURUM WHEAT (TRITICUM DURUM DESF.)

The experiment progressed to evaluate the effects of time nitrogen fertilizer application on the senescence of durum wheat and its association with grain yield and its components. The experimental treatments, set up in a split-plot design, used five durum wheat cultivars (Adnham, Grecale, Duma, Sardar, Svevo) as the main plots, and the time nitrogen fertilizer application (100% tillering, 100% stem elongation, and 50% tillering + 50% stem elongation stages) under two locations in Northern Iraqi conditions. The results of this study indicated that late senescence cultivars (Grecale and Svevo) produced the highest flowering date (123.89 and 123.61 days), number of spikes/m2 (267.2 and 265.6 spikes), number of grains/10 spikes (330.5 and 323.6 grains), grain yield g/m2 (532.2 and 511.6 g), and harvest index% (38.72% and 39.86%). Moreover, the time of nitrogen fertilizer application at the tillering stage (early application) influenced most of the studied traits. Finally, extending photosynthesis capacity during the grain-filling phases by delaying the rate of senescence could be a better approach to improving the grain yield of wheat cultivars.

Evaluation of Phenological Stages, Changes in GDD, and Grain Yield in Wheat Cultivars in Response to Changes in Planting Date and Application of Paclobutrazol

Evaluation of Phenological Stages, Changes in GDD, and Grain Yield in Wheat Cultivars in Response to Changes in Planting Date and Application of Paclobutrazol

Assembly between wheat cultivars and soil microorganisms modulates phosphorus and water use efficiency

The current scientific evidence shows a synergistic role between phosphorus use efficiency (PUE) and water use efficiency (WUE). However, the interactions between plants and soil microorganisms that stimulate phosphorus (P) and water uptake could exhibit variation at the cultivar level. This manuscript aims to evaluate the influence of different wheat cultivars on soil microbial activities and functional diversity and how their interaction could affect plant performance in terms of PUE and WUE.Three wheat cultivars (Fritz, Chevignon, and Rancofén) differing in their ability to use P and water were grown under controlled conditions on an Andisol with background soil P-concentration of 4 mg P kg−1 (-P), which was enriched to 30 mg P kg−1 (+P). Water management was applied at two levels: well-watered (+W) and 30% of the water applied to + W (water stress, -W). Soil microbial activities were assayed at the anthesis stage, but wheat was harvested at the end of its phenological cycle.Phosphorus scarcity and water deficit stress negatively affected growth traits, P acquisition, and grain yield of wheat cultivars. The P concentration affected the acid phosphatase (APs) and dehydrogenase activity (DHA) more than water management.The community-level physiological profile (CLPP) was modulated by the cultivar, water management, and P concentration. The main drivers determining microorganisms' catabolic activity were water deficit stress and high P concentration in the soil. The P addition to plants facing water limitation increased by about 84% the CO2 production by soil microorganisms.Finally, the differences observed among cultivars and the soil microbial activities affected PUE and WUE performance, being Fritz the most efficient cultivar in both components in all conditions evaluated.Our data suggest that an assembly between cultivars and microorganisms affects the plant performance in terms of PUE and WUE.

The Course of Physiological Processes, Yielding, and Grain Quality of Hybrid and Population Wheat as Affected by Integrated and Conventional Cropping Systems

At present, under the conditions of climate change, for mainly environmental but also economic reasons, especially in the case of new wheat genotypes, alternative cropping systems are recommended in addition to the common conventional system. The aim of this study was to determine the effect of the integrated system (INTEG) and conventional system (CONV) on the physiological parameters, yield, and mineral composition of the grain, as well as the amount and quality of protein of winter wheat Hymalaya (hybrid cv.) and Formacja (population cv.) against the background of changing hydrothermal conditions in the years of the study. The field experiment was carried out in 2016–2019 in Przecław (50°11′00″ N, 21°29′00″ E), Poland. More favorable values of physiological parameters and grain yield were found in the CONV system than in the INTEG system. A more efficient course of the photosynthesis process in cv. Hymalaya effected a higher grain yield, which was similar in the INTEG system to that of cv. Formacja from the CONV system. The use of the CONV system effected an increase in the grain quality traits as well as the sum of gliadins and glutenins, including the subunits γ gliadins, LMW glutenins, and HMW glutenins. Grain of cv. Hymalaya from the INTEG system had higher contents of Fe, Mn, and Mg and more favorable composition of glutenin proteins and their HMW/LMW ratio than cv. Formacja. Higher values of quality traits and gluten protein fractions and subunits, along with a reduction in the grain yield of wheat cultivars, were favored by periods with rainfall deficit in the wheat ripening period, where low hydrothermal coefficients were recorded.

A synergistic increase in water and nitrogen use efficiencies in winter wheat cultivars released between the 1940s and the 2010s for cultivation in the drylands of the shaanxi Province in China

Although soil water and nutrients are two of the most important factors affecting growth and production of winter wheat, genetic improvement for wheat responses to water and nitrogen (N) levels has been rarely studied. In this paper, five dryland winter wheat cultivars representative of widely cultivated varieties released from the 1940s to the 2010s in Shaanxi Province, China, were grown in an open rainout shelter (which could be closed when rain threatened) under four contrasting water/N treatment combinations. Yield-related parameters, biomass accumulation, crop water productivity (WUE), and nitrogen use efficiency (NUE) were determined. The results indicated that water deficit and low N treatment caused a significant reduction in grain yield and flag leaf photosynthesis in the five wheat cultivars studied. However, NUE, grain protein content, and partial factor nitrogen productivity were significantly improved by N application under water deficit. Our results confirm the genetic improvement for plant growth, N accumulation, and grain yield in wheat cultivars released from the 1940s to the 2010s; newergenotypes showed the highest NUE under water deficit combined with N limited conditions. Additionally, based on principal component analysis, we found that the newer genotypes, i.e. those from the 2000s and the 2010s, are more sensitive to low nitrogen and water stress compared with the older genotypes from the 1980s, which are more sensitive to the combined effect of water and N limitations. Our findings provide a theoretical support for further improvement of the wheat yield potential, selection, and breeding of high-efficiency varieties in arid and semi-arid areas.

Timing and growing conditions of nitrogen topdressing influence the grain yield and protein content of four wheat cultivars

ABSTRACT The application of an adequate rate and splitting of nitrogen is essential for wheat grain yield and protein content. The aim of this work was to adjust nitrogen management approaches regarding agronomic performance and protein content of wheat cultivars in various environments. Field experiments were conducted under no-tillage system on soybean mulch during the 2011 and 2012 growing seasons in Londrina and Pato Branco regions. The experimental design was a randomized block in split plot with four replicates. Four wheat cultivars (IPR Catuara TM, BRS Gaivota, Quartzo, CD 120) were tested with six nitrogen (N) management forms. Were evaluated: number of ears per unit area (NEA); plant height (PH); thousand-kernel weight (TKW); test weight (TW); grain yield (GY); and protein content (PC). The combined ANOVA (p ? 0.01) and Tukey’s test (p ? 0.01) were used. The interaction between cultivars and environments influence all yield components, GY and PC. The interaction management forms of N and environments affected the TKW, NEA, GY and PC. The results showed that in low-rainfall environments, nitrogen topdressing could be suppressed with no negative effects on GY or PC. Under ideal weather conditions, the GY of wheat cultivars was enhanced on application of 60 kg.ha–1 N of urea at the beginning of tillering as well 20 kg.ha–1 of N at booting. Matching the appropriate cultivars to the ideal growth environment is essential for achieving high GY values. The nitrogen forms on the topdressing do not influence the PC of cultivars in Pato Branco.

Early Season Drought Largely Reduces Grain Yield in Wheat Cultivars with Smaller Root Systems.

In the Australian grainbelt, early winter rainfall has declined during the last 30 years, and farmers sow their crops dry, increasing the risk of early season drought. This study aimed to examine whether differences in the root systems were associated with tolerance to early season drought. Three wheat cultivars with different root systems were grown in 1 m columns in a glasshouse. Immediately after sowing in dry soil, 440 mL water (equivalent to 25 mm rainfall) was supplied to each column, and no water was added to induce the early-season drought for the next 30 days. Shoot and root traits were measured at the end of the early season drought, anthesis and at maturity, respectively. The restricted water supply reduced Ψleaf, stomatal conductance, leaf photosynthetic rate, shoot and root biomass. Early season drought delayed phenology in all cultivars, but there was recovery of root and shoot biomass at anthesis in all three cultivars. Leaf area and shoot biomass at anthesis in Bahatans-87 (large root system) recovered better than Tincurrin (small root system). At maturity, early season drought reduced grain yield more in Tincurrin than Bahatans-87. The slow phenology of Bahatans-87 allowed greater recovery after the drought in leaf area and shoot biomass, which may explain the smaller reduction in grain yield after early season drought.

GROWTH AND YIELD OF WHEAT IN RESPONSE TO SEED VIGOR AND SOWING DENSITIES

ABSTRACT In wheat crops, it is often observed that the number of plants per area is lower than that of viable seeds used, which may be related to both environmental conditions and seed vigor. The aim of this study was to assess the effect of seed vigor level at different sowing densities on growth, development, and grain yield in wheat cultivars. The experiments were conducted in Londrina and Ponta Grossa, PR, Brazil, under a randomized block design in a 2 × 2 × 3 factorial scheme, with four replications. Two seed vigor levels (high and low), two sowing densities (200 and 400 viable seeds per m2), and three wheat cultivars (BRS Sabiá, BRS Gaivota, and BRS Gralha Azul) were assessed. In order to assess growth and development, plant samples were collected at the phenological stages of seedling growth, stem elongation, booting, and ear emergence. We assessed the emergence of seedlings, height and dry matter of plant shoot, and grain yield. The sowing density of 200 seeds per m2 led to a higher shoot dry matter production per plant at the stages booting and ear emergence. The cultivar BRS Sabiá presented the highest grain yield in Londrina, while BRS Sabiá and BRS Gralha Azul presented the highest grain yield in Ponta Grossa. High vigor seeds favor stand establishment, growth and development of plants at early phenological stages, and grain yield of wheat.

Modelling the Grain Yield of Wheat in Irrigated Saline Environment with Foliar Potassium Fertilization

In the present study, an effort was made to calibrate and validate a crop model using the experiment generated data pertaining to growth and yield of wheat cultivars under irrigated saline environment using foliar potassium application. A field experiment was conducted at Water Technology Centre research farm, Indian Agricultural Research Institute, New Delhi, in split–split plot design during rabi 2011–2012 and 2012–2013 to generate data for simulation of FAO AquaCrop model. Two wheat cultivars (i.e. one salt tolerant KRL-1-4 and other salt susceptible HD 2894) under four salinity levels, viz, GW (1.7 dS m−1), 4, 8 and 12 dS m−1 were experimented under foliar and non-foliar treatments. AquaCrop model was calibrated using experiment data of rabi 2011–2012 and validated with data of rabi 2012–2013. The model evaluation parameters, viz, model efficiency (ME), index of agreement (d) and R2 pertaining to grain yield of both wheat cultivars predicted by validated model were averaged to be 0.86, 0.95 and 0.96, respectively, under all treatment levels. Moreover, the simulated biomass yield of both the cultivars was with average values of ME, d and R2 as 0.91, 0.97, and 0.93, respectively. However, model validation results for water productivity were 0.60, 0.82 and 0.93 for ME, d and R2, respectively. It was observed that the AquaCrop model simulation for grain yield was better as compared to biomass and water productivity for all treatment levels. Validated model resulted in predicted grain yield of both wheat cultivars with low prediction error (i.e. 1.77–6.52%) up to 8 dS m−1, whereas at 12 dS m−1 salinity level, the prediction error increased and varied from 21.7 to 37.5%. Nonetheless, the FAO AquaCrop model can be used with acceptable accuracy for simulation of grain yield of wheat cultivars using saline irrigation up to 8 dS m−1 with foliar potassium fertilization.

Studies on the relationship between crop traits and grain yield of wheat cultivars in south Kerman region, Iran

In order to determine the relationship between grain yield and some physiological and morphological traits in bread wheat cultivars in south Kerman region and to determine the contribution of those traits that have the greatest effect on grain yield as well as direct study of grain yield with its components, a study was conducted on four wheat cultivars with the highest wheat cultivars in the region and each cultivar of 10 fields was planted in 2016–17. The results of correlation showed that in all fields of the cultivars grain yield was positively and significantly correlated with plant height, awn length, spike length, number of seeds per spike, spike weight, number of stems per square metre, straw yield and biological yield. The highest positive correlation coefficient was related to the biological yield trait (0.88). In stepwise regression, the first variable was introduced into the model and alone (53.9%) explained the higher percentage of grain yield changes. The results of this study indicated that characteristics such as number of stems per square metre, number of seeds per spike, spike weight, 1000-grain weight and stem height as criteria for selection for improving grain yield in wheat were introduced.

Effect of Three Growth Regulators on Grain Yield of Wheat Cultivars under Different Moisture Regimes

Effect of Three Growth Regulators on Grain Yield of Wheat Cultivars under Different Moisture Regimes

Effects of blast on components of wheat physiology and grain yield as influenced by fungicide treatment and host resistance

Two field experiments (Exp. 1 and Exp. 2) were carried out to assess the physiological performance and grain yield of wheat cultivars BR‐18 (moderately resistant) and Guamirim (susceptible) inoculated with Pyricularia oryzae in plots treated or untreated with Ópera (fungicide 13.3% epoxiconazole + 5% pyraclostrobin). Results from regression analyses indicated that spike and leaf blast severity at 10–14 days after inoculation (dai) were associated with greater yield losses (highest negative slope) than severity at 18–22 dai. Relative to untreated Guamirim, there were 0.3% and 16% increases in Exp. 1 and 2, respectively, for untreated BR‐18 (resistance alone). For fungicide treatment alone, the mean yield of Guamirim increased by 20% and 61% in Exp. 1 and 2, respectively, relative to the untreated fungicide control, whereas for the fungicide treated BR‐18, the mean yield increased by 26% and 83% in Exp. 1 and 2, respectively. Fungicide application and cultivar resistance resulted in higher measures of leaf health and photosynthetic performance in both spikes and leaves than in the untreated susceptible reference treatment. The results from this study may be useful in future efforts to develop crop loss models and management guidelines for wheat blast.

Relationships between δ13C, δ18O and grain yield in bread wheat genotypes under favourable irrigated and rain-fed conditions

In previous investigations, carbon isotope composition (δ13C) has been used in C3 cereals to screen for genotypes with high transpiration efficiency and oxygen isotope composition (δ18O) has been shown to correlate with transpiration rate. We examined associations of δ13C of the grain and flag leaf and δ18O of the flag leaf with respect to grain yield in wheat cultivars in UK field conditions. Field experiments were carried out at University of Nottingham in 2009–10 and 2010–11 testing 17 wheat cultivars under fully irrigated and rain-fed conditions. Averaging across years grain yield was reduced by 1.69tha−1 (16.5%) in the rain-fed treatment (P<0.001). There was a negative linear relationship between grain yield and grain δ13C amongst cultivars, under both irrigated (R2=0.47, P<0.01) and rain-fed (R2=0.70, P<0.001) conditions. Grain δ13C was negatively correlated with flag-leaf stomatal conductance (r=−0.94, P<0.01) in a subset of six of the cultivars, indicating that higher transpiration efficiency was associated with lower stomatal conductance. The associations between grain yield and flag-leaf δ13C and flag-leaf δ18O amongst cultivars under irrigated and rain-fed conditions were not statistically significant. There was a positive linear relationship between flag-leaf δ18O and grain δ13C amongst cultivars under irrigated conditions (R2=0.38, P<0.01), indicating a trade-off between transpiration and transpiration efficiency (TE). Genetic variation in grain yield under rain-fed conditions was also associated with delayed onset of flag-leaf senescence (R2=0.35, P<0.05). The 17 wheat cultivars ranged in year of release (YoR) from 1964 to 2009 and grain yield increased linearly under irrigated conditions by 60.4kgha−1yr−1 (0.72%yr−1) and under rain-fed conditions by 47.5kgha−1yr−1 (0.66% yr−1) over the 45year period and grain δ13C composition decreased by 0.0255 and 0.0304‰ yr−1, respectively, indicating genetic gains in wheat yield potential in the UK seem likely to have been achieved through a lower TE, higher water uptake and lesser limitation of stomatal conductance.

ÍNDICE DE VEGETAÇÃO POR DIFERENÇA NORMALIZADA E PRODUTIVIDADE DE CULTIVARES DE TRIGO SUBMETIDAS A DOSES DE NITROGÊNIO

RESUMO O manejo da adubação nitrogenada na cultura do trigo tem se evidenciado fator limitante à produtividade da cultura na Região Sul do Brasil, e a utilização de novas técnicas como o índice de vegetação por diferença normalizada (NDVI) pode auxiliar na estimativa do potencial produtivo da cultura e, consequentemente, na determinação da adubação nitrogenada. O objetivo deste trabalho foi avaliar o uso do NDVI, obtido por sensores passivo e ativo, como ferramenta para estimar a produtividade de grãos de cultivares de trigo submetidas a doses de nitrogênio. O experimento foi conduzido em Guarapuava, PR, em blocos ao acaso, seguindo o esquema fatorial 4 × 5, com quatro cultivares e cinco doses de N. As avaliações realizadas compreenderam leituras de NDVI, matéria seca (MS) de parte aérea, nos estádios fenológicos de afilhamento, emborrachamento e florescimento, teor foliar de N e produtividade de grãos. Nas leituras de NDVI, constataram-se diferenças significativas entre cultivares em todos os estádios fenológicos e doses, assim como entre as doses e os estádios fenológicos, para ambos os sensores. Verificaram-se efeito da MS e do teor foliar de N nas leituras de NDVI, sendo possível gerar modelos para a estimativa desses atributos com base no NDVI e, ainda, estimar a produtividade no início de desenvolvimento da cultura.

ESTIMATION OF WHEAT STRAW AND RAPESEED USEFULNESS FOR WHEAT FERTILISATION IN ARABLE FARMING

The aim of the research was the estimation of wheat and rapeseed straw usefulness for fertilising plants in arable farming. The subject matter of the study was the analysis of the influence of soil fertilisation with wheat and rapeseed straw on the yield and changes in the content of phosphorus, potassium, calcium and magnesium in winter wheat grain cultivars: Finezja and Ludwig. The static field experiment was conducted at Agricultural Experiment Station, Grabow, Institute of Soil Science and Plant Cultivation – State Research Institute (51°21′ N, 21°40′ E) in the years 2008–2010 on Haplic Luvisol. The effect of fertilisation with wheat and rapeseed straw did not have a significant effect on grain yield of winter wheat cultivars ‘Finezja’ and ‘Ludwig’. The introduction of complementary nitrogen fertilisation caused an increase in grain yield of wheat cultivar Ludwig. Organic fertilisation with wheat and rapeseed straw as well as complementary nitrogen fertilisation did not significantly differentiate the content of phosphorus, potassium, calcium and magnesium in winter wheat grain cultivars ‘Finezja’ and ‘Ludwig’.

Genetic Improvement of Root Growth and Its Relationship with Grain Yield of Wheat Cultivars in the Middle-Lower Yangtze River

Genetic Improvement of Root Growth and Its Relationship with Grain Yield of Wheat Cultivars in the Middle-Lower Yangtze River

Competition of nine wheat (Triticum aestivum) cultivars against Melilotus alba

Ranking of crop cultivars competitiveness against the weeds could be an effective strategy in weed management that resulted in increased our knowledge about the crop ability to suppression of weeds. A field experiment was conducted at Qrakhyl Agronomy Research Station, Iran, to evaluate 9 wheat cultivars competitiveness against Melitotus alba. Wheat cultivars including Morvarid, Darya, Nai 60, Milan, N-85-5, N-87-4, N-86-7, N-80-19 and Shanghai planted in both presence and absence of M. alba in split plot design with four replicates. Competition reduced height, tiller number, grain and biological yield of cultivars. Wheat cultivars showed variations in response to competition. Morvarid cultivar was more successful in reducing M. alba biomass. A significant correlation was found between wheat height and weed biomass. Morvarid and Nai60 had the maximum competition index that representing higher ability of the cultivars to inhibit M. alba than other ones. Grain yield of wheat cultivars positively correlated with the ability to withstand competition (AWC). The wheat cultivars revealed variations in tolerance to competition.

Influence of Rhizobacteria Inoculation and Lead Stress on the Physiological and Biochemical Attributes of Wheat Genotypes

Abstract Contamination of soils by lead (Pb) is of widespread occurrence as result of human, agricultural and industrial activities. A pot study was carried out to evaluate physio-biochemical responses (chlorophyll content, soluble protein, proline content and activities of enzymatic antioxidants) of 10 bread wheat genotypes to inoculation of plant growth promoting rhizobacteria (combination of Azospirillum brasilense and Azotobacter chroococcum) under Pb stress (0 and 65 mg kg-1). Result revealed that lead stress averagely decreased grain yield of wheat cultivars by 41.4 %. Lead stress increased lipid peroxidation and induced a significant accumulation of proline in leaves. Protein content decreased from 8-25.4% in different cultivars in Pbcontaminated soils. Activities of antioxidant enzymes, such as, ascorbate peroxidase, superoxide dismutase and catalase were significantly increased in the presence of lead. An increase in total hydrogen peroxide (H2O2) content was noticed under lead stress in all cultivars, which was similar to production of malondialdehyde (MDA). However, promotion of growth was evident in most cultivars as a consequence of rhizobacterial inoculation, since plant growth promoting rhizobacteria could improve grain yield, proline content and membrane integrity, while significantly reduced the production of MDA and H2O2. Total chlorophyll content considerably declined with Pb stress. Between cultivars the best performance under lead stress was observed in Sardari, Shahriyar and Gaspard which had the highest yield and antioxidants activity. Obtained results showed that inoculation with Azotobacter and Azospirillium possibly through bioremediation strategy can stimulate plant growth under adverse environmental conditions, such as heavy metal contamination.

Response of Different Bread Wheat (Triticum aestivum L.) Genotypes to Post-Anthesis Water Deficit

Resources of water are limited in many agricultural areas of West Asia. Therefore, effective use of this scarce resource is very important in this region. So, this research was conducted in 2009-2010 growing season at Research Farm of Agricultural Researches Center of Khuzestan, Iran, to investigate the effects of two irrigation regime (I 1 : normal irrigation and I 2 : no irrigation in post-anthesis growth stage) on grain yield of five wheat cultivars (‘Chamran’, ‘S-78-11’, ‘A’and ‘S-82-10’). A split plot experiment based on randomized complete block design in three replications was used, with the irrigation regime in main plots and wheat cultivars in subplots. The results showed that 1000-grain weight, grains per spikelet and grain yield were decreased by water limitation. Despite of their significant differences (P<0.05) in 1000-grain weight, spikelets per spike and grains per spike, the grain yield of wheat cultivars was not significantly different. It was resulted by different grain yield reduction of genotypes under different irrigation regimes. Genotypes ‘S-80-18’ and ‘S-7811’ produced highest yield under normal irrigation and drought stress conditions, respectively. The yield reduction of ‘S-80-18’ genotype was highest under drought stress conditions. ‘S-78-11’ was the most tolerant genotype to water deficit occurrence.

Contribution of Stem Dry Matter to Grain Yield in Wheat Cultivars

Field experiments were conducted in the eastern wheat belt of Western Australia in a dry year with and without irrigation (1987) and in a wet year (1988), comparing three cultivars of wheat differing in height and yield potential. The aim of the study was to determine the contribution of remobilisable stem dry matter to grain dry matter under different water regimes in old and modern wheats. Stem non-structural carbohydrate was labelled with 14C 1 day after anthesis and the activity and weight of this pool and the grain was measured at 2, 18 and 58 days after anthesis. Gutha and Kulin, modern tall and semi-dwarf cultivars respectively, yielded higher than Gamenya, a tall older cultivar in all conditions, but the percentage reduction in yield under water stress was greater for the modern cultivars (41, 34 and 23%). In the grain of Gamenya, the increase in 14C activity after the initial labelling was highest under water stress. Generally, loss of 14C activity from the non-structural stem dry matter was less than the increase in grain activity under water stress but similar to or greater than grain activity increase under well watered conditions. Averaged over environments and cultivars, non-structural dry matter stored in the stem contributed at least 20% of the grain dry matter.