Search

Background.Crop yield is a compound and complex character in breeding programs. A stable high yield is determined by the genotype, environmental impacts, and their interaction. A comprehensive assessment of cultivars based on their adaptability, plasticity and stability makes it possible to select among the studied assortment the most promising, potentially high-yielding and environmentally flexible plant forms adaptable to a wide range of environmental conditions.Materials and methods. Evaluation of 146 accessions representing two-row (subsp.distichonL.) and six-row (subsp.vulgare) barleys (Hordeum vulgareL.) was performed in 2015–2017 to measure the adaptability, stability, plasticity and homeostasis of barley yield. Experimental data were statistically processed using the methods of the two-way ANOVA and correlation analysis.Results and conclusion. It was established that barley yield formation was almost equally determined by the genotype (34.3%), environmental conditions (31.9%), and genotype × environment interactions (33,7%), showing that the tested barleys were relatively well adaptable to climate changes in the Northern Trans-Urals. Barley yield was more closely associated with grain weight per plant (r = 0.72) and the number of productive stems per area unit (r = 0.63), and to a lesser extent with seed germination rate in the field (r = 0.39) and 1000 grain weight (r = 0.37). Strong correlations were observed for the yield with the adaptability coefficient (r = 0.94), environmental plasticity index (r = 1.00), and compensatory capacity (r = 0.96). Cvs. ‘Abyssinian 14’ (k-23504, var.pallidum) and ‘Kharkovsky 70’ (k-23683, var.nutans) exhibited a set of adaptive and productive properties.

Background. The grain coat plays a major role in the development of rye cultivars with low levels of water-soluble pentosans (WSP). Grain coat thinness is a diagnostic trait for low WSP (arabinoxylans) content. To improve the technology of low-pentosan rye breeding, it becomes important to study the effect of changes in the anatomy of low-pentosan grains on morphological characteristics.Materials and methods. Grains with thin coats (transparent) were identified with the LFS-1 diaphanoscope in the populations of 7 commercial winter rye cultivars grown in Russian Federation. Anatomical and morphological features of seed coats were studied on thick- and thin-coated grains identified in the rye cultivars ‘Era’ and ‘Vyatka’. The thickness of grain coats and the aleurone layer were assessed according to L. N. Lyubarsky.Results and conclusions. In thin-coated rye grains, we found a reduction in the thickness of the pericarp and seed coats by 50–70% and in the aleurone layer by 32.1–39.6%, compared to thick-coated grains. With a constant cell size in “transparent” grains, a decrease in the thickness of the aleurone layer and coat occurs at the expense of the reduction in not only the cell walls, but also the intercellular space. The pericarp in the tissues of the second multicellular layer contains the bulk of the protective biologically passive WSP. It was proved that there were no significant changes in grain parameters, such as length, width and relative volume, depending on coat thinness. Significant differences were found in the 1000 grain weight. In “transparent” grains the index increased by 5.2–19.7%, compared with “nontransparent” ones.

Padi merupakan salah satu sumber karbohidrat utama bagi masyarakat Indonesia. Upaya pengembangan varietas baru sangat bergantung pada ketersediaan plasma nutfah sebagai sumber material genetik. Salah satu cara dalam pengembangan varietas baru melalui persilangan buatan untuk menciptakan keragaman dengan menggunakan kultivar lokal dan varietas/galur unggul. Tujuan penelitian ialah untuk mengeksplorasi korelasi, heterosis, aksi gen, dan heritabilitas arti luas pada delapan karakter padi, yang dapat digunakan dalam melakukan seleksi. Kegiatan persilangan buatan telah dilakukan dengan menggunakan satu galur unggul dan empat kultivar padi lokal yang memiliki karakter beragam. Empat populasi hasil persilangan (F1) ditanam menggunakan rancangan acak lengkap dengan empat ulangan, serta lima tetua (galur unggul dan padi lokal) sebagai pembanding. Hasil perhitungan korelasi menemukan bahwa terdapat satu variabel yang menunjukan korelasi pada hampir semua karakter yaitu bobot malai. Heritabilitas tinggi terdapat pada karakter umur panen, panjang malai, jumlah gabah permalai, bobot 1000 biji dan tinggi tanaman. Persilangan yang menunjukan fenomena heterosis negatif ialah pada B14081H-296 x Salak dan Dampak x Carogol sehingga memiliki umur panen yang lebih pendek dari rata-rata kedua tetua dengan aksi gen dominan sebagian dan aditif.

Grain-filling, as the final growth stage of rice, is sensitive to environmental temperature change. Previous studies mainly concerned about the effects of high temperature stress during grain-filling on rice growth, and most experiments were carried out with pot for cultivating rice and greenhouse for warming. This research investigated the response of rice grain-filling of superior spikelets (SS) and inferior spikelets (IS) of two japonica cultivars to elevated temperature during grain-filling stage under open-field warming conditions in lower reaches of Yangtze River Basin using free-air temperature enhancement facility. Results indicated that rice yield was not significantly changed by warming less than 4°C. SS and IS showed different responses to elevated temperature during the grain-filling stage, whereas there were similar trends between two cultivars and years. For SS, although elevated temperature enhanced its filling rate during the early grain-filling period, and caused a shorter grain-filling period and a lighter grain weight; for IS, elevated temperature improved its grain weight by enhancing its filling rate during middle and late grain-filling period due to the increased number of days with suitable temperature. For both SS and IS, key starch biosynthesis enzymes and indole-3-acetic acid content exhibited generally a similar dynamics trend with grain-filling rates, and these sink strength parameters presented higher levels under elevated temperature relative to natural temperature for IS during middle and late grain-filling period. Consequently, warming less than 4°C presented different influences on SS and IS; the improvement of IS filling under warming regime was associated with the intensification of grain sink strength.

The research was carried out with the aim to investigation the effects on grain yield and some seed characteristics of leaf, tassel removal and together treatments in maize during 2018 and 2019 years. The experiments were set up according to a Randomized Complete Block Design in a split-plot arrangement with three replicates, where cultivars were in the main plots while the practices were in subplots within the main plots using Bora (dent corn) and Karadeniz Yildizi (flint corn) maize cultivars. Effect on yield and seed characteristics of leaf (LR) and tassel removal (TR) and leaf x tassel removal interaction (LRxTR) were positive in both cultivars. The highest seed width (5.25 and 5.58 mm, respectively), seed length (9.89 and 10.21 mm, respectively), seed number per ear (642.2 and 669.6 number, respectively), 1000 grain weight (412.9 and 416.6 g, respectively), hectoliter weight (74.9 and 75.2 kg, respectively) and grain yield (1268.3 and 1334.8 kg da-1, respectively) were determined from the LRxTR interaction on dent corn in both years. However, YS+UA and UA treatments were included in the same statistical group. Generally, the lowest yield and seed characteristics were recorded in control treatment. The tassel removal treatment could be recommended due to its positive effects on yield and seed characteristics.

Background. Lodging has an extremely negative impact on barley yield: grain quality and planting properties are deteriorated, disease incidence increases, and mechanized harvesting becomes difficult, so it is important to find new sources of lodging resistance in barley and use them in crosses and breeding programs to develop non-lodging barley cultivars.Materials and methods. Experimental work was carried out in 2018 and 2019 at Federal Agricultural Science Center of the North-East (FASC North-East), Kirov. Yield structure components and lodging resistance levels were assessed for 29 accessions from the spring barley collection. The study was based on the International COMECON List of Descriptors for the Genus Hordeum L. (subgen. Hordeum) and Methodological Guidelines for the Study and Preservation of the World Collection of Barley and Oats.Results and conclusions. Lodging resistance was observed to have a strong correlation with yield (r = 0.72) and plant height (r = –0.60), and a medium correlation with tillering (r = 0.40) and number of nodal roots at maturation (r = 0.44). No relationship was found between lodging resistance and morphological features of the second lowest internode, which means that selection of non-lodging forms by these criteria will not be effective. Lodging-resistant accessions demonstrated higher yield, tillering, productivity, 1000 grain weight, and a longer and denser ear compared to nonresistant accessions. Accessions combining high yield with lodging resistance and a set of traits promising for breeding were identified: ‘Belgorodsky 100’, ‘Naran’ (k-30892), ‘Kazminsky’ (k-30926), ‘Shchedry’ (k-31046) (Russia); ‘Syabra’ (k-30917), ‘Raider’ (Belarus); ‘Odesssky 115’ (k-29010, Ukraine), ‘Mie’ (k-30379, Estonia), ‘Rodos’ (k-30256, Poland).

Background. Development of new highly adaptable triticale cultivars with high yield potential and environmental resistance to adverse factors of the Middle Amur region requires a study of the collection material. One of the priorities of such research is to identify effective sources and donors among triticale accessions according to the main yield components and economically useful traits.Materials and methods. The material was represented by spring triticale cultivars from the collection of the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR).Results. The following cultivars were identified as promising breeding sources: ‘AC Certa’, ‘Lana’, ‘Zolotoy Grebeshok’ and ‘Ulyana’ for their optimal yield in the Middle Amur region; ‘AC Certa’, ‘Zolotoy Grebeshok’, ‘Mykola’, ‘Korovai Kharkivsky’ and ‘Victoria’ for earliness; ‘Victoria’, ‘Rovnya’, ‘Kobzar’ (Ukraine), ‘Losinovske’, ‘Zgurivsky’ and ‘Sandio’ for plant height; ‘Lotos’, ‘Yarilo’, ‘ZG 186’, ‘Oberig Kharkivsky’, ‘Tleridal’ and ‘Sandio’ for ear length; ‘Lana’, ‘Ulyana’, ‘Lotos, ‘Yarilo’, ‘ZG 186’, ‘Pamyat Merezhko’, ‘Victoria’, ‘Kobzar’, ‘Oberig Kharkivsky’, ‘Tleridal’ and’ Sandio’ for the number of spikelets per ear; ‘AC Certa’, ‘Lana’, ‘Dagvo’, ‘Pamyat Merezhko’ and ‘Kobzar’ for the number of grains per ear; ‘Ukro’, ‘Lotos’, ‘Yarilo’, ‘Rovnya’ and ‘Kobzar’ for grain weight per ear; ‘Ukro’, ‘Skory’ and ‘Rovnya’ for grain size; ‘Ukro’, ‘Skory’ and ‘Rovnya’ protein content in grain; ‘Dagvo’, ‘Kobzar’ and ‘Sandio’ for lysine content in grain; ‘AC Certa’, ‘Lana’, ‘Skory’, ‘Lotus’, ‘Yarilo’, ‘ZG 186’, ‘Pamyat Merezhko’, ‘Victoria’, ‘Rovnya’, ‘Kobzar’, ‘Losinovske’, ‘Zgurivsky’, ‘Oberig Kharkivsky’, ‘Tleridal’ and ‘Sandio’ for resistance to lodging; ‘Lana’, ‘Pamyat Merezhko’, ‘Victoria Zgurivsky’, ‘Oberig Kharkivsky’ and ‘Tleridal’ for disease resistance.Conclusion. The selected accessions can be used in breeding programs of the Middle Amur region and other regions of the country.

Background and Aims The pericarp weight comprises Methods Two spring wheat cultivars contrasting in kernel weight (Bacanora and Kambara) were sown in field conditions during seasons 2012–13 and 2014–15. Both genotypes were grown under contrasting plant density (control, 370 plants m–2; and low plant density, 44 plants m–2) and night temperatures, i.e. at ambient and increased (>6 °C) temperature for short periods before and after anthesis. From anthesis onward, grains were harvested every 3 or 4 d. Grain samples were measured and the pericarp was removed with a scalpel. Whole grain and pericarp fresh and dry weight were weighed with a precision balance. At harvest, 20 grains from ten spikes were weighed and grain dimensions were measured. Key Results Fresh weight, dry matter and water content of pericarp dynamics showed a maximum between 110 and 235 °Cd. Maximum dry matter of the pericarp ranged between 4.3 and 5.7 mg, while water content achieved values of up to 12.5 mg. Maximum values and their timings were affected by the genotype, environmental condition and grain position. Final grain weight was closely associated with maximum dry matter and water content of the pericarp. Conclusions Maximum pericarp weight is a determinant of grain weight and size in wheat, which is earlier than other traits considered as key determinants of grain weight during grain filling. Better growing conditions increased maximum pericarp weight, while higher temperature negatively affected this trait.

The state, selection achievements of triticale culture from Poland, its distribution, acreage, and yield are analyzed. In 2007 – 2009, 52 varieties of winter triticale were studied, in 2013 – 2016 — 17 varieties, and in 2018 – 2019 — 20 new varieties from Poland were tested in the Moscow oblast’. Polish short-stemmed varieties Grenado Argento and Korvetto under the conditions of Moscow and other regions have a complex of economically valuable features and properties, so they are used in the selection programs of scientific centers in Russia. In the 2017 – 2019, the study of the gene pool in the Moscow oblast’ identified Polish varieties Felo (k-4010), Hortense (k-4012), Preco/Kill/Rex/Aos/Rex, having a moderately short stem (95 – 110 cm), increased resistance to winter stress (7 – 9 points), snow mold (5 – 7 points) and brown rust (9 points), as well as a large, well-watered ear (56 – 59 achenes) with a grain weight of 2.8 – 3.1 g, 1000 grains — 50 – 52 g, and grains/m2 — 860 – 890 g. In 2007 – 2018 more than 100 Polish cultivars were studied using a set of indicators. The most valuable of them were used in the development of new, more advanced lines and varieties of triticale. Created with the introduction in the State register of highly productive (more than 10 tons/ha of grain) winter variety triticale Kapella. The source material for its production by the method of ecological mutagenesis was a variety of spring triticale from Poland (k-2045), which has a set of valuable indicators.

The research on wheat accessions was carried out in order to evaluate their grain characteristics. Experiment was set in the agro-ecological conditions of Banja Luka in two experimental years (2015/16 and 2016/17). Ten obsolete wheat cultivars (Brkulja, Ličanka, Partizanka, Vuka, Talijanka, Šiđanka, Orašanka, Lozničanka, Dokučajevskaja and Nemcitaevskaja) and two landraces (Podrašnica and Previja) were used. Following grain characteristics were evaluated: grain length (mm), grain width (mm), grain thickness (mm), grain volume (mm3), grain surface area (mm2), thousand grain weight (g) and grain protein content (%). Significant interactions were found for most of these traits. The relationship between traits was established by correlation analysis. In this study genotypes Brkulja and Šiđanka showed promising for most of the grain characteristics, while Vuka and Partizanka obtained the highest grain protein content.

Field experiments were conducted at Sakha, Kafr El-Sheikh, Egypt; to investigate the effect silica combined with mineral nitrogen on rice yield, and stem borer Chilo agamemnon Bles. Applying potassium ore combined with 92 kg N/fed. Produced the highest panicles/m2 (814.31) compared to other silica applications or lower nitrogen levels. The same trend was observed with panicle weight. One-thousand grain weight was higher in Egyptian hybrid 1 than in Giza 178. The grain yields were also highest with potassium ore for both cultivars at the rate of 92 kg N/fed. Rice stem borer infestation was higher in hybrid than in inbred cultivar. Both dead hearts and white heads gradually increased by the increase of nitrogenous applications; from 2.65 to 4.14 % dead hearts, and from 3.77 to 5.59 % white heads due to nitrogenous increase from 23 to 92 kg/fed., respectively. The highest dead hearts (4.92 & 5.28) and white heads (9.42 & 7.06 %) were detected in plots without silica. From the data of this experiment, it could be concluded that Egyptian hybrid 1 yielded more than Giza 178, particularly with using 92 kg N/fed., combined with potassium ore at 500 kg/fed.. It was found that silica applications reduced the stem borer infestation, regardless of the cultivar and nitrogen rates.

Purpose and objectives - to determine the breeding value of spring barley cultivars and lines.Materials and methods: Twenty-two cultivars and 3 lines of spring barley were taken as the test material. The field experiments were carried out in the competitive variety trial nursery in compliance with the method of state variety trials. The forecrop was grain pea. The plot area was 10 m2; the experiments were carried out in 4 replications. Barley was sown with a breeding seeder SSFK-7. The yield, growing period length, lodging resistance, performance and its structural elements were determined. Calculus of variations analysis of variance were performed in STATISTICA 10 and EXCEL as BA Dospekhov described.Results and discussion: The peculiarities of 22 cultivars and 3 lines of spring barley were described by expression levels of the following quantitative traits: morpho-biological (performance, total and productive tillering capacity, spikelet and grain number per spike, spike length, grain weight from the main ear and lateral stalks) and economic (yield, growing period length, lodging resistance) ones.The variability of quantitative traits of the accessions under investigation was determined. In particular, the plant height variability was low (9.5%), the spike length and grain weight from the main spike variabilities were medium (15.6 and 19.5%, respectively), and the variability of other traits were high.The analysis distinguished intensive high-yielding cultivars Margret, Grace, Avhur, Datcha, Khors, and Troian and the line 14-561 (5.07–4.84 t/ha); lodging-resistant cultivars Amil, Troian (Lider), Datcha, and Grace and line 15-139; and high performance cultivars Amil, Khors, Hatunok, Akhiles, and Krasen.Conclusions. As a result of determining the characteristics of the spring barley accessions with high levels of expression of quantitative morpho-biological and economic traits, the breeding value of cultivars and lines suitable for combination breeding was evaluated.

The aim of this work was to investigate the genotypic variation of thirty five bread wheat genotypes as well as to clarify the association between grain yield and the other important agronomic traits. Two field experiments were carried out in the Experimental Farm of Genetic Resources Department, Bahteem Agricultural Research Station, Egypt during 2015-2016 and 2016-2017 growing seasons. Thirty two wheat landraces collected from eleven Districts in Egypt, in addition to three local cultivars were evaluated for earliness traits, plant height, yield and its components. The results indicated significant differences among the evaluated wheat genotypes for all investigated traits during the two seasons. The highest grain weight/plant and contributing traits were assigned for genotypes; G3, G8, G18, G27, G29, G33 and G35 at two growing seasons. The phenotypic variance (σ2ph) was found slightly higher than the genotypic variance (σ2g) for all studied traits under two seasons, and accordingly, phenotypic coefficient of variation (PCV) values were relatively greater than genotypic coefficient of variation (GCV) values for all traits. Heritability in broad sense (h2b) values were high for plant height (90.63 and 97.81 %), number of grains/spike (95.33 and 84.66 %), 1000-grain weight (76.42 and 84.03 %), days to heading (77.4 and 87.06 %) and days to maturity (86.18 and 66.56 %) in 1st and 2nd seasons, respectively. Besides, it was low in 1st season (43.38 %) and high in 2nd season (71.91 %) for grain weight/plant, whereas it was moderate for number of spikes/plant (52.87 and 58.09 %) in 1st and 2nd seasons, respectively. Furthermore, positive genotypic and phenotypic correlations were found between studied traits and grain weight/plant during two growing seasons except days to heading. Additionally, path analysis was calculated and it was found that the direct effects on wheat grain yield of all studied traits were positive in both seasons except days to 50% heading at two seasons and days to maturity and plant height at the second season.

Background. To obtain sustainable and high rice yields, it is crucial to select the best cultivars adapted to the cultivation in the main rice-growing areas. Combining high yields and technological quality indicators of wholegrain and milled rice is of vital importance. The practical solution of such an important task largely depends on successful breeding work. Materials and methods. Eight rice cultivars were evaluated in competitive trials in 2016–2018. Experimental plots were arranged within the rice irrigation system of the All-Russian Rice Research Institute in Belozerny Settlement, Krasnodar Territory. During the growing season, the following traits were visually evaluated: plant density, resistance to lodging, disease and pest infestation, and uniformity of crops. Screening and discarding operations on the plots planned for harvesting were followed by making model sheaves of 10–15 plants each for biometric analysis. Technological characteristics of wholegrain and milled rice were measured according to GOST 10843-76 and GOST 10987-76 standards. The results were mathematically processed and proved reliable. Results. Four promising cultivars ‘VNIIR 10244’, ‘VNIIR 10275’, ‘VNIIR 10279’ and ‘VNIIR 10282’ with a set of economically useful traits significantly exceeding the standard reference (st) ‘Flagman’ were selected. Their yield was 9.0 t/ha; 1000 grain weight: 29.3; 28.1; 30.4 and 26.3 g; hull percentage: 17.7; 19.7; 19.5 and 21.4%; and wholegrain content: 88.5; 93.5; 89.4 and 97.8%, respectively. Significantly high yields of these cultivars are due to the optimal number of fertile spikelets (150–160 pcs), panicle density (9.8–12.6 pcs/cm), and significant weight of grain from the main panicle (3.7–4.4 g), with an average sterility of 14.2–20.3%. A close positive correlation of yield traits with wholegrain content was observed in cvs. ‘VNIIR 10282’, ‘VNIIR 10279’, ‘VNIIR 10276’ and ‘VNIIR 10275’ (r = 0.92– 0.98). An inverse relationship between yield and kernel fissuring was observed in most genotypes, which testifies to the potential possibility of increasing their yield without the risk of reducing milled rice yield or wholegrain content. Conclusion. The evaluation resulted in identifying four promising rice cultivars: ‘VNIIR 10244’ and ‘VNIIR 10279’ (large-grain), ‘VNIIR 10275’ and ‘VNIIR 10282’ (medium-sized grain). They significantly exceeded the standard reference ‘Flagman’ in a set of economically useful traits: yield and its structural elements as well as technological characters of wholegrain and milled rice quality. The best of the selected genotypes according to the optimal ratio of the studied traits will be submitted to the State Variety Trials in 2019–2020.

Low light is a common environmental factor that adversely affects rice yields. This study was conducted to evaluate the combined effect of hill density and nitrogen (N) fertilizer rate on yield attributes in hybrid rice under low-light conditions. Field experiments were conducted in 2014 and 2015. Two hybrid rice cultivars (Y-liangyou 1 and Luoyou 9348) were grown under combinations of three hill density levels (high, 40 × 104 hills ha−1; moderate, 27 × 104 hills ha−1; low, 14 × 104 hills ha−1) and two N rate levels (high, 240 kg ha−1; moderate, 143–148 kg ha−1), and shaded from heading to maturity. Grain yield was highest in the combination of high hill density and moderate N rate and significantly declined with decreasing hill density combined with increasing N rate for both cultivars in both years. Averaged across two cultivars and two years, grain yield declined by about 4% for each 10% decrease in hill density combined with each 10% increase in N rate. A significant reduction in spikelet filling percentage was observed with decreasing hill density combined with increasing N rate in Y-liangyou 1 in 2015 and Luoyou 9348 in 2014. The same trend was observed for grain weight in Y-liangyou 1 in 2014 and Luoyou 9348 in 2015. These results indicate that adopting the practice of decreasing hill density combined with increasing N rate can result in poor grain filling and consequently yield decline in hybrid rice under low-light conditions.

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.

To understand the effects of source-sink relationships on rice yield response to elevated CO2 levels (eCO2), we conducted a field study using a popular japonica cultivar grown in a free-air CO2 enrichment environment in 2017–2018. The source-sink ratio of rice was set artificially via source-sink treatments (SSTs) at the heading stage. Five SSTs were performed in 2017 (EXP1): cutting off the flag leaf (LC1) and the top three functional leaves (LC3), removing one branch in every three branches of a panicle (SR1/3) and one branch in every two branches of a panicle (SR1/2), and the control (CK) without any leaf cutting or spikelet removal. The eCO2 significantly increased grain yield by 15.7% on average over all treatments; it significantly increased grain yield of CK, LC1, LC3, SR1/3, and SR1/2 crops by 13.9, 18.1, 25.3, 12.0, and 10.9%, respectively. The yield response to eCO2 was associated with a significant increase of panicle number and fully-filled grain percentage (FGP), and the response of crops under different SSTs was significantly positively correlated with FGP and the average grain weight of the seeds. Two SSTs (CK and LC3) were performed in 2018 (EXP2), which confirmed that the yield response of LC3 crops (25.1%) to eCO2 was significantly higher than that of CK (15.9%). Among the different grain positions, yield response to eCO2 of grains attached to the lower secondary rachis was greater than that of grains attached to the upper primary rachis. Reducing the source-sink ratio via leaf-cutting enhanced the net photosynthetic rate response of the remaining leaves to eCO2 and increased the grain filling ability. Conversely, spikelet removal increased the non-structural carbohydrate (NSC) content of the stem, causing feedback inhibition and photosynthetic down-regulation. This study suggests that reducing the source-sink ratio by adopting appropriate management measures can increase the response of rice to eCO2.

There is concern over the impact of global warming on rice production due increased heat stress, coupled with decreased relative humidity (RH). It is unknown how rice yield and quality are affected by heat stress and decreased RH during the grain filling stage. We conducted experiments in controlled growth chambers on six rice cultivars, varying in heat tolerance using 12 combinative treatments of three factors: two RH levels (75% and 85%), three temperature levels (the daily maximum temperature at 33 °C, 35 °C, and 37 °C), and two durations (8 d and 15 d after anthesis). Results showed that RH75% with temperature treatments significantly reduced grain weight, which was higher than RH85%. The same trend was also observed for both head rice rate and chalkiness. R168 was the most heat-tolerant cultivar, but it still had some differences in grain weight, head rice rate, and chalkiness between the two RH regimes. The lower RH was most detrimental at 35 °C, and to a lesser extent at 33 °C, but had a negligible effect at 37 °C. Our results provide a better understanding of temperature and RH’s interaction effects on rice quality during the grain filling stage, suggesting that RH should be considered in heat tolerance screening and identification to facilitate rice breeding and genetic improvement.

Rice yield measurement in paddy fields is of great importance for regulating the balance of national grain supply and demand, but it is laborious and time consuming. In this paper, a fast yield measurement method based on rice panicle attributes and modelling is presented. To develop the method, first, the panicle attributes that are the main determinants of grain weight were identified through regression analysis. Second, the correlations between grain area and weight parameters were established and verified for different cultivars. Finally, a “five-point calibration model” was developed to rapidly estimate the weight parameters, and the estimated values and actual yields were compared. The results showed that the image processing method was capable of extracting the area of grain per panicle more accurately than other methods and that it was suitable for different cultivars: the lowest accurate extraction rate was 90.50%. All the coefficient of determination (R2) values of the weight prediction models of rice panicle grain area and the weight parameters were greater than 0.80, and the highest R2 value was 0.96. The R2 values of the “five-point calibration model” of grain area and grain weight were all greater than 0.99. When the predicted yields calculated by the “five-point calibration model” were compared with the actual yields, the relative errors ranged from 1.36% to 8.64%; i.e., they were all less than 10%. These results indicated that rice panicle 2D image modelling could enable rapid yield predictions in the field.

Background. An extremely important task today is to develop new hulless barley cultivars, capable of yielding large and high-quality grain harvests, and introduce them into agricultural production. Objective. The purpose was to study three hulless barley cultivars ‘Omsky golozerny 2’, ‘Omsky golozerny 4’ and ‘Maysky’, developed at Omsk Agrarian Scientific Center, in order to describe their agrobiological characteristics.Materials and methods.The experimental part of the work was carried out in 2015–2017 on the experimental fields of Omsk ASC in the southern forest steppe (third crop rotation after the wheat predecessor; fourth crop after fallow). There were 4 replications on the plot of 10 m2. The seeding rate was 4 million viable seeds per 1 ha. Agricultural practice used in the experiments was conventional for West Siberia. Parameters of stability and plasticity were calculated according to Eberhart and Russell, Wricke; adaptability, according to Zhivotkov; homeostasis, according to Khangildin; stress tolerance and compensatory ability, according to Rossielle and Hemblin.Results. Many years of breeding work at Omsk ASC resulted in the development of three hulless barley cultivars: ‘Omsky golozerny 2’ (listed in the State Register of the Russian Federation for regions 9, 10 and 11), ‘Omsky golozerny 4’ (submitted for the State Crop Variety Trials in 2017), and ‘Maysky’ (not included in the State Register). The new hulless barley cultivar ‘Omsky golozerny 4’, considering its higher productivity (+1.36 g to the reference in 1000 grain weight, and +0.73 t/ha to cv. ‘Maysky’), in the yield of nutrients per area unit equaled the reference ‘Omsky golozerny 2’, but exceeded ‘Maysky’ (+47.2 kg/ha of protein, +390 kg/ha of starch, and +42.4 kg/ha of crude fat). ‘Omsky golozerny 4’ was also characterized by stability (stability = 4.8), increased compensatory ability (3.29) and adaptability (103%). There was an increase in productivity with improved growing conditions (ecological plasticity = 1.25). ‘Maysky’ had higher stress tolerance (–1.35), while the reference ‘Omsky golozerny 2’ showed increased homeostasis (0.118). Thus, ‘Omsky golozerny 4’ exceeded the previous two cultivars in adaptability and stability.

Agronomic and morphological characteristics of fourteen (14) local upland rice cultivars of Arakan Valley, Cotabato, Philippines were evaluated to determine desirable traits in improving upland rice production and for future breeding purposes. Traditional upland rice seeds differ in shape, size, colour and aroma. Azucena and Kapalawan have longer grains of 9-12 mm and the smallest grain was from Mal-os of 5.5 - 8 mm.  Bungulan, Ulipapa, and Magalitok cultivars have medium size grain of about 8-11 mm. Azucena and Bungulan have translucent caryopsis and aromatic. Mubpon had medium grain size and semi-aromatic and Dinorado had aromatic pinkish to purplish caryopsis and medium size grain. Hinumay and Azucena have the tallest height among rice cultivars with 126.5 and 127 cm, respectively.  Malundiang got the shortest height of 91 cm. Kawilan got the highest number of tillers with 6.5 and 5 panicles per plant. Malundiang cultivar flowered early at 65-70 days while Azucena and Kawilan have late flowering of more than 90 days after planting. Magalitok  had the longest panicle with 31.06 cm and the shortest panicle was measured from Malundiang with 16.63 cm. Ulipapa had the highest 1,000-grain weight of 28.54 g while Manisi got the lowest grain weight of 15.33 g only.  The result of the study showed variation in the agro-morphological characteristics of the indigenous upland rice. Bungulan, Ulipapa, Malundiang, Mubpon, Sinulid and Kawilan have potential agronomic characteristics in improving upland rice production in the IP community. Dinorado, Hinumay, and Azucena have been planted by the local farmers for its desirable grain characteristics and aroma. https://doi.org/10.26803/ijhss.11.2.2

The experiment was established at the experimental field of the Dr. Đorđe Radić Secondary School of Agriculture and Chemistry in Kraljevo (Serbia) during the 2010/11, 2011/12 and 2012/13 growing seasons. The objective of the research was to evaluate the effect of genotype and the environment on the grain yield of winter barley cultivars (‘Jagodinac’, ‘Maksa’, ‘Rekord’, ‘NS 565’ and ‘NS 525’). The following characteristics were analysed: grain yield, 1,000 grain weight, test weight and plant height. The average grain yield of all cultivars in the 2010/11 growing season was significantly greater than in the following years, mostly as the result of highly favourable weather conditions at major stages of plant development. ‘Jagodinac’, ‘NS 565’ and ‘NS 525’ gave significantly higher grain yields in all years compared to ‘Maksa’ and ‘Rekord’. Averaged across years, significantly higher values for 1,000 grain weight and test weight were found in ‘NS 565’ and ‘Rekord’, respectively. In all years, plant height was significantly greater in ‘Jagodinac’ than in the other cultivars. Different responses of cultivars to variable agroenvironmental conditions in terms of 1,000 grain weight and test weight require the use of a number of cultivars in the crop structure.

The current lack of efficient methods for high throughput field phenotyping is a constraint on the goal of increasing durum wheat yields. This study illustrates a comprehensive methodology for phenotyping this crop's water use through the use of the two-source energy balance (TSEB) model employing very high resolution imagery. An unmanned aerial vehicle (UAV) equipped with multispectral and thermal cameras was used to phenotype 19 durum wheat cultivars grown under three contrasting irrigation treatments matching crop evapotranspiration levels (ETc): 100%ETc treatment meeting all crop water requirements (450 mm), 50%ETc treatment meeting half of them (285 mm), and a rainfed treatment (122 mm). Yield reductions of 18.3 and 48.0% were recorded in the 50%ETc and rainfed treatments, respectively, in comparison with the 100%ETc treatment. UAV flights were carried out during jointing (April 4th), anthesis (April 30th), and grain-filling (May 22nd). Remotely-sensed data were used to estimate: (1) plant height from a digital surface model (H, R2 = 0.95, RMSE = 0.18m), (2) leaf area index from multispectral vegetation indices (LAI, R2 = 0.78, RMSE = 0.63), and (3) actual evapotranspiration (ETa) and transpiration (T) through the TSEB model (R2 = 0.50, RMSE = 0.24 mm/h). Compared with ground measurements, the four traits estimated at grain-filling provided a good prediction of days from sowing to heading (DH, r = 0.58–0.86), to anthesis (DA, r = 0.59–0.85) and to maturity (r = 0.67–0.95), grain-filling duration (GFD, r = 0.54–0.74), plant height (r = 0.62–0.69), number of grains per spike (NGS, r = 0.41–0.64), and thousand kernel weight (TKW, r = 0.37–0.42). The best trait to estimate yield, DH, DA, and GFD was ETa at anthesis or during grain filling. Better forecasts for yield-related traits were recorded in the irrigated treatments than in the rainfed one. These results show a promising perspective in the use of energy balance models for the phenotyping of large numbers of durum wheat genotypes under Mediterranean conditions.

In recent years, considerable efforts have been made to understand the factors controlling grain weight in wheat. In addition to sink capacity, the supply of assimilates for developing grain determines the weight of the grain. The current photosynthesis of the flag leaf is the most important source of assimilation, and the onset and rate of senescence are important factors for determining grain yield. Hence stress induced leaf senescence can reduce the supply of assimilates for grains. Under such conditions, assimilate contributions of stored non structural carbohydrates in stem and photosynthesis of non foliar parts of the plant such as spike are crucial for grain development. Non structural carbohydrates in wheat stem have been estimated and efforts have been made to reveal the mechanisms of assimilate partitioning. The hormone levels and activities of enzymes involved in assimilate partitioning and carbohydrate metabolism in wheat stem and grains have been significantly correlated with grain filling in wheat. Remobilization efficiency of stem reserves is increased under heat or drought stress along with increase in the proteins associated with senescence and ROS handling in the tolerant cultivars. The heat and drought tolerant wheat cultivars have a higher WSC content in stem, higher mobilization efficiency, longer duration of grain filling and stronger sink activity. However, some of the key issues such as intra-spike assimilation distribution have not been sufficiently addressed. This review has been compiled for information related to assimilate supply to the developing wheat grain under stress conditions and also enlists opportunities to translate this knowledge into traits for improvement of climate resilience in wheat.

Soybean yield depends on the selection of cultivars, soil fertility, applied cultivation practices, and agroclimatic conditions over the years. High-quality and timely primary tillage is essential for stable development and high yields of soybean plants. The effect of autumn and spring primary tillage on soybean yield and 1000-grain weight was examined in a three-year study (2013-2015). The trial included cultivars with different maturity periods, developed at the Institute of Field and Vegetable Crops Novi Sad: Valjevka and Galina 0 maturity group, Sava and NS Maximus I maturity group, Rubin and Venera II maturity group. Trial subplots were prepared using different periods of primary tillage, which was conducted in autumn (November, 01–05) and spring (March, 25–31). The highest yields and 1000-grain weight were obtained after autumn primary tillage in all the three study years. Yield decrease by 2.72% to 38.91% and 1000-grain weight decrease of 1.33%-11.93% were recorded after spring primary tillage Prinos soje zavisi od izbora sorte, plodnosti zemljišta, primijenjenih agrotehničkih mjera i agroklimatskih uslova u pojedinim godinama. Kvalitetna i pravovremena osnovna obrada zemljišta je uslov za normalan razvoj biljaka soje i ostvarenje visokoh prinosa. U trogodišnjim istraživanjima (2013-2015) proučavan je uticaj jesenje i proljećne osnovne obrade na prinos i masu 1000 zrna soje. U ogledu su bile zastupljene sorte soje Instituta za ratarstvo i povrtarstvo Novi Sad, različite dužine vegetacionog perioda: Valjevka i Galina–0 grupe zrenja, Sava i NS Maximus–I grupe zrenja) i Rubin i Venera, II–grupe zrenja. Podparcele u ogledu bile su sa različitim vremenom osnovne obrade zemljišta. Osnovna obrada je vršena u jesenjem periodu (01-05. novembra) i u proljećnom periodu (25–31. mart). Jesenjom osnovnom obradom zemljišta za proizvodnju soje ostvareni su najviši prinosi i najviša vrijednost za masu 1000 zrna soje, u sve tri istraživane godine. Kod proljećne osnovne obrade smanjenje prinosa kretalo od 2,72 % do 38,91 % i smanjenje mase 1000 zrna u pojedinim godinama od 1,33 % do 11,93 %.

Wheat (Triticum aestivum L.) is an important cereal crop globally as well as in India and yield improvement programs encounter a strong impediment from ever-evolving rust pathogens. Hence, durable rust resistance is always a priority trait for wheat breeders globally. Grain weight, represented as thousand grain weight (TGW), is the most important yield-contributing trait in wheat. In the present study high TGW has been transferred into two elite Indian wheat cultivars PBW343 and PBW550 from a high TGW genotype, Rye selection 111, selected from local germplasm. In the background of PBW343 and PBW550, an increase in TGW upto 27.34 and 18% was observed, respectively (with respect to recipient parents), through conventional backcross breeding with phenotypic selections in 3 years replicated RBD trials. Resistance to leaf rust and stripe rust has been incorporated in the high TGW version of PBW550 through marker assisted pyramiding of stripe rust resistance gene Yr15 using marker Xuhw302, and a pair of linked leaf rust and stripe rust resistance genes Lr57-Yr40 using marker Ta5DS-2754099_kasp23. Improved versions of PBW550 with increased TGW ranging from 45.0 to 46.2 g (up to a 9% increase) and stacked genes for stripe and leaf rust resistance have been developed. This study serves as proof of utilizing conventional breeding and phenotypic selection combined with modern marker assisted selection in improvement of important wheat cultivars as a symbiont of conventional and moderan techniques.

This research was carried out by using 8 oat landraces and 9 registered oat cultivars sown in randomized complete block design with four replications between 2006-2008 years in Kahramanmaras conditions. In the study, it was aimed to evaluate the genotypes in terms of some morphological and agricultural characteristics, as well as to determine the genetic progress achieved in registered varieties in terms of some agricultural traits according to the years they were registered. In the research, grain filling period, sowing-maturity duration, number of panicle in m2, plant height, panicle height, grain number per panicle, grain weight per panicle, grain filling ratio, grain filling index and protein ratio in grain were investigated. According to the mean of two years, except for number of panicle in m2, grain weight per panicle, grain number per panicle, 1000 grain weight and protein ratio in grain genotypes were significantly different for all investigated traits., Bu araştırma Kahramanmaraş koşullarında, 2006-2008 ürün yıllarında tesadüf blokları deneme desenine göre 4 tekrarlamalı olarak ekilen 8 yerel ve 9 tescilli çeşit kullanılarak yürütülmüştür. Araştırmada, genotiplerin bazı morfolojik ve tarımsal özellikler bakımından değerlendirilmesi aynı zamanda bazı tarımsal özellikler bakımından tescilli çeşitlerde tescil edildikleri yıllara göre sağlanan genetik ilerlemenin belirlenmesi amaçlanmıştır. Denemede; tane dolum periyodu, ekim-olgunlaşma süresi, m2’deki salkım sayısı, bitki boyu, salkım uzunluğu, salkımdaki tane sayısı, salkımdaki tane ağırlığı, tane dolum oranı, tane dolum indeksi ve tanede protein oranı incelenmiştir. İki yıllık ortalama sonuçlarına göre metrekaredeki salkım sayısı, salkımdaki tane ağırlığı, salkımdaki tane sayısı ve tanedeki protein oranı dışındaki özellikler yönünden genotipler önemli ölçüde farklı bulunmuştur.

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 a higher grain number per spike (GN) and occasionally higher grain weight (GW) (main numerical components of the yield). This task could be facilitated with the use of molecular markers such us single nucleotide polymorphism (SNP). In this study, quantitative trait loci (QTL) for GW, GN and spike fertility traits related to GN determination were mapped using two double haploid (DH) populations (Baguette Premium 11 x BioINTA 2002 and Baguette 19 x BioINTA 2002, BP11xB2002 and B19xB2002). Both populations were genotyped with the iSelect 90K SNP array and evaluated in four (BP11xB19) or five (B19xB2002) environments. We identify a total of 305 QTL for 14 traits, however 28 QTL for 12 traits were considered significant with an R2 > 10% and stable for being present at least in three environments. There were detected eight hotspot regions on chromosomes 1A, 2B, 3A, 5A, 5B, 7A and 7B were at least two major QTL sheared confident intervals. QTL on two of these regions have previously been described, but the other six regions were never observed, suggesting that these regions would be novel. The R5A1 (QSL.perg-5A, QCN.perg-5A,QGN.perg-5A) and R5A.2 (QFFTS.perg-5A, QGW.perg-5A) regions together with the QGW.perg-6B resulted in a final higher yield suggesting them to have high relevance as candidates to be used in MAS to improve yield.Author contribution statementKey message28 stable and major QTL for 12 traits associated to spike fertility, GN and GW were detected. Two regions on 5A Ch., and QGW.perg-6B showed direct pleiotropic effects on yield.

Wheat stem sawfly, Cephus cinctus Norton, is an economically serious pest of cereals grown in North America. Barley cultivars were previously planted as resistant crops in rotations to manage C. cinctus, but due to increasing levels of injury to this crop, this is no longer a valid management tactic in Montana. Therefore, we aimed to understand antixenosis (behavioral preference), antibiosis (mortality), and potential yield compensation (increased productivity in response to stem injuries) in barley exposed to C. cinctus. We examined these traits in eight barley cultivars. Antixenosis was assessed by counting number of eggs per stem and antibiosis was assessed by counting infested stems, dead larvae, and stems cut by mature larvae. Potential yield compensation was evaluated by comparing grain yield from three categories of stem infestation: 1) uninfested, 2) infested with dead larva, and 3) infested cut by mature larva at crop maturity. We found the greatest number of eggs per infested stem (1.80 ± 0.04), the highest proportion of infested stems (0.63 ± 0.01), and the highest proportion of cut stems (0.33 ± 0.01) in ‘Hockett’. Seven out of eight cultivars had greater grain weight for infested stems than for uninfested stems. These cultivars may have compensatory responses to larval feeding injury. Overall, these barley cultivars contain varying levels of antixenosis, antibiosis, and differing levels of yield compensation. Our results provide foundational knowledge on barley traits that will provide a framework to further develop C. cinctus resistant or tolerant barley cultivars.

The research was established to determine the seed yield and yield component of some Amaranthus spp. varieties (Helios, Sterk and Ultra) in arid and irrigation conditions with three replications according to split plot experiment design in 2017-2018 years. In the study, plant height, stem diameter, panicle height, panicle ratio, stem yield, seed yield, biological yield, harvest index and 1000 grain weight of Amaranthus spp. varieties were determined. According to research results, the effect of years (except for stem diameter, panicle ratio and 1000 grain weight), cultivars and growing conditions (except for 1000 grain weight) on investigated parameters differed significantly. Accordingly, the highest stem, seed and biological yields were determined in Sterk variety, and harvest index was Helios and Sterk variety. Considering the two-year average data, the stems, seeds and biological yields of the cultivars were higher in water than dry conditions. When evaluated in terms of years, seed yield and harvest index were higher in 2017, plant height, panicle height, stem yield and biological yield values were higher in 2018. As a result, it has been demonstrated that the seed yield of Sterk variety grown in aqueous conditions is the most suitable variety for the region.

To increase the yield potential while limiting the environmental impact of N management practices is an important issue in rice cultivation. The large-grain rice cultivar Akita 63 showed higher N-use efficiency for grain production. To elucidate this, we analyzed yield characteristics of Akita 63 in comparison with those of a maternal cultivar, Oochikara with a large grain, a paternal cultivar, Akita 39 with a normal grain, and a Japanese leading cultivar, Akitakomachi. The yields of Akita 63 were 20% higher than those of Oochikara and Akita 39, and 50% higher than those of Akitakomachi for the same N application. Akita 63 showed superior N uptake capacity. Whereas a trade-off between single grain weight and grain number was found for Oochikara, Akita 63 did not show such a relationship. The success in Akita 63 breeding was due to overcoming such a trade-off. Akita 63 had the large-grain alleles of GS3 and qSW5. Thus, an enlargement of grain size can have a great impact on an increase in yield with improved N-use efficiency. However, an enlargement of sink capacity led to source limitation. Thus, both sink and source improvements are essential for a further increase in the yield of today’s high-yielding cultivars.

Thousand grain weight (TGW) is one of the three crucial determinants of wheat (Triticum aestivum) grain yield. The identification of functional genes and development of closely linked markers are urgently needed for wheat yield improvements. In this study, quantitative trait locus (QTL) mapping for TGW was carried out using one RIL population in four environments. A total of 8 QTL controlling TGW were detected across four chromosomes. Of them, QGW4B.4-17 was confirmed as a major and stable QTL for TGW increases of 2.19–3.06 g and high PVE of 22.5–36.3% in three environments. It was located in an interval (Rht1-TaGW-4B) of 2 Mb in physical distance that contains the Rht1 locus. Three high-confidence (HC) genes were predicted as potential candidates according to their annotated functions and expression profiles. Furthermore, a cleaved amplified polymorphic sequence (CAPS) marker, TaGW-4B, was developed and verified in a panel of 205 wheat cultivars and showed a highly significant correlation with TGW, demonstrating high value for efficient marker-assisted selection. The study provided a basis for cloning the functional genes underlying the QTL and a practical and accurate marker for molecular breeding.

Eight dryland winter wheat cultivars (Triticum aestivum L.), which were widely cultivated from the 1940s to the 2010s in Shaanxi Province, China, were selected and grown in plots, and two water treatments (irrigation and drought) were used to identify the contribution of ears, leaves and stems to grain weight and grain number associated with cultivar replacement. The plant height and stem dry weight of the dryland wheat decreased significantly during the cultivar replacement process, but there was a remarkable increase in the dry matter translocation of stems under irrigation. Shaded-ear and defoliation treatment could decrease the grain number and grain weight, and the grain weight was more influenced. Both the leaf and ear are important photosynthetic sources for dryland wheat, and the contribution of ear assimilates showed a significant increase over time; however, the contribution of leaf assimilates showed a negative correlation with cultivation over time. The accumulation of stem assimilates and ear photosynthesis both increased the grain weight potential. In the future breeding process, cultivars with more assimilates stored in the stem and greater assimilative capacity of ears, especially a greater contribution of ear assimilates, are expected to increase the grain yield.

O objetivo deste trabalho foi avaliar a influência da temperatura e precipitação no desempenho agronômico de cultivares de soja nos municípios de Tangará da Serra e Diamantino, MT. Os experimentos foram realizados na safra 2012/13. O delineamento experimental foi blocos casualizados fatorial 2x4x6. Sendo dois locais, quatro épocas de semeadura (05/10/2012; 20/10/2012; 05/11/2012 e 20/11/2012) e seis cultivares de soja (AS7307, ANTA 82, TMG 1179, P98Y30, TMG 132 e M-SOY 9144), totalizando 48 tratamentos e três repetições. Foram realizadas as seguintes avaliações: número de vagens por planta, número de grãos por vagem, massa de mil grãos, produtividade e balanço hídrico climatológico sequencial diário. Os resultados obtidos foram submetidos à análise de variância, sendo as médias comparadas pelo teste Scott-Knott, a 5% de significância. A segunda época (20/10/12) foi a que proporcionou maior rendimento de grãos para a maioria das cultivares nos dois municípios estudados, sendo que as seis cultivares analisadas apresentaram variação na produtividade em função da época e local de cultivo. A quarta época de semeadura (05/11/12) foi a que mais influenciou na massa de mil grãos, devido a redução no ciclo das cultivares nessa época.Palavras-chave: Glycine max (L.) Merrill; épocas semeadura; temperatura; precipitação. SOYBEAN VARIETIES BASED ON CLIMATIC ELEMENTS IN THE MUNICIPALITIES OF TANGARÁ DA SERRA E DIAMANTINO, MT ABSTRACT: The objective of this study was to evaluate the influence of temperature and precipitation in the agronomic performance of six soybean cultivars sown in four seasons in the municipalities of Tangará da Serra and Diamantino, MT. The field experiments were conducted in the 20012/13 crop season. The experimental design was a randomized block with factorial treatment 2x4x6. Being two locations, four sowing seasons (10/05/2012, 10/20/2012, 11/05/2012 and 11/20/2012) and six soybean cultivars (AS7307, ANTA 82, TMG 1179, P98Y30, TMG 132 and M-SOY 9144), totaling 48 treatments and three replications. The following evaluations were conducted: number of pods per plant, number of seeds per pod, thousand grain weight, productivity and daily sequential water balance. The results were subjected to analysis of variance and the means were compared by Scott-Knott test at 5% probability. The second sowing season (10/20/12) had the highest grain yield for most of the cultivars in both municipalities. The six cultivars analyzed had variation in productivity due to the sowing season and region of cultivation. The fourth sowing season (11/05/12) was the greatest influence in thousand grain weight, due to a reduction in the cultivars cycle in this season.Keywords: Glycine max (L.) Merrill; sowing seasons; temperature; precipitation.

High night‐temperature (HNT) stress during the reproductive stage of rice (Oryza sativa L.) reduces spikelet fertility and yield by inhibiting important physiological processes. However, specifics such as the period of time that is most sensitive to HNT, is unknown. To investigate this, we conducted four controlled‐environment experiments with two rice cultivars, N22 (HNT tolerant) and WAB56–104 (HNT susceptible). These cultivars were exposed to varying durations and intensities of night temperatures (control, 24°C; HNT, 30 and 35°C) during the reproductive stage. The effect of HNT on spikelet fertility and grain weight varied with duration: spikelet fertility reduced by 47–77% when exposed to HNT for 15 nights, 6–29% when exposed for four nights, and 9–15% when exposed for 5.5 h (pre‐midnight, 1830–0000 h or post‐midnight, 0000–0530 h) for four nights. Spikelet fertility and grain weight were most sensitive to HNT during the first 4 d of anthesis, compared with 1–4, 5–8, and 9–12 d before anthesis. At anthesis, reduction in spikelet fertility did not differ significantly between pre‐ and post‐midnight high‐temperature treatments. Our results suggest that greatest sensitivity to HNT during the reproductive stage occurs during the first 4 d of anthesis, providing a reference for future studies involving HNT tolerance in rice.

The aim of this study was to reduce the lodging and improve grain yield by evaluation the performance of some oat cultivars introduced into Iraq. A field experiment was conducted during two seasons of 2017-2018 and 2018-2019, included four cultivars (Genzania, Shafa, Carrolup and Hamel) under the influence of foliar spraying of ethephon at concentrations of 0, 500 and 1000 ppm, and foliar application of boron with concentrations of 0, 50 and 100 ppm. Using RCBD within split–split arrangement and three replicates. The results were revealed that Genzania was recorded the highest number of grains head-1 and grain yield 6.512 and 5.565 t ha-1 in the two seasons respectively. Shafa had the highest number of active tillers m-2 in both seasons and the highest single grain weight in the second season. Carrolup was produced the highest single grain weight in the first season. Spraying ethephon with concentrations of 500 and 1000 ppm increased stem diameter and number of active tillers m-2 for both seasons. Spraying 500 ppm of ethephon increased grain yield in the first season and reduced lodging rate in the second season. Ethephon with 1000 ppm reduced lodging rate in both seasons. Foliar application of boron with concentrations of 50 and 100 ppm increased plant height and grain yield in both seasons.

The present work was conducted at the ExperimentalFarm of Nubaria that located 46 km west of Alexandriaduring the two winter seasons (2015/ 2016 and2016/2017). The main objective of the present studywas to determine the effect of nitrogen fertilizer levels,biofertilizers and their interactions on growth and yieldof Shandaweel 1 (bread wheat cultivar) using split- plotdesign with four replicates. The most importantobtained results could be summarized as follows:Nitrogen fertilization at 90 kg/ fed producedthe highest number of spikes/ m2 (387.32, 402.13),number of grains/ spike (58.17, 56.49), 1000-grainweight (53.14, 54.22 g), grain yield (2.81, 2.43 t/ fed.),biological yield (9.94, 7.58 t/ fed.) and protein content(13.83, 12.85%) in the first and second seasons,respectively, and harvest index (32.05%) in the secondseason. Also, the same level of nitrogen produced thehighest LAI (6.149, 7.455) tallest plants (110.39,112.09 cm), longest spikes (11.37, 10.73 cm) and latestheading (95.08, 95.97 day) in the two successiveseasons.Biofertilizers, especially Azotein significantlyincreased all growth traits, number of grains/ spike,1000- grain weight, grain and biological yields, harvestindex and protein content in the two seasons.Biofertilizers combined with 90 kgN/ fed applicationproduced the highest LAI in the two seasons, grain andbiological yields in the first season and protein contentin the second season.

Eight cultivars of dry-land wheat (Triticum aestivum L.) historically planted in Shaanxi Province, China, were grown in plots with irrigation and drought treatments during the growing seasons of 2011–2014, so as to characterize the differences in the rate and duration of the grain-filling stage among cultivars. The experimental results showed no obvious change among cultivars with respect to the duration of the grain-filling stage and no significant correlation between duration and grain weight. The filling rates of all three phases (lag, linear, and mature periods) showed significant differences among cultivars and had a greater effect on the grain weight than the duration of the filling stage, even though drought decreased the filling rate in the linear and mature periods. A lower filling rate led to a lighter grain weight in inferior grains than in superior grains. For the superior and inferior grains in the central spikelets, modern cultivars possess faster filling rates, especially in the lag and linear periods, whereas for the whole spike, no significant trend with cultivar replacement was observed. Faster filling rates with stable filling durations will be beneficial in obtaining additional yield increases.

While global food demand is projected to grow by 50–80% by 2050, Australia is expected to continue its significant contribution to global food security. We quantified how recent climatic changes have affected wheat crops in Australia over the last 38 years. Changes in drought, heat and frost stresses affecting a mid-maturing cultivar sown on May 15 were quantified over 1981–2018 using an improved version of the Agricultural Production Systems sIMulator (APSIM). Modifications to APSIM-wheat module included the addition of two calculation subroutines for estimating direct impact of frost events and heat shocks on grain setting and grain filling. National drought-induced yield loss exceeded 40%, significantly increasing by 3.6% per decade (P 26 °C) on grain yield have significantly increased mostly due to a significant trend in the impact on individual grain weight. At the national level, frost damage has reached 14% of wheat yield and has been significantly increasing since 1981. Overall, wheat yield has decreased at a significant rate of 180 kg ha−1 per decade (P < 0.01) with the largest decreasing rate in the South-East and East. As heat and drought are expected to remain predominant yield-limiting factors in the future, adaptation of wheat germplasm to warmer and drier environments appears to be a priority to enhance grain yield in Australia.

The aim and tasks of the study. The purpose was to study the combining ability of winter bread wheat cultivars – carriers of wheat-rye translocations (WRT) for performance elements to determine their breeding values and to simulate selection of high-yielding offspring. Results and discussion. The results of analysis of variance attest to strong effects both of the general combining ability (GCA) and of the specific combining ability (SCA) for performance elements in the cultivars under investigation. At the same time, the mean square variance of the GCA was higher than that of of the SCA. Thus, we can affirm that additive effects dominate in the genetic control of the bread winter wheat performance elements, since the ratio of variances was >1.We distinguished the cultivars with a high GCA in F1for performance elements: Smuhlianka – the spikelet number in the main spike, 1000-grain weight, grain weight per plant; Epokha Odeska – the grain number in the main spike; Kryzhynka – 1000-grain weight; Rozkishna – grain weight from the main spike and grain weight per plant. Smuhlianka was distinguished among the others due to its with high and intermediate effects of the GCA. Kryzhynka, Rozkishna, and Epokha Odeska were some what inferior to it. Estimation of the combining ability suggests Smuhlianka as the best donor of grain productivity elements. According to the SCA constants, all the studied wheat cultivar shad intermediate indices for the most traits in 2014–2015. Cultivars with WRT were not distinguished by stable constants of the SCA and were not inferior tothe other studied cultivars, except Epokha Odeska. High constants of the SCA for some traits in WRT carriers indicate increased variability of the trait under investigation. Therefore, these cultivars may have specific hybrid combinations both with overexpression and with under expression of an inherited trait.Conclusions. Cultivars with wheat-rye translocations – Smuhlianka and Kryzhynka are of the highest value for breeding as components in crossings, providing formation of promising populations for selection of elite plants with increased performance.

There is a large variation in the number of days from heading to flower opening among flowers attached to a single panicle in rice (Oryza sativa L.). However, the details of order and timing of flower opening among flowers and the differences between genotypes in the variation have not been well described. In the present study, we developed a mathematical model to characterize the differences between genotypes in the relationship between the relative position of the flowers on a panicle and the number of days to their openings after heading, using three high-yielding rice cultivars, Tequing, Hokuriku 193, and Momiroman. Our model used the standardized panicle structure: each flower position was scaled based on the number of primary branches, the number of secondary branches on a primary branch, and the number of flowers on a branch. The parameters provided by the model described the variation of the number of days from heading to flower opening for each flower attached to different position on a panicle in each cultivar, so that the parameters could describe the genotypic difference in the variation. Generally, the model analyses showed that the primary branch had a greater effect on the number of days from heading to flower opening than the secondary branch within a primary branch and the position of the flowers within a secondary branch. In term of the genotypic difference among the examined cultivars, Momiroman took more 3–5 days to complete opening of all the flowers on a panicle after heading than the other cultivars. The model analyses showed that the longer duration in Momiroman was caused by the larger difference in days to flower opening among flowers on a single secondary branch and the two-days longer lag until the flowers started opening after heading. Our analyses also suggested that the genotypic difference in the number of branches did not affect the genotypic difference in duration from heading to flower opening among the cultivars examined here. We discussed the application of this model to understand genotypic differences in the relationship between the time required for flower opening and final grain weight.

This work aimed to achieve effective use of some environmental friendly treatments of bio agents (Streptomyces lydicus- Trichodermaharziunum- Trichodermaviride) on specific and technological quality of wheat. This study was carried out in the Abu Rawash province area, Giza Governorate during two successive seasons of 2014/2015 and 2015/2016.Two cultivars grain (Wheat Egypt 1, Wheat Egypt2) were used in this study. The maximum of 1000 grain fresh weight obtained in Streptomyces lydicus followed Trichodermaharziunum and Trichodermaviride in both seasons. While, the lowest value of 1000grain fresh weight were recorded in case of control application. Also, CV. Egypt 1 gave higher fresh weight/ 1000 grain weight, starch and wet- gluten high than CV. Egypt 2 in most cases in both seasons. Streptomyces lydicus treatment in wheat Egypt I recorded highest significant increased wet -gluten (33.33 and 33.60) followed by other treatments. While recorded treatment Streptomyces lydicus with Egypt 2 as compared with the control produced the lowest value with wheat Egypt 2 (27.36 and 27.13) in both seasons. Data showed that there is non-significant difference between Egypt 1 and Egypt 2 cultivars in water absorption in treatments Streptomyces lydicus, methyljasmonate and Trichodermaharziunum, while there is a significant increase in Egypt 2 compared with Egypt 1 cultivars in treatments with Trichodermaviride and control plants. Also, there is non-significant difference between Egypt 1 and Egypt 2 cultivars in arrival time and dough development time in treatments of Streptomyces lydicus, methyljasmonate, Trichodermaharziunum and control except treatment Trichodermaviride for rheological quality.

A field Experiments were carried out during two winter successive seasons 2011/2012 and 2012/2013 at Sakha Agricultural Research Station. AgriculturalResearchCenter at the north region of Delta Egypt, to illustrate the importance of studying sowing dates of some wheat cultivars. Ten cultivars of bread wheat (Sakha 93, Sakha 94, Giza 168, Misr 1, Misr 2, Gemmeiza 9, Gemmeiza 11, Sids12, Shandawel 1 and Giza 171) were sown at 20th October, 20th November and 20th December. Sowing date were separated and wheat cultivars were distributed randomly in the every experiment. The results indicated that there were significant differences among the three sowing dates for all studied traits in both seasons. Sowing on 20th October recorded the lowest days to heading and straw yield, longest time to maturity. Meanwhile, sowing on 20st November recorded the tallest plants, highest number of spikes/m2, number of grains/spike and grain yield. On the other hand, sowing on 20th December recorded the decreases in yield and increases in protein percentage. The differences among bread wheat cultivars were significant in both seasons. Misr 2 recorded the highest number of days to heading and maturity. Sakha 94 recorded the highest number of tillers/m2. Giza 171 produced the highest values for 1000- grain weight. Misr 2 and Sakha 94 recorded the highest number of grains/spike and straw yield. Meanwhile, Misr 1 and Gemmeiza 9 recorded the highest grain and straw yields/Fed. Giza 168 recorded the highest values for both of harvest index and protein percentage. Sakha 94 recorded the highest number of days to heading and maturity and plant height when sowing on 20 November. Gemmeiza 11and Giza 171 recorded the highest values for 1000- grain weight in two seasons when sowing on 20 November. It can be concluded that sowing Giza 168 and Misr 1 on different sowing dates, sowing Gimaza 9, Gemmeiza 11, Shandaweel 1 and Giza 171 on optimum date and sowing Misr 2 on the late date are recommended for optimum grain at Kafr elsheikh area.

A field trial was conducted on an acid pseudogley soil during the 2011/12, 2012/13 and 2013/14 growing seasons to evaluate grain yield and its components in four triticale cultivars ('Favorit', 'Tango', 'Odisej' and 'KG-20'). The highest values of grain yield, 1,000-grain weight, number of grains per spike, spike length and plant height in all cultivars were obtained in the year characterised by moderate temperatures during grain filling and high amounts of rainfall in the second part of the growing season. 'Favorit' gave the highest grain yield, the largest number of grains per spike, the lowest 1,000-grain weight and the smallest plant height. The highest 1,000-grain weight and the lowest number of grains per spike were found in 'Tango'. 'KG-20' had the greatest plant height and the lowest average grain yield during the three experimental years, with the lowest grain yield achieved in the driest year, and the highest in the wettest year. 'Odisej' exhibited a high grain yield, fewer grains per spike, and the lowest grain weight per spike compared to the other cultivars.

The purpose of this study was to evaluation of several local rice genotypes in the Mandailing Natal Province of North Sumatra. This studay was and has been conducted from April 2017 to October 2017. Data observed in the form of quantitative data and qualitative data of local rice plants. The results showed that rice cultivars were found in various regions in Mandailing Natal District with a high variety of characteristics. Sampling was done by purposive sampling from 23 sub-districts in Mandailing Natal District. Data observed in the form of quantitative data and qualitative data of local rice plants. The results showed that rice cultivars were found in various regions in Mandailing Natal District with a high variety of characteristics. The sigudang genotype was the best genotype with a total grain weight of 82.6 grams. Genotype Sisorang have a good agronomic appearance.

Grain filling determines the grain weight, a major component of grain yield in cereals. Grain filling in barley depends on current assimilation and culm reserves (mainly water-soluble carbohydrates). Nowadays barley is facing heat stress problem which is mostly responsible to reduce the yield of barley. A field experiment was conducted at the Field Lab, Department of Crop Botany, BangladeshAgriculturalUniversity, Mymensingh during November 2015 to March 2016 to study the grain filling patterns and the contributions of culm reserves to grain yield under heat stress. The experiment consisted of two factors—barley cultivars and heat stress. The heat stress was imposed by late sowing. The tillers were sampled once a week during grain filling period to determine the changes in dry weights of different parts, viz., leaves, culm with sheath, spikes, and grains; and to examine the contribution of culm reserves to grain yield. The results in the experiment revealed that the grain yield was reduced by 22-28% due to the stress. The grain yield varied from 52 to 150 g m−2 with the mean of 102 g m−2 under control while it varied from 37 to 116 g m−2 with the mean of 75 g m−2 under heat stress. Among the cultivars studied BARI Barley5, BARI Barley2 and BARI Barley1, seemed as high yielders while BARI Barley3, BARI Barley4, BARI Barley6 as the low yielders under heat stress treatment. The reduction in grain yield was attributable mainly to lighter grain weight due to the stress. Heat stress drastically reduced the grain filling duration by 45–50%. However, the stress increased the grain filling rate by 6–53%. The amount of reserves remobilized to grain varied among the cultivars ranging from 4.8 to 12.77 mg spike−1 in control and from 1.73 to 6.25 mg spike−1 in stressed plants. The stressed barley plants exhibited lower accumulation of reserves in culm but they showed almost its complete remobilization to the grain. The contribution of culm reserves to grain yield varied from 1.13 to 19.52%, and 1.09 to 2.11% in control and in stressed plants, respectively. In conclusion, culm reserve is the important attributes in grain yield in Bangladeshi barley cultivars but the contribution remains almost unaffected due the post-anthesis heat stress.J. Bangladesh Agril. Univ. 15(2): 174-181, December 2017

La densidad de población es uno de los principales factores que contribuyen a incrementar el rendimiento de grano en maíz. El presente trabajo se estableció en 2013 en tres localidades del centro del Estado de México, México para evaluar el rendimiento de grano y sus componentes principales en diez cultivares de maíz en tres densidades de población. Los tres ensayos se establecieron en campo en un diseño experimental de bloques completos al azar con tres repeticiones en un arreglo de parcelas divididas: en las parcelas grandes se distribuyeron las densidades de población y en las chicas los cultivares. Hubo diferencias significativas (p = 0.01) entre cultivares en las 13 variables registradas, en densidad de población éstas lo fueron en longitud de mazorca, diámetro de mazorca, peso de olote, peso de grano por planta, y rendimiento de grano. Un incremento en la densidad de población disminuyó el número y el peso de grano por planta pero a 104 167 plantas ha-1 el rendimiento fue de10.03 t ha-1. Con P204W se obtuvo la mayor producción de grano (10 t ha-1), pero éste no difirió estadísticamente de IC 2010, AS-MJ9082, H-40 y AS-723. El análisis de componentes principales explicó 65.94% de la variación total original, en éste se observó una alta correlación entre rendimiento de grano, granos por planta, índice de prolificidad y peso de olote.

Improvement of grain yield (GY) at farm level, which is closely related to GY potential, seems to be the main alternative to increase wheat (Triticum aestivum L) production. The aim of current research was to assess the genetic progress of GY potential and associated physiological traits as well as the GY stability under diverse environments of cultivars released to the Argentine market during the last five decades (1971–2011). Ten cultivars, classified into two groups of five according to the time to anthesis in late cycle (LC) and early cycle cultivars (EC), were grown under twelve environments (E1 to E12) in Pergamino, Argentina. The environmental index of GY (average of cultivar’s GY in each environment) ranged from 174 to 602 g m−2. Under potential conditions (E1 to E3, 602 to 548 g m−2), GY improved at 0.74 % per year of release (YOR) (or 4.20 g m−2 per YOR) across all cultivars. The harvest index (HI), particularly in LC, and total biomass produced at physiological maturity (BTPM), associated with crop growth rate during stem elongation (CGRSE) and total biomass produced at anthesis (BTA), particularly in EC, were improved by breeding explaining the GY potential increase. Maximum HI reached 0.46, suggesting it can be further improved in both groups, but pre-anthesis growth should continue increasing in EC, as it seemed to be a yield-limiting trait for these cultivars. Grain number per m−2 (GN) increased by recent breeding in both groups with no change in grain weight (GW). This was a consequence of greater grain number per spike (GNS) in EC, as expected, but higher spike number per m−2 (SN) in LC. Fruiting efficiency (FE, grains g−1 of spike dry weight at anthesis -SDWA-), rather than SDWA, seems to have been improved by recent breeding, turning it a key trait to further increase GN. Finally, modern cultivars out-yielded the old ones in a wide range of environments, suggesting that wide adaptation is a valid breeding strategy for Argentine conditions.