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The aim of the study was to examine the impact of microbiological and organic fertilizers on morphological and productive characteristics of triticale during a three-year period (2009/10–2011/12). A two-factorial field experiment was arranged using a randomized block design with four replications. The object of the study was the triticale winter cultivar Odisej, and the following treatments were applied: a control variant without fertilization, microbiological fertilizer “Slavol” (Agrounik Serbia) 5.0 l ha-1, organic fertilizer “Biohumus Royal offert” (Altamed RS) 3.0 t ha-1 + microbiological fertilizer “Slavol” (Agrounik Serbia) 5.0 l ha-1. The results showed that the expression of the characteristics was significantly affected by the environment. The lowest values were obtained in the first year when the most unfavourable meteorological conditions were observed. The application of microbiological fertilizer had no impact on the stem length and grain weight per spike, but it significantly increased the number of fertile spikelets (3.7%), spike length (7.7%) and grain yield (18.6%). The combined application of fertilizers provided better results for all the examined characteristics, while in comparison with the control, the differences ranged from 4.3% for the number of fertile spikelets to 46.5% for grain yield. The strongest correlation was determined between the spike length and the number of fertile spikelets (r = 0.939**). The obtained results lead to the conclusion that under variable environmental conditions, the application of fertilizers has a significant impact on morphological and productive characteristics of triticale, and consequently on the stability of this crop production in the organic farming system. Cilj istraživanja bio je ispitivanje uticaja biohumusa i biofertilizatora na morfološke i produktivne osobine tritikalea u trogodišnjem periodu (2009/102011/12). Poljski ogled je postavljen kao dvofaktorijalni, po metodi blok sistema sa slučajnim rasporedom tretmana u četiri ponavljanja. Predmet ispitivanja bila je ozima sorta tritikalea, Odisej, a ispitivan je uticaj sledećih tretmana: kontrola bez đubrenja, biofertilizator (5,0 l ha-1), biohumus (3,0 t ha-1) + biofertilizator (5,0 l ha-1). Rezultati su pokazali da spoljašnja sredina ima značajan uticaj na ekspresiju ispitivanih osobina. Najmanje vrednosti dobijene su u prvoj godini, koja je imala i najnepovoljnije meteorološke uslove. Đubrenje je imalo statistički značajan uticaj na većinu ispitivanih osobina. Primena biofertilizatora nije uticala na dužinu stabla i masu zrna u klasu, ali je značajno povećala broj plodnih klasića (3,7%), dužinu klasa (7,7%) i prinos zrna (18,6%). Kombinovanom primenom đubriva postignuti su bolji rezultati za sve ispitivane osobine, a razlike u odnosu na kontrolu bez đubrenja kretale su se u nivou od 4,3% za broj plodnih klasića do 46,5% kod prinosa zrna. Najjača korelaciona povezanost ustanovljena je između dužine klasa i broja plodnih klasića (r = 0,939**). Dobijeni rezultati upućuju na zaključak da, u promenljivim uslovima spoljašnje sredine, primena dobro izbalansiranih formula organskih i mikrobioloških đubriva ima značajan uticaj na morfološke i produktivne osobine tritikalea, a samim tim na stabilnost proizvodnje ovog useva u sistemu organskog gajenja.

Grain size and flag leaf angle are two important traits that determining grain yield in rice. However, the mechanisms regulating these two traits remain largely unknown. In this study, a rice long grain 5 (lg5) mutant with a large flag leaf angle was identified, and map-based cloning revealed that a single base substitution followed by a 2 bp insertion in the LOC_Os05g40384 gene resulted in larger grains, a larger flag leaf angle, and higher plant height than the wild type. Sequence analysis revealed that lg5 is a novel allele of elongated uppermost internode-1 (EUI1), which encodes a cytochrome P450 protein. Functional complementation and overexpression tests showed that LG5 can rescue the bigger grain size and larger flag leaf angle in the Xiushui11 (XS) background. Knockdown of the LG5 transcription level by RNA interference resulted in elevated grain size and flag leaf angle in the Nipponbare (NIP) background. Morphological and cellular analyses suggested that LG5 regulated grain size and flag leaf angle by promoting cell expansion and cell proliferation. Our results provided new insight into the functions of EUI1 in rice, especially in regulating grain size and flag leaf angle, indicating a potential target for the improvement of rice breeding.

Fusarium graminearum and Zymoseptoria tritici cause economically important diseases of wheat. F. graminearum is one of the primary causal agents of Fusarium head blight (FHB) and Z. tritici is the causal agent of Septoria tritici blotch (STB). Alternative control methods are required in the face of fungicide resistance and EU legislation which seek to cut pesticide use by 2030. Both fungal pathogens have been described as either hemibiotrophs or necrotrophs. A microbial fermentation-based product (MFP) was previously demonstrated to control the biotrophic pathogen powdery mildew, on wheat. Here we investigated if MFP would be effective against the non-biotrophic fungal pathogens of wheat, F. graminearum and Z. tritici. We assessed the impact of MFP on fungal growth, disease control and also evaluated the individual constituent parts of MFP. Antifungal activity towards both pathogens was found in vitro but MFP only significantly decreased disease symptoms of FHB in planta. In addition, MFP was found to improve the grain number and weight, of uninfected and F. graminearum infected wheat heads.

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.

Around the world, salinity a critical limiting factor in agricultural productivity. Plant growth is affected by salt stress at all stages of development. The contemporary investigation focused on Chaetomorpha antennina aqueous extracts (SWEs) to decrease the effects of salt strain on rice germination, growth, yield, and the production of key biological and biochemical characters of the rice, Oryza sativa L. (Poaceae). SWE improved the germination capacities of rice seedlings by promoting their emergence 36.27 h prior to those that had been exposed to saline stress. The creation of 79.647% longer radicles by SWE treatment on salt-stressed seeds which boosted the establishment effectiveness of seeds produced under salt stress longer radicles resulted in plants that were 64.8% taller. SWE treatment was effective in revoking the levels of protein (26.9%), phenol (35.54%), and SOD (41.3%) enzyme levels that were previously constrained by salinity stress. Additionally, SWE were also efficient in retaining 82.6% of leaf water content and enhancing the production of photosynthetic pigments affected by salt exposure earlier. The improvement in plant functionality was evident from the display of increase in tiller numbers/hill (62.36%), grain yield (58.278%), and weight (56.502%). The outcome of our research shows that SWEs protected the plants from the debarring effects of salinity by enhancing the plant functionality and yield by mechanistically enriching their physiological (germination and vegetative growth) and biochemical attributes (leaf RWC, photosynthetic pigments, protein, phenol, and SOD). Despite the increase in TSS and starch levels in rice grain exposed to salinity stress, SWE improved the grain protein content thus cumulatively enhancing rice nutrition and marketability. The current investigation reveals that the extracts of C. antennina can help alleviate rice plants from salt stress in an efficient, eco-friendly, as well as economical way.

Identifying traits for improving sink-strength is a bottleneck to increasing wheat yield. The interacting processes determining sink-strength and yield potential are reviewed and visualized in a set of 'Wiring Diagrams', covering critical phases of development (and summarizing known underlying genetics). Using this framework, we reviewed and assembled the main traits determining sink-strength and identified research gaps and potential hypotheses to be tested for achieving gains in sink-strength. In pre-anthesis grain number could be increased through: (i) enhanced spike growth associated with optimized floret development and/or a reduction in specific stem-internode lengths and (ii) improved fruiting efficiency through accelerated rate of floret development, improved partitioning between spike or optimized spike cytokinin levels. In post-anthesis grain sink-strength could be augmented through manipulation of grain size potential via ovary size and/or endosperm cell division and expansion. Prospects for improving spike vascular architecture to support all rapidly growing florets, enabling the improved flow of assimilate, are also discussed. Finally, we considered the prospects for enhancing grain weight realization in relation to genetic variation in stay-green traits as well as stem carbohydrate remobilization. The Wiring Diagrams provide a potential workspace for breeders and crop scientists to achieve yield gains in wheat and other field crops. Research of the authors on physiology and genetics of wheat yield potential has been funded by many different sources over the years. Most recent grants include the International Wheat Yield Partnership (IWYP) projects funded by the Biotechnology and Biological Research Council of the UK (e.g., IWYP48 BB/N021061/1, IWYP64 BB/ N020871/2, IWYP163 BB/S005072/1, and IWYP25FP), as well as projects funded by other donors (State Research Agency of Spain: AGL2015-69595-R and RTI2018-096213-B-100).

Emmer wheat (Triticum turgidum ssp. dicoccum) is one of the most promising gene sources for drought tolerance improvement of durum wheat (Triticum turgidum ssp. durum). Achieving desired results requires a conscious choice of crossing parents based on general and specific combining ability (GCA and SCA) and also understanding the genes action involved in controlling the desired traits. In this study a 12 × 12 full diallel cross was performed using four emmer and eight durum wheats. The 132 hybrid progenies along with their parental lines were field evaluated under water-stressed and non-stressed conditions. Based on the Griffing diallel analysis both GCA and SCA effects were highly significant for all measured traits under both water treatments indicating possibility of improvement for drought tolerance. In this respect, the amount of additive effect was higher than the non-additive suggesting the chance for genetic advancement through selection. Based on Hayman's graphical analyses under the two water conditions it was revealed that several grain yield component traits were under the control of partial dominance. In contrary, grain yield and most morphological traits showed either dominance or over-dominance gene action. Grain yield had a significant positive correlation with the number of kernels per spike, kernel diameter, grain weight per spike and harvest index. These traits also had greater share of additive effects, relatively high narrow-sense heritability and high Baker ratio suggesting effective indirect selection for grain yield. Most durum × emmer hybrids had grain yield and drought tolerance indices better than the parents indicating that Iranian emmer wheats have a great genetic potential for drought tolerance improvement of durum wheat.

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.

An experiment was carried out at Agricultural Research Station, Vaigaidam, Theni district of Tamil Nadu from 2007 to 2019 with an objective of developing a variety by deriving the grain quality characters from the traditional rice variety Seeragasamba and yield and yield attributing characters from ADT 43. The promising culture VG 09006, a cross derivative of ADT43/Seeragasamba was released as VGD 1 during 2019 by the State Variety Release Committee, Tamil Nadu. It is a medium duration variety (129 days) with erect, high tillering and non lodging plant habit. This variety is recommended for samba/late samba seasons of Dindigul, Theni, Trichy, Perambalur, Karur, Coimbatore, Erode, Dharmapuri, Vellore and Virudhunagar districts of Tamil Nadu. It recorded an overall mean grain yield of 5859 kg/ha at 101 locations, which was 32.56 and 13.80 per cent increased grain yield over Seeragasamba (4420 kg/ha) and TKM 13 (5149 kg/ha), respectively. It is moderately resistant to leaf folder, blast and brown spot under field conditions. The rice is white, fine (short slender) with a 1000 grain weight of 8.9 g which is less than Seeragasamba (11.6 g) and all other popularly grown rice varieties viz., TKM13 (13.8 g, CO 51 (16.0 g) and ADT 43 (15.5 g). Key wordsBriyani rice, Quality rice, Seeragasamba, aromatic rice, VGD 1

Rice grain yield is determined by three major “visible” morphological traits: grain weight, grain number per panicle, and effective tiller number, which are affected by a series of “invisible” physiological factors including nutrient use efficiency and photosynthetic efficiency. In the past few decades, substantial progress has been made on elucidating the molecular mechanisms underlying grain yield formation, laying a solid foundation for improving rice yield by molecular breeding. This review outlines our current understanding of the three morphological yield-determining components and summarizes major progress in decoding physiological traits such as nutrient use efficiency and photosynthetic efficiency. It also discusses the integration of current knowledge about yield formation and crop improvement strategies including genome editing with conventional and molecular breeding.

General combining ability (GCA) has been successfully used to evaluate the parental performance in hybrid breeding program, while the molecular basis of GCA still remains unknown. In this study, RNA-Seq was employed to compare the transcriptome profiles that determined the GCA for yield-related traits in two different barley genotypes. A total of 1051 differentially expressed unigenes (DEGs) including 599 up-regulated DEGs and 452 down-regulated DEGs were found between Baodamai 12 and Ximala 22. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analysis revealed that many DEGs participated in metabolic process, stimulus response, catalytic activity and biosynthesis. Furthermore, 11 DEGs involved in the starch and sucrose metabolism pathway were discovered, among which eight up-regulated genes were related to beta-fructofuranosidase, pectinesterase, beta-glucosidase and hexokinase, while the other three down-regulated genes were related to sucrose-phosphate synthase, beta-glucosidase and hexokinase. These DEGs might contribute to the differences of GCA for grain weight between the two genotypes. The results may provide a new insight in the studying of the molecular basis of GCA and establish a foundation for further genomic research on the improvement of combining ability in barley breeding program.

The TaGS3 homoeologous genes (homoeologs) located on chromosomes 7A, 4A, and 7D in hexaploid wheat were cloned. Relative expression analysis of the three TaGS3 homoeologs revealed that the expression levels of TaGS3-4A and TaGS3-7D in developing grains were higher than that of TaGS3-7A. Genetic evidence showed that TaGS3 was a negative regulator of grain weight and grain size. Fifteen polymorphic sites and five haplotypes were detected in TaGS3-4A. Two molecular markers were developed to distinguish the five haplotypes. Association analysis using 260 accessions from Chinese wheat mini-core collection (MCC) indicated that TaGS3-4A affected thousand grain weight (TGW) and grain length (GL). HAP-4A-1 and HAP-4A-2 were favorable haplotypes that increased TGW and GL and had undergone strong selection during domestication of wheat. In addition, interaction of the TaGS3-4A and TaGS3-7D homoeologs had significant additive effects on the grain traits. Hap-4A-1/Hap-7D-2 was the best haplotype combination in increasing TGW and GL. The frequencies and geographic distributions of favorable TaGS3 haplotypes among 1388 wheat accessions from worldwide sources provided clues for selection of yield-related traits. Our findings demonstrated that TaGS3-4A had significant effects on TGW and GL. Marker-assisted selection of HAP-4A-1/2 combined with HAP-7D-2 has potential to increase wheat yields.

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).

Societal Impact Statement Micronutrients such as zinc and iron are critical for human health. For the world's population that relies on cereal products to obtain micronutrients, the bioavailability (absorption of nutrients in the gut) can be hindered by an anti‐nutritional compound, phytate. Phytate accumulation in grain is affected by soil properties including phosphorus availability and arbuscular mycorrhizal (AM) fungi. Here, we investigated the effects of AM fungi and soil phosphorus fertilization on micronutrient bioavailability in durum wheat and found that fertilization greatly decreased the bioavailability of micronutrients, but AM fungi can take up more micronutrients, which can lead to improved bioavailability when the soil is not fertilized. Summary The bioavailability of micronutrients (zinc [Zn] and iron [Fe]) in cereal crops such as durum wheat is critically important for human nutrition. Bioavailability is a product of complex interactions between plant phosphorus (P) uptake and storage in grain (as phytate), and plant micronutrient uptake. The bioavailability of Zn and Fe in cereal grain is affected by soil nutrient concentrations and associations with arbuscular mycorrhizal (AM) fungi, but has been scarcely studied. A geographically diverse collection of 101 durum wheat genotypes was surveyed for grain bioavailability of Zn and Fe. Ten genotypes were then selected and grown with and without AM fungal inoculation and soil P fertilization to understand the effects of manipulating soil P availability and uptake on micronutrient bioavailability. The strongest negative effect on grain micronutrient bioavailability was soil P fertilization, however, it also led to increased grain weight. Crop variety selection had the greatest variation in the P‐fertilized soil, but AM fungal inoculation had a positive effect on bioavailability in one variety in the non‐fertilized soil. In order to grow more nutritious durum wheat crops, variety selection and AM fungal inoculation are important considerations. In general, there is a trade‐off between grain weight (yield) and micronutrient bioavailability in grain that could be addressed through breeding P‐deficiency tolerant varieties.

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.

Malting quality will be greatly deteriorated when barley plants suffer from post-anthesis drought stress, however there is a marked difference among barley genotypes in the responses of malting quality to drought stress, and the molecular mechanisms underlying the genotypic difference remain unclear. We made transcriptome and metabolome analysis on the developing grains of two barley genotypes differing in the responses to drought stress. Post-anthesis drought treatments led to decreased grain weight and β-glucan content, increased grain protein content and β-amylase activity. Drought stress enhanced H2O2 and heat-shock protein accumulation in the two barley genotypes, with the drought-tolerant genotype showing higher capacity of scavenging H2O2 and reducing misfolded protein accumulation than the drought-susceptible genotype. Moreover, the drought-tolerant genotype was more efficient in redistributing assimilates stored in the vegetative tissues into the developing grains. After re-watering to relieve drought stress, the drought-tolerant genotype can further modify auxin transport and ethylene signaling, enhancing redistribution of assimilates into grains. Transcriptome comparisons and weighted correlation network analysis (WGCNA) identified some key genes regulating the responses of malting quality traits to drought stress, such as RLK-LRR, β-glucosidase and HSP . In conclusion, less change of main malting quality traits in the drought-tolerant genotype under post-anthesis drought stress is attributed to its higher capacity of alleviating the stress injury through scavenging ROS and redistributing the metabolites stored in the vegetative organs into the developing grains.

Length of grain affects the appearance, quality, and yield of rice. A rice long-grain chromosome segment substitution line Z744, with Nipponbare as the recipient parent and Xihui 18 as the donor parent, was identified. Z744 contains a total of six substitution segments distributed on chromosomes (Chrs.) 1, 2, 6, 7, and 12, with an average substitution length of 2.72 Mb. The grain length, ratio of length to width, and 1 000-grain weight of Z744 were significantly higher than those in Nipponbare. The plant height, panicle number, and seed-set ratio in Z744 were significantly lower than those in Nipponbare, but they were still 78.7 cm, 13.5 per plant, and 86.49%, respectively. Furthermore, eight QTLs of different traits were identified in the secondary F2 population, constructed by Nipponbare and Z744 hybridization. The grain weight of Z744 was controlled by two synergistic QTLs (qGWT1 and qGWT7) and two subtractive QTLs (qGWT2 and qGWT6), respectively. The increase in the grain weight of Z744 was caused mainly by the increase in grain length. Two QTLs were detected, qGL1 and qGL7-3, which accounted for 25.54 and 15.58% of phenotypic variation, respectively. A Chi-square test showed that the long-grain number and the short-grain number were in accordance with the 3:1 separation ratio, which indicates that the long grain is dominant over the short-grain and Z744 was controlled mainly by the principal effect qGL1. These results offered a good basis for further fine mapping of qGL1 and further dissection of other QTLs into single-segment substitution lines.

Small Peruvian coffee producers face low yields per hectare, caused mainly by recent rust outbreaks and by natural crossing of coffee varieties, which are sown without specific order. Coffee rust has drastically reduced areas of susceptible but high-quality cup varieties as caturra, pache, and nacional, which have been replaced by others with high grain weight, but low-quality cup. This study aimed to determine the rooting capacity of sprouts subjected to different concentrations of indole-3-butyric acid (AIB) in three varieties of Coffea arabica, in the San Martin region, Peru. The most appropriate sprout rooting characteristics allowing to propagate rust-tolerant C. arabica plants were evaluated, under the effect of four doses of AIB (0, 1000, 2000, and 3000 ppm) in three coffee varieties (caturra, pache, and nacional), using microtunnels as rooting environments. A completely randomized design, consisting of three repetitions per treatment and six sprouts per repetition, was used. At the end of 50 days, the best rooting result (89%) was obtained with a dose of 2000 ppm of AIB in the caturra variety. The overall results are successful, since there is a conversion rate of sprouts into useful seedlings of more than 85%, if proper handling conditions are implemented. This method of propagation of rust-tolerant C. arabica sprouts by microtunnels enables a mass production of seedlings. The validation of these results could lead to the establishment of entire rust-tolerant coffee farms.

We used mutant cipk17 and Nipponbare in field experiments to analyze agronomic traits, photosynthetic parameters, transcriptome, and gene expression. The results demonstrated cytoplasmic localization of OsCIPK17, while GUS allogeneic (A. thaliana) tissue-staining and quantitative analysis showed the gene was expressed in many organs, including flower buds; furthermore, it was involved in root, stem, and leaf growth. Compared to Nipponbare plants, grain filling rate and final grain weight decreased in plants of the knockout mutant owing to a delay in attainment of maximum grain filling rate. Photosystem II (PSII) efficiency was also reduced. Enrichment analysis showed that the functions of differentially expressed genes (DEGs) focused on nucleoside-, nucleotide-, and lipid-binding, as well as hydrolase, transferase, and phosphorylase activities. Signaling pathways mainly included starch and sucrose metabolism, as well as photosynthesis. Additionally, some DEGs were verified by fluorescence analysis. The results showed that knockout of OsCIPK17 affected photosynthesis and starch-, sucrose-, and amino acid metabolism-related gene expression; furthermore, the mutation reduced PSII utilization efficiency, it blocked the synthesis and metabolism of starch and sucrose, and affected the formation and transport of assimilates, thereby reducing final grain weight.

Seventeen genotypes of wheat were used in this study the results showed significant differences in respect of yield and other yield contributing characters. Highest phenotypic and genotypic coefficients of variations were observed in plant height and lowest values were observed in spike length in both cases.Heritability estimated was found to be high in case of grain yield/plant and this was followed by 100 grain weight. Significant positive correlation was found in plant height with number of fertile tillers/plant and grain yield/plant, fertile tillers/plant with spike length, spike length with grain yield and grain yield with 100 grain weight. Negative correlation was found in plant height with 100 grain weight. Plant height, fertile tillers/plant, spike length and 100 grain weight appeared to be the effective criteria for improvement of yield of wheat. J. bio-sci. 28: 81-86, 2020

Low zinc (Zn) availability in various agricultural soils including Vertisols adversely affects wheat production. The variations among the wheat genotypes to produce high grain yield and Zn uptake under low Zn supply were investigated to find out the Zn-efficient genotypes. Twenty-five different wheat genotypes were evaluated in the field with two levels of Zn, viz., low (no Zn fertilizer) and high (20 kg of Zn ha−1 applied as Zn sulfate heptahydrate (ZnSO4.7H2O) (21% Zn)) along with three foliar applications of Zn at ear initiation, flowering, and milking stage of wheat growth. Thousand grain weight, grain yield, grain Zn concentration, and Zn uptake of wheat genotypes differed significantly and increased due to Zn application. Among the genotypes, grain yield efficiency index (i.e., relative grain yield) varied from 85.0 to 98.6 and Zn uptake efficiency (i.e., relative grain Zn uptake) varied from 60.9 to 88.5. Considering grain yield efficiency index and Zn uptake efficiency index, the genotypes were categorized as efficient and responsive (JW-3211, GW-322, PBW-502, HD-2864, UP-2554, HI-8627, GW-190, SUJATHA-HI-627), efficient and non-responsive (HD-2932, LOK-1, PBW-175), inefficient and responsive (HD-4672, GW-366, UP-2628), and inefficient and non-responsive (HW-2004, WH-147, HI-1418, DL-803-3, PBW-343, HD-2733, UP-2565, JW-17, C-306, AKW-4627, HI-1500). The efficient and responsive genotypes are the most useful ones as they provide higher yield under low Zn supply and also respond to Zn fertilizer application. The inefficient and responsive genotypes may be utilized by the plant breeders to identify the responsive traits for their incorporation in modifying the efficient and non-responsive genotypes.

Grain weight and grain number, the two important yield traits, are mainly determined by grain size and panicle architecture in rice. Herein, we report the identification and functional analysis of OsSPL4 in panicle and grain development of rice. Using CRISPR/Cas9 system, two elite alleles of OsSPL4 were obtained, which exhibited an increasing number of grains per panicle and grain size, resulting in increase of rice yield. Cytological analysis showed that OsSPL4 could regulate spikelet development by promoting cell division. The results of RNA-seq and qRT-PCR validations also demonstrated that several MADS-box and cell-cycle genes were up-regulated in the mutation lines. Co-expression network revealed that many yield-related genes were involved in the regulation network of OsSPL4. In addition, OsSPL4 could be cleaved by the osa-miR156 in vivo, and the OsmiR156-OsSPL4 module might regulate the grain size in rice. Further analysis indicated that the large-grain allele of OsSPL4 in indica rice might introgress from aus varieties under artificial selection. Taken together, our findings suggested that OsSPL4 could be as a key regulator of grain size by acting on cell division control and provided a strategy for panicle architecture and grain size modification for yield improvement in rice.

Background Mean grain weight (MGW) is among the most frequently measured parameters in wheat breeding and physiology. Although in the recent decades, various wheat grain analyses (e.g. counting, and determining the size, color, or shape features) have been facilitated, thanks to the automated image processing systems, MGW estimations have been limited to using few number of image-derived indices; i.e. mainly the linear or power models developed based on the projected area (Area). Following a preliminary observation which indicated the potential of grain width in improving the predictions, the present study was conducted to explore more efficient indices for increasing the precision of image-based MGW estimations. For this purpose, an image archive of the grains was processed, which were harvested from a 2-year field experiment carried out with 3 replicates under two irrigation conditions and included 15 cultivar mixture treatments (so the archive was consisted of 180 images including more than 72,000 grains). Results It was observed that among the more than 30 evaluated indices of grain size and shape, indicators of grain width (i.e. Minor & MinFeret) along with 8 other empirical indices had a higher correlation with MGW, compared with Area. The most precise MGW predictions were obtained using the Area × Circularity, Perimeter × Circularity, and Area/Perimeter indices. Furthermore, it was found that (i) grain width and the Area/Perimeter ratio were the common factors in the structure of the superior predictive indices; and (ii) the superior indices had the highest correlation with grain width, rather than with their mathematical components. Moreover, comparative efficiency of the superior indices almost remained stable across the 4 environmental conditions. Eventually, using the selected indices, ten simple linear models were developed and validated for MGW prediction, which indicated a relatively higher precision than the current Area-based models. The considerable effect of enhancing image resolution on the precision of the models has been also evidenced. Conclusions It is expected that the findings of the present study, along with the simple predictive linear models developed and validated using new image-derived indices, could improve the precision of the image-based MGW estimations, and consequently facilitate wheat breeding and physiological assessments.

Agropyron cristatum (L.) Gaertn. (2n = 4x = 28, PPPP), one of the most important wild relatives of wheat, harbors many desirable genes for wheat genetic improvement. Development of wheat-A. cristatum translocation lines with superior agronomic traits facilitates wheat genetic improvement. In this study, 5106-DS was identified to be a wheat-A. cristatum 6P (6D) disomic substitution line using cytogenetic identification and molecular markers analysis, which displayed higher thousand-grain weight than its wheat parent Triticum aestivum cv. Fukuhokomugi (2n = 6x = 42, AABBDD). Analysis of its backcross populations indicated that there might be genes conferring increased grain weight and width on the chromosome 6P of 5106-DS. In the backcross population, we found three plants as Robertsonian translocation lines, created by chromosome centric breakage-fusion. Among them, there are one T6DS·6PL and two T6PS·6DL Robertsonian translocation lines. Additionally, the centromeres of these three translocation lines were determined to be fused centromeres of 6D and 6P using the probes pAcCR1 and pCCS1. The development of Robertsonian translocation lines would promote the utilization of A. cristatum chromosome 6P in wheat improvement. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11032-021-01251-y.

Grain size, shape and weight are important factors influencing grain yield and quality of rice. They are mostly determined by grain length (GL) and grain width (GW). A 13.2 Mb interval, RM167–RM287 on chromosome 11 of rice, was previously found to be associated with variations in 1000-grain weight (TGW). In this study, three populations derived from the indica rice cross Teqing/IRBB52 were used to identify and validate quantitative trait loci (QTLs) controlling GL, GW, TGW and the ratio of GL to GW (RLW) in the RM167–RM287 region. First, two QTL clusters associated with these traits were detected using two populations, segregating the RM167–RM287 interval only. One controlled GL, GW and TGW and was designated as qGS11. The other controlled GL and RLW. The allelic directions of the two QTL clusters on GL were opposite. Then, qGS11 was further mapped in a 1.4 Mb interval using near-isogenic lines, showing a small effect on GL and a relatively large effect on TGW, GW and RLW. Meanwhile, a stable and small effect on the heading date was detected. The allelic direction for the heading date was the opposite for TGW and GW but the same for GL and RLW. The results suggest that qGS11 has the potential for application in rice breeding.

Summary Increasing grain yield has always been the primary goal of crop breeding. KLUH/CYP78A5 has been shown to affect seed size in several plant species, but the relevant molecular mechanism is still unclear and there are no reports of this gene contributing to yield. Here, we demonstrate that modified expression of TaCYP78A5 can enhance wheat grain weight and grain yield per plant by accumulating auxin. TaCYP78A5 is highly expressed in maternal tissues, including ovary and seed coat during wheat development. The constitutive overexpression of TaCYP78A5 leads to significantly increased seed size and weight but not grain yield per plant due to the strengthening of apical dominance. However, localized overexpression of TaCYP78A5 in maternal integument enhances grain weight and grain yield per plant by 4.3%–18.8% and 9.6%–14.7%, respectively, in field trials. Transcriptome and hormone metabolome analyses reveal that TaCYP78A5 participates in auxin synthesis pathway and promotes auxin accumulation and cell wall remodelling in ovary. Phenotype investigation and cytological observation show that localized overexpression of TaCYP78A5 in ovary results in delayed flowering and prolonged proliferation of maternal integument cells, which promote grain enlargement. Moreover, naturally occurring variations in the promoter of TaCYP78A5‐2A contribute to thousand‐grain weight (TGW) and grain yield per plant of wheat;TaCYP78A5‐2A haplotype Ap‐HapII with higher activity is favourable for improving grain weight and grain yield per plant and has been positively selected in wheat breeding. Then, a functional marker of TaCYP78A5 haplotype Ap‐HapII is developed for marker‐assisted selection in wheat grain and yield improvement.

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.

Grain weight is one of the major factors determining single plant yield production of rice and other cereal crops. Research has begun to reveal the regulatory mechanisms underlying grain weight as well as grain size, highlighting the importance of this research for plant molecular biology. The developmental trait of grain weight is affected by multiple molecular and genetic aspects that lead to dynamic changes in cell division, expansion and differentiation. Additionally, several important biological pathways contribute to grain weight, such as ubiquitination, phytohormones, G-proteins, photosynthesis, epigenetic modifications and microRNAs. Our review integrates early and more recent findings, and provides future perspectives for how a more complete understanding of grain weight can optimize strategies for improving yield production. It is surprising that the acquired wealth of knowledge has not revealed more insights into the underlying molecular mechanisms. To accelerating molecular breeding of rice and other cereals is becoming an emergent and critical task for agronomists. Lastly, we highlighted the importance of leveraging gene editing technologies as well as structural studies for future rice breeding applications.

Rice grain yield consists of several key components, including tiller number, grain number per panicle (GNP), and grain weight. Among them, GNP is mainly determined by panicle branches and spikelet formation. In this study, we identified a gene affecting GNP and grain yield, OsSPL9, which encodes SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE (SPL) family proteins. The mutation of OsSPL9 significantly reduced secondary branches and GNP. OsSPL9 was highly expressed in the early developing young panicles, consistent with its function of regulating panicle development. By combining expression analysis and dual-luciferase assays, we further confirmed that OsSPL9 directly activates the expression of RCN1 (rice TERMINAL FLOWER 1/CENTRORADIALIS homolog) in the early developing young panicle to regulate the panicle branches and GNP. Haplotype analysis showed that Hap3 and Hap4 of OsSPL9 might be favorable haplotypes contributing to high GNP in rice. These results provide new insights on high grain number breeding in rice.

Plant height is significantly correlated with grain traits, which is a component of wheat yield. The purpose of this study is to investigate the main quantitative trait loci (QTLs) that control plant height and grain-related traits in multiple environments. In this study, we constructed a high-density genetic linkage map using the Wheat50K SNP Array to map QTLs for these traits in 198 recombinant inbred lines (RILs). The two ends of the chromosome were identified as recombination-rich areas in all chromosomes except chromosome 1B. Both the genetic map and the physical map showed a significant correlation, with a correlation coefficient between 0.63 and 0.99. However, there was almost no recombination between 1RS and 1BS. In terms of plant height, 1RS contributed to the reduction of plant height by 3.43 cm. In terms of grain length, 1RS contributed to the elongation of grain by 0.11 mm. A total of 43 QTLs were identified, including eight QTLs for plant height (PH), 11 QTLs for thousand grain weight (TGW), 15 QTLs for grain length (GL), and nine QTLs for grain width (GW), which explained 1.36–33.08% of the phenotypic variation. Seven were environment-stable QTLs, including two loci (Qph.nwafu-4B and Qph.nwafu-4D) that determined plant height. The explanation rates of phenotypic variation were 7.39–12.26% and 20.11–27.08%, respectively. One QTL, Qtgw.nwafu-4B, which influenced TGW, showed an explanation rate of 3.43–6.85% for phenotypic variation. Two co-segregating KASP markers were developed, and the physical locations corresponding to KASP_AX-109316968 and KASP_AX-109519968 were 25.888344 MB and 25.847691 MB, respectively. Qph.nwafu-4B, controlling plant height, and Qtgw.nwafu-4B, controlling TGW, had an obvious linkage relationship, with a distance of 7–8 cM. Breeding is based on molecular markers that control plant height and thousand-grain weight by selecting strains with low plant height and large grain weight. Another QTL, Qgw.nwafu-4D, which determined grain width, had an explanation rate of 3.43–6.85%. Three loci that affected grain length were Qgl.nwafu-5A, Qgl.nwafu-5D.2, and Qgl.nwafu-6B, illustrating the explanation rates of phenotypic variation as 6.72–9.59%, 5.62–7.75%, and 6.68–10.73%, respectively. Two QTL clusters were identified on chromosomes 4B and 4D.

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.

Summary Argonaute (AGO) proteins and small RNAs (sRNAs) are core components of the RNA‐induced silencing complex (RISC). It has been reported that miRNAs regulate plant height and grain size in rice, but which AGO is involved in grain size regulation remains unclear. Here, we report that enhanced expression of OsAGO17, a putative AGO protein, could improve grain size and weight and promote stem development in rice. Cytological evidence showed that these effects are mainly caused by alteration of cell elongation. Expression analyses showed that OsAGO17 was highly expressed in young panicles and nodes, which was consistent with the expression pattern of OsmiR397b. SRNA sequencing, stem‐loop RT‐PCR and sRNA blotting showed that the expression of OsmiR397b was reduced in ago17 and enhanced in the OsAGO17 OE lines. Four OsmiR397b target laccase (LAC) genes showed complementary expression patterns with OsAGO17 and OsmiR397b. Combined with the results of immunoprecipitation (IP) analysis, we suggested that OsAGO17 formed an RISC with OsmiR397b and affected rice development by suppression of LAC expression. In conclusion, OsAGO17 might be a critical protein in the sRNA pathway and positively regulates grain size and weight in rice.

Grain weight is one of the most important determinants of grain yield in rice. In this study, QTL analysis for grain weight, grain length, and grain width was performed using populations derived from crosses between major parental lines of three-line indica hybrid rice. A total of 27 QTL for grain weight were detected using three recombinant inbred line populations derived from the crosses Teqing/IRBB lines, Zhenshan 97/Milyang 46, and Xieqingzao/Milyang 46. Of these, 10 were found in only a single population and the other 17 in two or all three populations. Nine of the 17 common QTL were located in regions where no QTL associated with grain weight have been cloned and one was selected for fine-mapping. Eight populations segregating in an isogenic background were derived from one F7 residual heterozygote of Teqing/IRBB52. The target QTL, qTGW10-20.8 controlling grain weight, grain length, and grain width, was localized to a 70.7-kb region flanked by InDel markers Te20811 and Te20882 on the long arm of chromosome 10. The QTL region contains seven annotated genes, of which six encode proteins with known functional domains and one encodes a hypothetical protein. One of the genes, Os10g0536100 encoding the MIKC-type MADS-box protein OsMADS56, is the most likely candidate for qTGW10-20.8. These results provide a basis for cloning qTGW10-20.8, which has an important contribution to grain weight variation in rice. Keywords: Fine mapping, Grain length, Grain weight, Quantitative trait loci, Rice

The importance of vegetable oils and oilseeds, which have an important role in human nutrition and many branches of industry, is increasing day by day. Soybean is one of the most important industrial plants in the world. Despite having the most suitable agricultural land to cultivate soybean, Turkey meets through imports almost all of its soybean needs. The aim of this study is to determine the suitability of soybean genotypes as second crop production for Diyarbakır conditions. In this study, KA-04.03.07, KA-04.06.01, KKMA-118, KSA-26, S-02.14.11, S-03.03.7, Sa-01.08.15 advance lines and Arısoy, Blaze, SA-88 Bravo, Ataem-7, Umut-2002 and GAPSOY-16 varieties were used as materials. According to the results of the research, average grain yield of genotypes was 2,37 t/ha and highest grain yield was obtained from GAPSOY-16 (4,00 t/ha) variety, followed by S-03.03.7 line (3.66 t/ha). The lowest grain yield value was obtained from Umut-2002 (1,33 t/ha) variety. As a result of the correlation analysis, a positive and significant relationship was found between grain yield and thousand grain weight. It is concluded that GAPSOY-16 variety and S-03.03.7 line can be successfully grown as second crop in Diyarbakır province.

Grain size is a major determinant of grain weight, which is one of the components of rice yield. The objective o this study was to identify novel, and important quantitative trait loci (QTLs) for grain size and weight in rice. QTLs were mapped using a BC4F4 population including 192 backcross inbred lines (BILs) derived from a backcross between Xiaolijing (XLJ) and recombinant inbred lines (RILs). The mapping population was planted in both Lingshui (Hainan, 2015) and Fuyang (Zhejiang, 2016), with the short- and long-day conditions, respectively. A total of 10 QTLs for grain length, four for grain width, four for the ratio of grain length to width, and 11 for grain weight were detected in at least one environment and were distributed across 11 chromosomes. The phenotypic variance explained ranged from 6.76–25.68%, 14.30–34.03%, 5.28–26.50%, and 3.01–22.87% for grain length, grain width, the ratio of grain length to width, and thousand grain weight, respectively. Using the sequential residual heterozygotes (SeqRHs) method, qGS7.1, a QTL for grain size and weight, was mapped in a 3.2-Mb interval on chromosome 7. No QTLs about grain size and weight were reported in previous studies in this region, providing a good candidate for functional analysis and breeding utilization.

Background Diethyl aminoethyl hexanoate (DA-6), a plant growth regulator, has many beneficial effects on agricultural production. DA-6 has been applied to many plant species, but the molecular mechanism by which spraying DA-6 after anthesis regulates wheat grain filling is still unknown. Results In this study, we used four DA-6 concentrations: C0 (0 g/L), C2 (2 g/L), C4 (4 g/L), and C6 (6 g/L). The results showed that C4 and C6 led to a significantly higher 1000-grain weight and seed protein content than C0 during two wheat growing seasons. We then subjected samples at 24 days after anthesis (at which point the grain weight increased rapidly) to transcriptome analysis. Flag leaf (L), seed (S), and stem (T) samples under C6 and C0 were used for RNA-seq. The seed samples under C6 compared with C0 (S6vsS0) presented the most differentially expressed genes (DEGs; 2164). Plant hormone signal transduction (p = 1.97 × 10− 4), protein processing in the endoplasmic reticulum (ER; p = 9.04 × 10− 11) and starch and sucrose metabolism (p = 1.90 × 10− 10) pathways were the most markedly enriched pathways in the flag leaves, stems, and seeds, respectively. DEGs involved in sucrose synthesis in the flag leaves, protein processing in ER in the stems, and starch synthesis and protein processing in ER in the seeds were significantly upregulated under C6 compared with C0. Conclusions Overall, we propose a model for spraying DA-6 after anthesis to regulate metabolic pathways in wheat, which provides new insights into wheat in response to DA-6. Electronic supplementary material The online version of this article (10.1186/s12870-019-1925-5) contains supplementary material, which is available to authorized users.

Thousand-grain weight (TGW) is a key component of grain yield in rice. This study was conducted to validate and fine-map qTGW1.2a, a quantitative trait locus for grain weight and grain size previously located in a 933.6-kb region on the long arm of rice chromosome 1. Firstly, three residual heterozygotes (RHs) were selected from a BC2F11 population of the indica rice cross Zhenshan 97 (ZS97)///ZS97//ZS97/Milyang 46. The heterozygous segments in these RHs were arranged successively in physical positions, forming one set of sequential residual heterozygotes (SeqRHs). In each of the populations derived, non-recombinant homozygotes were identified to produce near isogenic lines (NILs) comprising the two homozygous genotypes. The NILs were tested for grain weight, grain length and grain width. QTL analyses for the three traits were performed. Then, the updated QTL location was followed for a new run of SeqRHs identification-NIL development-QTL mapping. Altogether, 11 NIL populations derived from four sets of SeqRHs were developed and used. qTGW1.2a was finally delimitated into a 77.5-kb region containing 13 annotated genes. In the six populations segregating this QTL, which were in four generations and were tested across four years, the allelic direction of qTGW1.2a remained consistent and the genetic effects were stable. For TGW, the additive effects ranged from 0.23 to 0.38 g and the proportions of phenotypic variance explained ranged from 26.15% to 41.65%. These results provide a good foundation for the cloning and functional analysis of qTGW1.2a. Keywords: Fine mapping, Grain weight, Minor effect, Quantitative trait locus, Rice, Grain length, Grain width

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.

The present study was undertaken to determine effectiveness of selection for genotypes tolerant to heat stress using differences in tiller per plant (dTPP), grain weight per plant (dGWPP), grain number per plant (dGNPP), biomass per plant (dBMPP) and spike length (dSL) under the optimum and late sown field condition. A Recombinant Inbred Line (RIL) mapping population derived from the heat sensitive genotype Raj 4014 and heat tolerant genotype WH730 was evaluated for the heat stress over 2 years in a replicated trial under optimum or timely (TS) and late sown (LS) field conditions. Parents and their RILs clearly showing variation with respect to the dTPP, dGWPP, dGNPP, dBMPP and dSL. There was differential response of genotypes under LS as compared to the TS. The field data recorded under precision planting using the dibbling method was very effective in capturing the data under both conditions. Considering the two sowing condition viz., LS and TS, mean of difference in tiller per plant (dTPP) was 1.64. While for grain no. per plant (dGNPP) and grain weight per plant (dGWPP), the mean differences observed between TS and LS were 76.55 and 3.02 g respectively. Difference in spike length (dSL) was 1.09 cm and biomass per plant (dBMPP) showed difference of 8.41 g.

Summary Starch is the most important form of energy storage in cereal crops. Many key enzymes involved in starch biosynthesis have been identified. However, the molecular mechanisms underlying the regulation of starch biosynthesis are largely unknown. In this study, we isolated a novel floury endosperm rice (Oryza sativa) mutant flo16 with defective starch grain (SG) formation. The amylose content and amylopectin structure were both altered in the flo16 mutant. Map‐based cloning and complementation tests demonstrated that FLO16 encodes a NAD‐dependent cytosolic malate dehydrogenase (CMDH). The ATP contents were decreased in the mutant, resulting in significant reductions in the activity of starch synthesis‐related enzymes. Our results indicated that FLO16 plays a critical role in redox homeostasis that is important for compound SG formation and subsequent starch biosynthesis in rice endosperm. Overexpression of FLO16 significantly improved grain weight, suggesting a possible application of FLO16 in rice breeding. These findings provide a novel insight into the regulation of starch synthesis and seed development in rice.

An elite backcrossed inbred line Z550 with increased grains per panicle was identified from advanced backcrosses between Nipponbare and Xihui 18 by simple sequence repeat (SSR) marker-assisted selection (MAS). Z550 carries 13 substitution segments distributed on chromosomes 1, 6, 7, 8, 9, 10, and 12, with an average substitution length of 1.68 Mb. Compared with the Nipponbare parental line, plant height, panicle length, spikelets per panicle, grains per panicle, and grain weight for Z550 were significantly increased. While the grain width of Z550 was significantly narrower, and the seed setting ratio (81.43%) was significantly lower than that of Nipponbare, it is still sufficient for breeding purposes. Quantitative trait loci (QTLs) mapping for important agronomic traits was conducted with the F2 population derived from Nipponbare crossed with Z550 using the restricted maximum likelihood (REML) method. A total of 16, including 12 previously unreported QTLs were detected, with contribution rates ranging from 1.46 to 10.49%. Grains per panicle was controlled by 8 QTLs, 5 of which increased number of grains whereas 3 decreased it. qGPP-1, with the largest contribution (10.49%), was estimated to increase grains per panicle by 30.67, while qGPP-9, with the minimum contribution rate (2.47%), had an effect of increasing grains per panicle by 15.79. These results will be useful for further development of single segment substitution lines with major QTLs, and for research of their molecular functions via QTL cloning.