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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.

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

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.

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.

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

In the semi-arid regions of the world, irrigation and fertilization are essential for cereals growth and production because of water shortages and unfertile soils. However, inappropriate water and fertilizer management always causes unstable grain weight and yield. This study aims to explore the responses of grain filling characteristics, grain weight and productivity of winter wheat to varying water and fertilizer supplies. A three-year (2014–2017) experiment was conducted on winter wheat (Triticum aestivum L. ‘Xinong 979’) under drip fertigation, with three irrigation rates and three fertilization rates. The temporal dynamics of grain weight was simulated using determinate-growth equation. The appearance time of maximum filling rate (tm) and growth termination time (te) increased as fertilization rate increased, whereas the maximum and average filling rate increased and then had a slight decrease. The tm and te decreased with the increase of water deficit, the mild water deficit obtained higher grain filling rate. The grain weight percentage of spike weight (GPS) and spike moisture content (SMC) had extremely significant correlations with grain weight. GPS tended to decrease one week before maturity, and declined with the increase in water stress. SMC decreased in a parabolic form, and exhibited a dramatic decline about one week before maturity. With the increase of water or fertilizer supply, the grain weight firstly increased and then decreased, where the mild water deficit and appropriate fertilization improve grain filling and productivity of winter wheat.

Rice is a staple food for more than 50% of the world population, therefore a sustainable sufficient rice production is a key strategic issue to ensure their food security. In line with this issue, many studies have been and are being carried out to improve the rice production. In this report, we describe the results of our study to apply a sustainable and clean technology to increase the total grain weight per plant of rice variety of MR 219. In this study, a 2-D clinostat was utilised to treat the rice seeds (variety MR 219) to enhance its total grain weight per plant. A 23 full factorial design was employed to investigate the effects of three different factors (rotation period, rotation speed and distance of the seeds from the center of clinostat) on the total grain weight per plant. The treated seeds were planted in an open area and the total grain weight per plant was measured after harvesting the plants. Analysis of variance, the F-test and the Student’s t-test at 95% of confidence level shows that the distance of seeds from the center of clinostat affects the total grain weight per plant significantly.

Contact toxicity of filter cake and Triplex powders from Ethiopia were evaluated against the rice weevil, Sitophilus oryzae (Linnaeus). The study was aimed at determining the lethal and effective concentrations and times for both powders against S. oryzae. The lethal concentrations for 50 and 99% mortality (LC50 and LC99) of filter cake and Triplex against S. oryzae were determined at 14 d after exposing 10 adults for 12 h to concrete arenas inside Petri dishes treated with filter cake concentrations of 0.5–8 g/m2 and Triplex concentrations of 1–9 g/m2. Lethal times for 50 and 99% mortality (LT50 and LT99) were determined at 14 d after exposing adults for 1–24 h to 3 g/m2 of filter cake and 9 g/m2 of Triplex. Effective concentrations (EC50 and EC99) and times (ET50 and ET99) for 50 and 99% reduction of adult progeny production were determined from reduction in adult progeny production relative to production in control treatments at 42 d after exposure to filter cake and Triplex. LC50 and LC99 values for S. oryzae adults were 0.70 and 8.49 g/m2, respectively, when exposed to filter cake and 2.27 and 21.38 g/m2, respectively, when exposed to Triplex. The corresponding LT50 and LT99 values were 3.13 and 27.21 h, respectively, for filter cake and 4.72 and 38.60 h, respectively, for Triplex. EC50 and EC99 values for progeny reduction were 0.57 and 7.95 g/m2, respectively, for filter cake and 2.77 and 18.82 g/m2, respectively, for Triplex. The corresponding ET50 and ET99 values were 2.57 and 17.73 h, respectively for filter cake and 3.39 and 24.74 h, respectively, for Triplex. S. oryzae exposed to filter cake produced significantly less number of insect damaged kernels and grain weight loss than those exposed to Triplex. Filter cake was more efficacious against S. oryzae than Triplex.

The efficacy of filter cake and Triplex powders applied to wheat was evaluated in the laboratory against the maize weevil, Sitophilus zeamais Motschulsky and rice weevil, Sitophilus oryzae (Linnaeus)—two most common insect pests associated with stored grain in Ethiopia. Efficacy of these powders was determined by exposing 20 adults of each species to 100 g of wheat treated with 0, 100, 500, 700 and 1000 mg/kg of filter cake and Triplex. Adult mortality was determined 7 and 14 d after exposure. In addition, adult progeny production, percentage of insect damaged kernels, and percentage of grain weight loss at each species-powder-concentration-time combinations were determined after 42 d. The 7 and 14 d mortality was 100% for adults of both species exposed to 1000 mg/kg of filter cake; only the 14 d mortality of Sitophilus species was 100% for adults exposed to 700 mg/kg. Mortality of S. oryzae adults was 100% when exposed for 14 d to1000 mg/kg of Triplex. Mortality of S. zeamais never reached 100% in any Triplex treatments. Adult progeny production of S. zeamais was completely suppressed at filter cake concentrations of 700 and 1000 mg/kg, whereas 1000 mg/kg was necessary for complete suppression of S. oryzae adult progeny production. Complete suppression of adult progeny production was not observed in any Triplex treatments. Complete reduction in percentage of insect damaged kernels and percentage of grain weight loss were obtained when S. zeamais and S. oryzae adults were exposed to 1000 mg/kg of filter cake; similar reductions with S. zeamais occurred only at 1000 mg/kg of Triplex. In the case of S. oryzae, complete reduction of insect damaged kernels and grain weight loss were not achieved at any concentration of Triplex. These powders can be used as alternatives to chemical insecticides for management of Sitophilus species.

Green gram is extremely vulnerable to insect attack during storage. Hermetic storage provides an important insect management strategy. We have conducted laboratory studies using hermetic bags like PICS®, Grain Pro®(GPB), SaveGrain®(SGB), Ecotact bags®(EHB), and conventional storage bags like White Polypropylene (WPB) and Jute Bags (JB). The insect used for the study was Pulse Beetle (Callosobruchus chinensis). Variables like moisture content, damaged grains, weight loss, and grain color were observed to assess the impact of storage for six months in the said bags. There is reduction in oxygen level for all hermetic bags under infested condition (6.4%) and non-infested (7.0%) condition from initial level of 20%. The grain moisture content and grain weight loss due to damaged caused by insects increased in WPB and Jute bags, but remains unchanged in hermetic bags. There was a significant (F6,14 = 2164; p

Argentina is one of the most important maize producers worldwide, and is internationally known for producing hard endosperm maize. The physicochemical characteristics of the maize grain directly affects the milling yield of large endosperm grits, the main dry milling product, and specific grain quality values are demanded by industry. Argentinean traditional maize grains used to have optimum hardness quality for dry milling, but higher yielding newer commercial genotypes slowly moved from hard endosperm flints to semi-dent or dent softer endosperm grain type. Our objective was to describe how grain hardness and composition changed in commercial maize genotypes released in Argentina from 1965 to 2016 as an indirect breeding effect when selecting for on-farm yield. Measured traits were yield, individual grain weight, dry milling quality (test weight, floaters, grain vitreousness, 8 mm screen retention), and composition (oil, protein, starch). There were clear genotype differences in yield (p

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.

The Mars Surface Wind Tunnel at NASA Ames Research Center is used to simulate windblown (aeolian) movement of sand and dust on the martian surface. Because objects weigh less on Mars, the tunnel employs lighter sand in the form of crushed walnut shell to compensate for Earth’s higher gravity. The tunnel is thus operated on the principle of ‘grain-weight similitude’. This approach enables successful replication of transport thresholds but it leads to major discrepancies for other aspects of grain behavior.

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.

The endosperm contributes approximately 80% of the final kernel weight in maize. Plant hormones that affect cell proliferation might increase endosperm cells and establish greater kernel sink capacity, which would improve grain yield. In this study, 6-benzyladenine (BA) and brassinolide (BR) were separately sprayed at tasseling to regulate kernel endosperm cell division, and EDAH (a mixture of ethephon and diethyl aminoethyl hexanoate) was foliar applied at the jointing stage to enhance lodging resistance. The results showed that the two hormones sprayed at tasseling could hamper leaf senescence, improve photosynthesis and significantly increase the number of kernel endosperm cells by 6.2-40.4%, resulting in a high grain filling rate and high kernel weight. Additionally, the tasseling treatments increased grain yield by 2.9-16.0% in both years. There were no significant differences between EDAH and control conditions in sink capacity and yield. The correlation analysis suggested that grain weight and yield had a close correlation with the number of endosperm cells and the filling rate in the lag stage. We concluded that the lag stage played a vital role in constructing sink capacity, and treating maize with BA or BR at tasseling can apparently increase the source and sink capacity to improve the grain filling rate and yield.

Annual crops accommodate environmental variation through grain number, whereas grain weight is more stable. Grain number is determined in a species-specific window which has been established for many crops, but not for oat. Field trials were established at two sites in southern Australia and in one site in southern Chile where successive, single 14-d shading periods were applied from crop establishment to maturity to identify the developmental window when the crop is most responsive to stress. Three oat varieties were compared in Australia (Mitika, Williams and Wintaroo) and two in Chile (Mitika and Yallara). Unshaded controls yielded from 327 g m −2 in Australia to 747 g m −2 in Chile. The overall pattern of yield response to time of stress was similar to that of wheat; it spanned the period from stem elongation (GS31) to about 10 days after anthesis. In line with theory, most of the yield response was mediated through response in grain number; further, the two environments in Australia where reduction in grain number in response to stress shortly before anthesis was larger, individual grain weight increased with shading. Grains per panicle was more responsive to stress than panicles per m 2 , in contrast to other cereals. The critical period is often assumed to be species-specific. However, our limited comparison of varieties suggests that there might also be varietal differences in oat. Interaction between time of shade and variety was significant for harvest index in all locations. Hence, we propose genotype-dependent response to time of stress is worth exploring.

In a large comparison of experimental and published data across a wide range of environmental conditions, a cross-over interaction of durum vs . bread wheat yield was found to be the reverse of expectations, where the former would outyield the latter under low-yielding conditions and vice-versa . In this study, we aimed to establish the physiological basis of this species cross-over interaction, analysing whether it was established before or after anthesis and to determine if it was related to differences in sink-strength. Our study indicates that the consistent species-by-environment interaction for yield is the consequence of a few traits related to sink-strength that are determined around anthesis. Thus, differences in the spike weight and N accumulated at anthesis, which produced important variations in the number of grains and presumably generated differences in sink-strength, seemed to be involved. This conclusion is supported by the strong relationship between grain yield and the biomass produced during grain filling, in addition to the fact that the variation in individual grain weight, as well as its rate or the duration of grain filling, was poorly related to yield and the post-anthesis biomass.

Temperature and solar radiation during grain filling are the main drivers of grain weight and composition in several crops. While significant progress has been done on the effect of solar radiation intercepted by the plants (ISR) on grain weight (GW, mg) and oil content (OC, mg grain−1) of sunflower (Helianthus Annus L.), the effects of temperature on these traits are far from clear. As temperature affects the rate of plant development, increasing temperature would shorten grain filling duration and so, the critical period for ISR effect on GW and OC (indirect effect of temperature). However, direct effects of temperature non-mediated by ISR accumulation could also affect these traits. The objectives of this work were a) to characterize the responses of grain weight and oil content to mean temperature during grain filling in two traditional sunflower hybrids and b) to determine whether these responses can be exclusively explained by changes in ISR or any direct effect of temperature should also be considered. Two experimental approaches have been used to address these objectives: i) temperature manipulation at constant incident radiation in growth chambers; ii) modification of radiation interception in the field in different locations and years (different mean temperatures). Growth chamber experiments showed that GW and OC respond to temperature in a plateau lineal shape. At low incident radiation such as that of growth chambers, temperature effects on GW can be exclusively explained by reductions in ISR, while both direct and indirect effects of MT are evident on OC. Results obtained in field experiments confirmed this behavior at low radiation. Both GW and OC exponentially increased up to a maximum with ISR disregarding MT. Mathematical models were established to describe the responses of GW and OC to MT and ISR. These models consider MT x ISR interactive effects on GW; and MT - ISR additive effects on OC. The combination of growth chamber and field experiments observations allowed to unravel different mechanisms underlying the responses of GW and OC to temperature: at low incident radiation intensity, increasing temperature decreased GW exclusively by reducing ISR accumulation (indirect effects) while at higher radiation, temperature displays both direct (non-mediated by ISR) and indirect (ISR mediated) effects on GW. OC is affected by temperature in both direct and indirect way disregarding ISR. This work constitutes an important contribution towards understanding the effect of temperature during grain filling on sunflower yield and its relationship to solar radiation effects.

Grain growth and leaf senescence are the main processes during post-silking in maize. An unanswered question is how changes in sink strength (the number of grains to be filled) affect leaf senescence. We studied the effect of changes in the source-sink ratio during grain filling on the dynamics of green leaf area and photosynthetic rate. Maize plants were exposed to ear removal, pollination prevention, degraining or defoliation treatments during post-silking in two sowing dates. Green leaf area, leaf photosynthetic rate and leaf greenness were periodically measured. At maturity, yield, grain weight, and stem dry weight were determined. Green leaf area loss showed a first phase of slow senescence followed by a second phase of rapid senescence in all conditions. The response of green leaf area duration (GLAD) to the source-sink treatments depended on environmental conditions: ear removal increased GLAD while defoliations reduced it in the early sowing date, though GLAD was unaffected by these treatments in the late sowing date. But any change in senescence was less than proportional to the changes in the source-sink ratio. Leaf photosynthetic rate or leaf greenness (SPAD) did not change with the source-sink treatments. Defoliation caused a remarkable remobilisation of reserves from the stem, which did not fully mitigate the reduction in grain weight. It is concluded that (i) manipulations of source-sink balances modified slightly leaf longevity but not the functionality of the remaining leaf area (leaf photosynthetic rate), the response of GLAD being dependant on environmental conditions, and (ii) grain weight was more susceptible than GLAD to reductions in source-sink ratio. LGA held a ‘Juan de la Cierva’ post-doctoral contract funded by the Spanish Ministry of Science during the experimental phase of this research. Funding was provided by Project 8031 of the Regional Fund for Agricultural Technology (FONTAGRO).

This study was designed to determine the quantitative and qualitative losses of stored grains that arise from insect infestation in three districts of southwestern Ethiopia. One district was selected from each zone based on the production potential of the target crops (maize, sorghum, wheat and fababean). A total of 240 farmers’ stores from all districts were randomly selected. The grain samples used in the present study were stored for 5 different time periods, ranging from 1 to 5 months and from the same farmers’ stores, to determine grain weight loss, insect damage, and nutritional losses. Grain damage showed significant differences over the storage periods across the study districts. A similar trend was observed for weight loss for each of the grains in all districts. The moisture content of the grains decreased along the storage duration. Crude protein and crude fat contents significantly decreased as the storage duration increased in all traditional storage types. Furthermore, the crude fibre and ash contents of the different grain types significantly increased as the storage duration increased in all storage types. These results demonstrated that traditional storage structures have a substantial effect on quantitative and qualitative losses of stored grains. This finding has great implications for food security and hidden nutritional deficits in society. Thus, there is a need to develop and disseminate storage technologies that minimize losses and that are affordable for small farm holders.

The use of new raw materials in brewing has many advantages. They allow the production of new beers with interesting flavours and aromas. In addition, the use of certain raw materials makes it possible to reduce production costs or improve various quality characteristics, such as taste, colour or turbidity. However, very often new raw materials, other than barley malt, cause difficulties in brewing, e.g. too long saccharification or filtration time, too low wort extract and thus alcohol content in the beer, the need to add exogenous enzymes, etc. In this study, the potential of a new raw material, i.e. tritordeum, for beer production was examined. The results of grain analysis showed no significant differences between tritordeum and barley malts for 1000 grain weight, while less glassy grains and better grading were determined in the tritordeum sample. The analysis of the influence of different proportions of tritordeum malt in the mixture (from 0 to 100%) on the course of subsequent stages of wort production revealed that the times of saccharification and lautering observed, as well as colour and turbidity were comparable to those of barley malt. Significant differences observed included the slightly acidifying effect of the tritordeum malt and a higher level of FAN (Free Amino Nitrogen), and lower level of glucose in the 100% tritordeum variant. The alcohol content obtained in beer, the real extract, and the content of metal ions were at levels similar to those of the control sample. The results obtained prove the high potential of tritordeum malt for brewing industry. Moreover, its use in a wide range of proportions from 0% to 100% did not cause any technological difficulties at subsequent stages of beer production.

Plant anthocyanins can act as antioxidants and help in prevention of cardiovascular diseases, diabetes, inflammation, cancer, obesity and aging. In the current study, anthocyanin rich blue, purple and black wheat lines with alien chromosome or its arm and adapted to local growing conditions were developed from low yielding exotic donor lines. Selected pigmented lines with commercial potential, had yield and thousand grain weight equivalent to the high yielding cultivars. Higher anthocyanin content was observed in black followed by blue, purple and amber wheat lines. 22 different anthocyanins could be identified from blue, 23 from purple and 26 from black wheat lines. Purple wheat lines exhibited higher peak intensities of acylated anthocyanidins. Chroma and hue values assisted in the efficient and reliable selection of compound grain colors. Cryo-microtome seed sections indicated presence of purple color in the pericarp all around the seed. The blue color was present in the aleurone layer all around the seed except around the embryo.

Wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) crops are exposed to warm nights during their growing seasons and this trend is unlikely to change. The aim of this work was to evaluate the effect of higher post-anthesis night temperatures on field-grown crop yield, focusing on final grain weight determination. Experiments combined: (i) two well-adapted crops with similar phenology: bread wheat and two-row malting barley, under (ii) two temperature regimes: ambient and high night temperatures from 10 days after anthesis to physiological maturity during (iii) two contrasting growing seasons in terms of radiation and temperature: late sowing in 2011 and early sowing in 2013. The night temperature increase (ca. 4.1 °C) was achieved using purpose-built heating chambers placed on the crop at 7 pm and removed at 7 am every day during the heating period. Across growing seasons and crops, the average minimum temperature during that period ranged from 14.3 °C to 21.9 °C. Thousand grain weight was reduced by ca. 3% per °C of night temperature increase, similarly for wheat and barley, causing a grain yield reduction of ca. 4% per °C. An accelerated development under high night temperatures led to a shorter effective grain filling period, reducing the final grain weight. The lack of consistent impact on source availability between crops and seasons, measured as senescence and stem water soluble carbohydrates, as well as a similar impact in magnitude and direction on individual grain weight for different grain positions along wheat or barley spikes, suggest that the negative effects of warm nights on grain weight were directly related to processes within the grain itself. Fil: García, Guillermo Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Serrago, Roman Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Dreccer, M. Fernanda. The University Of Queensland; Australia Fil: Miralles, Daniel Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina

The present research work was conducted during winter 2013–14 and 2014–15 at Agricultural Research Station, Chitral-Pakistan. Objectives of the present research was to determine the mean performance and correlations of parents, direct and reciprocal crosses in bread wheat varieties for different yield components under 6X6 diallel combinations. Days to heading of parents exhibited highly significant differences for plant height, grains per spike, grain weight per spike, 100-grain weight and grain yield while significant for days to heading and days to maturity and non significant for biological yield. Both direct and reciprocal crosses showed highly significant differences for all the studied traits. Correlations of grain yield with 100-grain weight of parents was significant and positive while grains per spike and grain yield with plant height of direct crosses was significant and positive and grain yield with biological yield of reciprocal crosses was highly significant and positive. Maximum days to heading of parent (Dirk), direct cross (NR-218 X Dirk), reciprocal cross (Pirsabaq-2013 X Dirk) and difference were 171 days, 170 days and 172 days, and 6 days, respectively. Parent (Dirk), direct (NR-218 X Dirk) cross, reciprocal cross (Dirk X pirsabaq-2013) and difference were 190 days, 184 days, 189 days and 7 days, respectively. Maximum 138.97 cm, 115.00 cm and 129.17 cm plant height was recorded by parent (Dirk), direct cross (NR-218 X Dirk) and reciprocal cross (Pirsabaq-2013 X Dirk) while the maximum difference was 25.1 cm. Parent (N-46), direct cross (NR-218 X N-46), reciprocal cross (N-46 X Dirk) and difference for grains per spike was 61 grains, 66 grains, 71 grains and 22 grains and was maximum. Recorded maximum grain weight per spike of parent (Fakhr e Sarhad), direct cross (Dirk X Pirsabaq-2013), reciprocal cross (Fakhr e Sarhad X Pirsabaq-2013) and difference were 3.33 g, 4 g, 5 g and 3 g, respectively. Parent (Dirk), direct cross (Dirk X N-46), reciprocal cross (Fakhr e Sarhad X Pirsabaq-2013) and difference for 100-grain weight was 9 g, 6 g, 7 g and 2 g and was maximum. Maximum biological yield for parents (NR-218), direct cross (NR-218 X Dirk), reciprocal cross (Fakhr e Sarhad X Dirk) and difference were 1.1001 kg/Plot, 0.6853 kg/Plot, 1.15 kg/Plot and 0.8147 kg/Plot, respectively. The recorded maximum grain yields for parent (Suliman-96), direct cross (Dirk X N-46), reciprocal cross (Dirk X NR-218) were 1.0175 kg/Plot, 0.575 kg/Plot, 1.405 kg/Plot and 0.895 kg/Plot, respectively.

In recent decades, research in barley has led to improvements in several biochemical and chemical characteristics (e.g. protein, starch, β glucans) associated with malt composition and end product quality (e.g. beer). Although lipids and fatty acids (FA) represent between 1 to 3% of the grain weight (dw), they can play an important role in barley grain and malt derived materials. However, the role of lipids and FA in both barley and malt quality is still not well understood. The aim of this article is to provide an overview on the role of lipids and FA in the chemical and industrial properties of barley grain, malt and wort.

The grain, flour, dough and noodle making properties of Indian durum wheat varieties were evaluated. Varieties having higher grain weight had lower hardness and higher yellow pigment content. Gluten performance index showed positive correlation with α-helix and negative with intermolecular+antiparallel-β-sheets in gluten. The proportion of extracted polymeric proteins was related to dough strength. Elastic (G') and loss (G″) modulus of dough were positively correlated to intermolecular+antiparallel-β-sheets and negatively with β-turn+ β-sheets proportion of dough and gluten. PDW291 with exceptionally higher G' and G″ and best noodle making properties showed the presence 90 kDa and 88 kDa polypeptides corresponding to 14+15 and type 2 banding pattern.

Favorable agronomic traits are important to improve productivity of popcorn. In this study, a recombinant inbred line (RIL) population consisting of 258 lines was evaluated to identify quantitative trait loci (QTLs) for nine agronomic traits (plant height, ear height, top height (plant height subtracted ear height), top height/plant height, number of leaves above the top ear, leaf area, stalk diameter, number of tassel branches and the length of tassel) under three environments. Meta-analysis was conducted then to integrate QTLs identified across three generations (RIL, F2:3 and BC2F2) developed from the same crosses. In total, 179 QTLs and 36 meta-QTLs (mQTL) were identified. The percentage of phenotypic variation (R2) explained by any single QTL varied from 3.86 to 28.4%, and 24 QTLs with contributions over 15%. Nine common QTLs located in the same or similar chromosome regions were detected across three generations. Five meta-QTLs were identified including QTLs in three independent studies. Seven important mQTLs were composed of 11–26 QTLs for 4–7 traits, respectively. Only 11 mQTLs were commonly identified in the same or similar chromosome regions across agronomic traits, popping characteristics (popping fold, popping volume and popping rate) and grain yield components (ear weight per plant, grain weight per plant, 100-grain weight, ear length, kernel number per row, ear diameter, row number per ear and kernel ratio) by meta-QTL analysis. In conclusion, we identified a list of QTLs, some of which with much higher contributions to agronomic traits should be valuable for further study in improving both popping characteristics and grain yield components in popcorn.

Breeding activities in Lebanon have attributed limited interest to barley and landraces have not been exploited before. In this study, 50 Lebanese barley landraces were experimented rainfed in Northern Bekaa in comparison with two checks, Assi and Rihane-3. Two field trials were conducted, the first at 1000 m a.s.l. and 171.6 mm precipitations, and the second at 648 m a.s.l. and 119.4 mm. Out of the 50 landraces, five named LR9, LR12, LR16, LR30 and LR32 were early in heading and maturity in both trials, similarly to checks. Landraces showed a large variability for yield components, particularly grain number per spike and thousand grain weight. Number of spikes per plant and grain weight per plant were twice greater in Kfardan than Qaa location. The best plant productivity in Kfardan was 3.8 g/plant recorded for LR11 vs. 3.46 g/plant obtained with LR33 in Qaa. The higher yield was recorded in Qaa trial with 255 g/m2 for LR31 and 244 g/m2 produced by LR32, while 211 and 200 g/m2 were recorded in Rihane-3 and Assi checks respectively. Principal components analysis allowed to distinguish several landraces that were clustered next to the checks sharing similar features of plant height, spike length and yield per m2. At the level of individual plants and based on the grain yield per plant, a set of 47 plants were found to be similar or even greater to the checks. These plants should be further evaluated for their agronomic performance within national breeding program.

The introgression of awns as a source of photoassimilates during grain filling has received has long been of particular attention in wheat. Although the benefits for average grain weight (AGW) seem consistent, those for yield still remain unclear, and the causes for the improved AGW have not been examined. In this study we carried out three field experiments. In two of them, one in CIMMYT (Mexico) and the other in Lleida (Spain), we compared awned-awnless near isogenic lines (NILs) subjected to defoliation and degraining during the effective period of grain filling, whilst in another experiment we analysed the responses of modern cultivars to awn detachment 10 days after anthesis under two nitrogen levels. There were not consistent differences in yield between the awned-awnless NILs neither across the locations nor across genetic backgrounds. This lack of effect on yield was associated with a compensatory effect of the presence of awns on decreasing grain number while increasing AGW. The manipulation treatments did not consistently affect AGW neither in the NILs nor in the modern cultivars. Focusing on the responses of the NILs, firstly there were some statistically significant responses in AGW but they were both mostly very small and inconsistent between defoliation and degraining treatments as well as between genetic backgrounds. Secondly these responses failed to be consistently more noticeable in the awnless than in the awned lines (as expected if the presence of awns increases AGW through increasing photosynthetic capacity during grain filling). The increase on AGW due to the presence of awns seemed ascribed to both an indirect and a direct effect. The former would simply reflect the consequence of awns reducing grain number: this would naturally be the consequence of an increased failure of distal florets to become fertile which would have reduced the proportion of grains constitutively smaller as well. A direct true effect on the capacity of the grains to grow also emerged with the analysis of individual size of each particular grain for the awned-awnless NILs revealing a constitutively higher potential size in the awned NILs, even for the largest grains. Funding for the experimental work at Lleida was provided by project AGL2015-69595-R from the Spanish Research Agency (AEI). Part of the funding for the experiment was supported by BASF Agricultural Solutions. RSB was supported by Juan de la Cierva program JDC-Formación (FJCI-2016-28164). JWK held a pre-doctoral research contract from the Government of Catalonia. CRA and GM were supported by the Sustainable Modernization of Traditional Agriculture (MasAgro) an initiative from the Secretariat of Agriculture and Rural Development (SADER) and CIMMYT and the International Wheat Yield Partnership (IWYP). JLA acknowledges the support of ICREA Academia, Generalitat de Catalunya, Spain.

An extreme high temperature during grain filling is an important environmental factor that reduce the yield and quality of rice. In this study, we compared the grain appearance, composition and starch structure of four rice varieties response to high temperature during grain filling. The results obviously revealed that two indica AUS varieties Halwa and Jamir showed more tolerance to high temperature during grain filling than either the japonica Nipponbare or another AUS rice DJ24. The data showed that Halwa and Jamir presented less chalkiness, less grain weight loss, less change of endosperm components as well as starch structure than Nipponbare and DJ24 under high temperature treatment. Hence, the results implied that Halwa and Jamir might be useful targets to further identify genetic mechanism response to high temperature, at least during grain filling and endosperm development. Moreover, these AUS varieties have potential application value in further breeding of rice with good quality and heat tolerance.

Six modern rice cultivars, including three indica and three japonica cultivars were exposed to 100 ppb ozone (8 h per day) and control conditions throughout cropping season in 2016 to 2017 at Yangzhou, China. Ozone decreased plant height and inhibited tillering development as well as panicle number per plant of all cultivars, but had no effect on the productive tiller ratio. Ozone significantly decreased spikelet number per panicle, spikelet number per plant, fully-filled grain percentage and fully-filled grain weight, resulting in yield decrease by 39.3% on average for all cultivars and by 42.6 and 34.4% in the indica and the japonica groups, respectively. The response of aboveground biomass to ozone was similar to that of yield, albeit with a lower decrease, which led to a 7.6% decrease in harvest index. In terms of grain positions (grains attached to the upper primary rachis: superior spikelet (SS); grains attached to the lower secondary rachis: inferior spikelet (IS), and the remaining grains: medium spikelet (MS)), the ozone-induced change in yield traits (yield, spikelet number per panicle, spikelet number per plant, fully-filled grain percentage, and empty grain percentage) followed the order IS > MS > SS, as indicated by the significant interaction between ozone and grain position. Although ozone had negative effects on all yield traits, only ozone-induced reduction in spikelet density (spikelet number per panicle and or spikelet number per plant) was significantly correlated to yield loss. Grain yield showed significant ozone by cultivar and ozone by year interactions, indicating ozone impacts on rice yield varied with meteorological conditions and cultivars.

Highlights • Linear and consistent grain yield genetic gains in the HRWYT has been observed. • Several best performing lines were common in both high and low rainfall environments. • The genetic gains were explained by paralleled increases in grain weight, day to maturity and grain filling period. • These results indicate continuous genetic progress and yield stability in the HRWYT germplasm developed by CIMMYT., The effects of climate change together with the projected future demand represents a huge challenge for wheat production systems worldwide. Wheat breeding can contribute to global food security through the creation of genotypes exhibiting stress tolerance and higher yield potential. The objectives of our study were to (i) estimate the annual grain yield (GY) genetic gain of High Rainfall Wheat Yield Trials (HRWYT) grown from 2007 (15th HRWYT) to 2016 (24th HRWYT) across international environments, and (ii) determine the changes in physiological traits associated with GY genetic improvement. The GY genetic gains were estimated as genetic progress per se (GYP) and in terms of local checks (GYLC). In total, 239 international locations were classified into two groups: high- and low-rainfall environments based on climate variables and trial management practices. In the high-rainfall environment, the annual genetic gains for GYP and GYLC were 3.8 and 1.17 % (160 and 65.1 kg ha−1 yr−1), respectively. In the low-rainfall environment, the genetic gains were 0.93 and 0.73 % (40 and 33.1 kg ha−1 yr−1), for GYP and GYLC respectively. The GY of the lines included in each nursery showed a significant phenotypic correlation between high- and low-rainfall environments in all the examined years and several of the five best performing lines were common in both environments. The GY progress was mainly associated with increased grain weight (R2 = 0.35 p < 0.001), days to maturity (R2 = 0.20, p < 0.001) and grain filling period (R2 = 0.06, p < 0.05). These results indicate continuous GY genetic progress and yield stability in the HRWYT germplasm developed and distributed by CIMMYT.

The grain diameter and weight are important traits in lentil influencing grain yield, cooking time and consumer preference. In this study association mapping panel of ninety-six diverse genotypes representing genotypes from India and Mediterranean region was assessed at three locations in India (Delhi, Indore, and Dharwad representing different cultivation zones) for grain size and weight. Hundred grain weight ranged from 1.24 to 5.8 g across the locations and grain diameter from 1.91 mm to 5.98 mm. Marker-trait associations (MTAs) were analysed with 425 markers (365 EST-SSRs and 60 genomic markers) using mixed linear model (MLM). The characterization of genetic variation using STRUCTURE analysis revealed the presence of six sub-populations. Neighbor-Joining method of clustering also confirmed six clusters. The MLM approach identified association of PBALC 224 (R2 value 7%) with grain diameter and GLLC 614 (R2 value of 13%) and PBALC 29 (R2 value of 15%) with grain weight. The reported SSRs exhibited the marker-trait association across the all studied environments. The identified SSRs exhibited consistent performance across three locations. This study can help in breeding new lines with enhanced grain diameter and weight using marker-assisted selection (MAS) in lentil.

In wheat (Triticum aestivum L.) canopy architecture influences light penetration into the canopy and radiation use efficiency particularly during the period between stem elongation and anthesis which is the critical time for the determination of yield. Despite large differences in canopy architecture among spring wheat genotypes, ranging from erectophile to planophile upper leaves, there is little prior evidence to suggest that selection for canopy architecture influences yield. In this study we evaluated the variation for canopy architecture in a 4-way MAGIC population (n=∼ 1000 lines) developed from 4 Australian commercial spring wheats and an 8-way MAGIC population (n=∼ 300 lines) developed from 3 Australian and 5 northern hemisphere commercial wheats. The 4-way population was grown at both an irrigated and a dryland site in southern New South Wales whereas the 8-way population was grown at the irrigated site. We also measured grain yield, plant height and crop development stage at the irrigated site. Using a smaller subset of lines which we grouped into either erectophile or planophile we studied how canopy architecture influences grain yield and associated yield traits (above-ground biomass (AGBM), harvest index, yield components, flowering time and height). The grain yield in the latter experiments varied from 5 to 6 t ha−1. Averaged over two years and two sowing dates in each year lines that were erectophile yielded 13% more than the planophile lines and most of this yield advantage was associated with a higher AGBM (11%). Erectophile lines had 24% more grains per unit area but a 9% lower grain weight. Erectophile lines flowered 2 days later than planophile lines and they were 7 cm shorter. Lodging, although rare in these studies, was more evident in the planophile lines. In both MAGIC populations the most erectophile lines yielded 24% more grain than the most planophile lines. Mapping was conducted on the 1000 lines from the 4-way MAGIC population grown at the irrigated and the dryland site. It showed that genetic control of canopy architecture was complex but QTL were generally repeatable at both sites. Significant QTL were identified on most chromosomes. G x E was low for canopy architecture as the scores were repeatable across years (r2 = 0.85). This trait opens the way to improve wheat yields via increasing crop biomass which in the past has been largely intractable in breeding programs.

The objective of the current investigation was to study the plasticity of the oat panicle together with associated changes in leaf area and grain weight as affected by seed rate and tiller order. Plants (cv. Husky) were sampled from autumn sown seed rate experiments (100, 200, 300, 400, 500 seeds/m2) in 2016 and 2017 after anthesis and separated into their component tillers. The number of primary, secondary and tertiary grains on each whorl of the panicle of each tiller were counted, green leaf area per tiller was measured and, in 2017, the number of green leaves per shoot in addition to leaf length and leaf width were measured. At grain maturity, plants were sampled from three treatments (100, 300, 500 seeds/m2) and separated into their component tillers. The number of primary, secondary and tertiary grains on each whorl were counted and weighed. Primary and secondary grain numbers on all mainstem whorls except the uppermost whorl increased significantly as seed rate decreased, the largest changes being on the bottom whorls. There were also significant increases in green leaf area per stem as seed rate was decreased due to increases both in the number and size of leaves. Grain numbers per whorl decreased significantly with increasing tiller order but green leaf number per stem and leaf area per grain increased with increasing tiller order. The number of secondary grains per panicle was tightly correlated with the number of primary grains per panicle irrespective of seed rate or tiller order. Seed rate had no significant effect on the weight of primary or secondary grains but primary and secondary grain weights were significantly greater on the first tiller compared to the mainstem and second tiller. The oat panicle is a highly plastic organ, the plasticity of the oat panicle contributes to yield stability. Grain weight stability is preserved across a wide range of panicle sizes by changes in leaf area per stem and by the highly stable nature of the relationships between primary and secondary grain numbers and between primary and secondary grain weight.

Understanding the effect of past durum wheat breeding activities on the cultivar×environment (C×E) interaction of yield and yield components may guide future breeding strategies. A historical series of 24 cultivars released in Italy and Spain during the 20th century was grown in 13 environments with average yields ranging between 1425 and 6670kgha−1. The most important environmental factors affecting the C×E interaction for yield were reference evapotranspiration before anthesis and water input during grain filling. The response of cultivars to environmental variables in terms of yield and yield components was associated to the allelic composition for the Rht-B1 locus. Improved semi-dwarf cultivars (carrying the Rht-B1b allele) had the best yield performance in environments with high water input after anthesis, while tall cultivars (carrying allele Rht-B1a) were better adapted to environments with high evapotranspirative demand before anthesis and low water input after it. The introduction of the Rht-B1b allele improved the capacity of the crop to respond to water availability during grain filling by increasing the number of grains spike−1 and grain weight. Yield increases due to breeding caused a loss of stability from the static viewpoint, but not from a dynamic approach based on the superiority measure (Pi). Some semi-dwarf cultivars maintained the levels of yield stability characteristic of the old tall ones. Our results suggest that durum breeding in the 20th century enhanced the response of the crop to environmental improvements.

Future increases in grain number may be achieved through improving fruiting efficiency (FE; grains set per unit spike dry weight at anthesis). In recent experiments it was found a negative relationship between the average weight of the grains and FE. The objective of this paper was to determine whether this negative relationship was constitutive (i.e. the increased FE caused all grains to be smaller) or resulted from the increased proportion of grains of smaller potential size. Four experiments, involving 8 different environmental conditions, were carried out during two consecutive growing seasons (2008–2009 and 2009–2010) in which two durum wheat cultivars contrasting in FE and average grain weight were compared. In these conditions we determined FE and carried out a comprehensive study analysing in detail the weights of each individual grain along each of the spikelets. Averaging all experimental conditions, there was a negative relationship between average grain weight (GW) and fruiting efficiency (FE). Donduro with low FE produced in average heavier grains than Vitron. However, when considering individual grains there were, in general, no differences in GW. Therefore, the negative relationship between average grain weight and FE would not be constitutive, and would mostly represent the increase in the proportion of distal grains within the spikelets or of grains from apical spikelets as a consequence of an increased FE, reducing the average size of the grain but mostly unaffecting the size of particular grains. This provides further and stronger support to the idea of using FE as a criterion to further raise yield potential in wheat breeding programmes.

Rice panicles are composed of many branches with two types of extreme grains, the superior and the inferior. Traditionally, it has been well accepted that earlier flowers result in superior grains and late flowers generate inferior grains. However, these correlations have never been strictly examined in practice. In order to determine the accurate relationship between superior and inferior grains and the flowering order, we localized all the seeds in a panicle in four distinct rice species and systematically documented the rice flowering order, flower locations and the final grain weight for their relationships. Our results demonstrated that the grain weight is more heavily determined by the position of the seeds than by the flowering order. Despite earlier flowering has a positive correlation with the grain weight in general, grains from flowers blooming on the second day after anthesis generally gained the highest weight. This suggests earlier flowers may not result in superior grains. Therefore, we concluded that superior and inferior grains, commonly determined by grain weight, are not fully correlated with the flowering order in rice. Following the order of the grain weight, the superior grains are generally localized at the middle parts of the primary branches, whereas inferior grains were mainly on the last two secondary branches of the lower half part of the panicle. In addition, the weight of inferior grains were affected by spikelet thinning and spraying with exogenous plant growth regulators, indicating that physiological incompetence might be the major reason for the occurrence of the inferior grains.

Effects on the quality properties in real storage conditions and galvanized steel silos for wheat varieties (cv. Bezostaya and Lancer) in the 180 day storage period were investigated. The wheat quality properties including grain moisture, crude protein, hectoliter weight, thousand grain weight, Zeleny sedimentation, wet gluten, dry gluten, and falling number were monitored in the laboratory in three replicates at regular intervals. From these results, crude protein, hectoliter weight, and thousand grain weight of Bezostaya and Lancer wheat varieties decreased with an increase in storage period. Grain moisture, Zeleny sedimentation, wet gluten, and dry gluten increased with storage period until the first two months and subsequently decreased. However, grain moisture for Lancer wheat increased until the third month of storage, after which it decreased. Falling number increased with increase in storage period.

The cellular expansion of maternal tissues has been suggested as strongly associated to grain volume determination in wheat and is therefore a key process to understand potential grain weight determination. The dynamics of grain growth in seed size-contrasting diploid, tetraploid and hexaploid genotypes of wheat were evaluated to explore the relationships between the final grain weight and: a) grain volume, b) water content, c) epidermal pericarp cell size and d) the rate of cell area (area per cell) increase. The assessment of cell expansion was reinforced by the study of the expression of the XTH5 gene in pericarp tissues, as this gene codifies a cell wall-remodeling agent. Differences in grain weight across ploidies and experiments (greenhouse and field evaluations) were attributable to the grain-filling rate (ANOVA p

The maize weevil ( Sitophilus zeamais ) is a significant pest of stored maize grain in tropical and subtropical regions worldwide. As a further step towards finding maize genotypes with acceptable levels of resistance to the maize weevil, 53 experimental maize hybrids that were generated in a North Carolina design II mating scheme, were evaluated for grain weight loss due to maize weevil damage under ambient temperature and humidity (ATH) conditions, in the on-station stock room at Harare, Zimbabwe. The study indicated that genotypic variation for grain weevil resistance was large (19%–57%) after five months of infestation by the maize weevils. A few F 2 populations with potential for use as sources of breeding new varieties for maize weevil resistance were identified. They displayed consistency of high performance (better than the standard control varieties) and showed a lower rate of grain weight loss due to the maize weevils over the five months in the stock room. The male and female GCA and SCA effects were highly significant ( P ≤ 0.01) for maize weevil resistance, especially at two months after infestation, indicating that resistance was controlled by genes with both additive and non-additive effects, respectively. Further, the distribution of grain weight loss data for the hybrids was continuous and almost normal at the four intervals of data collection, clearly supporting that resistance was partial and possibly conditioned by minor genes with cumulative effects. Therefore, resistance could probably be improved by selection among the promising F 2 populations identified in this study. Although resistance was partial, a plot of grain weight loss of hybrids from the different categories demonstrated the advantage to farmers for growing a resistant variety (low percentage loss over time) compared to the susceptible ones that incurred significant grain weight losses. However, grain weight loss data were not significantly correlated with yield ( r = 0.14; P > 0.05), suggesting that the traits are not mutually exclusive. Therefore, breeding for maize weevil resistance in these populations would not necessarily compromise grain yield. Our results demonstrate that there is potential in developing maize varieties with acceptable levels of maize weevil resistance through recurrent selection procedures which exploit both GCA and SCA effects with sustainable impact on food security and the environment.

Low phytic acid (lpa) crop is considered as an effective strategy to improve crop nutrition. However, the inferior agronomic performance of lpa crops and their environmental growth adaptation have not yet been fully understood. Three rice lpa lines and their corresponding wild-types were used to compare their differences in grain phytic acid (PA) in response to high temperature (HT) and its relation to spikelet sterility and grain weight at a controlled temperature at the filling stage. Results showed that HT caused an increase in grain PA and inorganic phosphate contents, with more substantial increase of PA content for lpa lines compared with corresponding wild-types. This increase in PA content in high temperature-ripened grains was not simply attributed to the reduction in grain weight and relatively enhanced proportion of aleurone-layer fraction to whole grains. Significant increase in PA contents was also detected in milled rice. Moreover, spikelet sterility and grain plumpness of lpa lines were more susceptible to HT stress than those of wild-types. Exogenous PA spraying with an appropriate concentration could increase grain PA content, but it had only a slight contribution to the enhancement of heat-tolerance and injury alleviation for rice exposed to stressful HT.

Functional, physico-chemical properties and FTIR analysis of flours and starches of two African rice cultivars (Transgressive Segregants TGS 3 and TGS 25) were investigated. The TGS 3 showed higher 1000 kernel grain weight (29.55 g), dockage (1.00 g), immature grain (1.97 g), thickness (2.10 mm), chalkiness (11.17%) and damaged grain (0.70%). However, the TGS 25 showed higher head rice yield (51.11%), milling degree (9.60%), length (6.88 mm) and elongation ratio (3.64). Also, the TGS 25 showed higher alkaline spread value (6.67), amylose content (30.81%), uncooked (7.15 mm) and cooked (10.17 mm) rice length. The WAC (2.77 g/mL) and OAC (1.08 g/mL) of TGS 25 flours were higher than TGS 3. The L value of TGS 25 flour (92.13) and starch (97.88) were higher than those of TGS 3. The TGS 3 flour and starch showed higher peak, breakdown and peak times of 4308 and 3531 cP, 2200 and 1947 cP, 5.43 and 4.60 min, respectively. The TGS 25 (85.67 ° C) starch showed significantly higher boiling point than the TGS 3 (81.33 ° C). Pasting temperatures of TGS 3 and TGS 25 starches were 78.65 and 78.75 °C, respectively. Cyclodextrin (A and B) and L (−) glucose were detected in the starch and flour of TGS 25 but were present in TGS 3 starch but absent in its flour.

Experiments were conducted to evaluate the performance of hermetic triple bagging using Purdue Improved Crop Storage (PICS) bags for storage of Bambara groundnut ( Vigna subterranea (L.) Verdc.). One set of experiments used grain heavily infested by Callosobruchus maculatus (F.) while a second set began with a low level infestation. Each experiment consisted of V. subterranea grain kept in four replicate 50 kg PICS bags or two replicate woven bags as controls. Two to five days after the beginning of the experiments, oxygen level inside the bags averaged about 21% (v/v) in the controls but decreased significantly in PICS bags, reaching 10% (v/v) with the heavily infested grain but falling only slightly in the lightly infested grain. After 7 months of storage, (i) the number of C. maculatus adults found between and within the grains, (ii) the 100 seed weight, (iii) the number of seed with holes, and (iv) the percentage germination of grain stored in PICS bags did not differ from what had been measured on the day that the experiment was set up. In woven bags, by contrast, there was a massive increase in C. maculatus numbers with means of 309 and 251 adults per 500 g in heavily and lightly infested grain, respectively. Grain weight losses in the woven bag controls ranged from 8 to 19% and the percentage of C. maculatus emergence holes per 100 seed increased from 51 to 135%.

Two-year field examinations to see effects of the principle components of a fungus causing “fairy rings” phenomena on lawns, 2-azahypoxanthine (AHX) and imidazole-4-carboxamide (ICA), on wheat were performed. The treatment of AHX or ICA was performed, in the early (seedling treatment, seed soaking treatment) and late (field treatment) developmental stages, and the resulting number of ears and grain weight per plant increased. AHX treatment increased the number of ears before tillering and ICA treatment increased the number after tillering. The high temperature during tillering stage in 2011 was a stress condition for wheat production in fields. The results indicated that AHX and ICA increased number of tillers and then number of ears, resulting in the increase of the grain yield even though under high-temperature stress.

Molecular design breeding is one of straightforward approaches to break yield barriers in rice. In this study, GW6 gene for grain length and width from Baodali was transferred into an indica recurrent parent 9311 and a japonica variety Zhonghua 11 (ZH11) using marker-assisted backcross (MAB). One and three introgression lines were selected for phenotypic analysis from 9311 and ZH11 genetic backgrounds, respectively. SSL-1, an improved 9311 near isogenic line with GW6 performed 11%, 19% and 6.7% higher of grain length, 1000-grain weight and single plant yield, respectively, as compared with 9311. All the three improved ZH11-GW6 lines, R1, R2 and R3, had more than 30% increase in grain weight and about 7% higher in grain yield. Seed plumpness of R1, R2 and R3 was improved synchronously because the three ZH11-GW6 lines contained GIF1 (Grain Incomplete Filling 1), a dominant grain filling gene. Thus, GW6 has high potential in increasing the yield of inbred lines through MAB, making it an important genetic resource in super hybrid rice breeding. This study provides insights in the utilization of GW6 for large grain and high yield rice breeding via molecular design breeding.

Poor biomass production in wheat ( Triticum aestivum L.) under rainfed condition is a serious concern world-wide. Micro-watershed could be an effective approach in increasing wheat biomass production in rainfed conditions. Bread wheat (cv. Haider-2000) was field tested in five micro-watersheds, established under rainfed conditions at the Cereal Crops Research Institute Pirsabaq, Khyber Pakhtunkhwa, Pakistan. The experiment was conducted in randomized complete block design with six replicates during 2003–04 and 2004–05. Five micro-watersheds about 0.45–0.5 m above ground level were: (i) transparent plastic sheets, (ii) stones, (iii) compacted soil, (iv) loose soil, and (v) control (no micro-watershed). Micro-watershed and year significantly affected tillers m −2 , days to maturity, leaf area tiller −1 (LA), leaf area index (LAI), and biomass production whereas 1000 grain weight was significantly affected by only micro-watershed. Maximum tillers m −2 (249.8), LA plant −1 (18.48 cm 2 ), LAI (0.153), thousand grain weight (37.2 g) and biomass yield (8105 kg ha −1 ) were recorded from micro-watershed covered with stones. Micro-watershed covered with stones had increased biomass and grain weight by 9 and 11% respectively over control. Micro-watershed significantly reduced days to maturity. Adequate as well as appropriately distributed rainfall in the second year caused to produce more tillers m −2 (8.5%), LA (13.2%), LAI (22.9%), biomass (7.4%) and delayed maturity by 8.5 days over first year. It can be concluded that micro-watershed covered with stones was better than other treatments.