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Leaf rolling (LR) is one of the defensive mechanisms that plants have developed against adverse environmental conditions. LR is a typical drought response, promoting drought resistance in various gramineae species, including wheat, maize, and rice. Rice cultivation faces the formidable challenge of water deprivation because of its high water requirements, which leads to drought-related symptoms in rice. LR is an important morphological characteristic that plays a key role in controlling water loss during water insufficiency, thereby regulating leaf area and stature, which are crucial agronomic traits determining yield criteria. Bulliform, sclerenchyma, mesophyll, and vascular bundles are the cells that engage in LR and commonly exhibit adaxial or abaxial types of rolling in rice. The specific genes linked to rolling, either adaxially or abaxially, are discussed here. In addition to the factors influencing LR, here is a short review of the morphological, physiological and molecular responses of this adaptation under drought stress. Moreover, this review highlights how LR combats the consequences of drought stress. The eco-physiological and molecular mechanisms underlying this morphological adaptation in rice should be further explored, as they might be useful in dealing with various degrees of drought tolerance. [ABSTRACT FROM AUTHOR]

In planta haploid embryo induction is a powerful plant breeding tool, but is limited to very few crops. Two recent studies by Wang et al. and Lv et al. report seed-based haploid systems that produce paternal haploid embryos by engineering CENTROMERIC HISTONE H3 (CENH3). Together with recent translation of maize maternal haploid induction ability into wheat and rice, this extends our collection of haploid inducer lines. [ABSTRACT FROM AUTHOR]

Abstract India is an agrarian country generating surplus amounts of paddy, wheat, and maize crop residues at large scale, which are not being managed properly. The anaerobic digestion is an efficient way of managing these residues in an environmentally friendly manner. It results in high calorific methane gas and fertile rich digestate. The current study focused on reviewing the availability, methane potential and technological developments to improve the methane production of crop residues. The methane potential from the anaerobic digestion of surplus paddy, wheat, and maize residues in India is estimated as 18,677 Mm3/year (632 × 109 MJ/year). The methane potential of crop residues could substitute 52 Mt/year of coal utilisation that evades 46 Mt/year of net CO 2 emissions from releasing into the atmosphere. Highlights • Technological developments in anaerobic digestion of crop residues are discussed. • Co-digestion of crop residues with nitrogen rich substrates improves the efficiency. • Pre-treatment methods and recirculation digestate improves the efficiency. • Anaerobic digestion of crop residues had net energy potential of 632 × 109 MJ/year. [ABSTRACT FROM AUTHOR]

Development of semi-dwarf wheat (Triticum aestivum) and rice (Oryza sativa) led to increased yields and agronomic efficiencies with less lodging. While these short-stature cereals have become common in global crop production, commercial maize (Zea mays L.) hybrids remain tall. There is no information currently available on plant N uptake or yield responses to N timing for short stature maize hybrids. We tested three hypotheses on short-stature and tall maize hybrids 1) short-stature maize hybrids would have similar yield response to in-season N application compared to tall hybrids, 2) short-stature maize hybrids would have similar dry matter and N uptake patterns to tall hybrids, and 3) there would be significant partitioning differences between short-stature and tall hybrids in dry matter and N within the plants at multiple growth stages. In ten side-by-side field trials across eight site-years in the Midwestern USA, we tested the yield response and underlying nitrogen physiology of short-stature maize hybrids and tall comparators to split-rate N application. We show that split-rate application of 50% of the total N at mid-vegetative stages (V6) averaged 0.24 t ha−1 more grain yield across 10 field trials (positive yield response in 6 out of 10 trials) compared to a single 100% up-front N application, with the same pattern for short-stature and tall hybrids. In both hybrid statures, V6 N applications showed more frequent improvement in grain yield than V12 N applications. Total N uptake at maturity was not different between short-stature hybrids and their tall counterparts (p = 0.62). N partitioning differed between short-stature and tall hybrids; leaves in short-stature hybrids had 5% higher N concentration and 13% more N content in early vegetative development, stalks had 18–27% less dry matter and 5–25% less N content, depending on growth stage, while R1 ears averaged 18% more dry matter and N accumulation (p < 0.10 in all cases). At maturity short-stature hybrids had 4% higher harvest index and 3% higher N harvest index (p < 0.10). Based on these results, we expect that N management recommendations in short-stature maize hybrids would be similar to their tall counterparts, but that short stature mitigates logistical risk by providing more flexibility for in-season N applications. This study provides a unique, robust dataset on yield and physiological response to split-rate N treatments in commercially relevant maize hybrids. • Short stature in maize simplifies in-season N application and later crop management. • Split-rate N applications at V6 increased hybrid yields 60% of the time, with similar patterns for short-stature and tall hybrids. • Overall, short-stature maize yielded similarly to tall comparators. • Short stature led to greater partitioning of N and dry matter to the grain than tall hybrids. • Greater flexibility for in-season N fertilization in short-stature maize reduces in-season application risks. [ABSTRACT FROM AUTHOR]

This study provides statistical emulators of crop yields based on global gridded crop model simulations from the Inter-Sectoral Impact Model Intercomparison Project Fast Track project. The ensemble of simulations is used to build a panel of annual crop yields from five crop models and corresponding monthly summer weather variables for over a century at the grid cell level globally. This dataset is then used to estimate, for each crop and gridded crop model, the statistical relationship between yields, temperature, precipitation and carbon dioxide. This study considers a new functional form to better capture the non-linear response of yields to weather, especially for extreme temperature and precipitation events, and now accounts for the effect of soil type. In- and out-of-sample validations show that the statistical emulators are able to replicate spatial patterns of yields crop levels and changes overtime projected by crop models reasonably well, although the accuracy of the emulators varies by model and by region. This study therefore provides a reliable and accessible alternative to global gridded crop yield models. By emulating crop yields for several models using parsimonious equations, the tools provide a computationally efficient method to account for uncertainty in climate change impact assessments. [ABSTRACT FROM AUTHOR]

Intensive rice (Oryza sativa)-based cropping systems in south Asia provide much of the calorie and protein requirements of low to middle-income rural and urban populations. Intensive tillage practices demand more resources, damage soil quality, and reduce crop yields and profit margins. Crop diversification along with conservation agriculture (CA)-based management practices may reduce external input use, improve resource-use efficiency, and increase the productivity and profitability of intensive cropping systems. A field study was conducted on loamy soil in a sub-tropical climate in northern Bangladesh to evaluate the effects of three tillage options and six rice-based cropping sequences on grain, calorie, and protein yields and gross margins (GM) for different crops and cropping sequences. The three tillage options were: (1) conservation agriculture (CA) with all crops in sequences untilled, (2) alternating tillage (AT) with the monsoon season rice crop tilled but winter season crops untilled, and (3) conventional tillage (CT) with all crops in sequences tilled. The six cropping sequences were: rice-rice (R-R), rice-mung bean (Vigna radiata) (R-MB), rice-wheat (Triticum aestivum) (R-W), rice-maize (Zea mays) (R-M), rice-wheat-mung bean (R-W-MB), and rice-maize-mung bean (R-M-MB). Over three years of experimentation, the average monsoon rice yield was 8% lower for CA than CT, but the average winter crops yield was 13% higher for CA than CT. Systems rice equivalent yield (SREY) and systems calorie and protein yields were about 5%, 3% and 6%, respectively, higher under CA than CT; additionally, AT added approximately 1% more to these benefits. The systems productivity gain under CA and AT resulted in higher GM by 16% while reducing the labor and total production cost under CA than CT. The R-M rotation had higher SREY, calorie, protein yields, and GM by 24%, 26%, 66%, and 148%, respectively, than the predominantly practiced R-R rotation. The R-W-MB rotation had the highest SREY (30%) and second highest (118%) GM. Considering the combined effect of tillage and cropping system, CA with R-M rotation showed superior performance in terms of SREY, protein yield, and GM. The distribution of labor use and GM across rotations was grouped into four categories: R-W in low-low (low labor use and low GM), R-M in low-high (low labor use and high GM), R-W-MB and R-M-MB in high-high (high labor use and high GM) and R-R and R-MB in high-low (high labor use and low GM). In conclusion, CA performed better than CT in different winter crops and cropping systems but not in monsoon rice. Our results demonstrate the multiple benefits of partial and full CA-based tillage practices employed with appropriate crop diversification to achieve sustainable food security with greater calorie and protein intake while maximizing farm profitability of intensive rice-based rotational systems. • Rice-maize (R-M) outperformed over all other rice-based cropping systems considering yields and profits. • Conservation agriculture (CA) and alternate tillage (AT) outperformed than conventional tillage (CT). • R-M and rice-wheat-mungbean systems are more beneficial when layered with CA and AT. • Rice-rice system is more labor intensive and less profitable than other systems. • CA is good for winter crops and for cropping systems but not for rice but AT can be viable alternative option. [ABSTRACT FROM AUTHOR]

Yield-scaled nitrous oxide (N 2 O) emission (YSNE) has been recognized as a means for developing appropriate nitrogen (N) management strategies to balance food security and mitigating N 2 O emissions. To better understand and use the concept of YSNE, it is essential to be assessed under various field conditions. The main objectives of this study were to assess the relationship between N inputs and YSNE with published results and identify response patterns of YSNE to N inputs. We assessed the relationship between N inputs and YSNE using published results encompassing 1800 observations (published from 1980 to 2020) from maize, rice, and wheat crops worldwide. Background yield-scaled N 2 O emission (BYSNE; a YSNE in the condition of zero N input) was significantly different by crop type. Rice (90.8 ± 12.9 g N 2 O−N Mg−1) had lower BYSNE compared to maize (174.2 ± 30.1 g N 2 O−N Mg−1) and wheat (325.4 ± 41.8 g N 2 O−N Mg−1). BYSNE was positively correlated with annual mean temperature in maize, rice, and wheat fields. BYSNE was negatively correlated with soil total nitrogen contents in rice fields. Over 60% data set showed a positive relationship between N inputs and YSNE in all three crops studied. A small proportion of the dataset had an optimum N rate that minimized YSNE. The results suggest that in general, lower N input rates result in lower YSNE in crop production. YSNE can be reduced in three ways: increasing yields (Type 1), reducing N 2 O emissions (Type 2), and both increasing yields and reducing N 2 O emissions (Type 3). To identify appropriate measures, we suggest a N 2 O emission-yield curve combining responses of yields and N 2 O emissions to N inputs. In type 1, 2, and 3 measures, an N 2 O emission-yield curve is shifted to the right, down, and both right and down, respectively. Through identifying direction and magnitude of the shifting, the effects of applied measures on yields and N 2 O emission in N input levels can be easily compared and recognized. This study provided insights into the nature of YSNE and how YSNE responds to N inputs. It also suggested an N 2 O emission-yield curve, which can be useful to identify how certain measures affect both N 2 O emissions and crop yields. The information can be useful for scientific community and policymakers developing appropriate N management strategies to balance food security and the mitigation of N 2 O emissions. [Display omitted] • Background yield-scaled N 2 O emission (BYSNE) varied by crop type. • BYSNE was positively correlated with annual mean temperature. • Over 60% data sets showed consistently lower yield-scaled N 2 O emission as N input decreased. • N 2 O emission yield curve showed the effects of mitigation measures on both yields and N 2 O emission. [ABSTRACT FROM AUTHOR]

• Techno-economic model and analysis of bifacial agrivoltaics (AV) with paddy rice. • Performance indicator of AV is economics driven—not land equivalent ratio (LER) • Horizontal E/W AV layout has more economic gain than tilted N/S and vertical E/W. • Net profit from AVs will be 22–115 times higher than conventional rice cultivation. • AV with bifacial vs. monofacial panels can boost profit by around 18 to 35% Agrivoltaics (AV) promises sustainable food and energy production from shared lands. While various literature studies AVs for leafy crops, there are limited equivalent works on AVs with major crops (e.g., rice, corn, wheat, etc.). Here, we present an end-to-end modeling framework to analyze location-specific AVs over paddy rice. We consider the local ambient conditions to find the spatially distributed rice production under panel arrays, the panel yield, and the economic aspects (costs, revenue, and profit) of the AV system. On a given land, solar energy has a far larger absolute profit than rice cultivation due to the 100s of folds higher investment possible in panels compared to paddy rice. Policy-level constraints are required to set a permissible reduction in rice for more energy. We find that, while maintaining 90% (or 80%) of the conventional rice production, the overall profit can be 22–115 (or 30–132) times higher than rice cultivation. [ABSTRACT FROM AUTHOR]

The food chain is responsible for harmful chemical poisoning due to land pollution. Heavy metal contamination of the food chain is regarded as one of the key environmental channels of human exposure leading to possible health risks. The purpose of this study was to investigate the toxic elements of soil samples of different cropped fields of the specific parts on the lower course of the river Indus in district Jamshoro, the southern Sindh province of Pakistan. We report the comparative elemental composition of the Soil at 3 and 6 in. depth of the wheat, rice, corn, and okra cropped field using Laser-Induced Breakdown Spectroscopy (LIBS). Soil plasma is generated using Q-Switched Nd: YAG laser (1064 nm), 5 ns pulse duration, and 10 Hz repetition rate. At laser energy of 25 mJ the estimated irradiance is 7.15 × 1010 W/cm2. In this experimentation we have detected the Fe, Si, Mg, Ca, Al, Ba, Hg, Cr, Ni, Mn, H, Cu, Li, Sr, K, Ti, Na, Pb, V, and C in soil plasma spectra at the depth of 3 in. and 6 in. of wheat, rice, corn, and okra cropped field. We have estimated the electron temperature and electron number density under the assumption of the local thermodynamic equilibrium. We have found electron temperature (T e) corn plasma (3 in. depth) in the range of (13768–7003) K and electron number density (N e) in the range of (9.01–5.18) × 1016 cm−3. In addition, we have also estimated the weight percentage of the different soil samples using Calibration Free LIBS (CF–LIBS). • The Laser-Induced Breakdown Spectroscopy technique was used for the analysis of soil-cropped plasma. • Recombination rate of soil-cropped plasma. • Detection of heavy metals in soil cropped field. • Soil plasma parameters such as electron temperature and electron number density. • A singly ionic calcium line was used to calculate electron number density. [ABSTRACT FROM AUTHOR]

Even though China has increased grain output in the past decade and greatly contributed to reducing global hunger, the country is still confronted with intense food security pressure due to its huge population base and severe loss of farmland. It has become increasingly important to fully exploit yield gaps (the difference between potential and actual yields) of all staple grains and to identify priority areas in order to achieve the UN sustainable development goal of zero hunger by 2030. The objective of this study was to calculate the production and yield gaps for rice (Oryza sativa L.), wheat (Triticum aestivum L.), and corn (Zea mays L.) across 31 provinces of mainland China, and then to propose sustainable ways to exploit the production and yield gaps in relation to the availability of natural resources and the ecological conditions of the various regions. The yield potential was estimated by assuming that certificated cultivars were adopted in each agricultural ecological zone (AEZ) and that state-of-the-art technologies and best management practices were used. The results suggested that the gross potential productivity of the three staple grains of mainland China in 2016 was 8.86 × 108 tons, with a production gap of 2.99 × 108 tons. Corn exhibited the greatest yield gap. The highest potential productivity was observed in the Northeast Plain and the Huang-Huai-Hai/North China Plain, accounting for 26.35% and 35.91% of the country's total potential productivity, respectively. The greatest yield gaps were also found in these two plains. To narrow yield gaps, farmland infrastructure, especially irrigation facilities, should be improved, and field management should be strengthened for the provinces with the greatest gaps. However, in view of natural resource constraints (e.g., water shortages in Northern China), water-saving measures and techniques have been encouraged throughout mainland China and the planting of high water-consuming crops such as rice has been discouraged and should be reduced and replaced by other crops in the North China Plain and Northwest China. Using presently available cultivars and field management technologies, China still has great potential to increase grain production and improve food security by closing exploitable yield gaps through the use of suitable production methods based on existing natural resource capacity and ecological status. • To assess achievable potential productivity at present technology using a combined method of AEZ and certificated cultivars. • To analyze the space for the increase of food production, which provide decision basis for closing the yield gaps. • To put forward sustainable approaches to close yield gaps by considering natural resource and environmental restraints. [ABSTRACT FROM AUTHOR]

Grain crops are an important part of the human diet, accounting for a third of the consumed calories. Throughout human history, annual grain crops with high yields have been obtained through domestication. However, the "annual" characteristic brings associated a series of economic and environmental disadvantages, such as soil erosion or low soil resources use, that can be solved if the agriculture of annual varieties evolves towards perenniality. For this reason, there are numerous research groups dedicated to study and obtain perennial varieties of the most cultivated grain crops. In this review article, we have summarized the most important advances related to the subject, focusing on the domestication and hybridization of the most productive grains globally: wheat, rice, maize, rye and sorghum. We highlight their benefits for sustainable agriculture worldwide due to perennial grains may contribute to reducing erosion, acting avoiding carbon losses, reducing nutrient losses to waters or capturing nutrients deeper in soil when they are scarce, reducing farm costs and thus, increasing the effectiveness of agricultural grain crops. Despite perennial grain crops having disadvantages, they possess outstanding characteristics which make them resilient crops to deal with the imminent climate change. However, maintaining the perenniality trait without reducing genetic biodiversity is a great challenge of current scientific importance that must be deeply considered. • Grain crops constitute an important part of the human diet. • Perennial grain crops can reduce environmental problems associated with annual crops. • There are breeding programs to breed perennial varieties of wheat, rice and maize. • The first perennial grain cultivars, such as Kernza, are being introduced in the market. [ABSTRACT FROM AUTHOR]

Abstract: Leaf rolling is known as a typical response to water deficit in numerous species such as rice, maize, wheat and sorghum. However, it results not only from the water deficit but also from other abiotic stress factors such as salt, temperature, heavy metals and UV radiation. In addition to the abiotic factors, herbivores, viruses, bacteria and fungi are biotic factors of leaf rolling. Leaf rolling is an effective protective mechanism from the effects of high light levels in agricultural fields and protects leaves of unirrigated plants from photodamage. The rolling reduces effective leaf area and transpiration, and thus is a potentially useful drought avoidance mechanism in dry areas. The current review focuses on the recent progress in understanding leaf rolling in relation to abiotic and biotic stress factors, the role of signal molecules, and the mechanisms of gene regulation. [Copyright &y& Elsevier]

The insect growth regulator methoprene was evaluated for control of Liposcelis bostrychophila Badonnel, Liposcelis decolor (Pearman), Liposcelis entomophila (Enderlein), Liposcelis paeta Pearman (Psocoptera: Liposcelididae), and Lepinotus reticulatus Enderlein (Trogiidae) at application rates of 1, 5, and 10 ppm on maize, wheat, and rice. Methoprene did not completely suppress progeny production during the 40-day test period, but did cause a significant reduction in adult progeny in all psocid species at the application rates of 5 and 10 ppm. At 1 ppm, numbers of adults were reduced for all species on wheat and maize, but only for L. paeta on rice. Nevertheless, the numbers of nymphs present after 40 days generally were not reduced, relative to the controls. Methoprene applied at rates of 1 to 10 ppm to stored grain would not provide adequate control of psocids. [ABSTRACT FROM AUTHOR]

Abstract: The influence of earthworms on nematodes and protozoan communities was determined during the wheat phase of a six year rice–wheat rotation agro-ecosystem. Experimental plots in the rotation had five treatments, i.e. incorporation or mulching of maize residues with or without added earthworms and a control. The addition of maize residues to soil strongly affected the abundance and community structure of nematodes and protozoa in the absence of earthworms. The presence of earthworms gave significantly lower total nematode numbers at all soil depths following maize residue incorporation than the same treatment without earthworms, and also gave lower (although not significantly) total nematode numbers in the upper soil layer following maize residue mulching than the same treatment without earthworms. This was mainly due to a significant decrease in bacterial-feeding nematode numbers. Earthworms also strongly affected the distribution of the number of total nematodes and two trophic groups (bacterial and plant feeders) with soil depth. In the presence of earthworms, total protozoan and flagellate numbers significantly increased at all soil depths following both incorporation and mulching of maize residues, while numbers of amoebae increased only when maize residues were mulched. Additionally, in earthworm casts total nematode numbers (mainly bacterial and fungal feeders) were significantly higher, whereas total protozoa numbers (mainly flagellates and amoebae) were significantly lower than that in soil from 0 to 5cm layer. These results indicated that earthworm activity could affect the abundance and community structure of microfauna, and change their distribution between soil layers and cast material, depending on the mode of application of organic residues. [Copyright &y& Elsevier]

Abstract: Biomass from herbaceous crops is the largest renewable source for the production of bioproducts and biofuels. The available information about lignins in straw of herbaceous crops is scattered and the available reviews generally address wood lignins. This review is focused on the structural characteristics and separation of lignin in the straws of corn, wheat, rice and flax, and it is the first attempt to generalize the information about lignin structure of important herbaceous crops and processes for the separation of lignin from hemicellulose and cellulose in lignocellulosic crop residues. The differences in lignin structures and processes for the fractionation of the major components of straw are highlighted, and the conversion of lignin into value-added products is addressed. [Copyright &y& Elsevier]

Abstract: Mycotoxin contamination in rice is usually lower as in wheat or corn. However, there are some reports that rice has been contaminated with mycotoxins such as aflatoxin B1, B2, G1, G2 (AFS), citrinin, deoxynivalenol (DON), fumonisin B1, B2, B3 (FMS), fusarenon-X (Fus.-X), nivalenol (NIV), ochratoxin A (OTA), sterigmatocystin (STE), and zearalenone. Rice in Japan is preserved in warehouses where moisture content and temperature are regulated. Therefore, mycotoxin contamination from post harvest fungal growth occurs very seldom. Trichothecenes, aflatoxins, and STE in rice were recently analyzed in our laboratory. In 1998, a typhoon struck before rice harvesting in Japan, and the unpolished rice was found to be stained brown. Samples were collected and analyzed for the presence of trichothecenes. Mycotoxins DON, Fus.-X, and NIV were detected and confirmed with GC-MS. The quantity of trichothecenes was determined using GC-ECD. STE is a carcinogenic mycotoxin produced by Aspergillus versicolor and some other fungi. STE contamination of rice was studied in our laboratory since 1973. GC-MS, LC-MS, LC-MS/MS, and LC-UV methods for STE determination were examined, giving good results for the LC-UV method using a photo diode array detector. Different techniques for the extraction of STE from rice were also studied. Finally, brown rice was ground, and the ground rice was extracted with acetonitrile-water. An Autoprep MF-A 1000 column was used to clean up AFS and STE. The cleaned-up extract was analyzed with HPLC-UV. Forty-eight brown rice samples were analyzed, and none of them were contaminated with STE. These rice samples were also analyzed for AFS and FMS, and none of the samples were contaminated. The Ministry of Agriculture, Forestry and Fisheries in Japan is making the appropriate Institutes develop analytical methods for mycotoxins and survey mycotoxin contamination on rice as well as wheat, corn, and some other cereals. [Copyright &y& Elsevier]

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Abstract: A perfusion reversed-phase high-performance liquid chromatography method is proposed for the rapid and simultaneous separation of soybean and cereal (wheat, rice, and corn) proteins in complex mixtures of these vegetable proteins. The method consisted of a linear binary gradient in two steps, from 5 to 10% B in 0.42min, and from 10 to 50% B in 5.71min being mobile phase A, 0.3% (v/v) acetic acid in Milli-Q water and mobile phase B, 0.3% (v/v) acetic acid in acetonitrile. A temperature of 50°C and UV detection at 254nm were used. Samples and standards were prepared in a 25:75 acetonitrile–water mixture containing 0.3% (v/v) acetic acid. The method was successfully applied to the determination of the soybean protein content in commercial cereal-based products manufactured with binary, ternary, and quaternary soybean–cereal mixtures. Moreover, the method was also valid when samples contained, in addition, other cereals such as barley, rye, and millet and other non-vegetal sources of proteins such as milk and egg proteins. Unlike the Kjeldahl method, this method enabled the selective determination of soybean proteins in these complex mixtures being possible the detection and quantitation of up to 12.5 and 42.5g/kg, respectively, of soybean proteins (related to 0.1g of sample). [Copyright &y& Elsevier]

Simple but reliable PCR techniques were developed for the detection and identification of several food crops, including crops known to contain allergens. A single pair of oligonucleotide primers (PL-1C and PL-2D), that target the trnL region of the chloroplast tRNA gene in polymerase chain reaction (PCR) analysis, was used to amplify crop specific fragments. The specific DNA fragments were of the following sizes; 387 bp (canola), 532 bp (corn), 571 bp (potato), 584 bp (soybean), 615 bp (white and red rice), 642 bp (peanut), and 662 bp (wheat). Each amplified fragment was reliably identified using 3% agarose gel electrophoresis. The amplified fragments were cloned, sequenced, and a variable region was used to design specific sense primers for identity confirmation of some selected crops. When combined with the antisense primer PL-2D, specific fragments of 403, 397, 343, and 304 bp were amplified for peanut, wheat, soybean, and rice, respectively. These are common crops known to contain allergens. The PCR techniques described may be easily adapted for the detection of other crops and may be modified for use in multiplex PCR detection techniques, or micro-/macro-array analysis. [Copyright &y& Elsevier]

To prevent or prepare for future food shortages an understanding of the likely magnitude and distribution of future cereal yields is required. To this end, predictions of cereal yields have commonly been made, using various assumptions. However, the employed assumptions, namely, that yields tend to follow a given trend over time, have not been extensively tested. This study presents a test of the applicability of two general models to time series of maize (Zea mays L.), rice (Oryza sativa L.), and wheat (Triticum aestivum L.) yields for 188 nations to characterize past yield trends, to assess the relative importance of various trends on a global scale, and lastly, to determine what factors might be responsible for the presence of slowing yield growth and yield decline in some nations. Results showed that linear growth in yields has been the most common trend over time, occurring in more than half of all nation-crop data sets, and that growth significantly greater than 33.1 kg ha−1 yr−1 (the rate at which global cereal yields must grow to have the current per-capita production in 2050) constituted 20% of the data sets and was the most important trend in terms of global area harvested, production, and population. A trend of slowing yield growth was present in roughly one-sixth of the data sets, and the nations that this subset comprised made a small contribution to global area harvested, production, and population (less than 10%). Nation-crop data sets that showed yield growth greater than 33.1 kg ha−1 yr−1 had much greater yields than those that showed slowing yield growth, demonstrating that yield growth is not being limited by general physiological constraints to crop productivity. The results of a logistic regression procedure showed that the relative frequency of slowing yield growth and yield decline was negatively correlated to per-capita gross domestic product (GDP) for maize and wheat, and to growth in fertilizer rate for maize. In addition to GDP, latitude was negatively correlated with the relative frequency of yield decline. There were no significant predictors for rice. These results suggest that both economic and biophysical factors have played a role in limiting cereal yield growth. [Copyright &y& Elsevier]

Corn, rice, wheat and potato are the main sources of starches which differ significantly in composition, morphology, thermal, rheological and retrogradation properties. Cereal starches contain a significant quantity of phospholipids, while potato starch is rich in esterified phosphorus. Potato starch exhibits higher swelling power, solubility, paste clarity and viscosity than wheat, rice or corn starches. Morphological characteristics, such as shape and size of the starch granules, exhibit significant differences. Potato starch granules are smooth–surfaced, oval and irregular or cuboidal-shaped while corn, rice and wheat starch granules are angular, pentagonal and angular; and spherical and lenticular–shaped, respectively. Corn, rice and wheat starch granules are less smooth–surfaced than potato starch granules. Potato starch granules are largest (<110 μm) in size followed by wheat (<30 μm), corn (<25 μm) and rice (<20μm) starches. Gelatinization temperatures (To, Tp, Tc) and enthalpies of gelatinization (ΔHgel) of starches from different sources also differ significantly. Corn and rice starches generally show higher transition temperatures than wheat and potato starches while the ΔHgel values are higher for potato and wheat starches. Potato starch shows a higher tendency towards retrogradation than the cereal starches. The rheological properties, such as storage modulus (G′) and loss modulus (G″) of the starches from the different sources increase to a maximum and then drop during heating of all the starches. Potato starch shows highest peak G′, G″ and lower tan δ than corn, rice and wheat starches during the heating cycle. [Copyright &y& Elsevier]

Land use change in China is related closely to global environmental change and global food security. In this paper, we analyzed land use change for rice, wheat and maize production in China during 1961–1998 based on long-term historical data. The results indicated that the total land area planted for cereals had both increased and decreased between 1961 and 1998. The total area in cereals increased or remained unchanged during 1961–1978, a period when the “Cultural Revolution” occurred, and also increased during 1986–1990 when the Chinese government increased subsides to agriculture. However, the total area in cereals declined during 1980–1985, a period corresponding to the implementation of the “household responsibility system” policy, and during 1991–1995, when a large proportion of the rural labor force moved to urban areas. The center of cereal production has moved towards northern China although the major area planted for rice, wheat and maize together is still located in southern China. The yield per hectare for all crops has increased from 1.21 t/ha in 1961 to 4.83 t/ha in 1998, but the yield per unit chemical fertilizer use decreased from 164 (rice), 44 (wheat) and 93 (maize) kg/kg in 1961 to 10 (rice), 6 (wheat) and 9 (maize) kg/kg in 1998. The increases in yield per hectare and production per capita appear mostly due to the increased industrial energy inputs, especially the rapid increase in chemical fertilizer use after the “household responsibility system” in late 1970s. The decline of the yield per unit chemical fertilizer use appears as a result of fertilizer saturation, soil degradation, soil and water pollution, the shortage of irrigation in the north, the threat of flooding in the south, and poor and low quality land use, as well as other social, economic and technical issues. With limited reclaimed land resources remaining and a near saturation in the response of crops to fertilizers, increasing food demand from the increasing population will have to come mainly from increased land productivity that will almost certainly continue to lead to the decline of energy (e.g. fertilizer) use efficiency and continued environmental degradation. Alternatively China may begin to import large amounts of food. This situation will generate adverse effects on sustainable development in China, as well as food security in the world, especially if world energy is in short supply. [Copyright &y& Elsevier]

• LAI can explain 41%−64% T/ET variation;. • WUE c was mainly controlled by climatic factors (i.e., T a , VPD, R n , T s);. • WUE e was jointly controlled by LAI and climatic factors (T a , EF);. • LAI exerted stronger controls on WUE e than climatic factors by regulating T/ET. • Carbon uptake regulated WUE e more, while water consumption controlled WUE c. Understanding the interactive responses of agroecosystem water use efficiency (WUE) to climatic and vegetation factors is significant for revealing how ecohydrological processes vary between the carbon and water cycles in the changing climate. Based on data from 11 eddy covariance flux sites for a total of 32 site-years in four typical agroecosystems, including winter wheat (Triticum aestivum L.), paddy rice (Oryza sativa L.), soybean (Glycine max L. Merr.) and summer maize (Zea mays L.), evapotranspiration (ET) of the four crops was partitioned based on the theory of underlying WUE. Seasonal dynamics of transpiration (T), ET, gross primary production (GPP), T-based WUE at the canopy level (WUE c) and ET-based WUE at the agroecosystem level (WUE e) were investigated. A series of climatic and vegetation factors affecting WUE c and WUE e were quantified using the path analysis method. T/ET was 0.67 ± 0.04 for summer maize, followed by winter wheat, soybean and paddy rice, with values of 0.65 ± 0.07, 0.60 ± 0.05 and 0.57 ± 0.02, respectively. T, ET, GPP and WUE e increased as crops grew but decreased as crops matured. However, WUE c did not change as apparently as WUE e since T and GPP changed synchronously throughout the growing season. Summer maize possessed the largest WUE c of 5.69 ± 0.29 g C kg−1 H 2 O, followed by winter wheat, soybean and paddy rice, with values of 4.47 ± 0.87, 3.79 ± 0.20 and 2.60 ± 0.17 g C kg−1 H 2 O, respectively. WUE e followed the same order as that of WUE c among the four croplands, with values of 3.32 ± 0.71, 2.73 ± 0.81, 1.90 ± 0.10 and 1.47 ± 0.09 g C kg−1 H 2 O, respectively. WUE c was mainly regulated by canopy water consumption than carbon sequestration, while carbon sequestration regulated WUE e more than water consumption at the ecosystem scale. WUE c was mainly controlled by climatic factors (vapor pressure deficit, net radiation, air temperature and soil temperature) in the croplands, while the leaf area index exerted stronger controls on WUE e variations than climatic factors by its strong regulation on T/ET in the four croplands. [ABSTRACT FROM AUTHOR]

China, as one of the largest food consumers in the world, is currently experiencing obvious impacts of climate change. Exploring the impact of climate change on the production potential of maize, wheat, and rice in China is of great significance in adapting to climate change and safeguarding global food security. In this study the Global Agro-Ecological Zone (GAEZ) model and the Extreme-Point Symmetric Mode Decomposition (ESMD) model were used to explore the trends in production potential of China's three major crops in the context of climate change from 1960 to 2010. There was a quasi-3-year and quasi-5-year cycle in changes in maize, wheat, and rice production potential due to climate change in China. Climate change increased maize and rice production potential and reduced wheat production potential. The increase in minimum temperature was the main reason for the increased maize and rice production potential. Reduced wheat production potential was mainly caused by increased maximum temperature. Decreases in precipitation had a substantial negative impact on the production potential of all three crops. These results suggest that priority should be given to adjusting the structure of agricultural cultivation and appropriately expanding the planting area of maize and rice to adapt to climate change. Accelerating the construction of agricultural infrastructure to reduce the negative impact of declining precipitation and increasing daytime temperature on agriculture is also a high priority in order to safeguard food security. • Climate change increased maize and rice production potential of China • Increased minimum temperature was the primary reason for increased yields • Wheat production potential decreased mainly because of maximum temperature stresses • There was a quasi-3&5-year cycle in changes in crop production potentials [ABSTRACT FROM AUTHOR]

• A plastic phenology model was developed for simulating crop reproductive phase. • The model assumes a dynamic response of development rate to temperature. • Wheat, rice, and maize phenology observations under varied conditions were used. • The model effectively reduced phenology simulation error in a simple and effective way. Understanding how crop development rate responds to the environment provides the basis for evaluating the impact of climate change on crop yield. In most crop simulation models, temperature response functions of development rate during the reproductive growth period (RGP) are assumed to only vary with temperature and not with other environmental factors. However, studies have indicated that the response functions may be plastic with other factors. Until now, little attention has been paid to this type of response. Here, using extensively collected field observations and data from intentionally designed interval planting experiments with winter wheat (Triticum aestivum L.), rice (Oryza sativa L.), and spring maize (Zea mays L.), we show that temperature response functions during RGP are plastic with day of year of flowering/heading (DOY R). Coefficients of determination between DOY R and development rate were significant for 69% sites. Partial correlation coefficients between development rate, temperature, and DOY R suggest that DOY R explains almost the same variability in maturity date as temperature. The plastic model was developed by coupling DOY R with a linear temperature response function. The model can improve the fitting efficiency by 112%, while dependency between DOY R and temperature explains less than 25% of this improvement. The average RMSEs of simulated maturity date estimated by the plastic model in the three crops were 2.1, 2.5, and 3.7 d, respectively, while the corresponding values given by widely applied traditional models were 3.1, 6.5, and 7.4 d, respectively. Therefore, the plastic model can reduce simulation error by half. Moreover, simulation errors resulting from the plastic model have less systematic bias than traditional models. The plastic model simply and effectively provides accurate estimates of crop maturity and reduces the system deviation of the estimates. Coupling the plastic model of crop development with crop simulation models will likely decrease uncertainties in simulated yield under warming conditions. Additionally, results of this study will encourage future studies of other phenotype plasticity considered in current crop simulation models. [ABSTRACT FROM AUTHOR]

Biochar applications to soils remain to be explored for their effect on herbivorous insects on crops. Our laboratory experiments examined the effect of three types of biochar (derived from straw of corn, Zea mays L., wheat , Triticum aestivum L., or rice, Oryza sativa L.) by four amendment rates (0, 1.5%, 3% or 5%) on reproduction of Sitobion avenae Fab. on wheat. In addition, a three-year field experiment was carried out to evaluate the role biochar application played in suppressing S. avenae populations. The laboratory experiments showed that biochar amendments decreased aphid lifetime fertility and population growth. The negative effect varied in magnitude depending on both biochar type and amendment rate, tending to be stronger both at the 5% rate than at lower rates and for corn than for rice and wheat straw-derived biochar. The field experiment did not show a consistent effect of biochar application on aphid population size across three years, while demonstrating a distinct suppressing effect in the third year after biochar application. Our results from laboratory study suggest that biochar application can impair S. avenae fertility and population growth potential, yet our field experiment provides insufficient evidence in suggestive of the decisive role biochar application plays in suppressing aphid populations. • Biochar type and amendment rate impaired aphid fertility. • Biochar type and rate inhibited aphid population growth. • The effect of biochar varied across years in wheat field. [ABSTRACT FROM AUTHOR]