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Rice is well adapted to a wide range of climates, but is highly susceptible to heat during flowering. However, there are uncertainties in assessing the occurrence of heat-induced spikelet sterility (HISS) and the impact of climate change. One reason is the gap between the ambient air temperature and the panicle temperature, which determines the magnitude of HISS in field studies. To improve our understanding of this gap, we established a multi-site monitoring network (MINCERnet) to measure canopy micrometeorology and heat stress in the major rice growing regions (Sub-Saharan Africa; South, Southeast, and East Asia; and the USA). MINCERnet assessed the processes that determine panicle temperature and the resulting HISS in open fields using the same cultivars (‘IR64’, ‘N22’, and ‘IR52’) and a standard system (MINCER) for micrometeorological monitoring under diverse climates. By using the MINCERnet data in the canopy heat-balance model (IM2PACT), we confirmed that the canopy and panicle transpiration and the resulting evaporative cooling strongly affected the gap between the ambient air temperature and the panicle temperature, and that the HISS rate in open fields could be predicted accurately in diverse climates by using the mean panicle temperature during the flowering hours. The “oasis effect” in the broad sense, that is, evaporative cooling and the increase of relative humidity, which is nested at the various levels along the continuum from the landscape to the panicle, formed temperature and relative humidity gradients along the continuum in response to different climatic conditions. The heat-balance characteristics (i.e., a stronger evaporative cooling under drier climate conditions) suggested that the risk of HISS caused by global warming will increase more in wetter climates, where panicle temperatures tended to increase. Thus, accurate relative humidity data as well as air temperature will be required, along with spatial downscaling, to permit accurate prediction of rice heat stress and yield. HISS prediction using an approach based on the panicle temperature as input for models and monitoring of canopy micrometeorology will reduce uncertainties in rice yield prediction and the response of yield to various climate change adaptation measures.

Understanding the environmental niche segregation of ammonia-oxidizing archaea (AOA) and bacteria (AOB) and its impact on their relative contributions to nitrification and nitrous oxide (N

This study is the first and unique of open-field studies to assess the determination process of heat-induced spikelet sterility (HISS) of rice by using the same variety and the same monitoring system, MINCER (Micrometeorological Instrument for Near Canopy Environment of Rice), covering the major-rice growing regions from Sub-Saharan Africa, South, Southeast, and East Asia, and USA. Applying the observation data from the monitoring network, MINCERnet, to the canopy heat balance model, IM2PACT, it was quantitatively corroborated in open-field conditions worldwide that the canopy and panicle transpiration and their evaporative cooling effect played a great role on the micrometeorological gap between the ambient air temperature and the panicle temperature, and that the sterility rate due to HISS in open-fields can be evaluated accurately in diverse climates by the mean panicle temperature at flowering hours in the flowering period. The heat balance structure suggested that the risk of HISS should be higher in high humidity climates rather than in dry climates also in the future, which lead to the importance of the humidity accuracy as well as of the air temperature in climate scenarios and their spatial downscaling for future prediction of rice heat stress and production. Applying the heat-tolerant variety was suggested to be able to keep the sterility due to HISS low in all climates. It is needed of the approach using the panicle temperature as indicator of HISS by intervening sub-model and/or monitoring of micrometeorology inside the canopy to reduce uncertainties in future rice yield prediction under various adaptation measures.

Understanding the environmental niche segregation of ammonia-oxidizing archaea (AOA) and bacteria (AOB) and its impact on their relative contributions to nitrification and nitrous oxide (N2O) production is essential for predicting N2O dynamics within an ecosystem. Here, we used ammonia oxidizer-specific inhibitors to measure the differential contributions of AOA and AOB to potential ammonia oxidization (PAO) and N2O fluxes over pH (4.0-9.0) and temperature (10-45 °C) gradients in five soils and three wetland sediments. AOA and AOB activities were differentiated using PTIO (2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide), 1-octyne, and acetylene. We used square root growth (SQRT) and macromolecular rate theory (MMRT) models to estimate cardinal temperatures and thermodynamic characteristics for AOA- and AOB-dominated PAO and N2O fluxes. We found that AOA and AOB occupied different niches for PAO, and soil temperature was the major determinant of niche specialization. SQRT and MMRT models predicted a higher optimum temperature for AOA-dominated PAO and N2O fluxes compared with those of AOB. Additionally, PAO was dominated by AOA in acidic conditions, whereas both AOA- and AOB-dominated N2O fluxes decreased with increasing pH. Consequently, net N2O fluxes (AOA and AOB) under acidic conditions were approximately one to three-fold higher than those observed in alkaline conditions. Moreover, structural equation and linear regression modeling confirmed a significant positive correlation (R2 = 0.45, p

According to Food and Agriculture Organization and Intergovernmental Panel on Climate Change reports, climate change will lead to a severe food-supply problem. In the future, food production will continually decrease because of aggravated effects of climate change, causing food production to continually decrease. Food production will be unable to satisfy the demand of the global population, leading to a food-security crisis. As the world population continues to increase, the shortage of food will become increasingly severe, particularly for those located in “climate impact hotspots” of tropical, subtropical, small-island countries, and countries that are dependent on imports to meet domestic demand such as Taiwan. Numerous Taiwanese studies have suggested that agricultural and fishery productivity has declined because of climate variation, which may cause changes and instability in food quantity and quality, and increase deficiency and uncertainty in the food supply. Therefore, to discuss the risks posed by climate change to the stability of food supply and demand, this paper, taking Taiwan as a case, explored the impact of climate variation on food security and future adaptation strategies. TaiCCAT’s supportive system for decision-making (TSSDA) was adopted here to assess and analyze the current situations of agricultural and fisheries production and supply, as well as future food supply risks, in addition to evaluating the deficiencies in the existing climate adaptation strategies in order to plan and revise feasible future adaptation alternatives. Based on the rule of risk management, the adaptation strategies recommended in this study were differentiated into two categories: proactive adaptation and planned adaptation. Proactive adaptation is emphasized to counter the uncertainty of food production, which increases the difficulty of production and necessity to import food. Conversely, planned adaptation can be used to manage the uncertainty of food supply to implement adjustments in production and marketing, as well as to mitigate the impact of climate variation.

A polyphasic approach was used to characterize a novel bacterium, designated strain TPP412T, isolated from a paddy soil in Taiwan. Strain TPP412T was Gram-stain-negative, facultatively anaerobic, rod-shaped, motile with a single polar flagellum and lacked bacteriochlorophyll. Growth was observed at 24–45 °C (optimal 25 °C), at pH 5.0–10.0 (optimal pH 7.0) and with 0–0.75 % (w/v) NaCl. Strain TPP412T showed highest 16S rRNA gene sequence similarity to members of the genera Rhodocyclus (94.1–94.5 %), Azospira (93.9–94.5 %) and Propionivibrio (93.4–94.4 %) and established a discrete taxonomic lineage in phylogenetic analysis. The major fatty acids found in strain TPP412T were C12 : 0, C12 : 0 3-OH, iso-C15 : 0 3-OH, C16 : 0, C16 : 1 ω7c/C16 : 1 ω6c and C18 : 1 ω7c/C18 : 1 ω6c. The major polar lipids consisted of phosphatidylmonomethylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and an unidentified lipid. The polyamine pattern showed a predominance of putrescine and a minor amount of spermidine. The DNA G+C content was 58.4 mol% and the predominant quinone system was ubiquinone-8 (Q-8). The low 16S rRNA gene sequence similarity values (≤94.5%) and distinct phylogenetic clustering clearly distinguished strain TPP412T from other representatives of the family Rhodocyclaceae . Based on the discrete phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence analysis, strain TPP412T is considered to represent a novel species of a new genus in the family Rhodocyclaceae , for which the name Oryzomicrobium terrae gen. nov., sp. nov. is proposed. The type strain of Oryzomicrobium terrae is TPP412T (=BCRC 80905T=JCM 30814T).

The human population is projected to grow to more than 9 billion by 2050. New farming and fishing techniques are continually being developed. However, food production remains restricted by the finiteness of natural resources and the rapid increase in the global population. In the future, food production may decline because of the aggravated effects of climate change. Food production will be unable to satisfy the demands of the global population, leading to a food security crisis. As the world population continues to increase, food shortages will become increasingly severe, particularly for regions located in “climate impact hot spots” in tropical and subtropical zones and for small-island countries such as Taiwan. In the present study, supply and demand are analysed to examine the risks and uncertainties associated with the impact of climate change on the domestic and imported seafood supply. First, we conduct a literature review to identify the climate risk for sea food security, and then, we analyse the domestic production of both the marine fishing catch and aquaculture. This study also examines the critical problems of the imported seafood supply and applies a comparative analysis of impact type and differences in the top 10 seafood import countries to organize adaptation strategies to climate change. Moreover, due to the type of climate impact and the differences between long-term climate impact and extreme climate impact, we collect and compile the existing climate adaptation strategies of fishery production, seafood importing, and the demand and supply of seafood in Taiwan. Finally, we perform a comparative analysis to seek any deficiencies in the existing climate adaptation strategies and offer new adaptation guidelines based on the existing climate adaptation strategies. The results show that Taiwan’s major adaptation strategies have been precautionary mitigation measures. In terms of resilience management, only the buffer stock scheme plan and the stabilization funds method are selected for some specific species to mitigate the short-term fluctuation in both yield and price for imported domestic seafood. However, we will confront uncertainties stemming from global climate change in the future; the existing climate adaptation strategies of Taiwan are still not sufficient to respond to climate impacts. For example, the climate change early warning system is still very inadequate, the existing scientific knowledge is insufficient, and the current adaptation strategies are insufficient for resolving the fluctuations in the market mechanism of seafood. According to the principles of risk management, the adaptation strategies recommended in this study can be differentiated into two categories: precautionary mitigation measures can be used to adapt to domestic production and uncertainties; such measures include avoidance, transfer, and reduction to prevent the frequency and consequences of climate change for building a resilient fisheries sector. Moreover, resilience management (e.g., risk retention) can be used to respond to uncertainties in supply for adjusting production and mitigating the risks of climate change.

Typical japonica type rice is sensitive to high temperature. Pon-Lai rice is a special japonica type with adaptation to the subtropical climate in Taiwan. Facing climate change, rising temperatures would damage the yield and quality of rice production. This research was conducted using Pon-Lai rice in the field of a subtropical climate. We conducted 2 experiments, including a year-round experiment and collection of samples from different districts for building different temperature conditions. We analyzed the correlation between rising temperature and rice yield or quality. In our results, the critical period of temperature effect is 0–15 days after heading (H15). The threshold of high temperature damage in yield and appearance quality was 25–27 °C. Grain weight decreased about 2–6%, while the temperature of H15 was raised 1 °C above the thresholds. Perfect grain ratio and chalky grain ratio decreased and increased, respectively, while the temperature of H15 was raised above the thresholds. However, the high temperature in H15 affected the physicochemical characteristics. In addition, we found positive correlation between grain length to width ratio and perfect grain ratio. Grain length to width ratio could be an index of temperature effects for grain quality. In our study, when the temperature was below 30 °C, a rising temperature of H15 could damage rice yield and appearance quality, and change grain shape. Our results could provide reference for dealing with the warming future in other temperate rice-cultivated countries.

Due to Taiwan's subtropical location, this study investigates the water footprint of four energy crops (corn, sweet potatoes, sugarcane and sweet sorghum), and one food crop (rice), in order to establish the water footprint data of a subtropical region. Research results indicate that sweet potatoes have the smallest water footprint, followed by sugarcane and sweet sorghum, and corn has the largest water footprint of energy crops, though the water footprint of rice is much larger, which results are consistent with the average global water footprints for these crops. The green water component accounts for more than 50% of the overall water footprint for all energy crops except of corn, indicating that the cultivation processes of these energy crops relies more on rainwater, thus, fulfilling low input selection criteria. The water footprint of rice is about 13 times larger than that of sweet potatoes and 8.8–10.4 times that of sugarcane, indicating the relative resource inefficiency of cultivating rice as a food crop. Water footprint for Taiwan-grown sugarcane, corn, and sweet potatoes compare favourably to those in the top 3 producing countries (Brazil, United States and China), as the water footprint for Taiwan-cultivated corn is only 62% of that for corn planted in the United States. A comparison of energy crop water footprints in temperate, subtropical, and tropical climate zones indicates that sugarcane cultivation is relatively more efficient in tropical and subtropical regions, due to its heavy reliance on rainwater, while corn and sweet sorghum perform better in temperate and subtropical regions.

Heat stress is an important factor that has a negative impact on rice (Oryza sativa) production. To alleviate this problem, it is necessary to extensively understand the genetic basis of heat tolerance and adaptability to heat stress in rice. Here, we report the molecular mechanism underlying heat acclimation memory that confers long-term acquired thermotolerance (LAT) in this monocot plant. Our results showed that a positive feedback loop formed by two heat-inducible genes, HEAT SHOCK PROTEIN101 (HSP101) and HEAT STRESS-ASSOCIATED 32-KD PROTEIN (HSA32), at the posttranscriptional level prolongs the effect of heat acclimation in rice seedlings. The interplay between HSP101 and HSA32 also affects basal thermotolerance of rice seeds. These findings are similar to those reported for the dicot plant Arabidopsis (Arabidopsis thaliana), suggesting a conserved function in plant heat stress response. Comparison between two rice cultivars, japonica Nipponbare and indica N22 showed opposite performance in basal thermotolerance and LAT assays. 'N22' seedlings have a higher basal thermotolerance level than cv Nipponbare and vice versa at the LAT level, indicating that these two types of thermotolerance can be decoupled. The HSP101 and HSA32 protein levels were substantially higher in cv Nipponbare than in cv N22 after a long recovery following heat acclimation treatment, at least partly explaining the difference in the LAT phenotype. Our results point out the complexity of thermotolerance diversity in rice cultivars, which may need to be taken into consideration when breeding for heat tolerance for different climate scenarios.

Several Rhodopseudomonas palustris strains have been isolated from rice paddy fields in Taiwan by combining the Winogradsky column method and molecular marker detection. These isolates were initially screened by employing seed germination and seedling vigor assays to evaluate their potential as inoculants. To fulfill the demand in the present farming system for reducing the application of chemical fertilizers, we assessed the plant growth-promoting effects of the R. palustris YSC3, YSC4, and PS3 inoculants on Brassica rapa chinensis (Chinese cabbage) cultivated under a half quantity of fertilizer. The results obtained showed that supplementation with approximately 4.0×10(6) CFU g(-1) soil of the PS3 inoculant at half the amount of fertilizer consistently produced the same plant growth potential as 100% fertility, and also increased the nitrogen use efficiency of the applied fertilizer nutrients. Furthermore, we noted that the plant growth-promotion rate elicited by PS3 was markedly higher with old seeds than with new seeds, suggesting it has the potential to boost the development of seedlings that were germinated from carry-over seeds of poor quality. These beneficial traits suggest that the PS3 isolate may serve as a potential PGPR inoculant for integrated nutrient management in agriculture.

Armillariella mellea is an edible mushroom which contains important nutritious properties including proteins, cellulose, fatty acids, and polysaccharides (PSs). PSs and sulfated polysaccharides (SPSs) were prepared and their anti-inflammatory activities were studied from cultured A. mellea . Fucose, galactose, glucose, and mannose were the major sugars of SPSs and non-SPSs. The area percentage of high-molecular-weight SPSs of 1358 kDa and low-molecular-weight SPSs of 13.4 kDa covered over half of the SPS mixture. Secretions of tumor necrosis factor (TNF-α) and interleukin (IL)-6 after lipopolysaccharide (LPS) stimulation were detected in RAW264.7 macrophages. Time-course study showed that PSs from 49-day-cultured mycelia exhibited maximal inhibition of TNF-α and IL-6 with respective values of 31.17% and 62.74%. Harvest time is an important factor to obtain bioactive PSs. SPSs exhibited more-effective inhibition of TNF-α and IL-6 secretions compared to those of non-sulfated PSs with respective values of 100% and 56.82% suppression. IκB degradation induced by LPS in macrophages was reversed by PS and SPS pretreatment. Suppression of NF-κB activation might be responsible for their anti-inflammatory effects.

A study conducted in 2006 showed that over 100 ha of rice paddies in Beitou, Taiwan, irrigated over the years using water mixed with hot spring, was heavily polluted by arsenic. Thus, the objective of the present study is to measure arsenic content in different parts of rice and paddy soils, and eventually explain the arsenic distribution in ratoon rice, including its relationship to the soil. Arsenic levels of rice in grains, straws, roots, and soils were obtained from 15 rice paddies, selected based on different arsenic soil concentrations ranging from 67 to 438 mg kg−1 (n = 15). The mean arsenic content in grains was measured at 0.20 mg kg−1 (n = 60) and the highest grain arsenic of the survey was at 1.183 mg kg−1. Meanwhile, the mean total arsenic levels were 244 mg kg−1 (n = 28) in root and 4.4 mg kg−1 (n = 28) in straw. In comparison, regression of topsoil arsenic levels with rice grains (r2 = 0.00) and straws (r2 = 0.56) were less significant compared to that with rice roots (r2 = 0.93), and the mean arsenic level in rice from root to grain was also shown to have a decreasing trend. Though concentrations of arsenic in compositive rice grain each field did not exceed food hygiene concentration limit, arsenic level in root strongly depended on arsenic concentrations of soil suggesting that the high arsenic concentration may have the potential for translocation from root to grain which ultimately effects on the human health.

Use of local leguminous manure crops as forage has become important in southern Asia because regularly producing high-quality forage legumes is difficult with the high amount of precipitation. This study evaluated whether manure soybean [Glycine max (L.) Merr.] could be used as forage and silage. Two cultivars of manure soybean were produced in two growing seasons and harvested at different growth stages. The highest forage yields were 9.3 Mg ha⁻¹ for soybean cultivar Tainan No. 4 (TN4) at stage R5 (beginning seed) and 13.0 Mg ha⁻¹ for cultivar Tainan No. 7 (TN7) at stage R7 (beginning maturity). Crude protein (CP) content was highest at R5 for TN4 and at R7 for TN7. The CP content of TN7 did not differ between spring and fall crops, but that of TN4 was 5 to 8% higher in the spring than fall. With advanced growth from R5 to R7, acid detergent fiber (ADF) content increased for TN7 but not TN4. The mean Flieg's point for silage was 26.5, 50.7, and 56.1 for ensiling treatments of soybean alone and soybean with Nilegrass (Acroceras macrum Stapf.) or corn (Zea mays L.) meal, respectively. The mean Flieg's point for silage made from soybean harvested at R3 (beginning bloom), R5 and R7 was 38.4, 47.5 and 47.3, respectively. Thus, manure soybean harvested at R5 can produce forage with high yield and good quality. The silage quality of manure soybean can be improved by ensiling with Nilegrass or corn meal.

Synthesis of heat shock proteins (HSPs) in response to heat shock (HS) is essential for thermotolerance. The effect of a Ca(2+) chelator, EGTA, was investigated before a lethal HS treatment in soybean (Glycine max) seedlings with acquired thermotolerance induced by preheating. Such seedlings became non-thermotolerant with EGTA treatment. The addition of Ca(2+), Sr(2+) or Ba(2+) to the EGTA-treated samples rescued the seedlings from death by preventing the increased cellular leakage of electrolytes, amino acids, and sugars caused by EGTA. It was confirmed that EGTA did not affect HSP accumulation and physiological functions but interfered with the recovery of HS-released Ca(2+) concentration which was required for thermotolerance. Pectin methylesterase (PME, EC 3.1.1.11), a cell wall remodelling enzyme, was activated in response to HS, and its elevated activity caused an increased level of demethylesterified pectin which was related to the recovery of the HS-released Ca(2+) concentration. Thus, the recovery of HS-released Ca(2+) in Ca(2+)-pectate reconstitution through PME activity is required for cell wall remodelling during HS in soybean which, in turn, retains plasma membrane integrity and co-ordinates with HSPs to confer thermotolerance.

This research involved a magnetic resonance imaging (MRI) technique that was applied to examine water distribution and migration in single rice kernels during the tempering process. The imaging experiments were performed in a Bruker 9.4T MRI system. Three-dimensional spin-echo (SE) imaging sequences were optimized by adjusting the scanning parameters of echo time (TE) and repetition time (TR) to obtain images with maximum contrast. The MR images showed that the moisture distribution in the rice kernel is non-uniform and compartmental. The embryo region exhibited much higher MR signal intensity than the starchy endosperm portion. The tempering process was analyzed with spatial-temporal signal intensities of the endosperm following the drying process of the rice kernel. The transient change of the signal intensities in the endosperm was well fitted with a double exponential function suggesting that both convection and diffusion contributed to the reduction of the moisture gradient within the rice kernel during tempering. This hypothesis was further supported by the experimental data of the insulated rice kernel whose convective mass transfer was excluded. The experimental results revealed that MR imaging of rice kernels could be used as an efficient tool to examine the mechanisms of moisture migration within cereal grains.

Sulfated polysaccharides (SPSs) of Antrodia cinnamomea were extracted by an exhaustive papain digestion and characterized, and their biological functions were evaluated. In this study, we demonstrated the existence of SPSs in the medicinal fungus, A. cinnamomea . Since no SPSs had previously been identified in any fungal organism, we attempted to characterize those from A. cinnamomea . SPSs from A. cinnamomea inhibited in vitro Matrigel tube formation, in an angiogenesis model, in a dose-dependent manner. Furthermore, using serum deprivation-induced apoptosis in neuronal-like PC12 cells as a stress model, the SPSs of A. cinnamomea were effective in preventing serum-deprived apoptosis. Compositional analysis revealed that myo-inositol, fucose, galactose, and glucose were the neutral sugars in SPSs of A. cinnamomea , and these SPSs had a high sulfate content. The sulfation degree paralleled their antiangiogenic and neuroprotective activities. In this work, we report novel data on the structure, antiangiogenic, and neuroprotective effects of these fungal SPSs.

The involvement of ethylene and 1-aminocyclopropane-1-carboxylic acid (ACC) in shade-induced kernel abortion at an early kernel growth stage was investigated. Changes in levels of glucose, sucrose, starch, ACC and ethylene were measured during the first 6 days after pollination (DAP) at sampling intervals of 12 or 24 h. In response to shading treatment, dry weight accumulation of apical kernels ceased within 96 h after pollination (HAP). Glucose levels in shaded kernels 12 HAP were significantly higher than in control kernels, while sucrose and starch levels were similar until 48 HAP. In the shade treatment ACC and ethylene levels increased rapidly around 24 HAP in both apical and basal kernels. When ACC was applied to ears at 32 HAP and 5 DAP, dry weight accumulation was significantly reduced only in apical kernels of 32 HAP. Significant reduction in endosperm nuclei number was also found in both shaded and ACC-treated kernels. The results of the present study suggest that ethylene may be involved in the processes leading to kernel abortion in maize. Kernels at the very early developmental stages seem to be most sensitive to ethylene.

Fomitopsis pinicola is used as a medicinal fungus in Asia. Polysaccharides extracted from 35-day-cultured fungus and its ethanolic extract showed no toxicity to endothelial cells (ECs). Extracted polysaccharides had a strong inhibitory effect on vascular endothelial growth factor (VEGF)-induced tube formation in ECs in a dose-dependent manner. Furthermore, the ethanolic extract dose-dependently suppressed production of the interferon (IFN)-γ-induced inflammation marker, IP-10. High-molecular-weight of 5367 and 1056 kDa accounted for 19.6% and 19.3% of the total polysaccharides, and a low-molecular-weight one of 14.7 kDa accounted for 53.6% of the total polysaccharides. Chemical analyses of the polysaccharides revealed that myo-inositol, fucose, galactose, glucose, mannose, and fructose were neutral sugars in the polysaccharide. Six nucleoside-type compounds including cytidine, adenosine monophosphate (AMP), adenosine diphosphate (ADP), adenosine, inosine, and thymidine were identified in the ethanolic extract. These results suggest that different extracts from F. pinicola play different roles in regulating the angiogenic process and inflammation.

Carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranol-N-methylcarbamate) and carbaryl (1-naphthyl-N-methylcarbamate) are insecticides widely used in tea plantations. The objective of the present study was to evaluate the dissipation of carbofuran and carbaryl during the growth periods of Oolong tea, processing and roasting. Analysis of the residual insecticides was carried out using high-pressure liquid chromatography with a post-column fluorescence detector. Results showed that in the tea field carbofuran dissipated faster then carbaryl. Manufacturing processes of Oolong tea further reduced the carbofuran and carbaryl contents. The persistence of carbofuran and carbaryl was decreased with increasing roasting temperature. From the results, we conclude that the presence of carbofuran and carbaryl in tea can be reduced by proper field management, manufacturing and roasting processes.

Biofertilizers can help improve soil quality, promote crop growth, and sustain soil health. The photosynthetic bacterium Rhodopseudomonas palustris strain PS3 (hereafter, PS3), which was isolated from Taiwanese paddy soil, can not only exert beneficial effects on plant growth but also enhance the efficiency of nutrient uptake from applied fertilizer. To produce this elite microbial isolate for practical use, product development and formulation are needed to permit the maintenance of the high quality of the inoculant during storage. The aim of this study was to select a suitable formulation that improves the survival and maintains the beneficial effects of the PS3 inoculant. Six additives (alginate, polyethylene glycol [PEG], polyvinylpyrrolidone-40 [PVP], glycerol, glucose, and horticultural oil) were used in liquid-based formulations, and their capacities for maintaining PS3 cell viability during storage in low, medium, and high temperature ranges were evaluated. Horticultural oil (0.5 %) was chosen as a potential additive because it could maintain a relatively high population and conferred greater microbial vitality under various storage conditions. Furthermore, the growth-promoting effects exerted on Chinese cabbage by the formulated inoculants were significantly greater than those of the unformulated treatments. The fresh and dry weights of the shoots were significantly increased, by 10–27 and 22–40 %, respectively. Horticultural oil is considered a safe, low-cost, and easy-to-process material, and this formulation would facilitate the practical use of strain PS3 in agriculture.

Proteins are essential to rice caryopsis development and quality formation. High temperature is an important environmental factor, which may decrease grain quality. In the present study rice caryopsis proteins were profiled by two-dimensional polyacrylamide gel electrophoresis, and differentially expressed proteins were analyzed by liquid chromatography/tandem mass spectrometry. Expressions of more than 400 polypeptide spots during caryopsis development, in response to temperature treatments or between varieties were monitored. Among them, more than 70 differentially expressed polypeptides were analyzed by liquid chromatography/tandem mass spectrometry. We identified 54 proteins with known functions. Of these, 21 were involved with carbohydrate metabolism, 14 with protein synthesis and sorting, and 9 with stress responses. Waxy (Wx) proteins and glutelins were the most significant spots, which increased significantly during development. Allergen-like proteins, PPDK and NADH-SDH, also were expressed during development, implying their physiological roles in caryopsis. Expression of large isoforms of Wx proteins was correlated with the amylose content of rice caryopses. One protein with high GC content in its DNA sequence was correlated with the chalky trait of kernels. High temperature (35/30 degrees C) decreased the expression of Wx proteins, allergen-like proteins, and elongation factor 1beta, but increased the expression of small heat shock proteins (sHSP), glyceraldehyde-3-phosphate dehydrogenase, and prolamin. sHSP was positively correlated with the appearance of chalky kernels. During development, glutelins were phosphorylated and glycosylated, indicating that these molecules were post-translationally modified. Possible functions of the expression of candidate proteins on the grain quality are discussed.

Kernel abortion in maize (Zea mays L.) can cause significant reductions in yield. Abortion usually commences early in development and frequently occurs because of stresses such as water deficit or low light. Polyamines have been implicated in development processes of fruits and seeds, but in maize the changes of polyamine levels during kernel growth are still unclear. The objectives of this study were to investigate the roles of polyamines in the early stages of kernel growth and kernel abortion. Two single-cross hybrids with different kernel abortion characteristics were grown in a greenhouse with shade treatment. During early development of normal, naturally aborting, and shade-induced aborting kernels, temporal changes in the concentrations of endogenous putrescine (PUT), spermidine (SPD) and spermine (SPM) and their free, perchloric acid (PCA)-soluble conjugated, and PCA-insoluble bound forms, were measured. Changes in DNA content and the number of endosperm nuclei were also measured. Total polyamine levels in normal kernels rapidly increased 4 to 6 d after pollination (DAP), and peaked during active endosperm cell division. The most abundant polyamines were, in order, PCA-soluble conjugated PUT, PCA-soluble conjugated SPD, and free PUT. Aborting kernels had significantly lower levels of polyamines than normal kernels after 4 DAP. The low polyamine levels were temporally associated with a low number of endosperm nuclei and low DNA content. The results suggest that polyamines may be involved in the regulation of early endosperm development in maize.

To determine the combinative effects of tanshinone IIA (Tan IIA) and trans-resveratrol (Resv) on cytotoxicity, apoptosis, cell-cycle arrest and DNA fragmentation in HepG2 human liver cancer cells.Cytotoxicity was detected by the cell proliferation and cytotoxicity WST-1 assay. Cell-cycle arrest and apoptosis were determined using flow cytometry analysis. DNA fragments were separated by gel electrophoresis.Tan IIA and Resv at mixture ratios of 1/2:1/2 and 1/3:2/3 exerted synergistic cytotoxicity comparable to that of cisplatin. Elevated proportions of sub-G1 and apoptotic cells were respectively found in the combinative treatments in comparison with hypothetic values of additive effects. Moreover, a more intensive pattern of apoptotic DNA fragmentation was visualized in combined treatments than in individual ones.Combining Tan IIA and Resv causes synergistic cisplatin-comparable, cytotoxicity and robustly induces apoptosis, sub-G1 cell cycle arrest and DNA fragmentation. This study provides evidence supporting further pre-clinical investigations of the combinational synergism.

Ozone is one of the major gaseous pollutants detrimental to crop growthand metabolism. The objective of this research was to study how ABA amelioratesthe effects of ozone on rice seedlings. Seedlings of two rice cultivars withdifferent sensitivities to ozone (Tainung 67, tolerant; and Taichung Native 1,sensitive) were treated with 400 ppb of ozone or ABA and 400ppb of ozone to determine their effect on growth, stomatalmovement, chlorophyll characteristics, and the activity of antioxidant enzymes.Activities of the enzymes SOD, APOD, GR and POD were significantly higher inthesensitive cultivar, TN 1, than in the tolerant cultivar, TNG 67. Seedlings ofthe sensitive cultivar pretreated with ABA (10 μM) weresignificantly more tolerant of ozone than control seedlings. Pretreatment withABA effectively reduced stomatal conductance and the degree of injury. Abscisicacid also increased ascorbate peroxidase and glutathione reductase activity.Ozone increased peroxidase activity in sensitive seedlings, but ABA decreasedperoxidase activity. The sensitive cultivar had a higher density of stomata onits leaves than the tolerant cultivar. The results suggest that ABA inducedtolerance to ozone may be more associated with its effects on stomatal movementthan on the modulation of antioxidant enzyme activity.

Soluble acidity has been used as one of major indexes to reflect the changes of rice (Oryza sativa L.) grain quality during storage. The acidity is in general visually examined by pH dye indicators or directly measured by a pH meter. By combining the characteristics of pH dye indicator, 96-well microplate, and microplate reader, we have developed a procedure capable of effectively measuring the pH value of rice grains at a single-grain level. First, from a pH-dye system prepared with methyl red and bromothymol blue, we scanned the spectral response to pH and determined that a wavelength of 630 nm showed the maximum response to pH changes with storage age of rice grains. By means of a 96-well microplate and plate reader, a pH standard curve was then constructed with a series of pH standard buffers and absorbance at 630 nm. The pH value of a single grain in a microplate well can be measured by incubating the grain with dye solution and reading absorbance. The proposed procedure offers an efficient means of measuring the change of soluble acidity in rice grains during storage on an individual-grain basis. The method may also rapidly detect the uniformity or blending status of fresh/old grains in a sample.

We have investigated the role of abscisic acid (ABA) in the regulation of polyamine biosynthesis in rice (Oryza sativa L.) seedlings exposed to chilling (5°C). In a chilling-tolerant cultivar (cv. Tainung 67, TNG.67), levels of free putrescine and activity of arginine decarboxylase (ADC, EC 4.1.1.19) in both shoots and roots, and levels of free spermidine/spermine and activity of S-adenosylmethionine decarboxylase (SAMDC, EC 4.1.1.50) in shoots increased after exposure to chilling. In a chilling-sensitive cultivar (cv. Taichung Native 1, TN.1), level of free putrescine and activity of ADC in shoots increased slightly after exposure to chilling while those in roots decreased. Activity of ornithine decarboxylase (ODC, EC 4.1.1.17) in both cultivars remained unchanged after exposure to chilling. α-Difluoromethylarginine (DFMA), an irreversible inhibitor of ADC, but not α-difluoromethylornithine (DFMO), an irreversible inhibitor of ODC, at 0.5 mM inhibited free putrescine accumulation in chilled TNG.67 and resulted in a decrease in chilling tolerance; a decrease in survival and an increase in electrolyte leakage. The effects of DFMA were partially reversed by the addition of 0.5 mM putrescine. In TNG.67, chilling induced an increase of free ABA levels first, then ADC activity and finally free putrescine levels. Fluridone, an inhibitor of ABA synthesis, at 0.5 mM inhibited the increase of free ABA levels, ADC activity and free putrescine levels in chilled TNG.67, and resulted in a less tolerance of TNG.67 to chilling; these effects could be reversed by the pre-chilling treatment of 10 μM ABA. Application of 10 μM ABA for 48 h before chilling not only rendered TN.1 tolerant to chilling but also induced a change of polyamine pattern to be similar to chilled TNG.67. It seems that, for the materials used in this study, one of strategies of rice seedlings to resist chilling stress is to raise ABA levels and, in turn, one of ABA's functions is to enhance the ADC-mediated putrescine synthesis.

Physiological and biochemical changes related to methyl jasmonate (MeJA)-induced chilling tolerance of rice (Oryza sativa L. cv. Taichung Native 1) seedlings were investigated. Treatment of whole plants with 10 mmol m -3 MeJA for 48 h before chilling (5 °C) was optimal for the induction of chilling tolerance. MeJA greatly improved the survival ratio of chilled seedlings and ameliorated chilling injury such as demolition of membrane structure (estimated by electrolyte leakage). MeJA also prevented water loss in chilled seedlings by reducing the opening of stomata and decreasing the root bleeding rate. Putrescine and spermine levels in shoots increased but spermidine levels decreased on exposure to MeJA. In roots, putrescine levels also increased and spermidine levels increased transiently on exposure to MeJA. Activities of arginine decarboxylase (ADC ; EC 4.1.1.19) and S-adenosylmethionine decarboxylase (SAMDC ; EC 4.1.1.50) in both shoots and roots increased on exposure to MeJA, while the activity of ornithine decarboxylase (ODC ; EC 4.1.1.17) remained unchanged. The MeJA-induced putrescine increase was inhibited by 50 mmol m -3 α-difluoromethylarginine (DFMA), an irreversible inhibitor of ADC, but not by 50 mmol m -3 α-difluoromethylornithine (DFMO), an irreversible inhibitor of ODC. The effect of MeJA on the induction of chilling tolerance was also reduced by 50 mmol m -3 DFMA. The effects of DFMA were partly prevented by 1 mol m -3 putrescine. This indicates that putrescine accumulation is required for the induction of chilling tolerance of rice seedlings by MeJA.

Changes of internal ABA levels in relation to anoxia- or ethylene-induced growth alterations were determined in etiolated rice ( Oryza sativa L. cv. Taichung Native 1) seedlings. An inverse relationship between ABA levels and growth was observed at the early growth stages of rice seedlings. When rice seedlings were exposed to anoxia or 10 μl/l ethylene, coleoptile elongation was enhanced while growth of roots and leaves was inhibited. In contrast, anoxia or ethylene induced a decrease of ABA levels in coleoptiles but an increase in roots and leaves, especially after 48 h of treatment. In addition, the anoxia- or ethylene-enhanced coleoptile elongation was inhibited by ABA ranging from 10 −7 M to 10 −4 M. Thus,results presented here indicate that ABA is an inhibitory modulator in the anoxia- or ethylene-induced morphological changes of etiolated rice seedlings.

Summary The role of abscisic acid (ABA), ethylene and polyamines in leaf senescence of tobacco exposed to flooding was investigated. Senescence of tobacco leaves was followed by measuring the decrease of protein. Flooding significantly promoted senescence of tobacco leaves and resulted in a higher ABA content than the controls throughout the entire 4-day experimental duration. Ethylene production in flooding-treated leaves was much higher than that in control leaves during the first day of the experiment. Putrescine and spermidine, but not spermine, were present in tobacco leaves throughout the experimental duration. Flooded leaves had higher levels of putrescine and spermidine than untreated leaves. It is concluded that ethylene, but neither ABA nor polyamines, is possibly involved in the regulation of flooding-promoted senescence of tobacco leaves.

The timing of developmental events and regulatory roles of auxin were examined in maize (Zea mays L.) endosperms. Zeatin, zeatin riboside, and indole-3-acetic acid (IAA) levels were determined by enzyme-linked immunosorbent (ELISA). Zeatin and zeatin riboside increased to maximal concentrations at an early stage (9 d after pollination [DAP]), corresponding to the stage when cell division rate was maximal. In contrast, IAA concentration was low at 9 DAP and abruptly increased from 9 to 11 DAP, thus creating a sharp decline in the cytokinin to auxin ratio. Coincident with the increase in IAA was an increase in DNA content per nucleus, attributed to postmitotic DNA replication via endoreduplication. Exogenous application of 2,4-dichlorophenoxyacetic acid (2,4-D) at 5 or 7 DAP hastened the time course of DNA accumulation per nucleus and increased the average nuclear diameter, whereas 2-(para-chlorophenoxy)isobutyric acid delayed such development. Exogenously applied 2,4-D hastened the accumulation of the zein polypeptides of apparent molecular masses of 12, 14, and 16 kD and the expression of mRNA hybridizing with a zein DNA probe. We conclude that an abrupt increase in auxin induces cellular differentiation events in endosperm, including endoredupliction and expression of particular zein storage proteins.

To provide insight into the regulatory roles of auxin and cytokinin in endosperm development, defective kernel ( dek ) mutants of maize ( Zea mays L.) were examined. The mutants dek 6, dek 18 and dek 26 had substantially lower indole-3-acetic acid (IAA) levels than wild-type counterparts while dek 8, dek 12 dek 24 had higher IAA levels than wild-type counterparts. The mutant dek 6 had a somewhat lower zeatin level than its wild-type counterpart. The mutation-induced changes in IAA levels and effects of exogenously-applied auxin were not consistently related to changes in numbers of nuclei per endorsperm; however, there was a correspondence between auxin level in endosperm and nuclear diameter, which is proportional to the extent of post-mitotic DNA synthesis (endoreduplication). We conclude that auxin may be involved in stimulating endoreduplication.

Changes of ABA levels in chilled rice (Oryza sativa L.) seedlings of two varieties were determined. On exposure to chilling, ABA concentration rapidly increased in the chilling-tolerant cultivar (cv. Tainung 67, TNG.67) but not in the chilling-sensitive cultivar (cv. Taichung Native 1, TN.1). Both detached shoots and roots of TNG.67 seedlings showed a significant ABA increase after exposure to chilling. TN.1 seedlings could not accumulate ABA under low temperature but well-watered status. Exogenous application of the ABA biosynthetic inhibitor, fluridone, reduced ABA accumulation, as well as survival ratio of chilled TNG.67 seedlings. Electrolyte leakage and leaf conductance were also increased by the inhibitor and the effects could be reversed by exogenously applied ABA. ABA concentrations in xylem sap of TNG.67 seedlings increased within 4 h after chilling, and this was temporally coincident with the reduction of leaf conductance. The roles of endogenous ABA in the tolerance of rice seedlings to chilling on a whole plant basis are discussed and suggested.

The present study was performed to understand the effects of high temperature (HT) during filling on the expression of storage proteins and the quality of rice grains. HT (35/30 °C day/night) reduced the weight, amylose content, and flour gel consistency of grains. It increased the accumulation of all classes of storage proteins at early filling stage but decreased the accumulation of prolamins at maturation. For albumins, the expressions of cyclophilin 2, peroxiredoxin, and HSP16.9 were differentially enhanced by HT. For globulins, HT decreased the accumulation of globulin but increased that of glyoxalase I and peroxiredoxin. HT enhanced the transcription of genes for glutelins, prolamins, globulins, and protein disulfide isomerase at early filling stage but decreased the expression of these genes at a later stage. Low amounts of prolamins and globulins, as well as low pH value, were found in sound, immature, and dead kernels grown under HT. The relationships among HT, storage proteins, and grain quality are discussed.

A multiresidue method was developed to determine 19 carbamate pesticides in tea samples. Optimizations of different parameters, such as the type of extraction solvents, clean-up cartridges, and elution solvents were carried out. The developed method used acetonitrile as extraction solvent, amino cartridge for adsorbents and acetone-n-hexane as the eluting solution. Nineteen carbamate residues were then analyzed by high-pressure liquid chromatography (HPLC) with fluorescence detector. The present results showed good linearity by correlation coefficients of more than 0.9999 for all analyses. Limits of detection and quantification varied from 0.0005-0.023 mg L(- 1), 0.008-0.077 mg L(- 1), respectively. Recoveries of sixteen carbamate pesticides ranged from 65% to 135% at the spiked level of 0.5, 1.0 and 2.0 mg L(- 1). The relative standard deviations were lower than 20% and coefficient of variations were lower than 15%. The results indicate that the proposed method provides an effective multi and trace level screening determination of carbamate pesticides residues for tea samples.