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The carbon cycle of saline–alkali ecosystems will be affected to some extent in the context of future global warming. Therefore, we investigated the net ecosystem exchange (NEE) of three typical crops (wheat, maize and soybean) in the saline–alkaline land of the Yellow River Delta. To further investigate CO2 fluxes, NEE was decomposed into gross primary productivity (GPP) and ecosystem respiration (Re). In terms of seasonal variation, wheat and soybean were carbon sources in the early and late growth periods, and carbon sinks in the rest of the period, whereas maize was a carbon sink in the majority of the period, and maize had good carbon sink potential. The cumulative NEE during the growth periods for wheat, maize, and soybean were 414.86, 258.24 and 228.92 g cm−2, respectively, and the daily variation showed that the peak NEE values for the three crops preceded the peak values of both GPP and ecosystem respiration, occurring approximately at 12:00 a.m. In the correlation analysis, NEE and GPP of the three crops were well correlated with photosynthetic photon flux density and net radiation, whereas Re was significantly correlated with air temperature. Through a comparative analysis of CO2 fluxes within various agricultural ecosystems, our findings indicated that wheat demonstrated moderate carbon sequestration capabilities, whereas maize and soybean exhibited strong carbon sink characteristics. Notably, saline–alkali crops exhibited lower Re, whereas GPP levels remained at a moderate range. Therefore, under the global warming trend, the respiration of saline crops and soils will be affected and may change the original carbon sink into a carbon source. Hence, implementing suitable measures targeting saline–alkali areas, such as the establishment of an effective crop rotation system and the enhance saline–alkali land conditions, can reduce emissions of greenhouse gases, thus reducing the pressure of global warming and maintaining a stable carbon cycle in saline–alkali land. [ABSTRACT FROM AUTHOR]

Rice has a high water requirement, but water use efficiency (WUE) in rice has always been low, and the status of rice WUE and the factors influencing it in various countries around the world is currently unclear. Therefore, this paper collected 56 articles from 2000 to 2022, through which WUE data from different countries and different provinces in China were collated, and the effects of various water‐saving irrigation technologies on WUE of rice and irrigation water use were analysed using the method of Meta‐analysis. The results of this paper show that rice WUE is low in most countries, with the lowest WUE of 0.28 kg/m3 in Thailand and the highest WUE of 1.25 kg/m3 in Bangladesh among the countries included in this study, and flood irrigation is used in most countries. Compared to flood irrigation, all water‐saving irrigation involved can increase rice WUE and reduce irrigation water input, alternate wet and dry irrigation (W1), and controlled irrigation (W2) were able to increase the WUE of rice by 49.86%, 84.74%, and reduce the irrigation water input by 36.55%, 39.55% respectively. Among the six types of water‐saving irrigation input, dry cultivation (W3) had the most significant effect on increasing WUE and reducing irrigation water, reaching 2.02 times and 67.53%, respectively. Based on the annual rainfall (R) and the application of water‐saving irrigation in Asia, sub‐regionally applicable water‐saving irrigation technologies are recommended. W3 is recommended when R <200 mm, W2 is recommended when 200 mm < R < 800 mm, and W1/W2/shallow alternate wet and dry irrigation (W5) is recommended when R >800 mm. According to the data collected in this paper, W1, W2, W3, and W5 can save 3.40 × 1011 m3, 3.78 × 1011 m3, 2.52 × 108 m3, 2.22 × 1011 m3 of irrigation water, respectively. Based on the calculations in this paper, different water‐saving irrigation techniques can save 3.50 × 1011 m3 of water in Asia according to the recommendations. To promote water‐saving irrigation technology, countries need to formulate policies to ensure the development of water‐saving irrigation technology, raise farmers' awareness of water conservation, and provide training and financial support. Promoting the use of different water‐saving irrigation technologies for different regions can significantly reduce irrigation water and increase the WUE of rice, which is important in addressing the challenges of global water scarcity. [ABSTRACT FROM AUTHOR]

Generalized synchronization in a drive-response Chua circuits is investigated. A cascade of transitions to GS is observed with increasing the interaction strength. The mechanism on the transitions to GS is given based on the asymptotic behaviors of response dynamics. [ABSTRACT FROM AUTHOR]

Develops an approach for evaluation of sustainable development in Guangzhou, China between 1986 and 1995. Calculation of the sustainability development level index at different levels of tiers; Developmental stages; Coordination degree among the economic, social, and natural subsystems.

The enzyme C-14 sterol reductase is involved in biosynthesis of brassinosteroids (BR) and sterols, as well as plant development. OsFK1, a member of the sterol biosynthesis pathway located in the endoplasmic reticulum (ER), encodes C-14 sterol reductase. However, there is little research on the function of C-14 sterol reductase in rice. Compared with the wild type, an osfk1 mutant showed dwarf phenotype and premature aging in the second leaf during the trefoil stage, and abnormal development of leaf veins during the tillering stage. The osfk1 mutant showed signs of aberrant PCD, as evidenced by TUNEL staining. This suggested that high ROS buildup caused DNA damage and ROS-mediated cell death in the mutant. The osfk1 mutant also showed decreased chlorophyll content and aberrant chloroplast structure. Sequencing of the osfk1 mutant allele revealed a non-synonymous G to A mutation in the final intron, leading to early termination. Here, we identified the OsFK1 allele, cloned it by Mutmap sequencing, and verified it by complementation. HPLC-MS/MS assays demonstrated that the osfk1 mutation caused lower phytosterol levels. These findings showed that the OsFK1 allele encoding C-14 sterol reductase is involved in phytosterol biosynthesis and mediates normal development of rice plants. [ABSTRACT FROM AUTHOR]

An important element of the hydrologic cycle, the hydrometeorological parameter of evapotranspiration (ET), is critical in the development of effective water resources planning and irrigation scheduling. The ET varies in response to changes in resistance at the canopy surface rc and soil moisture content u, especially under water-saving irrigation (WSI) practices. Drawing on data collected by eddy covariance in WSI rice paddies in eastern China in 2015 and 2016, variations in ET were studied by calculating and analyzing hourly canopy resistance rch and daily canopy resistance rcd. Discrepancies were noted between true daily ET (ETtrd) with respect to the estimated daily ET (ETd rc) at different periods [0700-1600 local time (UTC 1 8)]. To estimate ETd rc in the WSI rice fields, the mean rch value between 0900 and 1000 LT, and between 1000 and 1100 LT performed considerably better than rch for a single time. Seasonal estimated ET (ETrcs) can be accurately calculated by interpolating rcd at different time intervals, thereby achieving a greater correlation and consistency at 2-day intervals. Then a generalized two-segment line of rcd variation was used to calculate ETs rc, achieving good results and showing that in the absence of observational data, ETs rc could be easily calculated through a simplified pattern of variability. In conclusion, an ET temporal upscaling method for a WSI paddy, based on variation in rch and rcd values, was optimized and is recommended for local application. Future work will focus on temporal upscaling of ET by extrapolating remote sensing instantaneous estimates to daily values. [ABSTRACT FROM AUTHOR]

• Controlled drainage (CD) reduced nitrogen (N) losses after fertilization from controlled irrigation (CI) paddy fields. • Subsurface outflow after fertilization from CI paddy fields was decreased under CD. • CD increased total N concentrations in 0–10 cm soil solution and subsurface outflow of CI. • The combination of CI and CD is a useful tool to reduce N loss from paddy field. The effect of controlled drainage (CD) on nitrogen (N) losses from controlled irrigation (CI) paddy fields through subsurface drainage and ammonia volatilization (AV) was investigated by managing water table control levels (WTC) with a lysimeter equipped with an automatic water table control system. Three drainage treatments were implemented, namely, controlled water table depths 1–3. The increases of the WTC resulted in a high proportion of groundwater levels below the WTC, which reduced the subsurface outflow from CI paddy fields by 30.5% during the first week after fertilization. Total N concentrations in the 0–10 cm soil solution and subsurface drain water were higher as the WTC increased. The increase of the WTC during the first week after fertilization could effectively decrease the N losses from CI paddy fields by 9.5%, and the first weekly N losses through subsurface drainage and AV after fertilization were reduced by 17.2% and 9.3%, respectively. The large reductions in subsurface outflow decreased the first weekly N losses through subsurface drainage after fertilization. The retention time of shallow water in CI paddy fields was extended with the increases in WTC, which may reduce the first weekly AV losses after fertilization. Results show that the combination of CI and CD may be an effective water management method for mitigating N losses through subsurface drainage and AV after fertilization from paddy fields. [ABSTRACT FROM AUTHOR]

reveal the impact of vertical non-uniform distribution of soil moisture on nitrous oxide (N2O) emissions, incubated experiments were conducted from April to August 2013 on silty clay and sandy loam with four watering regimes [surface watering (SW) and subsurface watering application to levels 12, 15, and 18 cm below soil surface (SUW12, SUW15, SUW18)]. Short-term pulse emissions of N2O from both soils during the drying process were observed. The soil water-filled pore space (WFPS) at 0-12 cm depths for peak N2O fluxes in SW and SUW soils fell within 34-66%, 22-72%, 25-35%, and 19-39% for silty clay and sandy loam, respectively. Our results also suggest that the N2O fluxes from soil of sily clay with higher N content are much higher than that from sandy loam, and N2O were more easily influenced by soil moisture in SW soils than in SUW soils. However, more research is needed to identify an ideal soil-wetting pattern and the way to realize the ideal soil-wetting pattern, especially on soil with plant growth and fertilization. [ABSTRACT FROM AUTHOR]

The diurnal pattern of nitrous oxide (N2O) emissions is essential in understanding how weather and soil conditions influence the daily mean estimate of N2O fluxes. Incubation experiments were conducted to investigate the effects of vertical soil moisture distribution patterns on diurnal variation of N2O emissions. Clear diurnal patterns of N2O emissions on both surface watering (SW) and subsurface watering (SUW) treatments (SUW12, SUW15, and SUW18) were detected from soil sample (I), silty clay, and soil sample (II), sandy loam, where peak N2O fluxes usually occurred between 12:00 and 18:00 h. Different vertical watering patterns resulted in changes in the daily range of N2O fluxes and peak time. Mean fluxes from the SUW12, SUW15, and SUW18 treatments were 37.4%, 32.7%, and 43.3% lower than those from SW treatments from soil sample I, and 32.0%, 40.3%, and 41.1% from soil sample II. Moisture distribution patterns under SUW soils could be effective to mitigate N2O emissions. The N2O emissions from soil sample I ranged from178.3 to 2741.0 μg N2O m-2 h-1, which was more than in soil sample II with 7.0 to 83.7 μg N2O m-2 h-1. The different soil texture and N content level might account for the differences in magnitude of N2O fluxes from soils. The optimal soil moisture condition for peak N2O fluxes in the SW treatment had relatively narrower ranges than the SUW treatments with 46% to 60% water-filled pore space (WFPS) for soil sample I and 26% to 34% WFPS for soil sample II even though surface soil moisture for peak N2O fluxes were somewhat different from the previously reported optimal soil moisture range of 45% to 75% WFPS. [ABSTRACT FROM AUTHOR]

This study aimed to investigate chlorophyll content and photosynthetic characteristics of 17 pepper inbred lines which were selected independently. The results showed that chlorophyll contents significantly varied among different inbred lines. To be specific, chlorophyll content of No. 68 inbred line was significantly higher than that of other 14 inbred lines; chlorophyll content of No. 55 inbred line was significantly lower than that of other 15 inbred lines. The chlorophyll content of various inbred lines showed a decreasing order of No. 68 > No. 47 > No. 66 > No. 62 > No. 63 > No. 60 > No. 61 > No. 64 > No. 56 > No. 67 > No. 65 > No. 48 > No. 59 > No. 58 > No. 57 > No. 69 > No. 55 ; the photosynthetic rate of various inbred lines showed a decreasing order of No. 68 > No. 57 > No. 60 > No. 48 > No. 58 > No. 47 > No. 62 > No. 63 > No. 64 > No. 65 ; the maximum photosynthetic rate of No. 65 inbred line was significantly lower than other seven inbred lines, while no significant difference was observed among other nine inbred lines. [ABSTRACT FROM AUTHOR]

thermal imager was used for measuring the canopy temperature to calculate crop water stress index (CWSI) of rice under water deficit condition. The CWSI varied diurnally with peaks appeared at noon, and soil water deficit led to higher CWSI values during noon. Transpiration rate (Tr), stomatal conductance (gs) and net photosynthetic rate (Pn) were high at low CWSI, and reduced with increasing CWSI. The relationship between CWSI and Pn, Tr or gs at noon was described by quadratic polynomial equations. At critical noon, CWSI values for the decline trend in Pn (0.303, 0.385 and 0.446 at tillering, panicle initiation to booting, milk to soft dough stage) were higher than for decline in Tr and gs. Assuming a 5% reduction in Pn from maximum is moderate water deficit, the critical CWSI values were 0.420, 0.472 and 0.536 at tillering, panicle initiation to booting and milk to soft dough stages. CWSI at 14:00 decreased significantly with increasing relative soil moisture contents. There was a slight difference between the linear relations under different vapor pressure deficit (VPD) conditions. The critical relative soil moisture contents for a 5% reduction in Pn were 1.57%, 1.18% and 1.27% higher under high VPD than low VPD conditions. It implied that rice water status was determined in conjunction with field soil moisture content and air aridity. The water deficit diagnosis based on canopy temperature tracked by thermal infrared imager is a promising method in reflecting the conjuncted function of soil moisture deficit and air aridity on crop water status. [ABSTRACT FROM AUTHOR]

To reveal the impact of irrigation management on the release and leaching of soil metals (Cu, Zn, Pb, Cr, and Cd), deep percolation rate and metals contents in soil solutions were observed in rice fields with non-flooding controlled irrigation (NFI) and flooding irrigation (FI) treatments. The contents of Cu and Cr in the deep solutions were safe according to the environmental quality standard for groundwater, but contents of other metals might lead to groundwater contamination, especially for Cd. The release of metals in surface soil was increased for NFI because the wetting-drying cycles in NFI fields resulted in less reluctant and high decomposition and mineralization of soil organic matter in surface soil, and consequently enhanced the release of soil metals into solutions. Seasonal metals leaching losses in NFI fields were 44.9-53.8% lower than in FI, due to the large reduction in both deep seepage rates and metals concentrations in deep soil solutions. Higher release of metals in NFI surface soils might lead to higher bioavailability of micronutrients (Cu and Zn) to crops, but higher risks in toxic metals (Pb, Cr, and Cd) uptakes. [ABSTRACT FROM AUTHOR]

The transfer of membrane proteins between cells during contact, known as trogocytosis, can create novel cells with a unique phenotype and altered function. We demonstrate that trogocytosis is more common in multiple myeloma (MM) than chronic lymphocytic leukemia and Waldenstrom macroglobulinaemia; that T cells are more probable to be recipients than B or natural killer cells; that trogocytosis occurs Independently of either the T-cell receptor or HLA compatibility; and that after trogocytosis, T cells with acquired antigens can become novel regulators of T-cell proliferation. We screened 168 patients with MM and found that CD86 and human leukocyte antigen G (HLA-G) were antigens commonly acquired by T cells from malignant plasma cells. CD3+CD86acq+ and CD3+ HLA-Gacq+ cells were more prevalent in bone marrow than peripheral blood samples. The presence of either CD86 or HLA-G on malignant plasma cells was associated with a poor prognosis. CD38++ side population cells expressed HLA-G, suggesting that these putative myeloma stem cells could generate Immune tolerance. HLA-G+ T cells had a regulatory potency similar to natural Tregs, thus providing another novel mechanism for MM to avoid effective immune surveillance. [ABSTRACT FROM AUTHOR]