Search

Water, nutrient and light deficiency during the co-growth period are the major factors limiting the productivity of the apple–maize alley cropping system in Loess Plateau, China. Therefore, it is crucial to optimize the management of water and fertilizer in the region. The effects of different irrigation and fertilizer levels on photosynthetic characteristics, growth, yield, water consumption (ET) and water use efficiency were studied in a young apple-maize intercropping system during 2014–2016. The treatments included three levels of maximum irrigation, namely 50% (W1), 65% (W2), and 85% (W3) of field capacity (Fc), and three different NPK fertilization levels (289.0-118.0-118.0, 412.4-168.8-168.8 and 537.0-219.0-219.0 kg∙ha−1), which were designated F1, F2 and F3, respectively. In addition, the rain-fed (neither irrigation nor fertilizer) crop was included as the control (CK). The F1 significantly increased the net rate of photosynthesis (Pn) and leaf water-use efficiency (LWUE) of both apple and maize. For maize, the effect of irrigation was greater than that of fertilizers on water use, but smaller on growth indicators and yield. The ET of the alley cropping systems increased with the amount of irrigation but decreased as the dose of fertilizers increased. Growth and yield of maize increased when the amount of irrigation increased, but were inversely related to fertilizer dose. The canopy architecture appeared to be regulated through differential absorption of water and nutrients. The Pn and transpiration (Tr) in maize decreased as the distance from the tree line increased, and the extent of decrease grew over time, suggesting greater interspecific competition. It is recommended that dwarf crops should be planted after intercropping for 5 years according to the change in photosynthetic index with intercropping years under different treatments. Multiple regression analysis indicated the following regime to be optimal during the first 3–5 years of the intercropping in terms of the yield of maize and water use in the alley cropping system: maximum watering (85% Fc) and minimum fertilization (289.0-118.0-118.0 kg ha−1 NPK).

Amorpha fruticosa is often used to revegetate saline wasteland in the YinNan Irrigation Area, northwest China. However, the survival rate of transplanted A. fruticosa seedlings is constrained by its low tolerance to high soil salinity, drought, and low soil temperatures (Tsoil) at the early transplanting stage. This study aimed to evaluate the effects of three different mulches, including plastic mulch (PM), sand mulch (SM) and rice straw mulch (RSM), and control (CK) on the soil microenvironment and A. fruticosa seedling growth. The results indicated that PM (19.1–26.2 °C), followed by SM (18.6–26.1 °C), provided the highest Tsoil at 0–20 cm depth during the whole growing period, while RSM (16.5–21.5 °C) exhibited lower Tsoil than CK (15.8–22.0 °C) at all time except the later growing stage. RSM (7.1%–26.4%) retained soil water most effectively as compared to CK, followed by SM (3.2%–22.5%), and then PM (-0.6%–19.7%). PM (11.4%–18.5%) had the best performance in reduction of ECe at 0–80 cm depth, followed by RSM (10.5%–15.5%), and then SM (3.7%–7.4%). Still, PM exhibited the greatest improvement in soil structure. A. fruticosa seedlings grown in PM achieved the best stand establishment and growth characteristics, in which its root reached to 40–60 cm depth, while the counterparts in RSM showed the poorest performance in three mulching treatments. The results above suggest that PM is a promising strategy to promote the growth of transplanted halophytes in saline wasteland of the YinNan Irrigation Area and other areas with similar ecologies.

A field trial consisting of cotton grown employing a combination of ridge planting, mulching with film, and drip irrigation was laid out on a plot with severely saline soil in a typical inland arid area of Xinjiang. The effect of five levels of soil matric potential set up 0.2 m below the drip emitter, namely −5 kPa, −10 kPa, −15 kPa, −20 kPa, and −25 kPa, were studied in terms of changes in soil salinity (ECe), sodicity (SAR), crop growth and yield components. Drip irrigation increased the leaching of soil salts and decreased the ECe and SAR of each soil layer. Although the levels of soil salt rose again, in spring and winter, after irrigation was discontinued, the root zone (0–40 cm) remained less saline: the ECe and SAR value under the soil matric potential of −5 kPa and −10 kPa were 63% and 49% of its values in 2009 respectively, before the land was brought under cultivation (p ≤ 0.05), showing maximum leaching. The yield of cotton peaked at the soil matric potential of −5 kPa. The germination rate, which was the main factor that influenced the cotton yield, was 67% of that in non-saline soil in the first two years, and increased to 84% in the third year. After three years, the rate of germination in all the treatments exceeded 67%, and the highest rate (78%) was at −5 kPa; in the same treatment, boll yield was 4.40 g per plant. Except for germination rate and the yield of lint and seed, all the yield components increased significantly (p ≤0.05) as ECe and SAR decreased in 2010 and 2011. The correlation between soil salt (salinity and sodicity) and other components such as the number of cotton bolls per plant, the average weight of a boll, and lint percentage varied, probably because water supply was being regulated and, as a result, the physicochemical properties of the soil kept changing constantly. Taking into account the extent of leaching, crop growth, and yield, the lower limit for the soil matric potential should be −5 kPa at 20 cm below the dripper for the first three years during reclamation to promote cotton cultivation on the saline-sodic soil of Xinjiang.

Accurate assessments of soil organic carbon (SOC) and total nitrogen (TN) stocks and controlling factors are essential for understanding carbon and nitrogen sequestration in soil. In this study, we analyzed the spatial distribution and influencing factors of SOC and TN stocks to the depth of 3 m in a desert oasis ecotone of northwestern China. The study area has experienced large-scale transition of dunelands to irrigated croplands in the past 40–50 years. The results showed that the vertical distributions of SOC and TN stocks were well demonstrated by quadratic function forms. The SOC and TN stocks at 0–3 m depths in nabkha dunes were generally significantly higher than that in bare sand dunes. Additionally, after converting nabkha dunes to croplands, both SOC and TN stocks at the top 0.4 m depths increased with the extension of cultivation years, the mean SOC and TN stocks significantly increased from 0.396 to 0.992 kg·m−2 and from 0.053 to 0.096 kg·m−2, respectively. The strongest heterogeneity of SOC and TN generally appeared at top 0–0.4 m depths and decreased with the depth. The SOC and TN stocks in the nabkha dunes near the water areas were relatively higher, which may be suitable for croplands reclamation. It is noteworthy that land use brought a major influence of SOC and TN at top 0–0.4 m depths, whereas soil texture (clay and silt contents) was the main factor that controlled SOC and TN at deep soil depths (1–3 m). The results indicate that the nabkha dunes also increased carbon and nitrogen stocks throughout the entire 3 m soil profiles. While the demand for food is almost certain to increase in arid and semiarid China and other regions worldwide, the conversion from non-traditional croplands such as dunelands to croplands is likely going to continue.

The loess plateau of northern China has always been severely affected by drought and rainfall, impacting ecological integrity and sustainable development in particular. Super-absorbent polymers (SAPs) can relieve the pressure of water shortages and change the process of rainfall-runoff. In this study, SAPs were mixed with soil in percentages(weight ratio) of 0, 0.25%, 0.5%, 0.75%, 1% and 2%; then, these mixtures were applied in 5 cm depth layers in runoff plots of 5 m × 4 m for every treatment (T1, T2, T3, T4, T5). Artificial rainfall intensity was controlled at 40 mm/h, and the rainfall duration was 0.5 h when the soil physical and chemical properties were surveyed. With SAPs, the initial runoff time of different treatments increased by 21.5-102.7%; the amount of surface runoff decreased remarkably; the SAPs could reduce the loss of soil and water: the runoff reduction effect was 24.6% (T1), 41.5% (T2), 46.5% (T3), 50.7% (T4), and 60.6% (T5); the sediment reduction effect was very significant at 58.8% (T1), 74.1% (T2), 85.6% (T3), 80.9% (T4), and 75% (T5); and the lowest losses of total nitrogen (TN 0.09 kg), total phosphorus (TP 5.02 g) and total potassium (TK 0.08 kg) were measured in T3,with 14.9%, 14.2% and 13.1% that of the control (CK), respectively. The soil moisture content increased by 19.2%, 32.5%, 33.5% and 31.3% compared to CK in the different soil layers; SAPs could raise the soil temperature by 0.72 °C (T5) and lower the soil temperature by 0.53 °C (T5) in September and July, respectively. The aboveground biomass and underground biomass of the treatments increased by a maximum value of 84.4% in T3, which was 38% greater than CK, and the vegetation in T3 (44 kinds) was the most abundant and it was 69.2% more than CK (26 kinds). The effect was not always positively correlated with the percentage of SAPs. The application of SAPs in this study showed a comprehensive utility (soil erosion prevention, redistribution of soil water and temperature, maintenance of fertility and the synergy between SAPs and plants), which suggest that the most basic goal, to ensure socio-economic and ecological sustainability in dryland systems, is obtained.

Tamarisk (Tamarix ramosissima) plants are widely distributed in semi-arid regions with saline soils. In these environments, the survival and sustainability of the Tamarisk plants are critically related to the availability and distribution of soil water and salt. In this study, we analyzed the soil water content (SWC) and soil electrical conductivity (EC) to the depth of 60 cm in natural Tamarisk communities, located in a semi-arid saline region of northwestern China, in July 2016 (a normal period) and July 2017 (a dry period). The results showed that SWC varied from 1.91 to 7.82% and soil EC ranged from 9.65 to 25.38 mS/cm in the 0–60 cm soil layer. Despite the deficiency of precipitation in the study period of 2017, the SWC in all plots was higher at the 20–60 cm depth than that of the normal study period in 2016. Compared to 2016, the soil was also less saline in 2017, representatively by lower soil EC values at the 0–40 cm depth. Additionally, the SWC decreased with Tamarisk density, indicating that Tamarisk plants increase water consumption. The SWC and soil EC both revealed “island” distribution, with highest level found inside or underneath the Tamarisk plant canopies. Both the SWC and soil EC presented a strong or moderate spatial dependency, and the spatial dependency in soil EC were significantly affected by community composition. Correlations (Pearson’s r) showed that there were positive correlations between SWC and soil EC. The results above indicate that Tamarisk communities can ameliorate the semi-arid high saline soil environment, and that the growth and distribution of Tamarisk plants influence the spatiotemporal variability of SWC and soil EC. In addition, the results also demonstrate that the possible appropriate density in the process of constructing Tamarisk plants should be considered in order to achieve the optimal water condition. The study may provide a scientific basis for the ecological restoration and halophytes establishment in the semi-arid saline region of northwestern China and other areas with similar ecologies.

Background The main issue of this study is to demonstrate whether M-phase phosphoprotein 8 (MPP8) affect gastric tumour growth and metastasis. Methods Retrospective study was proceeded in 280 patients’ surgical specimens with different disease stages. Lentivirus delivery of short hairpin RNA targeting MPP8 was also used to explore the function of MPP8 in gastric cancer cells. Quantitative real-time PCR and western blot were applied to measure apoptosis and metastasis relative biomarker. Results The present study revealed that MPP8 expression was higher in surgical specimens from patients with gastric cancer (vs. normal adjacent tissues), and that elevated expression was associated with male sex (vs. female sex), intermediate differentiation (vs. poorly differentiated cancer), and later stage (vs. earlier stage). Furthermore, MPP8 overexpression in tumour tissues was marginally associated with a poor prognosis, with a significant relationship between MPP8 overexpression and prognosis among patients with poorly differentiated gastric cancer. Inhibition of MPP8 in these cells significantly suppressed proliferation and colony formation, promoted apoptosis, and repressed invasion. Furthermore, silencing of MPP8 remarkably increased the expression of apoptosis-related proteins (p53, Bax, and PARP), and down-regulated Bcl-2 expression. Silencing of MPP8 also decreased the expression of metastasis pathway-related proteins (N-cadherin and vimentin), and as well as the levels of anti-oncogene ZEB1, MET, and KRAS mRNA. Conclusions These results suggest that MPP8 plays a critical role in regulating gastric cancer apoptosis and metastasis via the p53/Bcl-2 and EMT-related signalling pathways, respectively, which may indicate that MPP8 is a promising target for treating gastric cancer. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

To get an insight into when dewfall will occur and how much to expect we carried out extensive calculations with the energy balance equation for a crop surface to 1) identify the meteorological factors which determine dewfall, 2) establish the relationship between dewfall and each of them, and 3) analyse how these relationships are influenced by changes in these factors. The meteorological factors which determine dewfall were found to be air temperature (T(a)), cloud cover (N), wind speed (u), soil heat flux (G), and relative humidity (h(r)). Net radiation is also a relevant factor. We did not consider it explicitly, but indirectly through the effect of temperature on the night-time radiation balance. The temperature of the surface (T(s)) where dew forms on is also important. However, it is not a meteorological factor, but determined by the aforementioned parameters. All other conditions being equal our study revealed that dewfall increases linearly with decreasing N or G, and with increasing h(r). The effect of T(a) and u on dewfall is non-linear: dewfall initially increases with increasing T(a) or u, and then decreases. All five meteorological factors can lead to variations in dewfall between 0 and 25 W m(-2) over the range of their values we studied. The magnitude of the variation due to one factor depends on the value of the others. Dewfall is highest at N=0, G=0, and h(r)=1. Ta at which dewfall is highest depends on u and vice versa. The change in dewfall for a unit change in N, G or h(r) is not affected by the value of N, G or h(r), but increases as T(a) or u increase. The change in dewfall for a unit change in Ta or u depends on the value of the other four meteorological factors.

A total of 209 unrelated patients of predominantly Han Chinese ethnicity and with X-linked Alport's syndrome, a clinically heterogeneous hereditary nephritis, were enrolled in the present study to evaluate the ability to make a clinical diagnosis and perform molecular genetics analysis using skin biopsy. A negative or mosaic α5(IV) chain staining in the epidermal basement membrane was detected in 86.2% of male and 93.5% of female patients. COL4A5 mutations were identified in 85% of male patients with a negative α5(IV) chain staining pattern in the epidermal basement membrane. With use of skin biopsy and immunostaining, 16.4% of our patients were diagnosed before 3 years of age, and the youngest was diagnosed at 1 year of age. COL4A5 mutations were detected in 22 patients with normal epidermal basement membrane staining for the α5(IV) chain. Analysis of COL4A5 cDNA fragments from skin fibroblasts yielded a mutation detection rate of 83%, which was particularly valuable for identification of cryptic splicing mutations. Furthermore, 83% of COL4A5 mutations identified in the present study were novel. Thus, skin biopsy is a practical approach for the clinical diagnosis and molecular genetic analysis of X-linked Alport's syndrome.

Summary The amount and temporal distribution of dewfall on grass, maize and winter barley was measured with four high precision weighing lysimeters at a site in northern Germany during 2004–2005 to quantify the contribution of dewfall to the water balance of the region and to assess how dewfall is affected by the vegetation cover. Two lysimeters were under continuous grass, two were cropped (maize from April through September 2004, followed by winter barley until July 2005, fallow the rest of the time). Observed dewfall ranged from 27.1 to 31.8 mm per year, which was 5.5–6.9% of the annual rainfall. In several months of the study period dewfall was >20% of the monthly precipitation. On fallow lysimeters there were fewer nights with dewfall and less dewfall per event than on lysimeters with grass. After crops were planted the number of dewfall-nights and the amount of dewfall per event rose quickly and eventually surpassed that on the lysimeters with grass. After harvest both parameters dropped well below the values on the grass lysimeters again.