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Coordinated uptake and utilization of water and nitrogen (N) is important for high-yield and high-efficiency cultivation of winter wheat. The relationship between soil water consumption and N uptake and utilization has not previously been widely investigated. The purpose of this study was to examine the regulatory effects of different seeding rates with wide-space sowing on water consumption and N accumulation and translocation of winter wheat. A field experiment was conducted in the southeastern part of the Loess Plateau between 2016 and 2018, in which winter wheat was sown using the wide-space method (row spacing: 22–25 cm, and seedling bandwidth: 5–8 cm) and five seeding rates: 150, 225, 300, 375, and 450 kg seeds ha−1. The results showed that soil water consumption increased significantly with an increase in the seeding rate from 150–300 kg seeds ha−1, especially from the jointing to maturity stage of wheat growth. At 300 kg seeds ha−1, N translocation from the leaf and stem + sheath to the grains was significantly enhanced, which increased grain N accumulation. The maximum tiller number, water use efficiency, N uptake efficiency, and partial factor productivity from applied N were all recorded at a seeding rate of 300 kg seeds ha−1, thus, grain yield increased significantly by 6–18%. Correlation analysis showed that N accumulation from the sowing to anthesis stage, pre-anthesis N translocation, and the grain yield of winter wheat were closely related to total soil water consumption. Overall, the findings of this study have demonstrated that wide-space sowing of winter wheat at a 300 kg seeds ha−1 seeding rate improved the water use efficiency and N uptake efficiency, which in turn increased the tiller number and grain yield.

Deep ploughing and subsoiling are important management practices used for mitigating the risk of soil compaction under long term no-tillage or reduced tillage practices. These fallow tillage methods have been widely applied in the Loess Plateau region of China to improve soil water availability and preventing soil erosion. To investigate the effect of different tillage practices for increasing the production of winter wheat (Triticum aestivum L.) and their relationship with precipitation distribution in the semiarid southeast region of the Loess Plateau, a six-year field study was conducted from 2009 to 2015, using three tillage treatments: deep ploughing (DP), subsoiling (SS), and no-tillage (NT). Our results indicated that DP and SS treatments increased soil water storage in the 0–300 cm soil layer at sowing and soil organic carbon in the 0–20 cm soil layer at maturity. In addition, DP and SS increased soil water consumption in the 0–180 cm soil layer from sowing to anthesis, and in the 120–300 cm layer from anthesis to maturity of wheat. Furthermore, the DP and SS treatments significantly increased the root length, root surface area, and the number of root tips in the 0–80 cm and aboveground dry biomass at maturity. Additionally, DP and SS treatments increased the grain yield by 31% and 26%, precipitation use efficiency by 32% and 26%, and water use efficiency by 12% and 11% respectively, as compared with those of the NT treatments. Pearson’s correlation analysis showed that soil water consumption was significantly positively correlated with precipitation from sowing to jointing and anthesis to maturity. In addition, grain yield had a significant positive correlation with precipitation during the fallow season, particularly in the SS treatment. Moreover, grain yield was significantly positively correlated with soil water consumption in the 0–180 cm soil layer from sowing to jointing, and at 60–240 cm soil depth from jointing to maturity. In conclusion, under low precipitation, DP was more favorable for winter wheat than SS, whereas, under high precipitation, SS was more beneficial than DP.

Water availability is a major constraint for wheat production in the southeast of the Loess Plateau, China. Plastic mulch exhibits greater potential in rainwater harvesting while nitrogen (N) fertilizer has a strong effect on soil water utilization. Most of annual precipitation in the Loess Plateau occurs in summer. Rainwater retention in summer fallow becomes very important for winter wheat production in the dryland of the Loess Plateau. Straw mulching in summer fallow are commonly used to prevent water evaporation from soil surface and retain rainwater. Recently plastic mulching has also been used. Nitrogen inputs have also a significant impact on soil water utilization and yield production. However, there is little information available for the effects of full coverage of plots with plastic mulch (PM) in summer fallow on soil water storage at sowing and N rates interact with the soil water utilization in winter wheat yield, water use efficiency (WUE) and grain protein concentration (GPC). Therefore, field experiments were conducted in three consecutive years with variable rainfall. The results showed that PM in summer fallow increased soil water storage at sowing by at least 50 mm, and water storage efficiency was the highest (56.5%) in the dry season. Spatio-temporal dynamics in the soil water storage of 0–300 cm depth exhibited a downward movement with crop development. Approximately half of soil water consumption from flowering to maturity was derived from the 200–300 cm soil layers. The optimal N rate with PM increased grain yield by 27% in the wet season, 36% in the normal season, and 41% in the dry season. PM in combination with optimized N could improve WUE only when annual rainfall is equal to or above the yearly average. Furthermore, evapotranspiration is negatively correlated with GPC although the soil water consumption from 200 to 300 cm depth is positively correlated with post-anthesis N uptake. This suggests that the additional N is needed to further increase GPC. In the season with soil water storage of 550–600 mm at sowing, the N rate of 225 kg ha−1 with PM could achieve the highest yield and 13.2% of GPC. In the season with soil water storage of 450–550 mm at sowing, the N rate of 150 kg ha−1with PM could achieve the highest yield, and 14.3% of GPC. When the season with soil water storage of approximately 400 mm, the N rate of 75 kg ha−1 with PM achieved the highest yield, and 15.0% of GPC. Our results indicate that adjusting N fertilizer inputs based on seasonal variation in summer rainfall could enhance wheat yield and GPC in the southeast region of the Loess Plateau.

Sowing date and seeding rate are critical for productivity of winter wheat (Triticum aestivum L.). A three-year field experiment was conducted with three sowing dates (20 September (SD1), 1 October (SD2), and 10 October (SD3)) and three seeding rates (SR67.5, SR90, and SR112.5) to determine suitable sowing date and seeding rate for high wheat yield. A large seasonal variation in accumulated temperature from sowing to winter dormancy was observed among three growing seasons. Suitable sowing dates for strong seedlings before winter varied with the seasons, that was SD2 in 2012–2013, SD3 in 2013–2014, and SD2 as well as SD1 in 2014–2015. Seasonal variation in precipitation during summer fallow also had substantial effects on soil water storage, and consequently influenced grain yield through soil water consumption from winter dormancy to maturity stages. Lower consumption of soil water from winter dormancy to booting stages could make more water available for productive growth from anthesis to maturity stages, leading to higher grain yield. SD2 combined with SR90 had the lowest soil water consumption from winter dormancy to booting stages in 2012–2013 and 2014–2015; while in 2013–2014, it was close to that with SR67.5 or SR112.5. For productive growth from anthesis to maturity stages, SD2 with SR90 had the highest soil water consumption in all three seasons. The highest water consumption in the productive growth period resulted in the best grain yield in both low and high rainfall years. Ear number largely contributed to the seasonal variation in grain yield, while grain number per ear and 1 000-grain weight also contributed to grain yield, especially when soil water storage was high. Our results indicate that sowing date and seeding rate affect grain yield through seedling development before winter and also affect soil water consumption in different growth periods. By selecting the suitable sowing date (1 October) in combination with the proper seeding rate of 90 kg ha–1, the best yield was achieved. Based on these results, we recommend that the current sowing date be delayed from 22 or 23 September to 1 October.

(1) Background: many rare cystic fibrosistransmembrane conductance regulator (CFTR) mutations remain poorly characterized with regard to functional consequences of the mutation. We present the clinical features of two pediatric cystic fibrosis (CF) subjects who are heterozygous for F1099L (c.3297C&gt, G), one with G551D (a class III mutation) and one with 3849 + 10kbC-&gt, T (a class V mutation). We also identified the molecular defect(s) that are associated with F1099L mutation to correlate with the clinical features that we observed, (2) Methods: clinical findings and history were extracted from the electronic medical record and de-identified. F1099L-CFTR protein expression level and maturation status, channel function, and the effects of CFTR modulation on these characteristics were investigated using western blotting and iodide efflux assay, (3) Results: these two subjects have mild CF phenotypes when F1099L is combined with two known disease-causing mutations. F1099L-CFTR has a moderate defect in processing and maturation, causing fewer CFTR channels at the cell surface and, therefore, impaired channel activities. These defects could be effectively corrected using VX-809 (lumacaftor), and, (4) Conclusions: our biochemical data correlate with the disease manifestations and suggest that F1099L is potentially a CF-causing mutation. The study expands our knowledge of rare CFTR mutations and may help in developing effective therapies for subjects with F1099L mutation.

To identify more carbon (C)-friendly agricultural technology, we studied the coupling impact of film mulching during summer fallow and sowing method on carbon footprint (CF) of dryland winter wheat (Triticum aestivum L.) on the Loess Plateau. From 2011 to 2014, a two-factor split block design was conducted with the following treatments: water-permeable film mulching in the summer fallow season (FM) or no mulching in the summer fallow season (FM0) with either conventional drill sowing (DS) or drill sowing beside a common film (DSF). The greenhouse gases (GHG) emissions associated with agricultural inputs were 7013.3, 5908.3, 5298.5, and 4193.5 kg CO2-eq·ha−1·yr−1 for FM × DSF, FM0 × DSF, FM × DS, and FM0 × DS treatments, respectively, which contributed >80% of total GHG emissions during the winter wheat production. Fertilizer, especially P2O5 fertilizer, was the largest contributor to GHG emissions from agricultural inputs. The CF of dryland winter wheat was 1.14 to 3.60 kg CO2-eq kg−1, which was the lowest under the FM × DS treatment while the largest under the FM × DSF treatment. Film mulching during summer fallow with drill sowing (FM × DS) could be a C-friendly technology for winter wheat production on the Loess Plateau.

Fallow tillage methods play a major role in improving soil water storage, water use efficiency and hence grain yield in winter wheat (Triticum aestivum L.) cropping system in southeast Loess Plateau. However, the efficacy and stability of such methods need to be further validated in long-term field observation. From 2009–2015, a 7-year filed experiment was established in winter wheat fields at Wenxi Agriculture Station, semiarid southeast Loess Plateau. The objectives were to determine the responses of soil water storage, utilization and yield formation to three different tillage methods: including deep ploughing, subsoiling and no-tillage. Our results indicated that compared to no-tillage, the soil water storage (0–300 cm depth) was averagely increased by 7.8% and 6.0% during fallow season, 13.7% and 9.8% in growing season under deep ploughing and subsoiling respectively. Furthermore, the increasing magnitude in soil water due to deep ploughing and subsoiling was, on average, 10.1% and 5.5% higher in dry season than that in wet one. Improved soil water condition under deep ploughing and subsoiling significantly increased the ear number and grain yield by 20.2% and 15.9%, 30.8% and 25.8% respectively, but did not affect seed number and weight of thousand seed over the experimental seasons. Moreover, grain yields under deep ploughing and subsoiling were averagely increased by 35.2% and 24.8% in dry season, 28.7% and 20.6% in wet season respectively. Accordingly, water use efficiency and precipitation use efficiency were increased by 12.1% and 31.9% under deep ploughing, 11.1% and 25.0% under subsoiling respectively. Critically, we found that with an increase of 10% water storage efficiency during fallow season, ear number, grain yield and WUE could be increased by 0.2 million ha−1, 241.1 kg ha−1 and 0.6 kg ha−1 mm−1 respectively. Our study clearly indicated that deep ploughing in fallow season should be adopted as a promising strategy to retain soil water availability and hence boost wheat productivity in semiarid southeast Loess Plateau.