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Bainong sterility (BNS) is a thermo‐sensitive genic male sterile wheat line, characterised by anther fertility transformation in response to low temperature (LT) stress during meiosis, the failure of vacuole decomposition and the absence of starch accumulation in sterile bicellular pollen. Our study demonstrates that the late microspore (LM) stage marks the transition from the anther growth to anther maturation phase, characterised by the changes in anther structure, carbohydrate metabolism and the main transport pathway of sucrose (Suc). Fructan is a main storage polysaccharide in wheat anther, and its synthesis and remobilisation are crucial for anther development. Moreover, the process of pollen amylogenesis and the fate of the large vacuole in pollen are closely intertwined with fructan synthesis and remobilisation. LT disrupts the normal physiological metabolism of BNS anthers during meiosis, particularly affecting carbohydrate metabolism, thus determining the fate of male gametophytes and pollen abortion. Disruption of fructan synthesis and remobilisation regulation serves as a decisive event that results in anther abortion. Sterile pollen exhibits common traits of pollen starvation and impaired starch accumulation due to the inhibition of apoplastic transport starting from the LM stage, which is regulated by cell wall invertase TaIVR1 and Suc transporter TaSUT1. Summary statement: The manuscript provides new insight into the role of carbohydrate metabolism in regulating anther development and the molecular mechanisms underlying pollen abortion in a thermo‐sensitive genic male sterile winter wheat line under low temperature during meiosis. [ABSTRACT FROM AUTHOR]

Drought is the most important factor limiting winter wheat yield in the North China Plain (NCP). Choosing high-yielding cultivars is an important measure to minimize the negative effects of drought stress. Field studies were conducted with 10 cultivars in the 2020–2022 seasons under three irrigation treatments (I0, without irrigation; I1, irrigated at jointing stage; I2, irrigated at jointing and anthesis stages) in the NCP to examine the water use strategies and root and shoot traits of high-yielding cultivars under different water supply conditions. The results showed that yield variation among cultivars was 21.2–24.6%, 23.7–25.9% and 11.6–15.3% for the I0, I1 and I2 treatments, respectively. Under water deficit conditions (I0 and I1), high-yielding cultivars reduced water use during vegetative stages and increased soil water use during reproductive stages, especially water use from deeper soil layers. Those cultivars with higher root length density (RLD) in deep soil layers exhibited higher water uptake. Each additional millimeter of water used after anthesis from the 100–200 cm soil layers increased grain yield by 23.6–29.6 kg/ha and 16.4–28.5 kg/ha under I0 and I1, respectively. This water use strategy enhanced dry matter accumulation after anthesis, decreased canopy temperature (CT) and increased relative leaf water contents (RLWC), which ultimately improved grain yield. For winter wheat grown under I2, cultivars that decreased water use after anthesis had higher water productivity (WP). Root length (RL), root weight (RW) and root:shoot ratio were each negatively correlated with grain yield, while above-ground biomass was positively correlated with grain yield. Therefore, higher dry matter accumulation and smaller root systems are two important traits of high-yielding cultivars under sufficient water supply conditions (I2) in the NCP. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the effects of irrigation frequency and nitrogen fertilization rate on the abundance, diversity, and composition of soil bacteria in winter wheat. Irrigation, but not nitrogen fertilization, significantly affected the bacterial alpha diversity index. Among the 50 phyla obtained in these treatments, Proteobacteria, Bacteroidetes, Actinobacteria, Acidobacteria, Gemmatimonadetes, and Firmicutes were the predominant phyla. The LEfSe analysis of different treatments indicated that irrigation had a stronger effect on soil bacteria community composition than nitrogen fertilization. Moreover, the soil pH, moisture, available phosphorus (AP), and available potassium (AK) significantly correlated with the relative abundance of dominant bacteria at the phylum, genus, and operational taxonomic unit (OTU) levels. Overall, after three years of irrigation and fertilization treatments, the effect of irrigation on soil bacteria abundance, diversity, and composition of winter wheat was stronger than that of nitrogen fertilization, highlighting the importance of water availability for bacteria communities in semi-arid ecosystems. Inorganic and organic fertilizers should be applied in rotation. [ABSTRACT FROM AUTHOR]

Melatonin is effective in enhancing various abiotic stress resistances of plants. However, its underlying mechanisms in drought-resistance in winter wheat (Triticum aestivum L.) is not clear. The goal of this work was to investigate the effect of melatonin on seed germination and to evaluate leaf antioxidant physiology for two wheat varieties. Experiments included 20% PEG, melatonin plus 20% PEG and a control using two contrasting wheat varieties (JM22– drought sensitive and HG35– drought resistant). Melatonin levels were 0, 1, 10, 100 and 300 μmol L-1. Results revealed that 300 μmol L-1 of melatonin alleviated the negative effect of water stress on germination and increased radicle length, radicle number, and plumule length of the germinated seeds. Principal component analysis showed a significant change in amino acid content during germination and this change was dependent on melatonin concentration and the variety. Lysine (Lys) content in wheat seeds under the PEG plus 300 μmol L-1 melatonin treatment increased compared with that of the seeds under PEG alone. There was a significant and positive correlation between Lys content and morphological index of germination. During seedling growth, soluble protein was involved in osmotic adjustment and superoxide dismutase (SOD) activity was increased to mitigate the damage in the cytomembrane of JM 22 leaf under 300 μmol L-1 melatonin plus PEG treatment. The effect of melatonin was dependent on SOD activity increasing significantly for HG35—a drought resistant variety. The results of this work lays a foundation for further studies to determine if melatonin can be economically used to mitigate the impact of dry planting conditions on wheat productivity in North China Plain. [ABSTRACT FROM AUTHOR]

Regulating plant density is an important practice to improve winter wheat productivity under limited irrigation in North China Plain. Field experiments were carried out over two seasons (2014–15 and 2015–16) under three plant densities (Dh: 480–570, Dm: 360–390, Dl: 240–270 104 plants hm−2) and three irrigation levels (W0: no irrigation; W1: irrigated 80.0 mm only at the jointing stage, which also means limited irrigation; W2: irrigated 60.0 mm each at the jointing and the flowering stages). Results showed that higher numbers of spikes and higher yield were obtained at high density than that at low density under limited irrigation. Under the same irrigation, wheat culms at ripening stage and the proportion of main stem spikes increased with plant density increasing, along with the increasing of transportation amount, transportation rate, and contribution rate of pre-anthesis storage material to grain. But accumulation amount and contribution rate of post-anthesis dry matter, which was influenced by irrigation level, showed a declining trend with increasing plant density under W2 and W1. Therefore, (1) under limited water condition, yield loss could be compensated by increasing contribution rate of pre-anthesis storage material to grain with increasing plant density. (2) Meantime, under the same limited water condition, higher plant densities could promote nitrogen accumulation in grain and plant of wheat, which was significantly correlation to wheat yield. (3) Considering water and nitrogen use efficiency, medium plant density (Dm) is recommended in wet years, high plant density (Dh) may be considered to increase wheat yield in dry years. [ABSTRACT FROM AUTHOR]

Water shortage is becoming the most important limiting factor for wheat production in many regions such as the North China Plain (NCP). The highly intensive production of grain yield to meet food demand has led to serious negative impacts on the environment in this area. The objective of this study was to evaluate the effect of plough tillage (P), subsoiling tillage (S) and rotary tillage (R) on water consumption characteristics, dry matter accumulation and remobilization, grain yield and water use efficiency (WUE) of winter wheat under water saving irrigation (W2), limiting irrigation (W1) and rainfed conditions (W0). The study was carried out at the Gaocheng Experiment Station of Hebei Agricultural University during 2014–2016. The results showed that deep tillage practices (plough tillage and subsoiling) can offset wheat yield reductions under limited irrigation regime. The grain yield with plough tillage under rainfed condition (P0) produced similar yield of 8546 kg ha−1 over two years, which was not significantly different from rotary tillage under water saving condition (R2). The plough tillage gave higher water storage in the 0–200 cm soil layer at the pre-sowing stage of the second winter wheat crop by 67.7%, 64.4% and 39.8% compared to rotary tillage under W2, W1 and W0 conditions, respectively. The soil water consumption and evapotranspiration (ET) with plough tillage and subsoiling were higher than those with rotary tillage under W1 and W0 treatments in both years. Under the W0 treatment, the pre-anthesis dry matter remobilization (DMR), coefficient of pre-anthesis dry matter remobilization (TCDMR) and contribution of pre-anthesis dry matter to grain (CDMR) with plough tillage and subsoiling tillage were lower than those under rotary tillage, but the post-anthesis accumulated dry matter accumulation (ADM) and its accumulated coefficient (ACDM) were higher than those under rotary tillage in both years due to higher soil water consumption. Therefore, deep tillage would be a desirable tillage practice for wheat production under limited irrigation condition. • Effect of tillage practices with three irrigation regimes on wheat production was investigated. • Ploughing and subsoiling can increase soil reservoir capacity to store more summer rainfall. • The decrease of yield by water-saving strategies can partly be compensated by deep tillage. [ABSTRACT FROM AUTHOR]

Under the changing climate, asymmetric warming pattern would be more likely during day and night time, instead of symmetric one. Concurrently, the growth responses and water use of plants may be different compared with those estimated based on symmetric warming. In this work, it was compared with the effects of symmetric ( ETs) and asymmetric ( ETa) elevation of temperature alone, and in interaction with elevated carbon dioxide concentration ( EC), on the grain yield ( GY) and evapotranspiration in winter wheat ( Triticum aestivum L.) based on pot experiment in the North China Plain ( NCP). The experiment was carried out in six enclosed-top chambers with following climate treatments: (1) ambient temperature and ambient CO2 ( CON), (2) ambient temperature and elevated CO2 ( EC), (3) elevated temperature and ambient CO2 ( ETs; ETa), and (4) elevated temperature and elevated CO2 ( ECETs, ECETa). In symmetric warming, temperature was increased by 3°C and in asymmetric one by 3.5°C during night and 2.5°C during daytime, respectively. As a result, GY was in ETa and ETs 15.6 ( P < 0.05) and 10.3% ( P < 0.05) lower than that in CON. In ECETs and ECETa treatments, GY was 14.9 ( P < 0.05) and 9.1% ( P < 0.05) higher than that in CON. Opposite to GY, evapotranspiration was 7.8 ( P < 0.05) and 17.9% ( P < 0.05) higher in ETa and ETs treatments and 7.2 ( P < 0.05) and 2.1% ( P > 0.05) lower in ECETs and ECETa treatments compared with CON. Thus, GY of wheat could be expected to increase under the changing climate with concurrent elevation of CO2 and temperature as a result of increased WUE under the elevated CO2. However, the gain would be lower under ETa than that estimated based on ETs due to higher evapotranspiration. [ABSTRACT FROM AUTHOR]

The intensive use of groundwater and nitrogen fertilizer has led to serious negative impacts on the environment of the North China Plain (NCP). Water footprint is an emerging approach to assess the consumptive water use and the environmental impacts on winter wheat-summer maize systems. A seven-year rotation experiment was conducted to collect data on wheat and maize growth response to nitrogen rates and irrigation schedules and to explore how the water footprint was affected, using DSSAT 4.6 Wheat and Maize crop models. Results showed that the increase in farm inputs contributed greatly to the increase in water footprint, primarily through the grey water footprint. The water footprints of maize and wheat were more sensitive to the nitrogen rate and irrigation, respectively. An irrigation of 160 mm produced a minimum total water footprint and higher yield for wheat. The grey water footprint of maize increased linearly when the nitrogen rate applied to maize exceeded 60 kg ha−1. Water-saving irrigation with 300 kg ha−1 of nitrogen can maintain a higher grain yield and have little impact on the environment. The approach used and the results can help to develop management strategies to maintain high yields while minimizing the water footprint in NCP. [ABSTRACT FROM AUTHOR]

To explore the feasibility of water-saving irrigation measures based on long-term positioning experiments on winter wheat (Triticum aestivum L.) under different irrigation and nitrogen application treatments, the main factors influencing the effect of supplementary irrigation at the anthesis stage on yield increase were explored in Gaocheng and Qingyuan, China. The experiment was designed as a split-plot arrangement, with the irrigation type as the main plot and nitrogen application rate as the sub-plots. The irrigation treatments consisted of two levels based on the amount of irrigation: 60 mm at the jointing stage (W1) and 60 mm at the jointing and anthesis stages, respectively (W2). The nitrogen treatments consisted of three levels: 0 (N0), 120 (N120), and 240 kg ha−1 (N240). Over time, the soil organic matter and total nitrogen content of N0 decreased significantly, resulting in a gradual increase in the difference between the yield increase effect of N0 and that of the nitrogen application treatment. The effect of supplementary irrigation on winter wheat yield at the anthesis stage was significantly affected by soil water storage (SWS) before sowing. The smaller the soil water storage before sowing, the larger the yield increase ratio with supplementary irrigation at the anthesis stage. The yield increase due to supplementary irrigation at the anthesis stage was also affected by precipitation during the winter wheat growth period, particularly from the jointing stage to the anthesis stage. When the precipitation from the jointing stage to the anthesis stage was < 31.9 mm, the yield increase from supplementary irrigation at the anthesis stage was significant. The results indicated that in the case of sufficient SWS before sowing, 31.9 mm of precipitation from the jointing stage to the anthesis stage could be used as a reference value for irrigation at the anthesis stage. • Excessive soil water storage reduced the yield-increasing ratio. • Insufficient soil nitrogen reduced the yield-increasing ratio. • The precipitation had a great influence on the yield increase effect. • The precipitation of 31.89 mm was an important dividing line for the yield-increasing ratio. [ABSTRACT FROM AUTHOR]

Irrigation and nitrogen application can not only increase wheat yield, but also cause nitrogen loss and soil nitrate accumulation. This study aimed to assess the effects of irrigation amount and nitrogen application rate on the soil NO 3 --N distribution and nitrogen absorption and utilization of winter wheat (Triticum aestivum L.) during the 2015–2020 growth season in the North China Plain. The experiments were designed in split plot arrangement, with irrigation amount (W0, no irrigation; W1, 60 mm irrigation at jointing; and W2, 60 mm irrigation at jointing and anthesis) as the main plots and nitrogen application rate (N0, 0; N120, 120 kg ha−1; and N240, 240 kg ha−1) as the subplots. The plants under W2N120 and W2N240 showed no significant difference in yield throughout the experimental period. With the decrease in soil total nitrogen content, the yield difference between the plants under N0 and those under N120 and N240 gradually increased throughout the experimental period. Compared with that of the plants under W2N240, the mean NO 3 --N content of the plants under W2N120 in the 0–1 m and 1–2 m soil layers decreased by 17.4% and 19.2%, respectively, in 2018–2020. The NO 3 --N concentration decreased with increasing soil depth, and the NO 3 --N concentration in each soil layer increased with increasing nitrogen application rate. Irrigation and nitrogen application increased nitrogen accumulation in vegetative organs at anthesis and nitrogen transport to grains. Compared with those of the plants under W2N240, the mean nitrogen uptake efficiency, nitrogen use efficiency, nitrogen fertilizer productivity, and nitrogen harvest index of the plants under W2N120 increased by 91.3%, 2.6%, 95.5%, and 1.9%, respectively. These results suggest that applying 120 kg ha−1 nitrogen and irrigating 60 mm at jointing and anthesis are the optimal measures for winter wheat in the North China Plain. • The effect of no nitrogen application on yield increased year by year. • Applying 240 kg ha−1 nitrogen significantly increased the accumulation of NO 3 --N in soil. • Applying 120 kg ha−1 nitrogen can achieve high yield and better nitrogen utilization. • Irrigating 60 mm at jointing and anthesis is an optimal measure. [ABSTRACT FROM AUTHOR]