14 research outputs found

    Integrated Evaluation to High Yield and Water-saving of Winter Wheat in North China

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    Evaluation to high yield and water-saving for improving water use efficiency (WUE) of crops is becoming important in irrigated farming and dry farming. Field experiments with 7 winter wheat varieties under 2 levels of irrigation were conducted in Luancheng Experiment Station (37 53 LN C140 40 LE G 50m above the sea level) during 2001 to 2002. The growth and development of yield and its components, water use, WUE, photosynthesis rate, transpiration rate and stomata conductance were measured. The results showed that yield and drought resistance index was not significantly related with several measured agronomic traits. However, area of flag leaf and the leaf below flag leaf were significantly negatively related with WUE at yield level, specific leaf weight of flag leaf and the leaf below flag leaf was significantly positive related with WUE at yield level, transpiration rate and stomata conductance were significantly negatively related with WUE at leaf level. Based on leaf water potential ( t µ ), stomata resistance (Rs), transpiration rate (Tr), drought resistance coefficient (DC), maximum yield (Ym) and WUE at yield level, an evaluation index to high-yield, water saving and drought- resistance(IA) was established as follows : IA=0.4Ym + 0.2WUE + 0.1(Rs+ t µ +Tr) + 0.1DC.vokMyynti MTT tietopalvelu

    Root growth, available soil water, and water-use efficiency of winter wheat under different irrigation regimes applied at different growth stages in North China

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    Field experiments were conducted at the Luancheng Agro-Ecosystem Experimental Station of the Chinese Academy of Sciences during the winter wheat growing seasons in 2006-2007 and 2007-2008. Experiments involving winter wheat with 1, 2, and 3 irrigation applications at jointing, heading, or milking were conducted, and the total irrigation water supplied was maintained at 120 mm. The results indicated that irrigation during the later part of the winter wheat growing season and increase in irrigation frequency decreased the available soil water; this result was mainly due to the changes in the vertical distribution of root length density. In 30-cm-deep soil profiles, 1 time irrigation at jointing resulted in the highest root length density. With regard to evapotranspiration (ET), there was no significant (LSD, P Root length density Available soil water Water-use efficiency Winter wheat Deficit irrigation

    Effects of Irrigation and Straw Mulching on Microclimate Characteristics and Water Use Efficiency of Winter Wheat in North Chinas

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    In North China, irrigation is required to obtain a high yield from winter wheat; this results in rapid aquifer depletion. The primary objective of this study was to investigate the influencing mechanisms of irrigation and straw mulching in preserving the soil moisture. Maize straw (3−5 cm) was mulched immediately after sowing winter wheat, and irrigation water was supplied at 60 mm, controlled by using a flow meter, during the jointing, heading, or milking stages of the crop. The results revealed that irrigation decreased the eddy thermal diffusivity, sensible heat flux, and soil heat flux, but increased the latent heat flux. In contrast, straw mulching enhanced the eddy thermal diffusivity and sensible heat flux, but decreased the latent heat flux. Straw mulching increased the soil temperature at 5 cm depth form January to February, but decreased the soil temperature before January and after February. There were no significant differences in the total evapotranspiration between mulched and non-mulched treatments, however, there was a statistically significant difference in the evapotranspiration among the different growing seasons. Straw mulching reduced the evapotranspiration from the seeding stage to the regrowing stage, and the evapotranspiration with mulching was less than that non-mulching 47.4 mm. Further, straw mulching significantly reduced the number of spikes in the crop. Both irrigation and straw mulching increased the number of kernels, but had no visible effects on the thousand kernel weight. These results indicate that straw mulching may decrease the yield and water use efficiency (WUE) of winter wheat in North China

    Effects of irrigation and planting patterns on radiation use efficiency and yield of winter wheat in North China

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    The factor limiting the increase in winter wheat yield was not the deficiency of light radiation but the low radiation use efficiency (RUE). In 2004-2005 and 2005-2006, an experiment was conducted at the Agronomy Station of Shandong Agricultural University to study the effects of irrigation and different planting patterns on the photosynthetic active radiation (PAR) capture ratio, PAR utilization, and winter wheat yield. In this experiment, winter wheat was planted in four patterns as follows: uniform row planting (U; row spacing, 30 cm), "20 + 40" wide-narrow row planting (W), "20 + 40" furrow planting (F), and "20 + 40" bed planting (B), which are very popular in North China. The results showed that under different irrigation regimes, there was no significant difference (less than 15.93%) between any of the planting patterns with respect to the amount of PAR intercepted by the winter wheat canopies. However, significant differences were observed between different planting patterns with respect to the amount of PAR intercepted by plants that were 60-80 cm above the ground surface (53.35-225.16%). This result was mainly due to the changes in the vertical distributions of leaf area index (LAI). As a result, the effects of the planting patterns on RUE and the winter wheat yield were due the vertical distribution of PAR in the winter wheat canopies. During the late winter wheat growing season, irrespective of the applied irrigation, the RUE in case of F was higher than that in case of U, W, and B by 0.05-0.09, 0.04-0.08, and 0.02-0.12 g/mol, respectively, and the yield was higher by 238.39-693.46, 160.02-685.96, and 308.98-699.06 kg/ha, respectively. Only under the fully irrigated conditions, the RUE and winter wheat yield significantly (LSD; P

    Effects of elevated CO2 concentration on growth and water use efficiency of winter wheat under two soil water regimes

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    Winter wheat (Triticum aestivum L. cv. Kenong9204) was grown in open top chambers with either ambient or elevated CO2 concentrations (358 ± 19 [mu]mol mol-1 or 712 ± 22 [mu]mol mol-1, respectively) in well-watered or drought conditions. Although elevated CO2 did not significantly affect the height of the plants at harvest, it significantly increased the aboveground biomass by 10.1% and the root/shoot ratio by 16.0%. Elevated CO2 also significantly increased the grain yield (GY) by 6.7% when well-watered and by 10.4% when drought stressed. Specifically, in the well-watered condition, this increase was due to a greater number of ears (8.7% more) and kernels (8.6). In the drought condition, it was only due to a greater number of spikes (17.1% more). In addition, elevated CO2 also significantly increased the water use efficiency (WUE) of the plants by 9.9% when well-watered and by 13.8% under drought conditions, even though the evapotranspiration (ET) of the plants did not change significantly. Elevated CO2 also significantly increased the root length in the top half of the soil profile by 35.4% when well-watered and by 44.7% under drought conditions. Finally, elevated CO2 significantly increased the root water uptake by 52.9% when well-watered and by 10.1% under drought conditions. These results suggest that (1) future increases in atmospheric CO2 concentration may have a significant effect on wheat production in arid and semiarid areas where wheat cultivation requires upland cropping or deficit irrigation; (2) wheat cultivars can be developed to have more tillers and kernels through selective breeding and field management; and (3) fertilizer and water management in topsoil will become increasingly important as atmospheric CO2 concentration rises.Elevated CO2 concentration Grain yield (GY) Water use efficiency (WUE) Root/shoot ratio (RSR) Root distribution Soil water depletion (SWD)

    Control of Abscisic Acid Catabolism and Abscisic Acid Homeostasis Is Important for Reproductive Stage Stress Tolerance in Cereals1[W][OA]

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    Drought stress at the reproductive stage causes pollen sterility and grain loss in wheat (Triticum aestivum). Drought stress induces abscisic acid (ABA) biosynthesis genes in anthers and ABA accumulation in spikes of drought-sensitive wheat varieties. In contrast, drought-tolerant wheat accumulates lower ABA levels, which correlates with lower ABA biosynthesis and higher ABA catabolic gene expression (ABA 8′-hydroxylase). Wheat TaABA8′OH1 deletion lines accumulate higher spike ABA levels and are more drought sensitive. ABA treatment of the spike mimics the effect of drought, causing high levels of sterility. ABA treatment represses the anther cell wall invertase gene TaIVR1, and drought-tolerant lines appeared to be more sensitive to the effect of ABA. Drought-induced sterility shows similarity to cold-induced sterility in rice (Oryza sativa). In cold-stressed rice, the rate of ABA accumulation was similar in cold-sensitive and cold-tolerant lines during the first 8 h of cold treatment, but in the tolerant line, ABA catabolism reduced ABA levels between 8 and 16 h of cold treatment. The ABA biosynthesis gene encoding 9-cis-epoxycarotenoid dioxygenase in anthers is mainly expressed in parenchyma cells surrounding the vascular bundle of the anther. Transgenic rice lines expressing the wheat TaABA8′OH1 gene under the control of the OsG6B tapetum-specific promoter resulted in reduced anther ABA levels under cold conditions. The transgenic lines showed that anther sink strength (OsINV4) was maintained under cold conditions and that this correlated with improved cold stress tolerance. Our data indicate that ABA and ABA 8′-hydroxylase play an important role in controlling anther ABA homeostasis and reproductive stage abiotic stress tolerance in cereals

    CASTLEMAN DISEASE VARIANT OF POEMS SYNDROME: A CASE REPORT AND LITERATURE REVIEW

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    Objective To improve the awareness of POEMS syndrome among clinicians, and to increase the experience in the clinical diagnosis and treatment of atypical POEMS syndrome. Methods A retrospective analysis was performed for the cli-nical data of a patient with Castleman disease variant of POEMS syndrome who were hospitalized in Department of Endocrinology in our hospital in September 2020, and a literature review was performed. Results The patient had the initial manifestation of endocrine abnormality (hypogonadism), followed by other manifestations such as skin damage, neurogenic damage, multiple serous effusion, and multiple lymph node enlargement, which were consistent with the diagnostic criteria for POEMS syndrome, but hematological examination showed no evidence of clonal plasma cells. After multidisciplinary consultation and lymph node biopsy, pathological examination suggested Castleman disease, with an increase in the level of vascular endothelial growth factor (VEGF) in plasma, and finally the patient was diagnosed with Castleman disease variant of POEMS syndrome. Conclusion Clinicians need to have pluralistic thinking in the diagnosis and treatment of POEMS syndrome, and when POEMS syndrome is highly suspected in clinical practice without fully meeting necessary diagnostic criteria, they should actively look for relevant evidence and emphasize the value of lesion biopsy and plasma VEGF level in the diagnosis of this disease, so as to reduce missed diagnosis and misdiagnosis
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