ABSTRACT: Chilling depresses seed germination and seedling establishment, and is one major constraint to grain yield formation in late sown winter wheat. Seeds of winter wheat (Triticum aestivum L.) were separately pre-soaked with sodium nitroprusside (SNP, as nitric oxide donor) and Gibberellic acid (GA3) before germination and then germinated under low temperature. SNP and GA3 pre-treatment increased seed germination rate, germination index, weights and lengths of coleoptile and radicle, while decreased mean germination time and weight of seed germinating under low temperature. Exogenous NO and GA3 improved seed respiration rate and promoted starch degradation along with increased amylase activities. In addition, efficient antioxidant systems were activated by NO due to regulate activities of superoxide dismutase (SOD, EC 126.96.36.199) and peroxidase (POD, EC 188.8.131.52), and expressions of SOD and POD encoding genes in germinating seeds, which contributed to reduced concentrations of malondialdehyde (MDA) and hydrogen peroxide (H2O2) and hence improved seed germination rate under chilling stress. Furthermore, seedling growth was improved by exogenous NO and GA3 as a result of improved seed germination and maintenance of better ROS homeostasis in seedling growing under chilling. It is indicated that exogenous NO was more effective than GA3 in alleviating chilling stress on seed germination and seedling establishment in wheat.
Plant Growth Regulation 03/2013; · 1.60 Impact Factor
Journal of Cereal Science 01/2013; 57:134-140. · 2.07 Impact Factor
ABSTRACT: Various sensors have been used to obtain the canopy spectral reflectance for monitoring above-ground plant nitrogen (N) uptake in winter wheat. Comparison and intercalibration of spectral reflectance and vegetation indices derived from different sensors are important for multi-sensor data fusion and utilization. In this study, the spectral reflectance and its derived vegetation indices from three ground-based sensors (ASD Field Spec Pro spectrometer, CropScan MSR 16 and GreenSeeker RT 100) in six winter wheat field experiments were compared. Then, the best sensor (ASD) and its normalized difference vegetation index (NDVI (807, 736)) for estimating above-ground plant N uptake were determined (R2 of 0.885 and RMSE of 1.440 g·N·m-2 for model calibration). In order to better utilize the spectral reflectance from the three sensors, intercalibration models for vegetation indices based on different sensors were developed. The results indicated that the vegetation indices from different sensors could be intercalibrated, which should promote application of data fusion and make monitoring of above-ground plant N uptake more precise and accurate.
Sensors 01/2013; 13(3):3109-30. · 1.74 Impact Factor
ABSTRACT: Cadmium (Cd) tolerance and accumulation in wheat varieties were investigated at seedling stage under a controlled environmental
condition. The 46 leading wheat varieties cultivated from the 1950s to 2000s in China were treated at the three-leaf stage
with a 50μM CdCl2 solution for 24days. Growth and photosynthesis parameters were measured and the Cd-tolerance index (ratio of a given parameter
under Cd treatment to that of the control) was determined. Cd accumulation in shoots and roots and Cd translocation were also
determined. It was found that Cd tolerance and accumulation of these wheat varieties varied over the different decades. Principal
components analysis (PCA) showed that wheat varieties in 1950s and 1980s were tolerant while varieties from the last decade
were sensitive to Cd stress. Wheat varieties in 1960s and 1970s were particularly tolerant to Cd stress for the parameters
of shoot height, secondary root numbers, net photosynthesis and transpiration rate while the varieties in the 1990s were sensitive
to Cd stress for shoot dry weight and root dry weight. Comparing each decade to the average Cd translocation ratio from the
roots to the shoots for the whole period, the varieties from the 1950s and 1960s had a higher translocation ratio, while varieties
in the 1970s were below that average. Varieties from the 1980s to 2000s showed an average translocation ratio. Using cluster
analysis (CA), Shannongfu 63, Yangmai 1 and Yangmai 158 were the most Cd-tolerant varieties in which Cd translocation ratio
were low, and Yumai 18 and Huaimai 20 were the most Cd-sensitive varieties in which Cd translocation ratio were high. The
results indicating that wheat varieties from different decades were different in Cd tolerance and accumulation, and could
be useful for breeding wheat for Cd stress tolerance.
KeywordsCadmium–Wheat–Tolerant index–Translocation–Principal component analysis–Cluster analysis
Acta Physiologiae Plantarum 04/2012; 33(5):1811-1819. · 1.64 Impact Factor
ABSTRACT: Waterlogging is predicted to increase in both magnitude and frequency along with global warming, and will become one of the
most severe adversities for crop production in many regions. Nitrogen is considered to be an effective up-regulatory nutrient
for crops grown under stress and non-stress conditions. In this study, we try to evaluate N fertiliser effects on contents
of carbohydrate and N dynamics, dry matter accumulation in shoot, yield under post-anthesis waterlogging. Waterlogging after
anthesis significantly reduced grain yield due to decrease in thousand-kernel-weight and in grain number per spike. High N
fertiliser application aggravated grain yield loss due to post-anthesis waterlogging. These yield losses were related to the
decreases in dry matter accumulation, redistribution of stored photosynthate to the grain, and the conversion capacity from
carbohydrate to starch in grain. The decrease in dry matter accumulation could be attributed to the reduced activities of
Pn (photosynthesis) and SPS (sucrose phosphate synthase) in the flag leaf, while the low capacity in starch synthesis could
be explained by the reduced activities of sucrose synthase (SS) and soluble starch synthase (SSS) in grain. Total N uptake
in shoot was also reduced, which could contribute to the losses in biomass and yield by waterlogging. The decrease in Pn was
inconsistent with the increase in N content in the flag leaf at high N fertiliser application under post-anthesis waterlogging.
Plant and Soil 04/2012; 304(1):301-314. · 2.73 Impact Factor
ABSTRACT: Seedlings of wheat (Triticum aestivum L.) cultivars Jing 411, Jinmai 30 and Yangmai 10 were exposed to 0, 10, 20, 30, 40 or 50μM of CdCl2 in a solution culture experiment. The effects of cadmium (Cd) stress on wheat growth, leaf photon energy conversion, gas
exchange, and Cd accumulation in wheat seedlings were investigated. Gas exchange was monitored at 3, 9, 24days after treatment
(DAT). Growth parameters, chlorophyll content, leaf chlorophyll fluorescence, and Cd concentration in shoot and root were
measured at 24DAT. Seedling growth, gas exchange, chlorophyll content, chlorophyll fluorescence parameters were generally
depressed by Cd stress, especially under the high Cd concentrations. Cd concentration and accumulation in both shoots and
roots increased with increasing external Cd concentrations. Relationships between corrected parameters of growth, photosynthesis
and fluorescence and corrected Cd concentrations in shoots and roots could be explained by the regression model Y=K/(1+exp(a+bX)). Jing 411 was found to be Cd tolerant considering parameters of chlorophyll content, photosynthesis and chlorophyll fluorescence
in which less Cd translocation was from roots into shoots. The high Cd concentrations were in shoots and roots in Yangmai
10 which has been found to be a relative Cd tolerant cultivar in terms of most growth parameters.
KeywordsCadmium stress-Gas exchange-Chlorophyll fluorescence-Growth-Regression model-Wheat
Acta Physiologiae Plantarum 04/2012; 32(2):365-373. · 1.64 Impact Factor
ABSTRACT: Protein concentration of grain is an important quality index of rice, and formation of grain protein largely depends on pre-anthesis
nitrogen assimilation and post-anthesis nitrogen remobilization in the rice plant. The primary objective of this study was
to develop a simplified process model for simulating nitrogen accumulation and remobilization in plant and protein formation
in rice grains on the basis of an established rice growth model. Six field experiments, involving different years, eco-sites,
varieties, nitrogen rates, and irrigation regimes, were conducted to obtain the necessary data for model building, genotypic
parameter determination, and model validation. Using physiological development time (PDT) as general time scale of development progress and cultivar-specific grain protein concentration as genotypic parameter,
the dynamic relationships of plant nitrogen accumulation and translocation to environmental and genetic factors were quantified
and synthesized in the present model. The pre-anthesis nitrogen uptake rate by plant changed with the PDT in a negative exponential pattern, and post-anthesis nitrogen uptake rate changed with leaf area index (LAI) in an exponential equation. Post-anthesis nitrogen translocation rate depended on the plant nitrogen concentration and dry
weight at anthesis as well as residue nitrogen concentration of plant at maturity. The nitrogen for protein synthesis in grains
came from two sources: the nitrogen pre-stored in leaves, stem and sheath before anthesis and then remobilized after anthesis,
and the nitrogen absorbed directly by plant after anthesis. Finally, the model was tested by using the data sets of different
years, eco-sites, varieties, and N fertilization and irrigation conditions with the root mean square errors (RMSE) 0.22%–0.26%, indicating the general and reliable features of the model. It is hoped that by properly integrating with the
existing rice growth models, the present model can be used for predicting grain protein concentration and grain protein yield
of rice under various environments and genotypes.
Frontiers of Agriculture in China 04/2012; 1(1):8-16.
ABSTRACT: A growth model-based decision support system for crop management (GMDSSCM) was developed, which integrates process-based models
of four different crops—wheat, rice, rape and cotton—and realized decision support function, thus facilitating the simulation
and application of the crop models for different purposes. The individual models include six sub models for simulating phase
development, organ formation, biomass production, yield and quality formation, soil-crop water relations and nutrient (N,
P, K) balance. The implemented system can be used for evaluating individual and comprehensive management strategies based
on the results of crop growth simulation under various environments and different genotypes. A stand-alone edition (GMDSSCMA) was established on VC++ and VB platforms by adopting the characteristics of object-oriented and component-based software
and with the effective integration and coupling of the growth prediction and decision-making functions. A web-based system
(GMDSSCMW) was then further developed on the.net platform using C# language. These GMDSSCM systems have realized dynamic prediction
of crop growth and decision making on cultural management, and thus should be helpful for the construction and application
of informational and digital farming system.
Frontiers of Agriculture in China 04/2012; 1(3):296-300.
ABSTRACT: High temperature is a major factor affecting grain yield and plant senescence in wheat growing regions of central and east
China. In this study, two different wheat cultivars, Yangmai 9 with low-grain protein concentration and Xuzhou 26 with high-grain
protein concentration, were exposed to different temperature regimes in growth chambers during grain filling. Four day/night
temperature regimes of 34°C/22°C, 32°C/24°C, 26°C/14°C, and 24°C/16°C were established to obtain two daily temperatures of
28 and 20°C, and two diurnal day/night temperature differences of 12 and 8°C. Concentration of a lipid peroxidation product
malondialdehyde (MDA), activities of the antioxidants superoxide dismutase (SOD) and catalase (CAT), chlorophyll concentration
(SPAD) in flag leaves and kernel weight were determined. Results show that activities of SOD and CAT in leaves increased markedly
on 14days after anthesis (DAA) for the high-temperature treatment (34°C/22°C) and then declined. As a result, MDA concentration
in leaves increased significantly under high temperature (34°C/22°C and 32°C/24°C). Compared with optimum temperature treatment,
high temperature reduced the concentration of soluble protein and SPAD values in flag leaves. Grain-filling rate increased
slightly initially, but decreased significantly during late grain filling under high temperature. As a result, final grain
weight was reduced markedly under high temperature. Decreases in the activities of SOD and CAT and increases in MDA concentration
in leaves were more pronounced with a 12°C of day/night temperature difference when under high temperatures. Kernel weight
was higher under 12°C of day/night temperature difference under optimum temperatures (24°C/16°C and 26°C/14°C). The responses
to high-temperature regimes appeared to differ between the two wheat cultivars with different grain protein concentrations.
It is concluded that a larger diurnal temperature difference hastened the senescence of flag leaves under high-temperature
conditions, but retarded senescence under optimum temperature treatments of 26°C/14°C and 24°C/16°C.
Plant Growth Regulation 04/2012; 51(2):149-158. · 1.60 Impact Factor
ABSTRACT: Three experiments of in vitro ear culture were conducted to evaluate how the substrates of C (carbon) and N (nitrogen) supply in liquid medium regulate
the grain growth and synthesis of protein and starch in two winter wheat cultivars. Increasing glutamine supply with constant
sucrose concentration increased the contents of total protein and protein components of albumin and globulin in grain, and
the activity of glutamate pyruvate transaminase (GPT) across most treatments, while markedly reducing the contents of total
starch and components of amylose and amylopectin as well as the activities of soluble starch synthase (SSS) and granule bounded
starch synthase (GBSS). The opposite patterns were observed in the experiment of increasing sucrose supply at constant glutamine
concentration. When simultaneously increasing sucrose and glutamine supply at constant ratio, the contents of total protein,
albumin and globulin in grain were slowly enhanced, whereas the contents of total starch, amylose and amylopectin and the
activities of SSS, GBSS and GPT increased only to a certain extent and then decreased. Negative correlations were found between
the contents of protein or protein components in grains and the relative ratio of sucrose to glutamine concentrations in the
culture medium, while positive correlations were seen between the contents of total starch or starch components and the ratio
of sucrose to glutamine. These results implied that the composition of protein and starch in wheat grain could be readily
manipulated by varying the concentrations of sucrose and glutamine and their ratio in the culture medium.
Plant Growth Regulation 04/2012; 48(3):247-259. · 1.60 Impact Factor
ABSTRACT: BACKGROUND: Concentrations of high-molecular-weight glutenin subunits and macropolymers in wheat grains are important indicators of grain quality, which are genetically determined and affected by environmental factors. The 6 VS·6AL translocation chromosome segment is reported to own high powdery mildew and yellow rust resistance genes of Pm21 and Yr26. This study investigated the variation in concentrations of high-molecular-weight glutenin subunits (HMW-GS) and glutenin macropolymer (GMP) in response to the 6 VS·6AL translocation segment and the two contrasting sites. RESULTS: Large variations in concentrations of HMW-GS and GMP were observed within lines containing different HMW-GS compositions and between the contrasting eco-sites. However, 6 VS·6AL chromosome translocation segment showed no significant effects on concentrations of HMW-GS and GMP. In addition, HMW-GS concentration was also found to be significantly correlated with the GMP concentration. CONCLUSION: Concentrations of HMW-GS and GMP are largely affected by the eco-sites and the composition of HMW-GS, whilst not by the presence of 6 VS·6AL chromosome segment translocation. The 6 VS·6AL translocation is suggested as potential donor for breeding wheat cultivars for high resistence to powdery mildew and yellow rust with less risk of undesirable effects on grain quality.
Journal of the Science of Food and Agriculture 01/2012; 92:2188-2194. · 1.44 Impact Factor
ABSTRACT: In order to identify the variation of cadmium (Cd) tolerance and accumulation in wheat (Triticum aestivum L.), a study was conducted in hydroponic culture with or without Cd using recombinant inbred lines (RILs) consisting of 103 RILs derived from a cross of Chuan 35050 × Shannong 483 at seedling stage. The parameters of shoot height, secondary roots numbers, tiller numbers, shoot dry weights, root dry weights, and maximum efficiency of photosystem II photochemistry under dark-adopted conditions were measured. Cd-tolerant indexes were then calculated as relative the above traits under Cd stress to those under the control. Cd concentration in shoot or root was determined and Cd accumulation and translocation were calculated. Based on the Cd-tolerant indexes, membership function analysis was used to determine the variation of the above parameters. The results showed a continuous distribution among the RILs and then the RILs were divided into five groups according to their tolerance. Lines 76 and 17 were considered as the most Cd-tolerant lines while lines 103 and 51 were as the most Cd-sensitive lines. Meanwhile, lines 38 and 79 were with minimum Cd translocation ratio while lines 88 and 53 were with maximum Cd translocation ratio, respectively. The relationship between Cd tolerance and accumulation was not significant, indicating Cd tolerance and accumulation may be independent traits in the RILs. Thus, lines with high Cd tolerance and less Cd accumulation could be selected for wheat breeding.
Biological trace element research 09/2011; 142(3):807-18. · 1.92 Impact Factor
Acta Agriculturae Scandinavica - Section B Soil and Plant Science 07/2011; 61(5):410-420.
ABSTRACT: The interaction of multiple waterlogging events during vegetative growth (at the seven- and nine-leaf stage, and at heading) to a waterlogging event during the generative growth stage was studied in wheat (Triticum aestivum L. cv. Yangmai 9). Waterlogging before anthesis was found to effectively enhance tolerance to a waterlogging event after anthesis, as indicated by: (1) increasing net photosynthetsis (P(N)), stomatal conductance (g(s)) and transpiration (Tr) and maintaining high SPAD (soil plant analysis development) values; (2) enhancing use-efficiency of absorbed light energy in the stressed plants due to high maximum and actual quantum yield (F(v)/F(m), Φ(PSII)); (3) increasing activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT); (4) enhancing dry matter accumulation after anthesis and its contribution to grain mass, which further resulting in significantly improved grain yields. The results indicate that hardening by waterlogging applied before anthesis can effectively improve the tolerance of wheat to waterlogging events occurring during the generative growth stage.
Plant Science 05/2011; 180(5):672-8. · 2.94 Impact Factor
ABSTRACT: The objective of this study was to investigate the effect of pre-anthesis high-temperature acclimation on leaf physiology of winter wheat in response to post-anthesis heat stress. The results showed that both pre- and post-anthesis heat stresses significantly depressed flag leaf photosynthesis and enhanced cell membrane peroxidation, as exemplified by increased O₂⁻(·) production rate and reduction in activities of antioxiditave enzymes. However, under post-anthesis heat stress, plants with pre-anthesis high-temperature acclimation (HH) showed much higher photosynthetic rates than those without pre-anthesis high-temperature acclimation (CH). Leaves of HH plants exhibited a higher Chl a/b ratio and lower chlorophyll/carotenoid ratio and superoxide anion radical release rate compared with those of the CH plants. In addition, antioxidant enzyme activities in HH plants were significantly higher than in CH. Coincidently, expressions of photosythesis-responsive gene encoding Rubisco activase B (RcaB) and antioxidant enzyme-related genes encoding mitochondrial manganese superoxide dismutase (Mn-SOD), chloroplastic Cu/Zn superoxide dismutase (Cu/Zn-SOD), catalase (CAT) and cytosolic glutathione reductase (GR) were all up-regulated under HH, whereas a gene encoding a major chlorophyll a/b-binding protein (Cab) was up-regulated by post-anthesis heat stress at 10 DAA, but was down-regulated at 13 DAA. The changes in the expression levels of the HH plants were more pronounced than those for the CH. Collectively, the results indicated that pre-anthesis high-temperature acclimation could effectively alleviate the photosynthetic and oxidative damage caused by post-anthesis heat stress in wheat flag leaves, which was partially attributable to modifications in the expression of the photosythesis-responsive and antioxidant enzymes-related genes.
Journal of plant physiology 04/2011; 168(6):585-93. · 2.50 Impact Factor
Int. J. Applied Earth Observation and Geoinformation. 01/2010; 12:89-100.
ABSTRACT: Four wheat (Triticum aestivum L.) lines differing in cadmium (Cd) tolerance previously identified from a recombinant inbred line population were subjected to 50 microM CdCl2 from the three-leaf stage for 24 d, to investigate the responses of wheat seedlings to Cd toxicity. Under Cd stress, most growth parameters and root morphological traits were reduced, except for secondary root numbers and average root diameter. Cd enhanced leaf cell peroxidation due to increased malondialdehyde (MDA) content and reduced activities of superoxide dismutase (SOD) and catalase (CAT) in leaves. In addition, CAT activity decreased in the Cd-sensitive lines while increased in the tolerant lines. Leaf photosystem II (PSII) was damaged, since the maximum efficiency of PSII photochemistry (Fv/Fm) and potential efficiency of PSII photochemistry under dark-adapted (Fv/Fo) decreased, while the initial fluorescence (Fo) increased in all lines under Cd stress. Then, total soluble sugar concentration decreased while free amino acids concentration increased in both shoot and root. We concluded that Cd-tolerant lines accumulated less Cd in plant and contained low Cd concentration in shoot (less translocation of Cd to shoot), maintained higher CAT activity in leaf and higher PS II function than the Cd-sensitive lines under Cd toxicity, thus could be related to their tolerant capacity to Cd in the present study.
Chemosphere 09/2009; 77(11):1620-5. · 3.21 Impact Factor