Plant architecture is one of the key factors related to lodging resistance and yield. The dwarf and compact plant architecture has substantial significance in accelerating the yield of rapeseed. The new dwarf line DW871 had more advantages than the wild type rapeseed in marked characterizations, including the similar inflorescence growth characteristics and flowering habits with the cabbage, the straight inflorescences or branches during the whole development stages, short branches, high density of siliques, rigid stems, compact plant type and lodging resistance, and so on. In this study, the inheritance of plant height was analyzed in the different gene rations selected from the crosses between the parent DW871 and other accessions, which were further identified by other marked traits. The results showed that the plant height of DW871 showed the typical quality trait characterization, which was determined by one dominant gene with no cytoplasmic effects. In addition, the plant height of DW871 was affected by modifier gene and conformed to the quantitative traits characteristics. The line SW871 provided the novel rape germplasm resources for selecting the semi-dwarf rapeseed cultivars suitable for mechanized harvesting and simplified planting.
Due to low content of sulfur containing amino acid in soybean, understanding of cystathionine gamma-synthase coding gene GmCGS which plays a key role in synthesis of methionine, at transcriptional level is important to solving this problem. In this study, the transcriptional level of CGS in Transgenic soybean lines overexpressing AtD-CGS and wild type (WT) was detected after sulfate or methionine treatment designed to identify their effects on regulating the expression of GmCGS. After treated with 4.5 mmol/L sulfate, the relative expression level of GmCGS was significantly increased in WT, whereas the transcription level of GmCGS in transgenic lines overexpressing AtD-CGS was significantly decreased. No significant difference was observed after methionine treatment. Compared to WT, the transcriptional level of GmCGS was significantly decreased in transgenic lines. The results indicated that the effect of cultivation technique on expression of GmCGS was too limited to improve methionine content. All of these provided reference for increasing content of Met in soybean.
In this study, the QTLs conferring the resistance to Fusarium wilt were mapped with F2 populations derived from YC2 × YF1 resistant and susceptible combination under 2 environments in castor. Genetic analysis presented a continuous skewness distribution in populations, tending to resistant parent. 5 QTLs were identified in 2014, explained 18.21% of phenotype variation, with a single locus contribution rate of 0.05%-12.32%. Dynamic mapping was performed at 5 stages including 20d, 30d, 40d after seedling, squaring stage and milk ripening period in 2015, and 4, 12, 13, 4 and 1 QTLs were detected respectively, with a single locus contribution rate of 1.64%-21.91%. 1, 3 and 6 QTLs were identified simultaneously at 4, 3 and 2 stages respectively. The detected QTLs at these 5 stages were mainly concentrated on linkage group 3, 4 and 8. One QTL located on linkage group 8 was detected simultaneously in both environments at the same stage. The above results could facilitate the molecular marker assisted selection of Fusarium wilt resistance in castor.
Keywords: Ricinus communis L.; Fusarium wilt; resistance; QTL mapping
In order to study the role of JcACO1 gene in stress resistance of Jatropha curcas, the full-length coding frame sequence of ACO1 gene, named JcACO1(1-aminocyclopropane-1-carboxylic acid oxidase), was cloned for the first time based on the genome database of J. curcas , and its functional domain, phylogenetic evolution, gene structure and low-temperature expression characteristics were analyzed. The results showed that the length of the cloned JcACO1 gene was 1 022 bp, encoded 319 amino acids with the molecular weight of 36.04 kDa and the pI value of 5.50. Sequence alignment demonstrated that JcACO1 was highly conserved in the middle of the sequence and had a conserved domain of Pcbc superfamily. Phylogenetic tree analysis showed that the JcACO1 had high homology with Populus trichocarpa, Hevea brasiliensis and Manihot esculenta. qRT-PCR analysis revealed that Jatropha curcas seeding JcACO1 expressed in different organs, with abundant expression in leaves and stems, but scarcely in roots. In addition, JcACO1 gene was induced by hypothermia in all three organs, and the highest expression of JcACO1gene was observed in roots and stems at 24h of low temperature stress. The results showed that the expression of JcACO1 gene was increased in response to chilling stress.
To quantitively describe and analyze the influences of adjustment of planting structure and change of main traits on the yield of rapeseed (Brassica napus L.), we studied and analyzed the data of a variety selection experiment, which included 168 sets of data of yields and other traits in 10 continuous years (2007-2016), with the structure equation model (SEM). A significance analysis was also conducted on the relative traits and yields of rapeseed under different densities investigated in this study. The result showed that yield per plant reduced significantly with the increase of planting density. Yield per plant was mainly influenced by the number of effective pods per plant. However, the total yield increased with the increase of planting density. The traits investigated in this study showed different levels of total effects on yield per plant as: effective pods per plant > branches > 1000-kernel dry weight > effective pods of main inflorescence > effective length of main inflorescence > seeds per pod. Thus, in order to increase the total yield of rapeseed, we should cultivate cultivars that are more density tolerant and suitable for their environment. At the same time, rapeseed cultivars with more effective pods and branches per plant should be bred to stabilize the total yield.
To explore the popularization value of sparse transplanting of rapeseed in mountain area of Enshi, Hubei Province, effects of 3 different planting methods on yield and economic benefits were studied using two rapeseed cultivars of Zhongyouza 12 and Yangguang 2009. The 3 planting methods were sparse-transplanting (D1, 1.2×104plants/hm2), conventional transplanting (D2, 12×104plants/hm2) and condensed planting (D3, 37.5×104 plants/hm2). Results showed that D1 treatment significantly increased the number of effective branches, plant height and stem diameter. These factors constituted a biological basis for high yield. Among the yield components, plant pod number showed the most significant difference. In D1, it was more than 3 000, 250-285 in D2, and 130-150 in D3. The yield in D1 was 31.27% and 26.63% higher than those of D2 and D3 respectively. The average yield in D1 was above 3 000 kg/hm2. Results also showed that the labor cost of D1 was 39.5/hm2 and 42.5/hm2 less than those of D2 and D3 respectively. Therefore the economic benefits increased by 7 543.55 yuan /hm2 and 5 535.73 yuan /hm2 respectively. D1 treatment significantly increased the input-output ratio. It suggested that sparse-transplanting reduced production costs and increased economic benefits in mountain area.
Using a common Brassica napus L. variety as materials, a pot experiment was carried out to study the spectral response of Brassica napus L. leaves to cadmium pollution with six cadmium pollution treatments (cadmium concentration gradient)，and a preliminary prediction model for cadmium content in leaves was established. The variation of the reflectance spectra of leaves was described by spectral angle, the results showed that sensitive bands of the reflected spectra were distributed in the whole-band 350-2500nm, and the variation of the pigment 350-716 nm and leaves structure 717-975 nm were more obvious than others. After correlation analysis between derivative spectral data, trilateral parameters and cadmium content, the sensitive bands were decided. According to these sensitive parameters，multivariable linear regression models to estimate the cadmium content in leaves were established． The results of the model precision test showed that cadmium content estimation model established by first derivative spectral data were better than others, whose R2 and RMSE were 0.899 and 7.532, respectively. The results indicated that Brassica napus L. could be used as an indicator crop of cadmium pollution, which provided a scientific basis for rapid, accurate and nondestructive detection of cadmium pollution in leaves by hyperspectral technique.
To elucidate the role of phenolic acids in the formation of continuous cropping obstacles in peanuts, ecological effects of cinnamic acid, phthalic acid, p-hydroxybenzoic acid and their mixtures with 4 different concentrations on soil were studied in indoor simulation culture in order to exclude the interference from field factors. The results showed that when the initial content of allelochemicals was low (15 mg·kg-1), the soil microbial biomass carbon and nitrogen, microbial activity, enzyme activities (urease, neutral phosphatase, sucrase, polyphenol oxidase, and catalase) and nutrient contents (alkali-hydrolyzable nitrogen, available phosphorus, and available potassium) in all treatments were slightly higher than those in the control, without significance （P>0.05）. When the initial content of allelochemicals was 30 mg·kg-1 or more, all studied indicators were decreased with the increases of treatment concentration. The mixture of these 3 phenolic acids had the strongest allelopathic effect. Overall, with the extension of cultivation time, the allelopathic inhibition of phenolic acids increased first and then weakened. The strongest allelopathic inhibiton effect of p-hydroxybenzoic acid was on the 7th day, while that of cinnamic acid, phthalic acid and the mixture of the three phenolic acids was on the 15th day. it was assumed that the accumulation of phenolic acids was directly related to the deterioration of the micro-ecological environment of continuous cropping peanuts, which was one of the important factors for the formation of peanut continuous cropping obstacle.
Keywords：phenolic acids; allelochemicals; soil microbial biomass; soil enzyme; soil nutrients；peanut; continuous cropping obstacle
Two soybean (Glycine max) varieties Xudou 18 (waterlogging-sensitive) and Nannong 1138-2 (waterlogging-tolerant) were used to study the regulation effect of spraying sodium diethyldithiocarbamate (DDTC) on photosynthetic indexes, activities of sucrose-metabolizing enzymes of leaves and contents of carbohydrates in leaves, roots and nodules. The results showed that waterlogging stress resulted in an obvious decrease in shoot dry weight, root dry weight and nodule dry weight of soybean plants, net photosynthetic rate (Pn), stomatal conductance (gs), intercellular CO2 concentration (Ci), transpiration rate (Tr) of leaves, starch content of roots and sucrose and starch contents of nodules. Nannong 1138-2 had smaller decrease in plant dry weight, gas exchange parameters and starch content of roots than Xudou 18, while there was a similar change in sucrose and starch contents of nodules between two varieties. Conversely, waterlogging stress significantly increased sucrose phosphate synthetase (SPS), sucrose synthetase (SS) (synthesis), SS (cleavage) and acid invertase (AI) activities and solube sugars, sucrose and starch contents of leaves, and solube sugars and sucrose contents of roots. (?) Nannong 1138-2 exhibited smaller increase in activities of SS (cleavage), AI and concentrations of solube sugars, sucrose and starch of leaves, but a greater increase in SPS and SS (synthesis) activities of leaves. DDTC treatment increased plant dry weight of two varieties under waterlogging stress, and thus alleviated the growth inhibition of waterlogging stress on soybean plants. DDTC treatment increased gas exchange parameters of leaves, the activities of SPS and SS (synthesis) and decreased the activity of SS (cleavage) of leaves, and further improving the transportation of sucrose from leaves to roots and nodules under waterlogging stress. In addition, DDTC treatment increased soluble sugars, sucrose and starch contents of roots and sucrose and starch contents of nodules, indicating that DDTC treatment played an important role in the regulation of growth and physiological process of carbon metabolism of soybean plants under waterlogging stress.
To explore the differences of Mo utilization efficient between high Mo accumulation and low Mo accumulation cultivars, we analyzed the physiological differences of photosynthetic carbon and nitrogen metabolism between high-Mo-accumulation and low-Mo-accumulation soybean cultivars. The results indicated that chlorophyll content, Pn, soluble sugar and shoot dry matter decreased under Mo deficient condition. Under Mo deficient condition, the chlorophyll content, Pn, soluble sugar in 1301 were significantly higher than those in 1304. These results suggested that 1301 (Mo-efficient cultivar) exhibited higher carbon metabolism ability. Meanwhile, the nitrate content and nitrate/ ammonium ratio increased under Mo deficient condition, and NR, GOGAT, GS activity and NH4+-N content decreased under Mo deficient condition. Under Mo deficient condition, NR activity was significantly higher in 1301 than that in 1304, which indicated 1301 exhibited a higher nitrogen assimilation ability than 1304. These results indicated that the high-Mo-accumulation soybean cultivars accumulated high Mo which enhanced the high carbon and nitrogen utilization ability. Thus, breeding high Mo accumulation soybean cultivars could efficiently mprove Mo utilization of soybean.
The main purpose of the present study was to explore the methods of evaluating shade tolerance, analyze the shade tolerance of different soybean genotypes, screen suitable evaluation indicators of shade tolerance, and establish a mathematical evaluation model of shade tolerance. 44 soybean cultivars (lines) were treated under shading and natural light conditions in a field experiment. Corn-soybean intercropping system created the shading conditions in the field, and soybean single planting was used as control. 10 major morphological and yield characteristics of soybean cultivars (lines) were investigated during the mature period, based on the coefficient of the shade tolerance in each index, the shade tolerance of soybeans was evaluated with multivariate statistical method. The results showed that compared with the control, the changing trend of each characteristics and amplitude were different, each index existed in varying degrees of correlation and some correlation reached significant or highly significant levels. 4 independent comprehensive components were obtained from 10 single index by principal component analysis, which reflected 79.77% information of all traits information. The method of membership function was adopted to calculate comprehensive shade tolerance value (D) and make cluster analysis, and 44 soybean cultivars (lines) were divided into 3 shade tolerance types, Class I was the high shade tolerance type, Class II was the medium shade tolerance type and Class III was the low shade tolerance type. A mathematical evaluation model for shade tolerance of soybean was established by stepwise regression analysis. Based on the model, 8 index including plant height, main stem node number, effective branch, pods per plant, seeds per plant, yield per plant, seeds per pod and lodging could be used for identifing intercropping soybean varieties to shade tolerance in Yunnan Province.
To clarify the effects of different nitrogen (N) application on carbon (C) and N accumulation in oilseed rape and the distribution on the aboveground and underground, a hydroponic test was conducted. The seedling was grown in distilled water and cultured with full strength nutrient solution after transplanted. A total of 6 N levels were set for the test, and they were 0.01, 0.05, 0.1, 0.5, 1.0 and 6.0 mmol/L. Dynamics of dry matter, C and N aboveground and underground of oilseed rape within 35 days was investigated every 7 days. The results showed that with the increase of N application, the leaf area per plant, dry matter aboveground, N concentration and accumulation increased significantly. Dry matter, C and N accumulation underground increased as N application added and then decreased. The C concentration of both shoot and root were not affected. The substance accumulation underground of 0.1, 0.5, and 1.0 mmol/L treatment reached the higher level among the treatments on the 7th, 14th, and 21th days after transplanting, respectively. Substance accumulation underground increased as N application increased after 28d after transplanting. The R/S of dry matter decreased significantly as N supply increased. C accumulation per unit area of leaf and N accumulation per gram root improved with increasing N concentration as the N supply was deficient. Insufficient N supply increased the distribution of C and N to the root and reduced the rate of C and N accumulation in the plants, exerting greater influence on the aboveground.
Taking Gongqiao Village, Wen'an Town, Zhijiang City as an example, this paper studied the prevalence of rapeseed clubroot in Jianghan Plain during the period of 2008～2017 with the method of census and random sampling, compared the influence of soil conditions, cultivation measures and other factors on its outbreak. At the same time, randomized block design method was used to carry out field trials such as seedling-free transplanting at different sowing times, seedbed disinfection and rhizosphere fertilization. The results showed that the rapeseed clubroot in Jianghan Plain spreaded rapidly, and it was contiguous in 3～5 years. The main reason for the long-distance spread of this disease was mechanical operation. Soil acidification was the basis of its epidemic. Field trials showed that transplanting non-diseased seedlings to diseased fields evidently avoided disease and rapeseed yield loss was reduced. If sowing in mid-late September and transplanting one month later, the yield of rapeseed in rehabilitated fields could reach up to 2,500 kg / ha. Rhizosphere application of cyanamide calcium and cyazofamid could significantly reduce the disease index of clubroot, prevention effects were 50% and 90%, if both applied at the same time the effect was 100%. The control effect on the rapeseed clubroot was 100%, 96%, 76% and 62% respectively by adopting the cyanamide calcium stew shed, high temperature, fluazinam and cyazofamid to disinfect soil. The paddy soil in the Jianghan Plain is extremely sensitive to clubroot disease. The mechanized production, prevention and control of clubroot disease should be based on prevention. In order to reduce the cost of prevention and improve the control effect, it was recommended that the alkaline calcium fertilizer such as calcium cyanamide to be pelletized and applied as a seed and base fertilizer to the rhizosphere. In addition, seed coating with cyazofamid could be used for disease-free and mild disease fields, and cultivated disease-free seedlings could be transplanted after seedbed disinfected by fluazinam or Cyazofamid for seriously infected.
Aflatoxin contamination has been a key factor affecting food safety of peanut products and a serious constraint to peanut industry. The resistance to infection of Aspergillus flavus in shell is the preliminary physical protection mechanism for reducing risk of toxin contamination in peanut. However, very limited research has been done on identification method for shell resistance to A. flavus infection. In this research, peanut pods were inoculated with A. flavus strain AF2202 with 5 concentrations of inoculum solutions and then incubated for 3-9 days in darkness. Through comparing various combinations of inoculation and incubation period, the optimal combination for identifying shell resistance was 2 × 106 spores per milliliter and 7 days. A total of 276 diversified lines consisting of peanut core collections were tested using the newly-developed method, and the results further confirmed that the method was effective and practicable. Significant difference in shell resistance was found among the involved germplasm lines and 2 elite lines with shell resistance were identified.
Elsinochrome (ESC) produced by Elsinoë arachidis is a photosensitizing perylenequinone toxins, which performed crucial functions in the process of pathogen infection. In order to investigated a mechanism by which Elsinochrome contributes to the pathogenic success of this fungus, the content of reactive oxygen species, the activity of reactive oxygen scavenging enzymes and the degree of lipid membrane peroxidation in the host were systematically studied. The results showed that, after toxin inoculation, the content of superoxide anions (O2-) and hydrogen peroxide (H2O2) in the leaves peaked at 8h and reached 1482.99U·L-1 and 25.25μmol·g-1, respectively. It was 10 and 40 times as those of the clear water control. The activity peaks of SOD, CAT and POD in the active oxygen scavenging system appeared at 48 hours after inoculation, which were 78.00 U·mg -1, 16.20 U·mg -1 and 63.73 U·mg -1, respectively, and then decreased to the control level. Moreover, MDA content peaked after 72h, the peak value was 5.44 μmol·g-1, and the membrane permeability increased with the inoculation time, up to 80% at 96 h. The results suggested that the toxin induced necrotic lesions on peanut leaves, promoted the level of lipid peroxidation and killed cells by producing ROS. Thus, the toxin produced by Elsinoë arachidis was directly toxic in peanut.
To evaluate the efficiency of 20% picloram ? clopyralid ? clethodim OD, a novel pyridine and cyclohexenone herbicide, and to provide guidance for rational use in rapeseed field, its weed control effect, rapeseed yield, light intensity, the content of N-P-K and water were analyzed after weed control by picloram ? clopyralid ? clethodim. The experiment results indicated that the effect of weed control was remarkable by 20% picloram ? clopyralid ? clethodim OD. Beckmannia syzigachne,Vicia sativa, Alopecurus aequalis and Malachium aquaticum were all effectively controlled with reduction of total grass fresh weight ranged from 88.7 to 98.0%, which greatly improved the light intensity, water and fertilizer effectivity for rapeseed in field, and contributed to increase of rapeseed yield of 18.2~27.9% , income increase of 1086.8～1653.8 Yuan/hm2 compared to untreated control. It concluded that 20% picloram ? clopyralid ? clethodim OD was a promising herbicide in rape field, and the recommended dose was 225 ~ 300 g/hm2.
With the advancement of mechanization of rapeseed production in China, chlorophyll content of rapeseed increases significantly due to the inconsistent maturity of silique, which directly affects the quality of rapeseed oil and increases the processing cost. Therefore, establishment of rapid and non-destructive detection techniques for chlorophyll in rapeseed is important to quality control of rapeseed oil. In this study, the chlorophyll contents of 450 representative rapeseeds were quantitatively analyzed by UV-vis spectrophotometry. Subsequently, these rapeseeds were analyzed by near infrared spectroscopy (NIR). After the pretreatment of the first derivative and standard normal variate (SNV), and wavelength selection by competitive adaptive reweighted sampling (CARS), partial least squares (PLS) regression method was employed to construct the prediction model for chlorophyll content in rapeseed. The results of cross validation indicated that the coefficient of determination (Q2) of validation set was 0.9446, while the mean square error of cross validation (RMSECV) was 1.36 mg/kg. The results indicated that this method could accurately determine chlorophyll content in rapeseed, which provided an important technological support to quality control of rapeseed oil.
order to optimize the preparation process conditions of phosphorelated peanut protein isolate - polypeptide films, experiment was carried out with the response surface Box-Benhnken experiment, on the basis of single factor experiments. The results showed that the optimum conditions obtained were protein concentration, pH value, glycerol percentage content of protein, xanthan gum percentage content of protein, time, temperature, ultrasonic power, ultrasonic frequency, polypeptide concentration of 8%, 8.2, 13.4%, 1%, 60min, 69℃, 270w, 28kHz, 61mg/mL, respectively. Under the optimum conditions, the theoretical predictive values of film thickness, water absorption and light transmittance were 86μm, 41.9% and 53.6%, respectively. The results of verification experiment showed that film thickness, water absorption rate and light transmittance rate could reach 88±2μm, 43.1±1.2% and 52.4±1.5%, respectively. The differences between experimental and theoretical values were 2.33%, 2.86% and 2.24%, respectively. This suggested the response surface quadratic model fitted well. The functional properties were better than those of phosphorelated modified peanut protein isolate films, and these functional properties included tensile strength of 9.62 MPa, elongation of 101.68 %, solubility of 47.69 %, water vapor permeability of 6.95 g•(m2·h)-1 and antioxidant activities including DPPH free radical scavenging activity of IC50 7.70 mg·mL-1, hydroxy free radical scavenging activity of IC50 5.98 mg·mL-1, superoxide anion free radical scavenging activity of IC50 4.20 mg·mL-1, iron ion chelating activity of IC50 3.79 mg·mL-1, copper ion chelating activity of IC50 13.61 mg·mL-1, lipid peroxidation inhibition activity of IC50 8.62 mg·mL-1, iron reducing power of IC50 13.93 mg·mL-1, molybdenum reducing power of IC50 5.49 mg·mL-1 of phosphorelated peanut protein isolate - polypeptide films. The results of this study provided a new way for the application of phosphorelated peanut protein isolate.
As a highly efficient processing method, microwave technology has gradually received attention in the application of rapeseed processing. Polyphenol content of rapeseed oil processed by microwave technology significantly increased, up to 120 times. The contents of sterols and vitamin E in rapeseed oil plants also were improved. After microwave pretreatment, the degradation of glucosinolate was accelerated. Compared with traditional roast, microwave rapeseed oil has a richer flavor. This article will be focuse on the application of microwave technology on rapeseed processing.
