Current issue

• 2019 Vol.35 No.7 Published:04 March 2019

  The effects of combined application of straw with lime, urea and compost on Cd accumulation of rice 2019, 35 (7):  1-6.  DOI: 10.11924/j.issn.1000-6850.casb17110004 Abstract + ( 844 )   PDF ( 944KB )   ( 284 ) To make use of straw resources safely, we select the Cd-contaminated paddy in Mianzhu County of Sichuan Province as the research object to carry out plot experiment, and study the effects of returning straw added with lime, urea and straw-decomposing inoculant on soil properties, Cd accumulation and yields of two rice varieties (low-enriched rice variety‘Chuanyou 6203’and high-enriched rice variety‘Yixiang 2115’). The results showed that compared with the control (CK), returning straw added with lime significantly increased soil pH value (P<0.05), slightly increased the concentration of soil dissolved organic carbon (DOC), and decreased the concentration of soil available Cd; returning straw added with urea slightly increased soil pH value, DOC, and available Cd concentrations, while returning straw added with straw-decomposing inoculant decreased soil pH value, significantly increased soil DOC and available Cd concentrations (P<0.05). Compared with CK, returning straw added with lime decreased the rice Cd concentration by 13.1%-14.4%, while straw returning combined with urea and straw- decomposing inoculant application increased the rice Cd concentration by 3.4%-13.1% and 21.2%-35.6%, respectively. Straw returning with lime, urea and straw- decomposing inoculant increased the yields of rice by 5.7%- 7.1% , 9.4%- 9.7% and 10.6%- 11.4% , respectively. Considering Cd absorption and yields of rice, we suggest that straw returning with lime is an ideal model for the safe utilization of straw in Chengdu Plain.

  Fertilizer Amount Affecting Leaf SPAD Value of 2 Super Rice Varieties 2019, 35 (7):  7-14.  DOI: 10.11924/j.issn.1000-6850.casb17110015 Abstract + ( 872 )   PDF ( 1043KB )   ( 260 ) The objectives are to discuss the change regulation of leaf SPAD value of super rice‘Songjing 9’ and‘Songjing 15’, and determine the relationship between leaf SPAD value and yield traits. Using the two super rice varieties as materials, by a field plot comparison test, the changes of SPAD value of the 4 top leaves at jointing stage, heading stage, filling stage and mature stage were studied under different fertility conditions. The results showed that, with the increase of fertilizer amount, the leaf SPAD value of the 2 super rice varieties showed a gradual increasing trend, and the higher the fertilizer amount, the smaller the increase was. Throughout the whole investigation period, SPAD value of the‘Songjing 15’was significantly higher than that of‘Songjing 9’. The leaf SPAD values of the 2 super rice varieties were positively correlated with the number of spikes per hole, grain number per panicle and yield per hectare, negatively correlated with seed setting rate and 1000-grain weight. The correlation between SPAD value and grain number per panicle and seed setting rate was closer, and the correlation reached a significant or extremely significant level.

  Planting Density Affects Population Traits and Yield of Wheat in Weibei Arid Region 2019, 35 (7):  15-19.  DOI: 10.11924/j.issn.1000-6850.casb17110132 Abstract + ( 745 )   PDF ( 921KB )   ( 241 ) To screen suitable planting density of major wheat cultivars in Weibei arid region, experiments were carried out using‘Tongmai-6’and‘Changhang-1’as experiment materials, to determine the effect of varied planting density on the growth stage, population traits, yield and yield components. The results indicated that there was no significant effect of planting density on wheat growth stage; with the increase of planting density, the spike rate showed an upward trend at first and then decreased, and reached the highest at 330×104 plant/hm2; the effect of planting density on spike number was obvious, but that on 1000-grain weight was not significant.‘Tongmai-6’showed the maximum yield (4389.50 kg/hm2) at the planting density of 330× 104 plant/hm2, while the yield of‘Changhang- 1’reached its maximum (4531.20 kg/hm2) at the planting density of 390 × 104 plant/hm2. However, no significant difference was observed when the planting density ranged from 270×104 to 390×104 plant/hm2(P>0.05). Taking all into consideration, our research results suggest that the planting density of 330×104 plant/hm2 is an optimal one for the two wheat cultivars in Weibei arid region.

  Evolution Characteristics of Major Agronomic Characters of Main Planting Wheat Varieties in Shandong Province in 60 Years 2019, 35 (7):  20-27.  DOI: 10.11924/j.issn.1000-6850.casb18100044 Abstract + ( 966 )   PDF ( 928KB )   ( 650 ) Understanding the evolution characteristics of major agronomic characters of main planting wheat varieties can provide a basis for new variety breeding and cultivation innovation. 50 main planting wheat varieties of different years in Shandong Province were used as materials, the evolution characteristics of agronomic characters and economic coefficient, and their correlation were analyzed. The results showed that, the plant height presented an extremely significant decreasing trend with the time. Every cultivar alternation decreased the plant height by 6.29 cm on average. The 1000-seed weight showed an extremely significant increasing trend, every cultivar alternation increased 1000-seed weight by 1.26 g on average. The economic yield and biological yield per stem decreased first and then increased, and they showed an extremely significant positive correlation. The economic coefficient increased significantly, and every cultivar alternation increased the economic coefficient by 24.33% on average. There was no significant change trend in spike length, kernel number per spike, total spikelet number, and the number of fertile spikelet in different years. The trend of economic yield and biological yield per stem was different from the trend of grain yield, indicating that the coordination between population yield and individual yield was an important direction to improve grain yield of wheat.

  Effects of Waterlogging Stress on Photosynthetic Parameters of Waterlogging-Tolerant and Susceptible Rapeseed Lines 2019, 35 (7):  28-35.  DOI: 10.11924/j.issn.1000-6850.casb18090105 Abstract + ( 717 )   PDF ( 985KB )   ( 353 ) To study the effects of waterlogging stress on photosynthetic parameters of waterlogging-tolerant (WT) and susceptible rapeseed lines, 9 WT lines and 7 susceptible lines were selected and fully submerged on five leaves stage. Photosynthetic parameters were detected before waterlogging and 4 days (D), 8 D, 12 D and 16 D after waterlogging. According to the results, the photosynthetic rate (Pn) of the rapeseed lines increased after 4 days of waterlogging, but declined hereafter. The drop rate of WT lines (16.0%) was smaller than the susceptible lines (32.4%) after 16 days of waterlogging. The transpiration rate (Tr) of the WT lines kept on rising after the waterlogging treatment, but the susceptible lines raised to the peak (4.35±0.87) after 12 days of waterlogging and then declined. The stomatal conductance (GS) of the WT lines increased along with days of treatment, but the susceptible lines raised to the peak (0.61±0.11) after 12 days of waterlogging and then declined. The intercellular CO2 concentration (Ci) of the rapeseed lines increased to the peak after 12 days of waterlogging and then declined. The water use efficiency (WUE) of the rapeseed lines declined significantly after waterlogging, but the WUE of the WT lines declined slower than the susceptible lines. The results showed that the photosynthetic adjusting capacity of WT lines could decrease the drop rate of Pn and delay the damage of waterlogging on the plants at a longer time than susceptible lines.

  Germplasm Resources of Tabebuia and Handroanthus in South China: Morphology and Molecular Identification 2019, 35 (7):  36-41.  DOI: 10.11924/j.issn.1000-6850.casb18100035 Abstract + ( 850 )   PDF ( 1632KB )   ( 419 ) Tabebuia and Handroanthus (Bignoniaceae) are native to central and south America, and widely cultivated in south China because of the high ornamental value, but the provenance of these plants is still unclear. We carried out the morphology and molecular identification of these plants cultivated in south China. The results indicated that: 7 taxa belonged to 4 species from 2 genera (Tabebuia and Handroanthus), including T. rosea, T. aurea, H. impetiginosa and 2 subspecies of H. chrysanthus (H. chrysanthus subsp. chrysanthus and H. chrysanthus subsp. meridionalis). 3 taxa with main difference in petal color could not be distinguished at the molecular level, supporting them as one species. Correct classification of these species will contribute to the hybrid breeding, scientific management and landscape application.

  Effects of Different Treatments on Seed Germination and Seedling Growth of Red Beech 2019, 35 (7):  42-47.  DOI: 10.11924/j.issn.1000-6850.casb17100035 Abstract + ( 689 )   PDF ( 1021KB )   ( 246 ) To ascertain the germination characteristics of red beech seed and the growth law at seedling stage under different conditions, and to improve the germination rate of seeds, six treatments were set up in this study, including GA3 soaking, concentrated H2SO4 soaking, water bath with different temperatures, stratification-field temperature-changing stratification, different substrate treatments and the control (CK). The results showed that: (1) the red beech seeds from Changzhou dipped in water had the highest germination rate of 100%, the highest germination rate of dry seeds from Changzhou sown in vermiculite was 93.33%; (2) dipped in water for four days and had water bath of 60℃ for 20 min, the ground diameter of the red beech reached up to 14.55 mm, and the minimum ground diameter was 6.08 mm when the concentration of GA3 was 50 mg/L; (3) with stratification treatment, the highest nursery stock of red beech collected from Shuyang Jiangsu was 116.80 cm, the lowest nursery stock was 70.50 cm when the seeds dipped in water for four days and had a water bath of 60℃ for 30 min. Taken together, different treatments had significantly different effects on the germination rate, seeding height, ground diameter, germination index and vigor index. Therefore, different treatments should be handled according to different needs.

  Growth Characteristics and Resistance of Introduced Poplar Varieties in Jianghan Plain 2019, 35 (7):  48-53.  DOI: 10.11924/j.issn.1000-6850.casb17110076 Abstract + ( 627 )   PDF ( 1052KB )   ( 435 ) To select suitable poplar varieties for cultivation in large scale in Jianghan plain, using nineteen introduced poplar clones such as‘Danhong’and the main planted poplar variety‘Zhongqian 3’of Jianghan plain as the materials, this article analyzed the growth, wood properties and resistance of the twenty poplar clones at six-year-old and twelve-year-old. The results showed that there were significantly differences in the DHB, height and volume among the six-year-old and twelve-year-old twenty poplar clones. Among all the poplar clones, five clones,‘Danhong’,‘Juba261’,‘DD102-4’,‘Nanlin 895’and‘Juba2025’, performed prominently, the volumes of which were higher than the that of‘Zhongqian 3’by 107.7%, 50.18%, 39.8%, 50.9%, and 42.1%, respectively, at twelve-year-old. The five poplar clones had differences or significant differences in basic density and fiber length. The‘Danhong’and‘Lushan’showed strong disease and insect resistance. According to the rhythm of volume rowth,‘Danhong’is suitable for cultivating little-middle DBH or big-diameter timber,‘Juba261’is suitable for cultivating big-diameter timber, and the other three clones are suitable for cultivating small and middle timber.

  Exogenous Hormone Treatments Affect the Rooting Rate of Amesiodendron chinense 2019, 35 (7):  54-57.  DOI: 10.11924/j.issn.1000-6850.casb18040124 Abstract + ( 771 )   PDF ( 986KB )   ( 408 ) The paper aims to study the effects of different hormones on the rooting of cutting of Amesiodendron chinense, and to increase the rooting rate by finding out suitable rooting methods. We explored the effects of 3 factors including hormone type, hormone concentration, and soaking time respectively on the rooting rate and healing rate by using the mature mother plant of A. chinense as the testing material. The results showed that: all the 3 factors (hormone type, hormone concentration, and soaking time) had significant impacts (P<0.05) on the cutting rooting rate and healing rate of A. chinense; the most significant factor was soaking time, not hormone type; hormone type and hormone concentration had impact on the healing rate of A. chinense and the impact of hormone type was greater than that of concentration; the rooting rate could reach to 62.22% when A. chinense were treated with IBA solution of 500 mg/L for 10 min.

  Bletilla formosana: Photosynthetic Characteristics and the Correlation with Factors 2019, 35 (7):  58-63.  DOI: 10.11924/j.issn.1000-6850.casb18040066 Abstract + ( 607 )   PDF ( 1035KB )   ( 263 ) The paper aims to provide references for the introduction and protection of wild Bletilla formosana, as well as its high-yield cultivation techniques. We measured photosynthetic characteristics of B. formosana from 5 different origins by Li- 6400XT Portable Photosynthesis System. The results showed that: (1) B. formosana transplanted from Pingbian and Taiwan were typical shade- tolerant plants, with their light saturation points of (325.7 ± 28.1622) and (259.6 ± 20.2951) μmol/(m2 · s), respectively, and their light compensation points of (18.62 ± 4.1350) and (3.70 ± 1.3116) μmol/(m2 · s), respectively; (2) B. formosana transplanted from Gejiu, Sichuan and Mengzi had strong adaptability to the environment, with high light compensation points and low light saturation points; from the perspective of production, they had a large advantage in introduction, cultivation and protection; (3) the correlation analysis showed that: intercellular CO2 concentration (Ci), leaf temperature (TL) and relative humidity (RH) were closely related with net photosynthetic rate (Pn). The research clarifies the life style of B. formosana from 5 different origins and the related factors, which could provide a foundation for the introduction and protection of B. formosana

  Cabbage Yield, Quality and Soil Nutrient Balance Under Reduced Fertilizer Rate 2019, 35 (7):  64-68.  DOI: 10.11924/j.issn.1000-6850.casb18090041 Abstract + ( 805 )   PDF ( 874KB )   ( 257 ) This study aims to investigate the effects of fertilizer reduction with applying amino acid and Bacillus mucilaginosus on yield, quality, partial productivity of nitrogen fertilizer of cabbage and soil nutrient balance. The results showed that the cabbage yield of fluid fertilizer(YTF) increased by 15.9% compared with that of solid fertilizer (GTF), while the yield of amino acid fluid fertilizer (AYTF) and amino acid fluid fertilizer containing B. mucilaginosus (AYTFM) increased by 6.6% and 10.3% respectively compared with that of YTF. However, under nitrogen reduction of 20%, the yield of AYTFJ and AYTFMJ increased by 3.9% and 7.1% compared with that of YTF. The nitrate content was the highest in GTF treatment and significantly decreased in fluid fertilizer treatments, and the AYTFJ treatment had the lowest value under 20% nitrogen reduction. Amino acids and B. mucilaginosus could increase soluble sugar and vitamin C content in cabbage, and AYTFM treatment had the highest soluble sugar content and significantly increased by 13.9% compare with that of YTF. Vitamin C content was the highest in AYTFMJ treatment and significantly increased by 7.6% compared with that of YTF. Amino acid and B. mucilaginosus could significantly increase the partial productivity of nitrogen fertilizer, especially in nitrogen fertilizer reduction treatments. Application of amino acids and B. mucilaginosus could increase nutrient accumulation and reduce soil nutrient surplus. Amino acid and B. mucilaginosus have obvious effect on saving fertilizer and enhancing efficiency.

  Effects of Different Planting Densities on Yield and Its Component Factors of Pyrethrum cinerariifolium 2019, 35 (7):  69-76.  DOI: 10.11924/j.issn.1000-6850.casb17110064 Abstract + ( 695 )   PDF ( 1056KB )   ( 215 ) Single factor randomized block design is used to study the effects of different planting densities on yield, output value, and yield component factors, thus to obtain the most optimum one under seedling transplanting condition. The results showed that the effects of planting densities on dried flower yield, unit output value, pyrethrin production reached extremely significant level in parabolic curve relationship. And the effective pedicel number was the most important factor affecting both dry flower and pyrethroid yield. The results also showed that the plant density was negatively correlated with the effective pedicel number, the flower number and the percentage of useless pedicel and bud per plant. However, there was a Logistic function relation between the planting density and the number of effective pedicels and flowers per unit area. In addition, the growth period of Pyrethrum cinerariifolium was shortened with the increase of planting density, while the morbidity of root rot was positively correlated with the increase of planting density. In considering the yield, output value, period of growth, morbidity and plant height, the best planting density is 60000-90000 plants/hm2 under floating-seedling transplanting condition in P. cinerariifolium planting area of Yunnan.

  An Entomogenous Fungus: Isolation, Evolutionary Relationship Analysis and Pathogenicity Determination 2019, 35 (7):  77-82.  DOI: 10.11924/j.issn.1000-6850.casb18100026 Abstract + ( 671 )   PDF ( 1540KB )   ( 460 ) The study aims to screen entomopathogenic fungus with pathogenicity against the Lymantria dispar. The infected chrysalises of L. dispar were collected from Harbin Youth Park, the strain was isolated and purified, and identified with morphological characteristics and rDNA ITS sequence alignment analysis. At the same time, the pathogenicity on the L. dispar larvae was studied by spray method. An entomopathogenic fungus was isolated from collected chrysalis of the L. dispar, and named HEB-2016. The colony characteristics were different in different culture media, and the microstructure results were consistent with the characteristics of Aspergillus. The result of rDNA ITS sequencing showed that the obtained fragment length was 595 bp. The comparison result showed that the sequence similarity with Aspergillus ochraceus and A. westerdijkiae was 98%- 100%, and it was identified as A. westerdijkiae by the phylogenetic tree. This strain had strong pathogenicity against the L. dispar larvae. After 7 days of treatment with spores suspension at the concentration of 108 cells/mL, the corrected mortality rate was 80.69%. The sporulation structure of the strain was visible to naked eyes after 10 days. HEB-2016 has pathogenic against L. dispar. The strain can be the candidate strain resource for controlling L. dispar and developing biological pesticides.

  Carbon Dynamics Simulated on BIOME-BGC Model: Wudaoliang Grassland Ecosystem in the Qinghai-Tibet Plateau 2019, 35 (7):  83-89.  DOI: 10.11924/j.issn.1000-6850.casb18100001 Abstract + ( 1097 )   PDF ( 1546KB )   ( 308 ) The Qinghai-Tibet Plateau is a sensitive region to climate change and grassland is the most widely distributed vegetation there. It is important to study the dynamics and trends of carbon in grassland ecosystem for understanding the impact of carbon on climate change. In this study, plant carbon, litter carbon, soil carbon and total carbon in Wudaoliang grassland ecosystem in the Qinghai-Tibet Plateau from 1961 to 2015 were simulated using BIOME-BGC model with localized parameters. The results showed that: (1) soil organic carbon was the main component of total carbon, accounted for 95% of total carbon sequestration, litter carbon and plant carbon was 4% and 1%, respectively; (2) the total carbon decreased slightly from 1961 to 2015 with a rate of -0.018%/a; plant carbon increased significantly with a growth rate of 0.187%/a; litter carbon decreased in these years, but there was a marked hysteresis to climate change; soil organic carbon (SOC) decreased ( -0.019%/a) with the increase of soil respiration rate due to warming, but its variation was small because of its strong resistance to external disturbance. The results indicate that warming leads to the increase of vegetation carbon, however, enhanced soil respiration causes a reduction in soil organic carbon and offsets the increase in vegetation carbon. As a result, warming leads to the decrease of total carbon.

  Park Green Space in Main Urban Area of Lanzhou: Accessibility Analysis Based on G2SFCA 2019, 35 (7):  90-96.  DOI: 10.11924/j.issn.1000-6850.casb18050084 Abstract + ( 652 )   PDF ( 1532KB )   ( 287 ) To explore the rationality of the distribution pattern of park green space in the main urban area of Lanzhou, based on ArcGIS, we analyzed the accessibility of park green space in main urban areas of Lanzhou from the supply point and demand point by using Gaussian two-step floating catchment area method. The results showed that: the number of park green space in main urban area of Lanzhou was insufficient and the area was very small, the spatial distribution was quite uneven, most of the parks focused on both sides of the Yellow River in Chengguan, and green parks were deficient in Qilihe District, Shajingyi Street in Anning District, Liuquan and Xiliugou in Xigu District, Donggang Street ind Chengguan District. Overall, in 30 minutes, the service area of green space could cover most streets, but the accessibility was poor in 15 minutes. By analyzing the relationship between population density and accessibility, it is found that most of the residents live in the streets with low accessibility, and the total service quantity of the green space is inconsistent with the population density.

  The Relationship Between Cultivated Land Change and Economic Development in Jiangsu: An Empirical Study 2019, 35 (7):  97-104.  DOI: 10.11924/j.issn.1000-6850.casb17110055 Abstract + ( 552 )   PDF ( 1264KB )   ( 331 ) This paper uses the Eviews 8.0 software, Chow test, ADF test, cointegration analysis, AIC criterion, Granger causality test and other econometric methods to analyze the relationship between cultivated land area change and economic growth in Jiangsu from 1978 to 2009, and summarizes the characteristics of the relationship. The results showed that since 1978, the cultivated land area of Jiangsu and the economic development had experienced two stages: the first stage (1978 to 1991) was causality, in which the economic growth was mainly at the expense of the cultivated land; the second stage (1992 to 2009) was one- way causality, in this stage, the decrease of cultivated land resources provided land security for economic development, but the economic growth was not the reason of cultivated land resources change. For the longterm of 1978 to 2009, the economic growth and the change of cultivated land was a one- way causal relationship, namely, the quantity change of cultivated land had a positive impact on the economic development, but the economic development was not the reason for the decrease of cultivated land area. Finally, the paper puts forward suggestions on how to deal with the contradiction between cultivated land protection and economic development, which can provide certain references for future research on the related issues.

  Summer Precipitation in Huainan from 1957 to 2017: Variation Characteristics 2019, 35 (7):  105-109.  DOI: 10.11924/j.issn.1000-6850.casb18090093 Abstract + ( 755 )   PDF ( 1401KB )   ( 296 ) Based on the daily precipitation data of Huainan from 1957 to 2017, we adopted trend analysis, Morlet wavelet analysis, Mann-Kendall test and sliding t test to study the interdecadal variation, periodic characteristics and catastrophic characteristics of summer precipitation in Huainan. The results showed that: (1) the interdecadal variation of summer precipitation in Huainan had an increasing trend; (2) the linear increase of the proportion of rainstorm was significantly higher than that of the rainstorm days and rainstorm amounts, and the probability of future extreme rainstorm was increasing; (3) there was a quasi- two- year oscillation of the main period of summer precipitation in Huainan, and there were 9, 18 and 32 years oscillation period in addition; (4) the summer precipitation in Huainan in 1967 and 2008 showed a partial mutation which was not obvious. In the future, the precipitation and the extreme intensity of heavy precipitation along the Huaihe River will increase, which will bring challenges to flood control and agricultural production.

  Steep Descent of Temperature in the Northeastern Qinghai-Tibet Plateau: Threshold Values and Climatic Characteristics 2019, 35 (7):  110-116.  DOI: 10.11924/j.issn.1000-6850.casb18100008 Abstract + ( 716 )   PDF ( 1435KB )   ( 395 ) Aiming at the meteorological forecast and corresponding service for steep descent of temperature in the northeastern Qinghai-Tibet Plateau, based on the daily minimum temperature data of 68 meteorological stations from 1961 to 2017, we discussed the threshold values in the process of steep descent of temperature and its climate characteristics by employing the means of trend analysis and correlation analysis, and built a forecast diagnostic model with NECP/NCAR (2.5°×2.5°) SST field and height field. The results showed that: (1) it was more in line with the actual situation to use the improved steep descent of temperature indexes to summarize the characteristics of the occurrence of cold wave; (2) due to the influence of landform and mountain barriers, there were obvious differences in the regional distribution of the times of steep descent of temperature in the northeastern Qinghai-Tibet Plateau, and the times of steep descent of temperature in the mountainous areas and eastern areas at higher altitudes were significantly more than those in the basins, the times of 24- hour cold wave in the southern mountain areas were more than those of 48-hour and 72-hour; (3) in recent 57 years, the frequency of regional cold waves showed a general downward trend, and the deceleration rate in the south and the north was -0.5 times/10 a and -0.4 times/10 a, respectively; which passed the significance test, the deceleration rate in the northwestern basin area was -0.1 times/10 a, which failed to pass the significance test; (4) the moving path of high cold air was a key signal for the prediction of steep descent of temperature. The research results could provide a basis for the decision-making concerning agricultural and animal husbandry resources and tourism resources.

  Biological Characteristics of Fusarium oxysporum Infecting Pachira macrocarpa 2019, 35 (7):  117-122.  DOI: 10.11924/j.issn.1000-6850.casb17110075 Abstract + ( 580 )   PDF ( 1431KB )   ( 360 ) The thesis aims to study the biological characteristics of Fusarium oxysporum, which is isolated and purified from Pachira macrocarpa. The results showed that the growth rate of F. oxysporum varied under different temperature (27℃>24℃>30℃>33℃>36℃>40℃), and the respective growth rate was: 97.93%> 95.48%> 12.75%> 4.93%> 2.23%> 1.48%, and the optimum growth temperature for F. oxysporum was 27℃. Growth velocity mensuration containing poisonous medium culture was used to screen various fungicides that could inhibit the growth of F. oxysporum. The results showed that: the fludioxonil reached the highest inhibitory rate (80.87%) atthe effective concentration of 62.5mg/L under1000timesdilution,andEC50 valuewas64.59mg/L. The chemical toxicity regression was Y=4.351+0.359x calculated using the least square method. Azoxystrobin at the effective concentration of 250 mg/L under 1000 dilution, reached the highest inhibitory rate of 74.19%, and the EC50 value was 78.17 mg/L. The virulence regression equation was: Y=2.419+1.363x. Thiophonatemethyl inhibited the pathogen most effectively (85.80%) at the concentration of 700 mg/L under 1000 times dilution, the EC50 value was 202.61 mg/L and toxicity regression equation was Y=0.575+1.919x.

  Identification of Sugar Beet Varieties with High Resistance to Cercospora Leaf Spot and High Sugar Content in Field 2019, 35 (7):  123-127.  DOI: 10.11924/j.issn.1000-6850.casb17110014 Abstract + ( 686 )   PDF ( 1199KB )   ( 217 ) This study aims to select sugar beet varieties with high resistance to Cercospora leaf spot (CLS) and high sugar content, thus to improve the economic benefits. From 2015 to 2016, we conducted field experiments with natural incidence analysis, 15 varieties were used as treatments with randomized block arrangement and four repeats. CLS index and sugar content in commercial sugar beet varieties were investigated. Statistical analysis results showed that the resistance to CLS among different sugar beet varieties showed extremely significant difference, the resistance to CLS was not stable, and the difference among different years was relatively large. The sugar contents among different sugar beet varieties showed extremely significant difference. The sugar contents of the same variety in different years had difference. In conclusion, the sugar beet variety with high and stable CLS resistance and high sugar content is‘KWS1197’, the average disease index and sugar content of two years are 18.34 and 14.01%, respectively.

  Resistant Biotype Avena fatua L. in Spring Rape Field: Resistance Mechanisms to Haloxyfop-P-methyl 2019, 35 (7):  128-133.  DOI: 10.11924/j.issn.1000-6850.casb18030068 Abstract + ( 558 )   PDF ( 1290KB )   ( 208 ) We verified three enzyme mechanisms of resistant biotype Avena fatua L. against Haloxyfop-Pmethyl, in order to provide a basis for controlling and delaying weed resistance. We tested the difference of ACCase, CYP450 reductase and GSTs activities in Haloxyfop-R-methyl resistant and sensitiveA vena fatua L. biotypes by potting method in greenhouse. The results showed that: the ACCase activity of resistant biotype Avena fatua L. was lower than that of sensitive biotype when herbicides were not applied; with the increase of Haloxyfop-R-methyl concentration, the activity of 2 biotype ACCase decreased gradually, but the decrease of there sistant biotype wasless than that of the sensitivebiotype, the two ACC aseactivity IC50 valuewas78.369μmol/L and 43.469 μmol/L, respectively, and the active multiple was 1.8; there was no significant differences in the activity of CYP450 reductase and GSTs between the resistant biotype and sensitive biotype of Avena fatua L. under water treatment; the activity of the resistant bio-type CYP450 reductase and GSTs was higher than that of the sensitive biotype after the application; after 12 days of application, the content of the resistant biotype and the sensitive biotype CYP450 reductase was 113.1 pmol/L and 38.9 pmol/L, respectively, the activity multiple was 2.91, and the 2 biotypes’GSTs activity was 210.6 mIU/L and 319.1 mIU/L, respectively, and the active multiple was 1.52. The high level of target enzyme activity and the enhancement of metabolic enzyme activity are important mechanisms for the resistance of Avena fatua L. to Haloxyfop-P-methyl.

  Determination of betaine in red Sugarbeet by hydrophilic interaction liquid chromatography-tandem mass spectrometryZhou Qin<sup>1,2,3,4</sup>, Wu Yumei<sup>1,2,3,4</sup> 2019, 35 (7):  134-138.  DOI: 10.11924/j.issn.1000-6850.casb18100041 Abstract + ( 566 )   PDF ( 1293KB )   ( 262 ) The study aims to establish a quantitative analysis method for detecting betaine in red sugarbeet. By using the modified QuEChERS method combined with liquid chromatography-tandem mass spectrometry, the sample was extracted with methanol through accelerated solvent extraction(ASE), and purified by solid phase extraction, detected by hydrophilic interaction liquid chromatography- tandem mass spectrometry under multiple reaction monitoring mode and quantified by the external standard method. The results showed that linearity range was 0.05-5 μg/mL in the test. When the adding level was 4-16 mg/g, the recovery was 87.7%- 95.7%, and RSD was between 3.6% and 8.4%. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.01 and 0.04 mg/L, respectively. The method is easy, quick, highly sensitive, and suitable for determination of betaine in sugabeet.

  Research Progress of Nondestructive Diagnostic Technique of Chlorophyll in Plants 2019, 35 (7):  139-144.  DOI: 10.11924/j.issn.1000-6850.casb17110025 Abstract + ( 467 )   PDF ( 1123KB )   ( 301 ) Nitrogen is one of the essential nutrient elements for crop growing and development, 70%-80% of the nitrogen in plant leaves is found in chloroplast. So the chlorophyll content can reflect the nitrogen nutrition status in plants. The study introduced the traditional detection technology of chlorophyll in plants, pointed out the problems in the promotion and application, summarized the research progress on the nondestructive diagnostic technique of chlorophyll in plant at home and abroad, and analyzed the significance of nondestructive diagnostic technique of chlorophyll in diagnosing the nitrogen nutrition in plants and the fertilization recommendation. In conclusion, the chlorophyll analysis technology is more suitable for application, and the nondestructive diagnostic technique of chlorophyll based on optical diffuse reflectance theory is very promising.

  Three Bacteria Isolated from Trionyx sinensis: Identification and Pathogenicity 2019, 35 (7):  145-152.  DOI: 10.11924/j.issn.1000-6850.casb17100107 Abstract + ( 822 )   PDF ( 1486KB )   ( 250 ) Due to the outbreak of a deadly disease on Chinese turtle (Trionyx sinensis), this study aims to find out the pathogenic factor, and identify the biological status, the etiology and drug resistance characteristics of isolated bacteria. Three pathogenic bacteria assigned as C1, C2, C3 were isolated from the diseased Chinese turtle (Trionyx sinensis). The pathogenic effect of the isolated bacteria was determined through artificial regression on healthy Chinese turtle. Species of bacteria were classified through morphological observation, physiological and biochemical identification, 16S rRNA sequencing and phylogenetic analysis. Kirby-Bauer agar diffusion method was used for the drug sensitivity test. The three isolated bacteria strains were classified as Citrobacter freundii, Morganella morganii, and Klebsiella pneumoniae. Isolated bacteria could cause acute infectious disease on healthy Chinese turtle, and the mix of 3 species of bacteria could lead to almost 100% mortality. Drug- sensitivity tests showed that Citrobacter freundii were highly sensitive to Ceftazidime, Ceftriaxone and Levofloxacin, while extremely resistant to 17 kinds of drugs such as Vancomycin; Morganella morganii were very sensitive to Ceftriaxone, Ceftriaxone and highly resistant to 17 kinds of drugs such as Clindamycin; Klebsiella pneumoniae were hypersensitive to 13 kinds of drugs such as Enrofloxacin and extremely resistant to 6 kinds of drugs such as Penicillin. This study showed that Citrobacter freundii, Morganella morganii and Klebsiella pneumoniae were the pathogenic bacteria which caused the deadly disease outbreak on the Chinese turtle. The pathogenicity of the 3 mixed isolate bacteria was stronger than any single bacteria strain. Citrobacter freundii and Morganella morganii showed a high degree of multi-drug resistance, while resistant tendency of Klebsiella pneumoniae is different from the others, which was a weak resistant strain.

  Oxytocin Affects the Reproduction of Pseudobagrus fulvidraco♀×P. vachelli♂ 2019, 35 (7):  153-157.  DOI: 10.11924/j.issn.1000-6850.casb18100112 Abstract + ( 704 )   PDF ( 1188KB )   ( 227 ) To study the effects of different fish oxytocin and their combinations on the reproductive performance of hybrid yellow-headed catfish, three kinds of fish oxytocin were selected, each hormone had 3 levels, and a total of 9 combinations were injected into the breeding parents. Different-dosage combinations of the three kinds of fish oxytocin had a great influence on the induced spawning rate, fertilization rate and hatching rate. The induced spawning rate, fertilization rate and hatching rate of group 9 was 90.0%, 84.7%, 88.9%; and the induced spawning rate, fertilization rate and hatching rate of group 8 was 92.5%, 83.2%, 85.1%. Different doses of the same oxytocin had a certain effect on the effective time of the parent fish. The effective time of group 9 was the shortest (23 h), while that of group 2 was the longest (30 h). In group 9, the combination of luteinizing hormone-releasing hormone, domperidone and human chorionic gonadotropin had the best combination effect.

  Different Concentrations of Cyanotis arachnoidea Extracts in Feed Affect Macrobrachium rosenbergii Growth, Protein Metabolism and Nutritional Components in Muscle 2019, 35 (7):  158-164.  DOI: 10.11924/j.issn.1000-6850.casb18040017 Abstract + ( 813 )   PDF ( 1304KB )   ( 240 ) The paper aims to study the effects of adding different concentrations of Cyanotis arachnoidea (CA) extracts in feed on the growth, protein metabolism and nutritional components in muscle of Macrobrachium rosenbergii. Adding 7.5, 67.5 mg/kg CA to the basic diet which was the control group, we made 3 kinds of feed with equal energy and nitrogen, and did the feeding test for 8 weeks. The results showed that: adding 7.5 mg/kg CA in basic diet had no significant effect on the growth performance, feed utilization, enteric and hepatic digestive enzyme (protease, lipase and amylase) activities, hepatic aminotransferase (alanine aminotransferase and aspartate aminotransferase) activities, muscular nutrient composition (moisture, crude protein, crude lipid and ash) and muscular fatty acids contents; however, adding 67.5 mg/kg CA significantly improved the growth performance, feed utilization, enteric protease activity, hepatic AST activity and muscular delicious amino acids (aspartic acid, glutamic acid and glycine) and crude protein contents of Macrobrachium rosenbergii.