Current issue

• 2019 Vol.35 No.5 Published:13 February 2019

  Pre-harvest Sprouting Resistance of Sichuan Wheat Varieties (Lines): An Evaluation 2019, 35 (5):  1-6.  DOI: 10.11924/j.issn.1000-6850.casb18080123 Abstract + ( 885 )   PDF ( 1643KB )   ( 380 ) The pre-harvest sprouting controlled by growth environment, seed color and genetic gene, could seriously influence the yield and quality of wheat. Due to the high temperature and high humidity condition during the wheat harvest season, Sichuan is the frequent and severe occurrence area of pre-harvest sprouting. According to the pre-harvest sprouting resistance of the materials, the purposeful selection and preparation of hybrid combinations to breed resistant varieties is an important strategy to control the pre-harvest sprouting. And it is important to systematically identify the pre-harvest sprouting resistance of each excellent varieties and lines. This study investigated the filed frequency of pre- harvest sprouting of 242 varieties and lines, including approved wheat varieties in Sichuan since 2000 and regional tested in Sichuan from 2017 to 2018, which would become new varieties in recent years. It was found that there were 23 (9.5%) and 67 (27.7%) materials, respectively, which were likely to have strong pre- harvest sprouting resistance (pre- harvest sprouting rate less than 5%) and high pre-harvest sprouting resistance (between 5% and 15%). This provided references for parent selection of pre-harvest sprouting resistance breeding, and found the difference in the pre-harvest sprouting resistance of different materials: the varieties approved since 2000 < regional tested common wheat lines < early sowing early mature wheat lines < special purpose wheat lines. The pre-harvest sprouting resistance of the varieties would increase in the next few years. Seed color had strong influence on pre-harvest sprouting resistance. The darker the seed color, the stronger the resistance of the pre-harvest sprouting. However, there were still 3 white wheat materials‘( Chuanyu26’,‘Chuanfu9’and‘Chuanfu17’) which had strong pre-harvest sprouting resistance, and could be evidence for white seed wheat breeding of preharvest sprouting resistance. In addition, we found that the early sowing might increase the resistance of preharvest sprouting of wheat varieties in Sichuan.

  Seawater Stress on Seed Germination and Physiological-Biochemical Index in Seedling Stage of‘Black Wheat 76’ 2019, 35 (5):  7-11.  DOI: 10.11924/j.issn.1000-6850.casb17120059 Abstract + ( 582 )   PDF ( 1348KB )   ( 417 ) To study the effect of seawater on‘black wheat 76’, we utilize seawater of different concentrations to treat the seed of‘black wheat 76’, and investigate the situation of seed germination and seedling growth after 5 days. The results indicated that seawater concentration of 5% , 10% and 20% could promote seed germination lightly, when the concentration was between 30% and 40%, the seed germination percentage, germinative force and germination index appeared a downtrend with the increase of the concentration. Seedling length, root length, seedling fresh weight and root fresh weight increased and then decreased with the increase of seawater concentration, and there were respective regulation mechanisms to control seedling length, root length, seedling fresh weight and root fresh weight, which needed further study. The activity of SOD、POD、 CAT and the content of MDA and chlorophyll in the leaf were measured, and the results showed that the activity of SOD increased firstly and then decreased with the increase of seawater concentration, and reached the highest when the concentration was 10%, and decreased sharply when the concentration was higher than 10% ; the activity of POD increased sharply, and reached the highest at concentration of 30% , and then decreased; the activity of CAT increased firstly and then decreased, reached the peak at the concentration of 5% , then decreased gradually; the MDA content assumed a trend of increasing; the chlorophyll content assumed a trend of decreasing gradually.

  Artificial Aging Treatment of Elymus sibiricus: Effects on Seed Vigor and Prolamin Constitutes 祁娟,何丽娟,吴召林,金鑫,陈永岗 and 师尚礼 2019, 35 (5):  12-17.  DOI: 10.11924/j.issn.1000-6850.casb18090003 Abstract + ( 623 )   PDF ( 1659KB )   ( 456 ) To reveal the effects of artificial aging on seed vigor, and constitutes and expression of prolamin, the Elymus sibiricus seeds were used as the tested materials. The seeds were treated with the method of high temperature (45℃) and high humidity (100% RH). The germination experiment was conducted on the seeds with different artificial aging degrees and the corresponding germination indexes were calculated. The acidacrylamide gel electrophoresis (A- PAGE) detecting prolamin was optimized at the same time. The results showed that the seed germination rate, germination potential, germination index, and vigor index decreased by 58% , 56.34% , 75.36% , and 83% after artificial aging for seven days. According to the results of gel electrophoresis system, the optimal system was determined as 300 V voltage, 10 μL loading volume, and 18% polyacrylamide gel. The band of prolamin in the ω-zones changed after artificial aging, such as the absence of the original bands and the appearance of new bands. Therefore, the seed vigor index is the most sensitive indicator to aging treatment, and the decrease of seed vigor is related to the change of conductivity. And the lose of seed vigor is companied with the absence of the original band and the appearance of new bands, indicating that the seed vigor is related to the changes of ω-prolamin.

  Temporal and Spatial Characteristics of Crop Planting Structure in Liaoning Province 2019, 35 (5):  18-25.  DOI: 10.11924/j.issn.1000-6850.casb18060115 Abstract + ( 1093 )   PDF ( 1607KB )   ( 414 ) To improve the agricultural economic benefit of Liaoning Province, we take 2001-2014 statistical data of crops as the data source, used mathematical statistics and GIS spatial analysis method to analyze temporal and spatial variations of sown area of five major grain and economic crops including corn, rice, soybean, oil and vegetable. The results showed that (1) from 2001 to 2014, the total sown area of crop in Liaoning Province increased by 16.97%, and the sown area of grain crops and economic crops increased by 17.30% and 15.85% respectively, and grain crops always accounted for a large proportion of total crop cultivation area, approximately 77.50%; (2) the sown area of corn increased by 70.54%, the planting proportion increased year by year, the sown area of rice decreased by 79.62%, the sown area of oil crops increased by 33.4%, the sown area of vegetables increased by 14.73%, and the sown area of soybeans decreased by 63.36%, the increased areas concentrated in the central and northern regions of Liaoning, such as Shenyang, Tieling and Jinzhou; (3)through GIS spatial analysis of the sown area of five major crops in Liaoning Province, it was found that there was some spatial agglomeration in distribution, the planting structure of corn, rice, oil and vegetables showed a radiation distribution from Shenyang to the west and north, while the planting area of soybean mainly concentrated in Dalian and Shenyang.

  The Molecular Marker Checking System for Genetic Population Construction 岳效飞,,雷奇,,,陈雪祎 and 杨雪琼 2019, 35 (5):  26-30.  DOI: 10.11924/j.issn.1000-6850.casb18080087 Abstract + ( 661 )   PDF ( 1753KB )   ( 406 ) To establish a molecular marker detection system for genetic population construction, a four-step detection system was constructed using SSR molecular marker technology, including DNA extraction, primer polymorphism screening, PCR amplification of parents and offspring, and electrophoresis detection of amplified products. In the experiment, only one pair of primers HvWaxy4 located on barley 7H chromosome was used to detect 7 F1 progenies, three of them were F1 progenies and four were self-pollinated progenies. The results indicated that SSR marker technology was feasible to verify the F1 hybrid plants in the process of genetic population construction, and the method was suitable to detect the authenticity of F1 plants in the process of self-pollinated crops.

  Arbuscular Mycorrhizal Fungus Affects the Photosynthetic Characteristics and Mineral Element Concentration of Blueberry Under Drought Stress 2019, 35 (5):  31-35.  DOI: 10.11924/j.issn.1000-6850.casb18090109 Abstract + ( 579 )   PDF ( 1230KB )   ( 411 ) For further clarifying the drought-resistant mechanism of blueberry improved by the arbuscular mycorrhizal (AM) fungus Glomus mosseae, a pot experiment was conducted to study the effects of AM fungus on the photosynthetic characteristics and mineral element concentrations in the leaves of southern highbush blueberry ‘O’ Neal’(Vaccinium corymbosum) under moderate drought stress. The results showed that moderate drought treatment significantly decreased the mycorrhizal colonization rate, net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs), original light energy conversion efficiency of PSII (Fv/Fm), phosphorus (P), magnesium (Mg) and iron (Fe) concentration in the leaves of blueberry. Under moderate drought stress, AM inoculation significantly enhanced leaf chlorophyll and carotenoid concentrations, Pn, Tr, Gs, intercellular CO2 concentration (Ci), Fv/Fm, concentration of P, Mg and Fe, but it had no significant effect on potassium (K) and manganese (Mn) concentration in the leaves of blueberry. Thus, moderate drought stress treatment inhibits the rate of photosynthesis in blueberry mainly through the non-stomatal factors such as decreasing the light energy conversion efficiency of PSII. However, under moderate drought stress, AM inoculation enhances photosynthetic efficiency of blueberry through both non-stomatal and stomatal factors,

  Color Leaf Landscape New Varieties Tree Populus euramericana cv‘. Hongxia’: Study on Photosynthetic Capacity 2019, 35 (5):  36-40.  DOI: 10.11924/j.issn.1000-6850.casb18080081 Abstract + ( 605 )   PDF ( 1368KB )   ( 350 ) The paper aims to explore the photosynthetic capacity of Populus euramericana cv‘. Hongxia’. The author measured the photosynthetic indexes of Populus euramericana cv.‘Hongxia’by Li- 6400 portable photosynthetic meter, plotted the light response curve and the diurnal variation map of photosynthetic index, and fitted and calculated the light response curve by modified rectangular hyperbola, compared with the Populus spp and Populus euramericana cv‘. Quanhong’. The results showed that: from the perspectives of the line distribution position, the light compensation point (LCP), light saturation point (LSP), apparent quantum yield (AQY), maximum net photosynthetic rate (Pnmax) and net photosynthesis rates (Pn) under the same light intensity, the photosynthetic capacity of Populus euramericana cv‘. Hongxia’was poor, and it was not as good as that of the similar trees Populus spp and Populus euramericana cv‘. Quanhong’; the diurnal variation curves of the net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductivity (Gs) and stomatal CO2 concentration (Ci) were relatively stable with no obvious peak value, and the response to light stress was weak and the self-regulation ability was poor.

  Extraction and Measurement Methods of Carotenoids from Pepper Fruit 2019, 35 (5):  41-48.  DOI: 10.11924/j.issn.1000-6850.casb17110011 Abstract + ( 728 )   PDF ( 1385KB )   ( 269 ) The study aims to explore and optimize the extraction of carotenoids from pepper fruit and highperformance liquid chromatography (HPLC) detection system. Mature pepper fruits were used as materials, by using single factor experiment and L9(33) orthogonal test, the main five factors including extraction solvent, the ratio of solid to liquid, extraction temperature, time and pretreatment method to the raw materials were discussed. And then the types of mobile phase, ratio and flow fate were also optimized. The results showed that by using dichloromethane-ethyl alcohol (V: V = 1:1) as extraction solvent, the material to liquid ratio of 1:18, extraction temperature and time of 50℃ and 60 min, the yield of carotenoids was the highest. Using L600-2 HPLC, the main components of carotenoids in pepper fruit could be identified by the optimized chromatographic condition such as: methanol and acetonitrile as mobile phase A (V: V =55:45), 100% methyl tertiary butyl ether as mobile phase B and VA: VB=90: 10, 1.0 mL/min of flow rate and 25℃ of column temperature, 20 μL of sample quantity, respectively. This optimized carotenoids extraction method and HPLC determination method are easily operated, have high productivity and good repeatability, and can provide a reference for the extraction and determination of carotenoids from pepper fruit in the future.

  Expression Profiling of Cold-responsive MicroRNA in Banana 2019, 35 (5):  49-57.  DOI: 10.11924/j.issn.1000-6850.casb18100007 Abstract + ( 563 )   PDF ( 1278KB )   ( 318 ) To explore the potential roles of miRNA in banana under cold stress, weSanalyzed their dynamic expression of cold responsive miRNAs in banana. The expression profiling of cold-responsive miRNAs in banana leaves was detected by stem-loop qRT-PCR after 0, 2, 4, 8 , 12 and 24 h of cold stress at 5°C. The results showed that fifteen potential cold-responsive miRNA were expressed and exhibited different expression patterns at different treatment stages. The 15 miRNA were divided into four groups according to their expression pattern. Generally, the expressions of Group I (miR159e, miR159f, miR160-3p, miR397a, miR399j, miR408, miR5179, miR530, miR535 and miR5538) and II (miR164e and miR444a) were upregulated at 5°C cold stress. During the cold stress, the average expression level of these miRNA was higher than the control (0 h). miR156l, miR162a and miR166a were in Group III, and their expression was reduced during the whole period of the cold treatment. Group IV had only one miRNA (miR156a). Its expression was significantly increased only at 12 h and reduced at the rest of the time points under cold stress. The analysis on the target genes of these miRNA revealed that these miRNA participated in the signal transduction, growth and development and stress response under abiotic stress. These findings provide valuable information for further functional characterization of miRNA associated with cold stress in banana.

  Comparison of Photosynthetic Parameters of Walnut Varieties 2019, 35 (5):  58-63.  DOI: 10.11924/j.issn.1000-6850.casb18010085 Abstract + ( 632 )   PDF ( 1356KB )   ( 353 ) For efficient planting of walnut, we took 11 varieties planted in Longnan area of Gansu as research subjects to study the differences of photosynthetic response. By using an automated light curve program in the LI- 6400 portable photosynthesis analysis system (LI- COR, Lincoln, Nebraska, USA), we analyzed the differences of light saturation point (LSP ), light compensation point (LCP ), net photosynthetic rate (Pn ), maximum net photosynthetic rate (A max), dark respiration rate (Rd ), intercellular CO2 concentration (Ci ), stomatal conductance (Gs ), transpiration rate (Tr ), apparent quantum yield (AQY ) and other parameters of the 11 varieties. The results showed that: the photosynthetic efficiency ranked as‘Vina’>‘Yuanfeng’>‘Shanhe No.5’>‘Chandler’>‘Wen 185’>‘Xiluo No.3’>‘Xiangling’>‘Qingxiang’>‘Qieke’>‘Xiluo No.2’>‘Jing 861’. Among the 11 varieties, the light intensity of‘Vina’adapted to a wide range and was suitable for close planting in both strong and low light ondition; ‘Yuanfeng’ and ‘Shanhe No.5’ were suitable for close planting under strong light condition;‘Chandler’had a strong adaptability and could be properly close planted under strong light condition; the planting space of‘Qieke’and‘Xiluo No.2’should be carefully maintained as their light intensity adaptability was narrow,‘Qieke’was suitable for planting in areas with strong sunlight while‘Xiluo No.2’was suitable for areas with weak light;‘Xiluo No.3’,‘Qingxiang’and‘Xiangling’had high weak light utilization efficiency and were more suitable for close planting under low light condition. Among the 11 varieties, the shade tolerance of‘Jing 861’is the best and suitable for close planting in the areas with weak light intensity.

  Hemerocallis fulva: Direct Induction of Adventitious Bud and Plant Regeneration 2019, 35 (5):  64-69.  DOI: 10.11924/j.issn.1000-6850.casb17090078 Abstract + ( 584 )   PDF ( 1711KB )   ( 282 ) The purpose of this study is to induce adventitious buds directly from young shoots rather than callus, and establish the regeneration system of Hemerocallis fulva. The young shoots of Hemerocallis fulva‘32- 1’were used as explants, the culture medium with different hormones and activated carbon was prepared. The effects of every factor on plant regeneration of Hemerocallis fulva were studied. The results showed that different matching of hormones had significant difference on primary culture, multiplication and rooting culture of Hemerocallis fulva‘32-1’. The optimum initiation medium was MS+6-BA 3.0 mg/L+NAA 2.0 mg/L, the initiation rate and proliferation coefficient was 100.00% and 5.60, respectively, and this medium could induce the adventitious buds directly. The optimal multiplication medium was MS+6-BA 2.0 mg/L+NAA 0.5 mg/L, and the multiplication coefficient was 3.47. The appropriate rooting medium was 1/2MS+NAA 1 mg/L+AC 2 g/L.

  The Germination Characteristics of Amomumtsao-ko Seed 2019, 35 (5):  70-74.  DOI: 10.11924/j.issn.1000-6850.casb17100025 Abstract + ( 613 )   PDF ( 1371KB )   ( 393 ) To provide a reference for quality test and improving the success rate of sowing and seedling of Amomumtsao- ko seed, we investigated its dormancy causes and optimum germination condition. The water，permeability was measured by weighing method after soaking seeds; the germination inhibitor was detected by biological assay; the germination test was conducted under the following conditions: different preliminary treatments, different light and temperature, different germinating beds as well as different storage methods, to measure the germination rate. The results showed that Amomumtsao- ko seed had low water absorption, only 40% after 67 h; the aqueous extracts of Amomumtsao- ko seed inhibited the germination of cabbage seeds obviously; the germination rate and uniformity of the seeds treated by wet sand lamination for 30 d were improved significantly and the germination rate increased by 50% comparing with the untreated seeds; using gauze as the germination bed, Amomumtsao-ko seed had the highest germination rate under 12 h light and 30/ 20℃ alternating condition, up to 54.75%. The germination inhibitors in the seed might be one of the main causes of dormancy; wet sand lamination treatment could effectively degrade the germination inhibitors, therefore, it was the optimum pretreatment method. 12 h light, 30/20℃ alternating condition and gauze as the germination bed is the optimum germination condition; wet sand storage is the optimum storage method.

  Butterfly in Ailaoshan National Natural Reserve: Faunal Composition and Species Diversity 2019, 35 (5):  75-83.  DOI: 10.11924/j.issn.1000-6850.casb18080017 Abstract + ( 705 )   PDF ( 1301KB )   ( 855 ) The paper aims to define the resources and faunal composition of butterfly and provide conservation strategy for the diversity protection in Ailaoshan national nature reserve. By the line transect method, we carried out 12 elementary resource surveys in 5 different habitats of the reserve from April 2016 to October 2017. The results showed that: 5967 butterflies were observed, collected and classified into 133 species which belonged to 75 genera in 5 families; Nymphalidae was the largest family, followed by Pieridae and Lycaenidae; Zhangjiazhai had the laregest amount of genus and species of butterflies among the 5 different habitates; the diversity results also showed that: Nymphalidae and bufferzone Zhangjiazhai (A2) had higher species diversity, genus diversity, species richness; the similarity of butterflies among the 5 different habitats of Ailaoshan was low; faunal composition of butterfly in Ailaoshan was mainly composed of oriential species with 101 species which occupied 75.94%. 87% species and 73% individuals of butterfly distributing below altitude 1100 m also indicated evident vertical distribution of butterflies in Ailaoshan. There are obvious differences in butterfly diversity in different habitats, and the study lays a foundation for the observation of butterfly diversity at large scale.

  Soil Ecological Stoichiometric Characteristics of Different Land Types in Karst Valley Area of Zhongliang Mountain 2019, 35 (5):  84-92.  DOI: 10.11924/j.issn.1000-6850.casb18030080 Abstract + ( 726 )   PDF ( 1272KB )   ( 326 ) To elucidate the spatial distribution characteristics of soil nutrients in different land types and their influencing factors in Karst valley region, the authors explored the soil ecological stoichiometric characteristics and the distribution of farmland, grassland and forest in the Zhongliang Mountain trough valley area. The soils of different land-use-types and soil depths (0-15, 15-30 and 30-45 cm) were selected to analyze their soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP) content based on geostatistic approach and laboratory analysis. The results showed that the average value of SOC, TN and TP in the three soil types was 20587.8, 1472.8 and 598.9 mg/kg, respectively. The variation of SOC and TN was larger, and the TP variability was smaller. The content of soil C, N and P decreased with the increase of soil depth. The content of SOC and TN was: forest＞wild grassland＞farmland; TP content was: farmland＞wild grassland＞forest. The spatial variation of soil C/N, C/P and N/P were large (CV>28%), and the changing range of C/N value was 5.04 to 41.2, with an average value of 14.1. The changing range of C/P value was 11.02 to 105.42 and the mean value was 37.28.The changing range of N/P value was 0.99 to 6.32, with an average value of 2.71. There was no significant difference in soil C/N among different land types but significant difference in C/P and N/P. The value of C/N was forest＞farmland＞wild grassland, and C/P, N/P value showed a different trend as forest＞ wild grassland＞farmland. There was a significant correlation between SOC, TN and TP in farmland soil (P < 0.01). The correlations between TN and TP, SOC and TP of wild grassland and forest were not obvious. The content of C, N, P and its ecological stoichiometry were influenced by the soil physical and chemical properties, land types and human activities. The analysis of soil physical and chemical properties showed that soil TN, SOC and available nitrogen were the main factors affecting soil C/N, C/P and N/P value. The soil C, N, P content and C/N/P value in the Karst trough valley of Zhongliang Mountain were influenced by land types, soil physical and chemical properties, human activities and other factors with large spatial variability. In actual land use, soil nutrient loss could be reduced by scientific and rational use of land according to local conditions.

  Tillage Modes and Nitrogen Fertilization Rates Affect Yield Component and Population Quality in Wheat Following Rice 2019, 35 (5):  93-99.  DOI: 10.11924/j.issn.1000-6850.casb18080072 Abstract + ( 646 )   PDF ( 1293KB )   ( 306 ) In a field experiment under the condition of rice straw returning, we took wheat variety‘Sumai 188’ as the material and investigated the effects of different tillage modes and nitrogen fertilization rates on wheat yield component and population quality, to provide reference for large area mechanized cultivation of wheat following rice. There were 3 tillage managements, including no-tillage, rotary-tillage and ploughing, as well as 3 nitrogen fertilization rates including 210 kg/hm2, 240 kg/hm2, 270 kg/hm2. The results showed that: the wheat yield under no-tillage was significantly higher than those under rotary-tillage and ploughing condition; the yield was improved gradually with the increase of nitrogen rates; a significant interaction effect was found between tillage modes and nitrogen rates on grain yield; compared with other tillage modes, wheat under notillage had higher grains per spike and 1000-grains weight, more tillers with lower percentage of earring- tillers, lower source- sink coordination, and better photosynthetic ability after the anthesis stage; with the increase of nitrogen rates, a consistent improvement was observed in spike number, grains per spike, tillage number, the percentage of earring-tillers, photosynthetic produce ability after the thesis stage, and source-sink coordination. These results suggest that appropriate increase of nitrogen fertilizers could improve grain yield by optimizing wheat population quality and synergistically enhancing yield components. The highest yield is achieved under the nitrogen rate of 270 kg/hm2 or 240 kg/hm2 under no-tillage mode.

  Effects of Continuous Rotation and No-till of Soybean-corn on Soil Nutrients and Crop Yield 2019, 35 (5):  100-106.  DOI: 10.11924/j.issn.1000-6850.casb18040044 Abstract + ( 625 )   PDF ( 1222KB )   ( 502 ) The objective of this study is to solve the problems such as yield loss of no-till, environmental pollution of straw burning and unreasonable plantation structure. A field experiment with two types of tillage [conventional tillage (CT) and no- till (NT)] from 2013 to 2016 was conducted to evaluate the effects of continuous rotation and no-till of corn-soybean on soil nutrients and crop yield. The results indicated that soil total nitrogen, total phosphorus, total potassium, available nitrogen, available phosphorus, available potassium, organic matter at 0-7.5, 7.5-15, 15-22.5, and 22.5-30 cm depth of NT were higher than that of CT. Tillage had significant effect on soil nutrient except total potassium. Tillage had significant impacts on soil bulk density. Soil bulk density was higher at each soil layer under no-till than that of conventional tillage. The difference of soil bulk density between 15-22.5 cm and 22.5-30 cm under no-till was not significant, while the difference among different layers under conventional tillage was significant. Soybean yield under no- till increased by 16.37% and 25.33% compared with that of conventional tillage in 2013 and 2015, respectively. Corn yield under no-till increased by 0.88% and 9.50% compared with that of conventional tillage in 2014 and 2016, respectively. Soybean- corn rotation and no- till saved the cost of 640 yuan/hm2, and increased the income of 2220 yuan/hm2 compared with conventional tillage.

  Distribution Characteristics of Soil Organic Nitrogen in Rhizosphere of Different Sugarbeet Genotypes 2019, 35 (5):  107-114.  DOI: 10.11924/j.issn.1000-6850.casb18090058 Abstract + ( 587 )   PDF ( 1357KB )   ( 426 ) Apart from inorganic nitrogen in soil, organic nitrogen is also an important nutrient source for plant growth and development. In order to ascertain the absorption and utilization of organic nitrogen in the rhizosphere and the spatial distribution of organic nitrogen components in the rhizosphere of different genotype sugar beet, one each of varieties with high and low organic nitrogen efficiency was selected. Using Kuchenbuch-Zhou''s miniature and field net bags, the variation regularities of organic nitrogen components in the rhizosphere of sugar beet seedlings and the whole growth period of the field were studied, and the mathematical model of soil nitrogen mineralization and the spatial distribution of each component in the rhizosphere was established. The results showed that the content of organic nitrogen in the rhizosphere soil of 2 weeks old seedlings was as follows: acid hydrolysis total nitrogen (ATN) > amino acid nitrogen (AAN) > ammonia nitrogen (AN) > amino sugar nitrogen (ASN). Among them, AAN and AN form obvious depletion surface in the rhizosphere, that is, the farther away from the root surface, the higher the content. The highest value is reached at 15mm from the root surface, and the subsequent changes become more stable. The distribution law can be obtained by the equation Y =Y0+Aln(X) fitting. The content of ASN is low, and it is not significant with the distance between the rhizosphere. The different sugarbeet varieties have different depletion ability to rhizosphere organic nitrogen, and the varieties with high organic nitrogen absorption efficiency are all Higher than the low variety. Under natural conditions in the field, the contents of ATN, AAN and AN in the rhizosphere soil of the beet grew fastest at the seedling stage, then slowly increased and gradually became constant. The results of laboratory and field experiments showed that the mineralization of soil organic nitrogen was lower than that of non-nitrogen treatment after nitrogen application, and the mineralization of rhizosphere soil organic nitrogen was higher than that of low variety.

  Optimization of Strawberry Fertilization Formula in Substrate Culture 2019, 35 (5):  115-121.  DOI: 10.11924/j.issn.1000-6850.casb18040061 Abstract + ( 631 )   PDF ( 1346KB )   ( 257 ) The objective is to solve the problems of unreasonable fertilizer input, fruit yield decrease and poor fruit quality under substrate cultivation of strawberry. Taking Fragaria × ananassa‘Benihoppe’as the experimental material, and farmer''s practice (FP) as the control, we studied the effects of the rate of recovering, plant height, stem diameter, leaf area, flowering budding rate, yield, quality and economic benefits of strawberry under substrate cultivation. Compared with the farmer''s practice (FP), the optimized fertilization (OPT) reduced the seedling time by 5-8 days, increased the seedling rate by 43.3%, the stem diameter by 20.4%, and the leaf area significantly by 77.1%. Compared with the FP, the OPT could significantly increase the fruit weight and fruit number of strawberry, and the yield of strawberry was increased by 40.9% , the average enhancement of strawberry acidity was 15.8%, and economic benefits of strawberry was improved by 53.2 yuan/m2.

  Climatic Suitability Analysis of Spring Sowing Zucchini in Guizhou 2019, 35 (5):  122-126.  DOI: 10.11924/j.issn.1000-6850.casb17090124 Abstract + ( 755 )   PDF ( 2194KB )   ( 199 ) The study aims to analyze the climatic suitability of spring sowing zucchini in Guizhou, and provide climatic references for planting promotion of zucchini. We selected the meteorological factors of zucchini during key growth period as indexes; used the meteorological data from 1981 to 2010 and spring drought days data from 1961 to 2015 of 83 stations in Guizhou, based on ANUSPIN and ArcGIS, to apply the thin plate spline function and inverse distance weighting methods to the interpolation of each factors, and then, classified and superposed each factors according to their suitable classes, and got the layer of comprehensive climatic suitability regionalization for zucchini. We got the distribution layers of temperature, precipitation, sunshine duration and other climatic factors of zucchini during key growth period, and the most suitable, sub-suitable, and suitable region for spring sowing zucchini in Guizhou. The most suitable region distributed in the east and southeast Guizhou, which had the most suitable meteorological condition and abundant precipitation during the fruiting period, and low risk of spring drought, all could be beneficial to high yield. The sub-suitable region distributed in the north and southwest Guizhou, which had different kinds of suitable meteorological conditions and some disadvantages as well, it was necessary to strengthen field management for high yield. The suitable region distributed in the northwest Guizhou, which had relatively inferior meteorological condition and high risk of spring drought, and high yield could be obtained only through facility cultivation and enhancing the control of temperature and humidity to make full use of sunshine resources.

  Drought Monitoring in the Huang-Huai-Hai Plain: Based on Meteorology and Remote Sensing 2019, 35 (5):  127-136.  DOI: 10.11924/j.issn.1000-6850.casb18090037 Abstract + ( 892 )   PDF ( 7167KB )   ( 207 ) The paper aims to carry on drought monitoring in the Huang-Huai-Hai plain comprehensively and systematically. We analyzed the drought spatial and temporal change in the Huang-Huai-Hai plain by using standard precipitation evapotranspiration index (SPEI) and temperature vegetation drought index (TVDI). The results showed that: there was a weak trend of drought in the Huang-Huai-Hai plain from 1960 to 2016, among them, the annual scale drought occurred in 12 years and the drought distribution was uneven in different regions; the Huang-Huai-Hai plain had the highest frequency of mild drought, followed by moderate drought; TVDI in the main growth period of winter wheat tended to be arid from 2001 to 2016; the drought levels and distribution ranges were different in different growth periods; the drought in February was severe and the distribution was wide, mainly concentrated in the northern and eastern parts of the study area; the intensity and area of drought decreased from March to May, mainly in southern Hebei and eastern and central Shandong. The results can detect and evaluate the drought conditions in the Huang- Huai- Hai plain and provide reference for agricultural production and drought prevention.

  Response of Myzus persicae to Flue-cured Tobacco Varieties and Micro-climate in Longyan 2019, 35 (5):  137-143.  DOI: 10.11924/j.issn.1000-6850.casb17110094 Abstract + ( 627 )   PDF ( 1400KB )   ( 215 ) The effects of different varieties of flue-cured tobacco on tobacco aphids [Myzus persicae (sulzer)] in Longyan was carried out from February to June in 2014. The result of the study showed winged tobacco aphids started to fly into tobacco fields in the first ten-day period of April. It is a fastigium in between the third ten-day period of April and the second ten-day period of May for tobacco aphids. Additionally, two fastigiums, bimodal curve, of tobacco aphids were also found. And the numbers of aphids rapidly declined in the third ten-day period of May and the first ten-day period of June. It was significantly correlative in between the temperatures of micro-climate in tobacco fields and the winged aphid densities or some winged aphid plant rates of Minyan 35 plants or the densities of mummy of Yunyan 87. Besides, it was significantly different for tobacco densities, some aphid plant rates, no-winged or mummy densities in tobacco fields. Especially, it was coherent between early spring tobacco group and spring tobacco group for the difference of mummy densities. Thus, it suggests the effects of aphids, winged aphids or mummy in tobacco fields depend on different varieties of flue-cured tobacco in Longyan. And it benefits to the seed selection of anti-aphid varieties and the control of tobacco aphids and the diseases by the transmission of them in tobacco fields.

  Cloning of Potato Phytophthora infestans RxLR Effector Gene RD24 and Constructing and Identifying of Its PVX Expression Vector 2019, 35 (5):  144-149.  DOI: 10.11924/j.issn.1000-6850.casb17120126 Abstract + ( 626 )   PDF ( 1433KB )   ( 389 ) The pathogen Phytophthora infestans, which causes potato late blight, delivers effectors inside the living host cells, the effector proteins play an important role for the infection of the pathogen, and are the critical reasons for the pathogen to suppress plant immunity. PITG_RD24 is one of the important effectors of P. infestans which is located in the nucleus of plant cell. To identify the transient expression and resistance of RD24 effector in potato, it is necessary to construct the expression vector of PVX·RD24 (pGR106·RD24). In this study, the fragment of RD24 is inserted to empty vector of pGR106 by the methods of PCR, restriction enzyme digestion and molecular cloning. Then the connected product and plasmid is transformed into DH10B Agrobacterium tumefaciens strains by heat shock method. The expression vector of pGR106 · RD24 is successfully obtained after PCR screening, plasmid extraction, contrasting sequence, and the study can provide the necessary vector for screening potato resistant genes.

  Physiological and Biochemical Indexes of Blood of Different-parity Dairy Cows 白若雨,王相国,,,,,李秋明, and 2019, 35 (5):  150-153.  DOI: 10.11924/j.issn.1000-6850.casb17120080 Abstract + ( 617 )   PDF ( 1185KB )   ( 282 ) The objectives are to better understand the change rule of blood physiological and biochemical indexes of different-parity dairy cows, thus to guide the practical production. Holstein cows of different parities with similar body conditions are chosen in this experiment. The blood routine indexes and blood biochemical indexes of Holstein cows are examined. The results showed that the number of white blood cells increased significantly in the 5th parity cows, obviously higher than that in the 2nd-4th parity cows (P ＜0.05). The number of erythrocytes in the 2nd-4th parity cows was significantly higher than that in the 5th parity and primiparous cows (P ＜0.05). However, the amount of hemoglobin in primiparous cows was higher than that in the 2nd-5th parity cows (P ＜0.05). Furthermore, the percentage of neutrophils in the 5th parity cows showed a significant rise (P ＜0.05). According to the blood biochemical results, ALKP content and calcium ion concentration in primiparous cows were significantly higher than those in the 2nd-4th parity cows (P ＜0.05), and the trends were all reduced gradually with the increase of parity. Thus, there are certain correlations between physiological and biochemical indexes and different parities. Our results will provide a basis for the breeding management of different-parity cows.

  Appropriate Energy Level for Lushi Green-shell Egg Laying Pullets During Growing Period 2019, 35 (5):  154-159.  DOI: 10.11924/j.issn.1000-6850.casb18010034 Abstract + ( 699 )   PDF ( 1205KB )   ( 200 ) This experiment was conducted to investigate the effects of different dietary energy levels on body measurements, growth performance and slaughter traits of growing Lushi green-shell egg laying pullets, and to gain the energy requirement of pullets. A total of 150 Lushi green-shell egg laying pullets with similar weight aged 8 weeks were randomly allocated to 5 groups, each of which included 5 replicates of 6 pullets. Five experimental diets were formulated based on ME content of A (10.52 MJ/kg), B (10.90 MJ/kg), C (11.29 MJ/kg), D (11.70 MJ/kg) and E (12.10 MJ/kg). A single factor experimental design was adopted. The pre-trial period was one week, and the trial period was ten weeks. The results showed that different energy levels had significant influence on shank length, chest width and chest depth of Lushi green-shell egg laying pullets (P ＜ 0.05). There was no significant difference between group D and E on final weight and ADG (P ＞0.05), but both were significantly higher than group A, B and C (P ＜0.05). When the ME (group E) was excessive, the final weight and ADG decreased. Different energy levels had significant influence on slaughter traits (P ＜0.05). It is concluded that ME 11.70 MJ/kg in this study could improve the growth performance and slaughter traits of Lushi green-shell egg laying pullets during the growing period.

  Feeding Bacteria: Effect on Phenoloxidase Activity and Its Gene Expression in Hemolymph of Bombyx mori 2019, 35 (5):  160-164.  DOI: 10.11924/j.issn.1000-6850.casb18030058 Abstract + ( 545 )   PDF ( 1308KB )   ( 206 ) To investigate the effect of bacteria infection on phenoloxidase activity and its gene expression in hemolymph of Bombyx mori, the real-time fluorescent quantitative PCR is applied to detect the expression of PPO1 and PPO2 in different time (6、12、24、48 h) after feeding Escherichia coli and Staphylococcus aureus, meanwhile the phenoloxidase activity is determined. The results showed that the expression of PPO1 and PPO2 increased at 6 h, 12 h and 24 h after oral infection with the two bacteria, the phenoloxidase activity was significantly higher than that of the control. In addition, the gene expression of PPO1 and PPO2 and the phenoloxidase activity reached peaks at 12 h after Escherichia coli infection, while they reached peaks at 24 h after Staphylococcus aureus infection. The phenoloxidase activity and gene expression were different after Gram positive bacteria and Gram negative bacteria infection, indicating that the immune mechanisms of silkworm induced by different bacteria were different.