Current issue

• 2020 Vol.36 No.6 Published:25 February 2020

  Allelochemicals: Effects on Growth Characteristics of Maize Seeds and Seedlings Yao Lan, Sa Rula, Fan Fu, Feng Rui, Wang Lijuan, Zhu Jian, Han Xiangyu 2020, 36 (6):  1-4.  DOI: 10.11924/j.issn.1000-6850.casb18110098 Abstract + ( 644 )   HTML ( 4 )   PDF ( 1299KB )   ( 99 ) The paper aims to study the effects of allelochemicals in straw on the germination of maize seeds and growth characteristics of seedlings. We set different concentrations of mixed acid solutions of p-hydroxybenzoic acid, phthalic acid, benzoic acid, syringic acid and vanillic acid as treatments, and cultivated maize seeds and seedlings, determined their physiological indexes by taking distilled water as control (CK). The results showed that: the mixed acid solutions significantly reduced the germination rate and radicle length of maize seeds; the mixed acid solutions of 100 mg/L, 200 mg/L and 500 mg/L significantly reduced hypocotyl length and the root activity of maize seedlings; the catalase activity of mixed acid solutions were higher than that of CK, and there was no significant difference; with the increase of mixed acid concentration, MDA content in maize leaves increased gradually. Mixed acid solution of above 50 mg/L concentration could inhibit the growth of maize seeds and seedlings.

  The Combining Ability and Genetic Parameters of Yield per Plant and Other Characters of 11 Maize Inbred Lines Hu Jun, Wei Kaifeng, Guo Pengcheng, Liu Wan, Yu Huilin, Pan Hongyu, Zhang Xinsheng 2020, 36 (6):  5-10.  DOI: 10.11924/j.issn.1000-6850.casb20190900592 Abstract + ( 540 )   HTML ( 3 )   PDF ( 1125KB )   ( 146 ) The combining ability, heritability and reciprocal effects of yield per plant and other characters of maize inbred lines were studied to provide a basis for the selection of maize inbred lines and the combination of maize hybrids. Using 11 maize inbred lines as test materials, we matched 110 combinations according to Griffing III complete diallel hybridization method. Seven phenotypic characters, i.e., yield per plant, plant height, ear height, branch number and spindle length of tassel, silking and anthesis stages of the inbred lines were observed, and the general combining ability (GCA), special combining ability (SCA), reciprocal effects (REC), broad-sense heritability (H 2B) and narrow-sense heritability (H 2N) of the above characters were estimated. The results showed that both GCA and SCA of all the tested traits were significantly different except the SCA of spindle length of tassel. The GCA of yield per plant of JZ3 and JZ6 inbred lines was significantly positive. Two pairs of the combinations, JZ9×JZ2 and JZ2×JZ9, JZ6×JZ3 and JZ3×JZ6, had the largest positive SCA effect values of 40.68 g and 35.24 g, respectively. The REC of yield per plant had significant difference; however, some inbred lines had large variances in the REC. The H 2B of the seven characters in the descending order was tassel branching number, plant height, the anthesis stage, ear height, the silking stage, yield per plant, and spindle length of tassel. The H 2N, ranging from big to small was tassel branching, plant height, ear height, the anthesis stage, spindle length of tassel, silking stage, and yield per plant. The results suggest that the dominant genetic variance accounts for the largest proportion, H 2N of yield per plant is the smallest; therefore, the yield per plant is easy to be affected by environmental conditions and suitable for selection in later generations. Because of the significant REC in yield per plant, the way of crossing in some inbred lines need to be strictly controlled.

  Effects of LED Spectrum Treatments at in vitro Culture Stage on the Growth and Minituber Production of Potato Plantlets After Transplanting in Greenhouse Chen Lili, Wang Haoying, Gong Xiaochen, Xue Xuzhang, Hu Yuegao 2020, 36 (6):  11-18.  DOI: 10.11924/j.issn.1000-6850.casb18110023 Abstract + ( 449 )   HTML ( 4 )   PDF ( 1347KB )   ( 212 ) The morphology of potato plantlets grown in vitro under different LED light sources varies obviously. To explore whether the variations will have lasting effects on potato plantlets’ growth after transplanting in greenhouse, a single-factor randomized block design test was conducted with 4-week-old potato plantlets grown in vitro under 100% red light (R), 100% blue light (B), 100% green light (G), 75% red light+ 25% blue light (RB), 45% red light+ 35% blue light+ 20% green light (RBG) and 100% white (CK) light spectrum being transplanted in greenhouse to observe their growth and tuberization performance. The results indicated that chlorophyll fluorescence Fv/Fm and qP, SPAD value and biomass accumulation of potato plantlets from B treatment were always higher than that of CK and other treatments; the biggest minituber dry weight and fresh weight and the proportion of effective minituber in B treatment were increased by 45.66%, 45.09% and 10.93%, respectively, compared with CK. R treatment increased the number of minituber per plantlet by 29.60% but decreased the proportion of effective minituber by 63.97%. The parameters including Fv/Fm, qP, qN, SPAD, biomass accumulation in different organs and minituber yield and yield composition of plantlets from combined spectrum RB and RBG showed no significant differences from that of CK. However, in terms of both growth and tuberization, plantlets from G treatment performed the worst after transplanting. Thus, the effects of monochromic red, blue and green LED spectrum on the growth and tuberization of potato plantlets grown in vitro continued after the plantlets’ transplanting in greenhouse, whereas the combined spectrum RB and RBG did not. Thus, in the cultivation of potato plantlets in vitro, monochromatic blue and red LED spectrum have potential application value as light sources to provide illumination and combined spectrum RB and RBG can be utilized as the alternatives of white light.

  Hydrogen Peroxide, Boric Acid and PEG-6000: Effects on the Germination of Sugar Beet Seeds Ma Yue, Wang Ronghua, Zhu Tengxiang, Wu Zedong, Liu Dali, Wang Maoqian 2020, 36 (6):  19-23.  DOI: 10.11924/j.issn.1000-6850.casb20190900595 Abstract + ( 508 )   HTML ( 2 )   PDF ( 1139KB )   ( 289 ) In order to research the influence of different initiator combinations on seed germination of sugar beet, and provide a basis for screening seed initiators, the sugar beet seeds of TD802 were used as the test material, different concentrations and different initiator combinations were adopted to treat the beet seeds, and the germination potential, germination rate, germination index and vigor index were measured. The results showed that initiators with different concentrations and combinations had different initiation effects at the same treatment time, the combination of 8% hydrogen peroxide and 40% PEG had the highest germination potential, 5% hydrogen peroxide had the highest germination rate, the combination of 3% hydrogen peroxide and 0.01% boric acid had the highest germination index, and the combination of 8% hydrogen peroxide and 0.01% boric acid had the highest vitality index.

  Effects of Biogas Fertilizer on Growth and Physiological Characteristics of Ligustrum × vicaryi Hort Jia Zhengmin 2020, 36 (6):  24-29.  DOI: 10.11924/j.issn.1000-6850.casb18110020 Abstract + ( 473 )   HTML ( 0 )   PDF ( 1186KB )   ( 233 ) The study clarifies the effect of different proportions of biogas fertilizer on Ligustrum × vicaryi growth and physiological characteristics, thus to provide a basis for the rational application of biogas to Ligustrum × vicaryi seedling cultivation. In field condition, 5 treatments were set as conventional fertilization (control, Z1), 25% biogas fertilizer (Z2), 50% biogas fertilizer (Z3), 75% biogas fertilizer (Z4), 100% biogas fertilizer (Z5), 3 repeats were conducted. The results showed that: for new treetop growth amount, Z4 was higher than control by 34.73% and Z2 by 6.89%; the chlorophyll content of Z4 was higher than that of Z1 in July and August by 35.00% and 64.71%, and that of Z5 was higher than Z1 by 20.00% and 47.06%; the root activity of Z4 and Z5 treatment was higher than Z1 by 55.26% and 50.00% in August; water use efficiency of Z4 treatment was higher than Z1 by 53.45%, 49.61% and 60.06% in June, July and August, there was no significant difference between Z2 and Z1; POD activity had no significant difference among all treatments in May, while that of Z4 was higher than Z1 by 25.34%, 32.51% and 42.21% in June, July and August; SOD activity had no significant difference among all treatments in April and May, while that of Z4 was higher than Z1 by 42.29%, 39.08% and 34.29% in June, July and August. According to the comprehensive analysis, Z4 is the best treatment on promoting growth and physiological characteristics of Ligustrum × vicaryi.

  Influences of Application of Mushroom Residue on Lettuce Growth, Soil Nutrients and Enzyme Activities Teng Qing, Zeng Mengfeng, Lin Huifan, Xie Yuqing 2020, 36 (6):  30-36.  DOI: 10.11924/j.issn.1000-6850.casb18100082 Abstract + ( 435 )   HTML ( 2 )   PDF ( 1219KB )   ( 92 ) To investigate the fertilizer efficiency of mushroom residue and its impact on the ecological environment, a pot experiment was conducted to study the influences of mushroom residue application on lettuce growth, soil nutrients, soil enzyme activities and soil microorganisms. The experiment had four treatments: blank treatment, mushroom residue, composite chemical fertilizer and mushroom residue + compound chemical fertilizer. The results showed that: (1) the application of mushroom residue could promote the growth of green pepper, the promotion effect on lettuce was not as good as that of chemical fertilizer; (2) the application of mushroom residue and compound fertilizer could significantly increase the soil nutrients, compared with the blank treatment, application of mushroom residue increased the soil total nitrogen by 58.6%, the alkali nitrogen increased by 73.3% and the nitrate nitrogen increased by 35.3%; (3) the application of mushroom residue significantly increased soil enzyme activities and soil microbial population, the soil catalase activity, dehydrogenase activity and urease activity of mushroom residue treatment was 1.31, 1.40 and 1.44 times as that of chemical fertilizer treatment, respectively, and the number of soil bacteria, actinomycetes and fungi was 1.56, 1.72 and 1.72 times, respectively. The application of mushroom residue could improve soil nutrient, soil organic matter, soil enzyme activity and soil microorganism, reduce nutrient loss and improve soil ecological environment.

  Cadmium Absorption and Enrichment in Wheat and Its Cadmium Pollution Prediction: Research Progress Fu Yuncong, Zhu Xiaolong, Yuan Cui, Xie Xiaolu, Li Pengxiang, Zhu Wei, Li Hongliang, Liu Daihuan 2020, 36 (6):  37-41.  DOI: 10.11924/j.issn.1000-6850.casb18100099 Abstract + ( 886 )   HTML ( 17 )   PDF ( 1113KB )   ( 188 ) We reviewed and summarized the general research progress of absorption and enrichment characteristics of cadmium in wheat, and analyzed the enrichment coefficient of cadmium in different parts of wheat. The results showed that: the cadmium enrichment in different parts of wheat was in the order of root>leaf>stem>seed. The safety threshold of soil cadmium was an important index to ensure the quality of wheat. The content of cadmium in wheat grain could be predicted by the total cadmium content and pH value in soil. The soil available cadmium extracted by 3 kinds of extractants was discussed, and it was found that the correlation coefficients (r) between the soil available cadmium extracted by these extractants and cadmium in wheat grain were in the order: complexing agents>neutral salts (CaCl2)>dilute (weak) acids. At last, we put forward references for future wheat cadmium pollution prediction.

  Calligonum mongolicum in Different Habitats of Sand Dunes in the Desert-oasis Ecotone of Hexi Corridor: Population Expansion Characteristics Liu Yujiao, Wang Guohua 2020, 36 (6):  42-47.  DOI: 10.11924/j.issn.1000-6850.casb18110022 Abstract + ( 585 )   HTML ( 0 )   PDF ( 1272KB )   ( 92 ) Taking Calligonum mongolicum, a key natural sand fixing plant in the desert-oasis ecotone of Hexi corridor, as the research object, we investigated the population expansion characteristics of Calligonum mongolicum at different habitants (mobile and stabilized dunes), to understand the population expansion characteristics of Calligonum mongolicum and its adaptive countermeasures to drought and high temperature in a more comprehensive way. The results showed that: (1) there were significant differences of population expansion of Calligonum mongolicum in different habitats; in mobile sand dunes, the lowland and ecotone, the population expansion was mainly dominated by sexual reproduction, and was supplemented by asexual reproduction, but was mainly dominated by asexual reproduction at the windward and the leeward slopes; with the fixation of mobile sand dunes, the population was dominated by sexual reproduction, the number and proportion of asexual reproduction decreased significantly, resulting in population decrease; (2) in different habitats, the population density of Calligonum mongolicum had a significantly negative relationship with its age; the population was dominated by young seedlings, and the oldest age (36-year-old) of the population appeared in the hilly lowlands; (3) the rhizomes in mobile sand dunes in different habitats were mainly 2 years old, and the length of perennial rhizomes was shorter; the age structure of rhizomes in different habitats of stabilized sand dunes was more balanced.

  Ziziphus jujuba (Mill.) Forest in Loess Area of Northern Shaanxi: Change of Soil Physical Properties Zong Qiaoyu, Ai Ning, Yang Fengmao, Qiang Dahong, Li Yang, Liu Jiao, Hao Baobao, Liu Changhai 2020, 36 (6):  48-56.  DOI: 10.11924/j.issn.1000-6850.casb20190900622 Abstract + ( 488 )   HTML ( 0 )   PDF ( 1353KB )   ( 265 ) To understand the differences in soil physical properties and soil structure of jujube forests in loess area of northern Shaanxi and provide references for jujube forest construction, regional forestry economic development and vegetation restoration, taking jujube forest in Mazhen, Shenmu as the main research object, we determined the soil physical properties by ring immersion method, and analyzed the spatial distribution characteristics of soil physical properties. The results showed that: (1) there were significant differences in soil physical properties among different vegetation types (P<0.05); the order of soil moisture was grassland>jujube forest in mountain>apricot forest; the maximum water holding capacity and capillary water holding capacity were apricot forest>jujube forest in mountain>grassland; (2) there were significant differences of soil water holding capacity and soil porosity of jujube trees of different forest ages (P<0.05); the water holding capacity of the 20-year-old jujube trees in beach was better than that of the 100-year-old jujube trees in beach, but the soil structure of the 20-year-old jujube trees in beach was worse than that of the 100-year-old jujube trees in beach; (3) the soil water holding capacity and porosity of jujube trees in mountain and beach were significantly different (P<0.05), and the soil bulk density was not significantly different (P>0.05); the soil water content of jujube trees in mountain and beach reached the maximum at soil layer of 60-100 cm, and their maximum values were 10.38% and 19.65%, respectively.

  Spatial and Temporal Evolution Characteristics of Negative Accumulated Temperature in Shiyang River Basin Ding Wenkui, Zhang Jinxiu, Yang Xiaoling, Wang Heling 2020, 36 (6):  57-63.  DOI: 10.11924/j.issn.1000-6850.casb18100120 Abstract + ( 544 )   HTML ( 0 )   PDF ( 1603KB )   ( 228 ) Using daily average temperature of five meteorological stations in Shiyang River Basin from 1960 to 2017, we analyzed spatial and temporal distribution characteristics of negative accumulated temperature and its relationship with temperature and frozen soil by linear trend coefficient method, ANOVA cycle method, accumulative anomaly and signal-to-noise ratio method. The results showed that the negative accumulated temperature of Shiyang River Basin was affected by altitude, landform, vegetation and weather system, and had obvious regional characteristics, the average and extreme value of the negative accumulated temperature was the highest in oasis plain, followed by that in desert area and mountain area. The negative accumulated temperature of normal years was the most, the probability was over 60%, and declined rapidly to both ends. The annual and decadal negative accumulated temperature showed increasing trends, and the increasing trend was the most obvious in Gulang. Time series quasi-period of the annual negative accumulated temperature was 7-9 years. The negative accumulated temperature in Gulang had an abrupt change in 1986, and there was no abrupt climate change in other regions. The starting and ending date and the emergence period of the negative accumulated temperature had certain differences, the earliest starting date (September 2, 1972) and the latest ending date (June 9, 1969) of the negative accumulated temperature all appeared in Tianzhu. The longest negative accumulated temperature period was 258 d (1972) in Tianzhu and the shortest was 100 d (2001) in Minqin. There was a very significant positive correlation between annual negative accumulated temperature and annual temperature in Shiyang River Basin, and the rise of the negative accumulated temperature had a good synchronous with annual temperature. Response of frozen soil change to the negative accumulated temperature was sensitive in Shiyang River Basin, with the increase of the negative accumulated temperature of 100℃, the frozen soil days decreased by about 6.2 d, the average frozen soil depth decreasesd by 4.5 cm and the maximum frozen soil depth decreased by about 6.9 cm.

  Antennal Morphology and Sensilla Distribution of Scambus brevicornis with Scanning Electron Microscopy Observation Zhao Hongying, Sun Yan, Wang Qi 2020, 36 (6):  64-68.  DOI: 10.11924/j.issn.1000-6850.casb20190900613 Abstract + ( 639 )   HTML ( 0 )   PDF ( 9554KB )   ( 139 ) To study the external morphology and the type of sensilla of adult Scambus brevicornis’s antennae, the sex difference was compared by scanning electron microscope. The results showed that the antennae of the adult S. brevicornis was flagelliform and the antennae were composed of scape, pedicle and flagellum. The female adult had 21 subsegments and the male adult had 25 subsegments. There were six sensillas on the adult antennae, including sensilla trichodea, sensilla placodea, sensilla coeloconica, sensilla chaetica, B?hm bristles and sensilla campaniformia. There were sexual differences in the density between male and female adults.

  Comparison of DNA Extraction of Different Tartary Buckwheat Parts After Drying and Screening of SSR Primers Related to Thin Shell Characters Yin Guifang, Li Chunhua, Sun Daowang, Lu Wenjie, Wang Yanqing, Wang Lihua 2020, 36 (6):  69-73.  DOI: 10.11924/j.issn.1000-6850.casb18100116 Abstract + ( 489 )   HTML ( 1 )   PDF ( 1301KB )   ( 56 ) The study aims to provide a basis for expanding the range of DNA extraction materials of tartary buckwheat, and to screen thin shell traits-related SSR primers, thus to lay a foundation for molecular markers of specific traits. Six parts of tartary buckwheat plants were used as materials for genomic DNA extraction, including cotyledons, tender stems, tender leaves, old leaves, old stems and petioles, and genomic DNA extraction was carried out using the plant DNA extraction kit after the materials were dried in an oven at 40℃. The quality, concentration and purity of DNA were detected. A total of 700 pairs of SSR primers were used for PCR amplification to screen thin shell traits-related SSR primers of tartary buckwheat. The results showed that the highest DNA concentration was obtained from the cotyledons (70.6 ng/μL), followed by tender stems (69.6 ng/μL); and lower NDA concentrations were obtained from the old stems and the petioles, which were 20.0 ng/μL and 7.2 ng/μL, respectively. The gel electrophoresis bands of DNA extracted from the cotyledons, the tender stems, the tender leaves and the old leaves were clear, while gel electrophoresis bands of DNA extracted from the old stems and the petioles were dark. Regarding the SSR amplification effect, except petioles, the cotyledons, the tender stems, the tender leaves, the old leaves and the old stems could meet the requirements of amplification without significant difference, and they could be used in subsequent molecular experiments. The DNA concentrations from dried tissues were not as high as those from fresh tissues, but the subsequent molecular experiments were not affected, except petioles. A pair of SSR primers with diversity was preliminarily screened in thin-shell tartary buckwheat and thick-shell tartary buckwheat.

  Diversity Analysis of Prokaryotic Microorganism of Farmland Soil: Bailang Village, Linzhou County, Lhasa Jin Guimei, De Ji, Yang Sang, Baima quwang, Gesang yuzhen, Guo Xiaofang 2020, 36 (6):  74-81.  DOI: 10.11924/j.issn.1000-6850.casb18110035 Abstract + ( 481 )   HTML ( 0 )   PDF ( 1266KB )   ( 66 ) The paper aims to explore the differences of microflora composition structure among different farmland types by studying the microorganism diversity of farmland soil in Linzhou, Lhasa. We isolated bacteria and actinomycetes from farmland soil and analyzed the 16S rDNA sequence, combined with the classic classification, we classified and identified the obtained strains, and finally determined the microflora composition structure of farmland soil. The results showed that soil bacteria were classified into 6 genera and 15 species, and actinomycetes were divided into 13 species; the occurrence frequency and relative abundance indicated that the dominant bacteria in soil were Bacillus cereus and Bacillus simple, however the dominant actinomyces were Streptomyces pseudogriseolus, Streptomyces ciscaucasicus and Streptomyces flavogriseus. Crop types have no significant influence on community composition of bacteria and actinomyces from farmland soil in Bailang village, Linzhou County.

  The Genetic Relationship and Diversity of 87 Mid-matured Cotton Germplasm Resources Zhang Yanbo, Yin Guo, Lu Zhengying, Sun Lu, Li Shiyun, Yang Yufeng 2020, 36 (6):  82-88.  DOI: 10.11924/j.issn.1000-6850.casb20190900649 Abstract + ( 470 )   HTML ( 1 )   PDF ( 1481KB )   ( 255 ) To reveal the genetic relationship among different mid-matured cotton germplasms, select parent materials for superior hybrid combinations, and finally obtain the target superior germplasms and approved varieties, the genetic diversity of 87 cotton varieties or lines was studied using SRAP markers. The polymorphic SRAP primers were selected from 80 pairs of primer combinations for PCR amplification among the test materials. The results showed that a total of 168 loci were detected using 17 pairs of polymorphic SRAP primers, 90 of which were polymorphic, with an average of 5.29 polymorphic loci per primer, and the polymorphic rate was 53.57%. Data analysis by NTSYS-pc2.11 software showed that the genetic similarity coefficient of 87 cotton materials ranged from 0.61 to 1.00, with an average of 0.82. When the genetic similarity coefficient was given as 0.73, 87 cotton materials could be clustered into two groups, of which the first group included 65 materials and the second group included 22 materials. The genetic diversity analysis suggests that the genetic basis of mid-matured cotton is relatively narrow, and the materials with distant genetic relationship should be selected as hybrid parents to create new mid-matured cotton germplasm resources in future.

  Structure Modification of Edible Fungi Polysaccharides and Their Antitumor Activities: A Review Zhou Yan, Zhang Cong, Zhao Dandan 2020, 36 (6):  89-92.  DOI: 10.11924/j.issn.1000-6850.casb19010147 Abstract + ( 520 )   HTML ( 5 )   PDF ( 1169KB )   ( 135 ) Edible fungus polysaccharide is a kind of important biomacromolecules with various bioactivities. Polysaccharide bioactivities have direct relationship with their structure. Thus, for modifying polysaccharide structure, the suitable modification way becomes an important direction for polysaccharide research. This study summarizes the modification ways of edible fungus polysaccharide and their antitumor activities, including sulfated modification, carboxymethylation modification, phosphorylation modification, acetylation modification and other chemical modifications of edible fungus polysaccharide. At last, the future research directions are pointed out, such as the other modification ways (except sulfated modification), the relationship between the modified polysaccharide structure and the pharmacological efficacy, and the other bioactivities of edible fungus polysaccharide.

  Applications of SPR Biosensing Technology in Agricultural Products Safety Detection Wang Tingting, Hu Jiandong 2020, 36 (6):  93-99.  DOI: 10.11924/j.issn.1000-6850.casb18110039 Abstract + ( 651 )   HTML ( 1 )   PDF ( 1509KB )   ( 88 ) Surface plasmon resonance (SPR) as a novel technology has advantages of small sample volumes, high sensitivity and fast detection speed, which is widely applied in environmental detection, medical diagnosis, drug screening, proteomics, genomics and many other fields. With its development, SPR is combined with biotechnology, then modified by specific antigen, antibody and signal amplification factor, and widely used in safety detection of agricultural products. The paper introduces the application of SPR in detection of pesticide and medicine residues, animal disease, microbe, food additives, heavy metal and transgenic test in agricultural products. The study could provide certain references for understanding the development status of SPR in food safety test.

  Status and Control Countermeasures of Major Wheat Aero-borne Diseases in Hebei Cao Qiao, Gao Zhenxian, Shan Zilong, Fu Xiaoyi, Shi Zhanliang, He Mingqi, Han Ran 2020, 36 (6):  100-105.  DOI: 10.11924/j.issn.1000-6850.casb18110040 Abstract + ( 716 )   HTML ( 1 )   PDF ( 1126KB )   ( 140 ) The occurrence and prevalence of wheat aero-borne diseases depend largely on climate conditions, and these diseases are unpredictable, spread quickly and difficult to control. The frequent aero-borne wheat diseases in Hebei mainly include rust, powdery mildew and fusarium head blight (FHB). The authors summarized the situation and harmful characteristics of the three diseases’ occurrence in Hebei, and discussed the major reasons of their outbreaks in the last decade. In addition, the authors reviewed the development in resistance breeding and biological control of the three diseases. Finally, the authors proposed control countermeasures to ensure the sustainable and high production of wheat in Hebei.

  Super Low Temperature Technology: Research Progress and Its Application Prospect in Sugarcane Detoxication Wu Yuanli, Zhang Shuzhen, Tan Xianjiao, Yang Benpeng 2020, 36 (6):  106-111.  DOI: 10.11924/j.issn.1000-6850.casb18100101 Abstract + ( 428 )   HTML ( 2 )   PDF ( 1106KB )   ( 654 ) Super-low temperature treatment is a new type of detoxification technology based on plant tissue culture and cryopreservation. To study its application prospect in detoxification of sugarcane, the authors analyzed the methods and detoxification efficiency of the treatment in common crops and the existing detoxification technology of sugarcane, summarized the principles, methods and detoxification effect of the treatment. This study could provide new ideas for sugarcane detoxification.

  Efficient Bactericides for Kiwifruit Canker: Screening and Field Application Evaluation Hu Rongping, Shi Jun, Lin Lijin, Yang Dongsheng, Ye Huili, Chen Cheng, Fan Zhonghan, Chen Song, Chen Qingdong 2020, 36 (6):  112-116.  DOI: 10.11924/j.issn.1000-6850.casb18100118 Abstract + ( 642 )   HTML ( 1 )   PDF ( 1241KB )   ( 74 ) The study aims to screen highly efficient bactericides against the kiwifruit canker and determine matching field application methods for disease prevention and control. The tube plate method was used to determine the virulence of 10 bactericides, single-factor random block design was used in field experiment, and water was taken as check. The results showed that four bactericides, 80% ethylicin, 0.15% tetramycin, 3% zhongshengmycin and 98% oxytetracycline, had better control efficacy with inhibition zone more than 40 mm, and the bacteriostasis rate was 70.49%, 70.49%, 68.85% and 65.57%, respectively. The transparency was above +++. 80% ethylicin had the best antibacterial effect with the indoor toxicity EC50 of 0.4978 mg/L. Field efficacy trials showed that 400 times diluted ethylicin had the best control efficiency of 68.77%. The best drug-delivery way was root-irrigation + trunk injection, the control efficiency reached 71.41%. 80% ethylicin and its matching application methods can provide a new way for preventing kiwifruit canker.

  3% Sigma Oil Suspension Concentrate Combined with 3% Fluperazine and Butachl Suspension Concentrate Controlling Weeds in Winter Wheat Field: Field Efficacy Evaluation Sun Bin, Wang Suping, Zhang Jiajia, Yu Siqin, Chen Gang 2020, 36 (6):  117-120.  DOI: 10.11924/j.issn.1000-6850.casb18110006 Abstract + ( 450 )   HTML ( 3 )   PDF ( 1149KB )   ( 108 ) The paper aims to effectively control the hazards of Triticum aestivum and 1-year-old broad-leaved weeds, and screen herbicides with good control efficacy. We conducted field trials on the control of weeds in winter wheat field by mixing 3% Sigma oil suspension concentrate and 3% Fluperazine and Butachl suspension concentrate. The results showed that: 30 d after spraying on wheat leaves at returning green stage, the control effect on Veronica didyma Tenore, Descurainia sophia (Linn.) Webb ex Prantl, Galium aparine Linn. var. tenerum Gren.et Godr. Rebb. and Capsella bursa-pastoris (L.) Medic. reached 50.0%-72.5%; 45 d after the treatment, the control effect on the fresh weight of Veronica didyma Tenore, Descurainia sophia (Linn.) Webb ex Prantl, Galium aparine Linn. var. tenerum Gren.et Godr. Rebb. and Capsella bursa-pastoris (L.) Medic. reached 67.2%-95.8%, and the control effect on the fresh quality of Aegilops tauschii Coss. was up to 81.3%. The results indicate that the mixture of 3% Sigma oil suspension concentrate and 3% Fluperazine and Butachl suspension concentrate could effectively control Aegilops tauschii Coss. and 1-year-old broad-leaved weeds, and could achieve the best weed control effect after wheat returning green, at the same time, the field investigation shows the mixture is safe for wheat.

  Efficacy of 22.4% Spirotetrama Suspension Against Bemisia Tabaci Xie Xianbiao, Xiao Wenxiang, Meng Jizhi, Yang Zuobin, Shen Yunfeng, Hu Chunliang 2020, 36 (6):  121-126.  DOI: 10.11924/j.issn.1000-6850.casb18110042 Abstract + ( 693 )   HTML ( 0 )   PDF ( 1210KB )   ( 75 ) We selected three kinds of insecticides, which were 22.4% Spirotetrama suspending agent, TTP200SC and Betwifruit (10% OD), and studied their effect on Bemisia Tabaci in tomato. The results showed that the drug effect increased in the first 1 to 7 days after application, and gradually decreased from 7 to 21 days, the drug effect could last for 21 days. When TTP + Spirotetrama were used as 199.5 mL + 417 mL, the drug effect was good after application for 1, 3, 7, 14 and 21 days, and the comprehensive control effect reached the best 7 days after the application, the effective rate was 93.06% and 92.19% for nymph and adult worm. The treatment has the best control effect and lasting effect on Bemisia Tabaci.

  Investigation on Pollinators and Flower-visiting Behavior of Dominant Pollinators of Pear Trees in Different Eco-regions Guo Yuan, Wu Wenqing, Zhang Xufeng, Zhang Yunyi, Song Huailei 2020, 36 (6):  127-131.  DOI: 10.11924/j.issn.1000-6850.casb20190900643 Abstract + ( 619 )   HTML ( 4 )   PDF ( 1227KB )   ( 127 ) To explore the dominant pollinators of pear trees, we investigated the wild pollinators of pear trees in the plain and mountainous areas in Shanxi, and analyzed the species, quantity and flower-visiting behavior of the wild pollinators. The results showed that there were 4 orders, 15 families and 22 species in the two different eco-regions. The species and quantities of pollinators in the mountainous areas were more abundant than those in plain areas. Apis cerana cerana, Anthophora plumipes and Andrena thoracica were the dominant pollinators. All the three bee species visited upper middle flowers of the trunk frequently, the proportion of the upper flowers, middle flowers and lower flowers visited by Apis cerana cerana was 36.9%, 51.1%, 12.0%, respectively; by Anthophora plumipes was 46.5%, 38.0%, 15.5%, respectively, and by Andrena thoracica was 41.2%, 37.6%, 21.2%, respectively. The visiting frequency of Apis cerana cerana and Anthophora plumipes was (11.95±0.87) flowers/min and (12.52±2.16) flowers/min, respectively, which was significantly higher than (6.64±0.56) flowers/min of Andrena thoracica, so Apis cerana cerana was the ideal pollinators for pear trees. The research provides a theoretical basis for clarifying the current situation of pear tree pollinators in Shanxi and establishing a database of wild pollinators and pear tree pollination bees.

  Wheat Import Trade Pattern and Its Influencing Factors in China: Based on the Trade Gravity Model Li Haoran, Mu Yueying 2020, 36 (6):  132-139.  DOI: 10.11924/j.issn.1000-6850.casb20190900624 Abstract + ( 702 )   HTML ( 5 )   PDF ( 1273KB )   ( 276 ) China is a net importer of wheat and has a high dependence on the international market. Therefore, studying the source structure of China’s wheat import and its influencing factors are vital to China’s food security. Based on the analysis of wheat trade situation during 1992-2017, we studied the influencing factors of wheat import trade by using the gravity model. The results show that: since 2013, China’s wheat trade volume has been in a stable state, gradually forming an import pattern dominated by Australia, supplemented by the United States, Canada and Kazakhstan; China’s wheat import structure has been optimized, and the growth rate of wheat trade with countries such as Kazakhstan, Israel and other participating countries of the Belt and Road Initiative have been relatively high; moreover, geographical distance, coastal status, whether to join APEC, exporting country’s GDP of the year and its grain output in the last year significantly affect China’s wheat imports; finally, we also put forward some relevant suggestions.

  Production Efficiency and Its Influence Factors of Crop Planting Patterns in Chengdu Plain—A Case Study of Pidu District Wang Bin, Huang Shengyi, Min Qingwen, Yang Wanquan, Li Heyao, Zhang Bitian 2020, 36 (6):  140-148.  DOI: 10.11924/j.issn.1000-6850.casb18100079 Abstract + ( 397 )   HTML ( 0 )   PDF ( 1311KB )   ( 283 ) To study the farmland production efficiency of different planting patterns in Chengdu Plain, based on the survey data of 92 households in 13 towns of Pidu District, Chengdu City in 2017, the DEA-Tobit model was used to analyze the farmland production efficiency and the influence factors of the paddy-upland rotation and dry farming patterns in Pidu District. The results showed that the average farmland production efficiency of different planting patterns was 0.793. The order of the farmland production efficiency of different patterns was vegetable succession cropping or crop rotation (0.957), rice-garlic crop rotation (0.847), rice-rape crop rotation (0.782), succession cropping of leeks (0.759), rice-vegetable crop rotation (0.722) and rice-round root radish crop rotation (0.689). The reason why farmland production efficiency did not reach valid value 1 was mainly owing to lower scale efficiency. At the same time, the redundancies of capital and labor input were existed in all the patterns, and the output of rice-vegetable crop rotation and rice-rape crop rotation patterns were insufficient. The factors affecting the farmland production efficiency were different, and the policy factor had a relatively large effect on the efficiency. In order to further improve the farmland production efficiency in Pidu District, it is recommended to appropriately promote the large-scale operation of farmland, strengthen the transfer of surplus rural labor and improve various agricultural policy measures.

  Farmland in Guangdong: Marginalization Characteristics and Geographical Detection of the Influencing Factors Zeng Xiaojie, Wang Fang, Feng Yanfen, Zhu Shu 2020, 36 (6):  149-156.  DOI: 10.11924/j.issn.1000-6850.casb18100090 Abstract + ( 554 )   HTML ( 1 )   PDF ( 1297KB )   ( 87 ) To clarify the marginalization of farmland in Guangdong which is a developed area and its main influencing factors, using three major diagnostic indicators of “unit cost net income index”, “agricultural land use intensity index” and “agricultural crop planting area index”, we summarized the marginalization characteristics of farmland in Guangdong from 2000 to 2015, selected 19 factors affecting the marginalization characteristics of farmland, and explored the core influencing factors of farmland marginalization by geo-detector method. The results showed that: there were 3 obvious farmland marginalization in Guangdong from 2000 to 2015, appeared in 2001-2002, 2005-2006 and 2010-2013, respectively, and the third marginalization lasted for the longest time and was the most serious; the level of social and economic development and structural indicators and the indicators of changes in the structure of rural household resource elements had a great impact on the marginalization of farmland, among them, the proportion of tertiary industry value, the fixed assets investment of rural farmers, and the total planting area of grain had a strong explanatory power to the marginalization of farmland, q was 0.8067, 0.8055, 0.7916, respectively. Any interaction between the two factors can enhance the explanatory power of the marginalization of farmland.

  Rotation Mode of Traditional Agriculture in Pixian, Sichuan: Sustainability Evaluation Based on Input Output Model Li Shuwu, Yang Liyun, Chen Guoliang, Li Yuan, Min Qingwen, Yang Wanquan 2020, 36 (6):  157-164.  DOI: 10.11924/j.issn.1000-6850.casb18110036 Abstract + ( 598 )   HTML ( 3 )   PDF ( 1276KB )   ( 124 ) To explain the sustainability of the rotation mode in Pixian, Sichuan and its potential economic and environmental value, based on the theory of input-output, we built the value input-output table and the input-output coefficient table of 5 typical traditional rotation modes. Through the comparison between the traditional rotation mode and the modern continuous cropping mode, and the comparison between the traditional modes, we intuitively analyzed and evaluated the sustainability of the current rotation mode in Pixian. The results showed that: the dependency of the traditional rotation on pesticides and fertilizers was much lower than that of modern continuous cropping modes, and the biodiversity of crops was kept better because the traditional rotation mode conformed to the natural growth law of crops, but the output per unit area was lower than that of the continuous cropping mode. Input-output analysis of 5 traditional rotation modes of rice-garlic, rice-leek, rice-greens, rice-radish and rice-ginger found that: the input and output of the individual products were almost the same in 5 modes, indicating that this flood and drought rotation mode was an organic whole, unified and coordinated. In order to promote and inherit the traditional rotation mode, Pixian should build a good brand of organic green agricultural products in unique water source, the government should give corresponding encouragement and support in relevant policies.