Current issue

• 2020 Vol.36 No.11 Published:15 April 2020

  Effect of Nitrogen Levels on Oxidase Activities in Leaves and Roots of Winter Wheat Zhao Ruohan, Chen Hongwei, Ou Xingqi, Liu Jinjin, Jia Gai, Yao Sumei, Liu Mingjiu, Huang Ling 2020, 36 (11):  1-7.  DOI: 10.11924/j.issn.1000-6850.casb18120051 Abstract + ( 422 )   HTML ( 4 )   PDF ( 1330KB )   ( 89 ) To study the effects of nitrogen application on the metabolic difference of active oxygen in leaves and roots of winter wheat, ‘Bainong207’ was used as material, a rhizobox experiment was conducted with seven nitrogen application levels (N0-no nitrogen application, N1-120 kg/hm 2, N2-150 kg/hm 2, N3-180 kg/hm 2, N4-240 kg/hm 2, N5-270 kg/hm 2, N6-300 kg/hm 2). The relationships between malondialdehyde (MDA), soluble protein (WSP), total antioxidant capacity (T-AOC), superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) in leaves and roots of winter wheat at the early growth stage and the characteristics of roots growth were analyzed. The results showed that at the early growth stage, MDA contents in leaves and roots were the highest under low nitrogen levels. With the increase of nitrogen level in certain range, WSP in leaves and roots was the highest with N2 treatment. T-AOC was up to the highest level in N6 treatment. Roots were more sensitive to environment stress than leaves. Nitrogen improved the root activity, reduced the root cap ratio, and increased the leaf and root biomass. MDA contents in roots and leaves and APX activity in roots decreased with the increasing nitrogen fertilizer. T-AOC in roots and leaves, CAT activity in leaves and SOD activity in roots increased with the increasing nitrogen fertilizer. These results demonstrated that enzymatic reaction mechanism of root and leaf was independent and collaborative with different nitrogen amounts. The inhibition of high nitrogen on an antioxidant system influenced partially the activity of antioxidase. The comparatively optimal condition for antioxidase activity is medium nitrogen (150-240 kg/hm 2nitrogen application), which is beneficial to the growth and development of winter wheat at earlier stage and accords with the principle of decreasing fertilizer and enhancing efficacy.

  Xinjiang Wheat Varieties: HMW-GS Expression and the Correlation Between HMW-GS Expression and Quality Characters Cao Junmei, Zhang Xinzhong, Fan Guiqiang, Lu Jing, Wu Xinyuan, Zhou Anding, Liu Lianzheng, Nie Shihui 2020, 36 (11):  8-14.  DOI: 10.11924/j.issn.1000-6850.casb19030014 Abstract + ( 369 )   HTML ( 1 )   PDF ( 1253KB )   ( 63 ) To provide a basis for determining the optimum ecological areas of high-quality wheat varieties, 7 Xinjiang major wheat varieties with three types of gluten were planted on five typical ecological areas. The composition, expression of high-molecular-weight glutenin subunit (HMW-GS) and main quality characters were analyzed. The results showed that, there were 10 subunits and 6 subunit combinations in the tested materials; the HMW-GS expression differences among the varieties were significant or extremely significant, but they were different among different ecological areas. In terms of subunit types, the variation range of 2* subunit expression was the largest, and the variation range of 12 subunit expression was the smallest. As far as the ecological areas were concerned, HMW-GS expression of Qitai had the biggest variation, while that of Tacheng was relatively stable. The formation time, stabilization time and evaluation value affected by the ecological areas had obvious variation, and the variation of bulk density and water absorption were not obvious. The correlation of expression levels of 2*, 5, 8 and 9 subunits with the main quality traits were high, while 1, 2, 7, 10 and 12 subunits were not significantly correlated with the main quality traits. In conclusion, the ecological types of Xinjiang are complex and diverse, and the expression range of wheat glutenin subunits has a wide distribution, wheat varieties with different quality types should be planted according to the expression level of subunit to explore their quality potential.

  Growth Inhibitors of Different Concentrations: Effect on Economic Characters and Yield of Direct-Harvesting Summer Maize Chen Jun, Zhang Haijun, Han Mingming 2020, 36 (11):  15-19.  DOI: 10.11924/j.issn.1000-6850.casb19020079 Abstract + ( 317 )   HTML ( 4 )   PDF ( 1246KB )   ( 184 ) The aim of the experiment is to obtain the suitable concentration of a growth inhibitor for improving the quality and yield of direct-harvesting summer maize ‘Dika 517’. The standard solvent was 1.0 mL/kg 30% diethylaminoethyl hexanoate and ethephon mixture (DHE) water agent (100%). According to 6 concentration ratios of 25%, 50%, 75%, 100%, 150%, and 200%, it was titrated into 6 spray watering pots with the same volume by the test tube, and the control treatment was water. The reagent was fully dissolved and the foliar spray was carried out corresponding to the experimental treatment. Results showed that 50% concentration treatment decreased the height of the maize plant by 23 cm, and reduced the height of ear by 5 cm, which enhanced the performance of lodging compared with the control treatment. In addition, the grain weight per ear was significantly higher than that of the control and 100% as well as above 100% treatments, which suggested that the quality of the grain of 50% concentration treatment was better than that of the control. Although the 100-grain weight of 50% treatment was only less than 75% treatment, the seed rate of 50% treatment was the highest in all the treatments. The plot yield of 50% treatment had obvious difference with that of the control. 0.50 mL/kg ‘30% DHE’ decreased the plant height and ear height reasonably, and increased the yield and quality. Therefore, it is recommended to be used in ‘Dika 517’ production under the planting density of 8.25×10 4 plant/hm 2.

  Automatic Identification of Elaeagnus L. Based on Leaf Digital Texture Feature Wang Leihong, Cheng Yongsheng, Zheng Yuhong 2020, 36 (11):  20-25.  DOI: 10.11924/j.issn.1000-6850.casb18110086 Abstract + ( 436 )   HTML ( 1 )   PDF ( 1256KB )   ( 98 ) This study aims to explore the variation pattern of leaf digital texture feature of Elaeagnus L.. The leaf texture parameters were extracted based on Gray-level co-occurrence matrix from the eight species of Elaeagnus L. from Zhejiang, Jiangsu, and Anhui Province. The variation pattern of leaf texture parameters was analyzed within and among species. KNN classification model was established. The results showed that all texture parameters of the same species from different geographical sources had highly significant differences, while only one texture parameter had significant difference between different species. The KNN classification recognition model was constructed by 132 random samples as train data, 35 random samples as test data. The correct recognition rate of this model was 93.75% at K=6. The leaf digital texture has the significance of classification recognition to some species of Elaeagnus L. in a certain distribution range, and it can be used to construct k-nearest neighbor classification model.

  Genomic DNA of Pilose Antler: Comparison of Extraction Methods Yang Chonghui, Zhao Daqing, Song Wenbo, Yin Chengcheng, He Huinan, Wang Xiuge, Li Fangyu, Yang Yang, Jing Li, Qi Bin 2020, 36 (11):  26-32.  DOI: 10.11924/j.issn.1000-6850.casb20191100790 Abstract + ( 397 )   HTML ( 1 )   PDF ( 1951KB )   ( 108 ) The objectives are to establish a stable and efficient method for extracting DNA from pilose antler and meet the needs of DNA barcode identification methods for pilose antler in the future. The genomic DNAs from 8 batches of velvet medicinal materials from 5 manufacturers on the market were extracted by two kinds of kits, modified CTAB method and SDS method. The three factors of sample size, water bath temperature and action time were investigated by referring to 9107 from the General Principles of Pharmacopoeia of the People's Republic of China (Ⅳ, 2015). The results showed that all methods could extract genomic DNAs from pilose antler. TIANamp Genomic DNA Kit got the best extraction, while the modified CTAB method had worse extraction. By methodological study, TIANamp Genomic DNA Kit had the best extraction with the extraction condition of the sample quantity for 70 mg, and the water bath temperature 56℃ for 6 h. TIANamp Genomic DNA Kit screened in this study can use simple and convenient method to extract and obtain excellent concentration and quality DNA, so it can be used for subsequent identification of DNA barcode in the future.

  miR398 Family in Plants: Molecular Characteristics and Evolution Analysis Gao Fan, He Zhongshi, Song Wei, Xu Lu, Zhao Jia 2020, 36 (11):  33-42.  DOI: 10.11924/j.issn.1000-6850.casb20191100810 Abstract + ( 681 )   HTML ( 9 )   PDF ( 2018KB )   ( 265 ) miR398 family is a class of conserved miRNA family in plants. This paper aims to explore the molecular characteristics of plant miR398 family members and interpret their phylogenetic patterns. The matures, precursors and targeted sequences of miR398 family in plants reported in the database were used as the test data. Their molecular characteristics and phylogenetic patterns were analyzed by statistical and bioinformatics methods. MiR398 family members are widely distributed among 34 plant species, and their matures length, nucleotides types, precursors structures, and targeted genes inhibition types are all conformed to typical plant miRNA molecular characteristics. Moreover, the sequences of miR398 matures are more conservative than the precursors, and their stem structures are more conservative than the loop ones. It is found that the miR398 family members in the same plant species have different evolution rates. Additionally, miR398 family among a few plant species has coevolution characteristics. The functional prediction results of miR398 target genes show that miR398 family members are widely involved in plant stress response process via cleaving inhibition. The miR398 family in plants has conservative and polymorphic molecular characteristics, and the miR398 family in different plants has diverse evolutionary patterns. This study can provide certain theoretical references for exploring the mechanism of miR398-mediated stress response in plants.

  Fertilization System of Nutrient Critical Value for Optimum Yield of Tobacco in Yuxi Chen Jianfeng, Chen Hua, Yin Mei, Wang Zhiyuan, Hong Lifang, Su Fan, Li Guohong, Fu Libo 2020, 36 (11):  43-48.  DOI: 10.11924/j.issn.1000-6850.casb18120083 Abstract + ( 378 )   HTML ( 2 )   PDF ( 1247KB )   ( 93 ) The paper aims to study the targeted fertilizing method of tobacco in Yuxi. A field experiment with tobacco ‘K326’ was conducted in Yuxi to investigate the relationship of the amount of fertilizer applied at current season, soil nutrients data obtained in soil testing, and the tobacco yield and net output. It was found that the tobacco yield, average price, net output and tobacco leaf qualities were all the highest in N2P2K2 treatment plots (local recommended fertilizer amount) in each experiment site. Under the fertilizer-lacking experiments carried out on different sites, the correlations of soil nutrients (alkaline hydrolyze nitrogen, available phosphorus and available potassium) with tobacco yield were significantly positive. The regression equation between soil nutrient contents and soil nutrient correlation coefficient could be expressed as follows: yN=0.3246-0.04lnxN, yP=0.7061-0.116lnxP, yK=0.6244-0.089lnxK (yN, yP and yK was the effective coefficient of soil nitrogen, phosphorus and potassium respectively; xN, xP and xK was the content of soil alkali-hydrolyzed nitrogen, available phosphorus and available potassium respectively). The nutrient critical value for the optimum yield of high quality ‘K326’ was calculated according to the economic optimum application rate and the levels of available nutrients in soil. To achieve the yield of more than 2700 kg/hm 2, the nutrient critical values of high quality ‘K326’ planted in the paddy soil at the elevation of 1500-1800 m could be calculated as follows: N was (161.955±18.345) kg/hm 2; P2O5 was (77.610±12.12) kg/hm 2; K2O was (349.95±45.675) kg/hm 2. To achieve the yield of more than 2250 kg/hm 2, the nutrient critical values of high quality ‘K326’ planted in the red soil at the elevation of 1500-2000 m could be calculated as follows: N was (138.945±30.705) kg/hm 2; P2O5 was (65.295±17.34) kg/hm 2; K2O was (306.48±49.905) kg/hm 2.

  The Development and Application of SSR Markers Linked to Male Sterility Restoration Site Ms Locus in Allium cepa L. Yang Yahui, Liu Bingjiang, Yang Yanyan, Wu Xiong, Cao Chenxing, Huo Yumeng 2020, 36 (11):  49-55.  DOI: 10.11924/j.issn.1000-6850.casb18120064 Abstract + ( 622 )   HTML ( 1 )   PDF ( 1937KB )   ( 58 ) This study aims to develop a stable and reliable molecular marker of onion fertility locus and apply it to breeding practice for screening breeding lines, which will further shorten the breeding cycle, save breeding costs, and accelerate the cultivation process of onion hybrids. Based on the AFLP sequences of onion fertility restoration Ms locus, WH-SSR-1 molecular marker was developed, identified and applied in breeding practice by sequence alignment analysis, PCR detection and phenotype analysis. The results showed that WH-SSR-1 marker was closely linked to Ms locus. When Ms locus genotype was homozygous dominant MsMs, there was one 102 bp band; when Ms locus genotype was homozygous recessive msms, there was only one 99 bp band; when Ms locus genotype was hybridized Msms, there were two bands, 102 bp band and 99 bp band, respectively. The validation results of 32 onion materials confirmed that the marker type of Ms locus was completely consistent with the genotype. Subsequently, two matching maintainer and sterile lines were directly developed from four OP populations, but ‘Diaoyu’ and ‘Tianzhenghongyu’ could not be easily matched because no maintainer or sterile individuals were detected. The WH-SSR-1 marker is closely linked to Ms locus and can be used in the breeding practice. The maintainer and sterile individuals can be directly selected from OP population, and can be matched with each other and form counterpart breeding lines at the same time.

  Cymbidium mosaic virus and Odontoglossum ringspot virus: Research Progress on Detection Techniques and Virus Elimination Wang Renrui, Li Jie 2020, 36 (11):  56-62.  DOI: 10.11924/j.issn.1000-6850.casb18120069 Abstract + ( 539 )   HTML ( 3 )   PDF ( 1262KB )   ( 118 ) To clarify the research development of detection techniques and virus elimination methods of Cymbidium mosaic virus (CymMV) and Odontoglossum ringspot virus (ORSV), we summarized the detection and elimination methods of the two viruses and the virus elimination efficiency, analyzed the defects of traditional virus-free methods, and pointed out that the traditional virus-free methods could not meet the demand of orchid virus elimination research. Based on the analysis, a new safe and reliable virus-free method is proposed to solve the bottleneck of orchid industry. Cryotherapy, which has many advantages compared with the traditional methods, has been proven to be a new technique for plant pathogen elimination with successful application on several plants, and can provide a technical support to CymMV and ORSV elimination.

  Fine Roots in Northern Forests: Response to Atmospheric N Deposition Increase and Temperature Rise Ding Lizhi, Xing Yajuan, Yan Guoyong, Wang Qinggui 2020, 36 (11):  63-73.  DOI: 10.11924/j.issn.1000-6850.casb18120133 Abstract + ( 410 )   HTML ( 3 )   PDF ( 2065KB )   ( 73 ) Under the background of increasing atmospheric N deposition and rising temperature, the potential changes of production and physiology and ecology of fine root will affect nutrient supply and terrestrial C cycle in forest soil. Based on 170 sets of data from 34 published papers on N deposition, temperature rise and their interaction in northern forests, we studied the responses of fine roots to warming, increasing N and their interaction by meta analysis. The results showed that: (1) increasing N significantly inhibited the biomass of fine roots and increased the content of C and N in fine roots, while decreased P significantly, the respiration rate of fine roots increased significantly, and the morphology of fine roots became slender; (2) warming significantly increased the availability of soil C, the biomass, tissue density, N uptake rate, tissue N concentration and respiration of fine roots, but the content of C and N, specific root length, diameter and respiration rate of fine roots decreased with the increase of temperature; (3) under the interaction of rising temperature and increasing N, the biomass, respiration rate and the content of C, N of fine roots increased significantly except the inhibition of tissue N concentration. The results show that the rising temperature and increasing N significantly affect the biomass, turnover, nutrient content and morphological characteristics of fine roots in northern forests, and could provide reference and data support for improving and perfecting the C budget model.

  The Impact of Land Use Change on Ecosystem Service Value in Baiyin Wu Cuixia, Feng Yongzhong, Tao Zhuolin, Qiu Xiaoyi, Mao Long, Lei Yuanqi 2020, 36 (11):  74-81.  DOI: 10.11924/j.issn.1000-6850.casb20191000760 Abstract + ( 406 )   HTML ( 1 )   PDF ( 1445KB )   ( 171 ) To clarify the relationship between land use status and ecosystem service value in Baiyin City, and further determine the impact of land use types on the ecosystem, in the study, the equivalent factor method was used to evaluate the land use status, ecosystem service value and the relationship between them in Baiyin City from 2009 to 2017. The results showed that: (1) from 2009 to 2017, the total value of ecosystem services decreased from 5.675 billion yuan to 5.649 billion yuan in Baiyin City, the general trend was downward, all ecosystem functions and ecosystem services were also downward; the value of grassland ecosystem services had the largest reduction and decreased by 25.4918 million yuan, and the population load on the ecosystem showed a downward trend; (2) land use types had great impacts on ecosystem service value in Baiyin City, it was mainly due to the increase of construction land and the decrease of grassland and woodland area. In future development, we should explore the ecological development from the aspects of protecting ecological land and excavating the stock of construction land.

  Boron Magnesium Calcium Soil Conditioner: Effects on Acidified Soil Inhibition in Red Soil Dry Land Hu Dandan, Wang Huiming, Wu Changqiang, Hu Qiuping, Song Huijie, Liu Jinyou, Hu Huiwen 2020, 36 (11):  82-85.  DOI: 10.11924/j.issn.1000-6850.casb20191100811 Abstract + ( 394 )   HTML ( 2 )   PDF ( 1262KB )   ( 89 ) Aiming at the problem of acidified red soil dry land in southern China, the paper aims to provide technical support for the application and promotion of boron magnesium calcium soil conditioner on the red soil. Taking sweet potato as the main crop, we compared the application of boron magnesium calcium soil conditioner with 750 kg/hm 2 (T50), 1500 kg/hm 2 (T100) and 2250 kg/hm 2 (T150) and conventional fertilization (CK) by field test to study the effect on sweet potato yield in red soil dry land in Jiangxi and the acidified soil inhibition. The results showed that: compared with CK, the application of boron magnesium calcium soil conditioner for two consecutive years could increase the sweet potato yield by 22.45%-78.40%, the soil pH by 0.13-0.30 units, and the total amount of soil exchangeable acid decreased by 0.07-0.28 cmol/kg, overall, the improvement effect was better with the increase of the amount of boron magnesium calcium soil conditioner. There was no clear influence on the alkali nitrogen content of soil, and the effect on soil organic matter, available phosphorus and available potassium was not significant. In general, the application of boron magnesium calcium soil conditioner in red soil dry land can significantly increase the sweet potato yield, and also play a role in increasing soil pH and activating soil phosphorus and potassium and so on.

  Hyperspectral Indirect Estimation Model of Soil Water Content in Cultivated Layer Zhai Haoran, Li Xican, Zhong Hao, Zhou Yu 2020, 36 (11):  86-91.  DOI: 10.11924/j.issn.1000-6850.casb18120093 Abstract + ( 329 )   HTML ( 3 )   PDF ( 1621KB )   ( 89 ) The objectives are to overcome the limitation that optical satellite remote sensing can only obtain the surface soil spectral information and can not be used to directly estimate the soil water content of the cultivated layer, and establish an indirect estimation model of the cultivated layer soil water content based on the surface soil spectral information. According to the soil water content and hyperspectral data of 85 tidal soil samples in Jiyang, Shandong, and the intrinsic relationship between the soil water content of the surface layer and the cultivated layer, an indirect spectral estimation model of soil water in the cultivated layer was established. The results showed that the logarithmic transformation effect of spectral reflectance of surface soil was better. With the logarithmic transformation values of 1339 nm, 1457 nm, 1745 nm, 1969 nm and 1996 nm bands as estimation factors, the determinant coefficient R 2 of the surface water content estimation model established by multiple linear regression model was 0.8911 and the average relative error was 13.67%. There was a significant correlation in soil moisture content between the surface layer and the cultivated layer, and the determinant coefficient R 2 between them was 0.8131. The accuracy of the indirect spectrum estimation model of soil water content in the cultivated layer was higher, the model’s determinant coefficient R 2 was 0.8138 and the average relative error was 9.66%. The results indicate that there is a significant correlation between the surface and the cultivated soil water content of the tidal soil in Jiyang, Shandong, and it is feasible and effective to estimate the soil water content of the cultivated layer by using the surface soil spectrum.

  Optimizing the Determination Conditions of Total Bacterial Colonies in Soil Xie Xia, Yang Jianlan, Liu Xinyu 2020, 36 (11):  92-95.  DOI: 10.11924/j.issn.1000-6850.casb20191200977 Abstract + ( 1035 )   HTML ( 6 )   PDF ( 1257KB )   ( 230 ) The colony counting is a common method for measuring the total number of culturable microorganisms in soil, but with poor repeatability. We studied the effects of culture time, inoculation method, sample particle size, number of glass beads and type of medium on the colony counting results during the experiment. The results showed that the counting number was gradually stabilized after the fourth day of culture; the total number of colonies obtained by the spread inoculation was higher, which was 3.11 times that of the pour inoculation; the maximum total number of colonies was measured when the soil particle size was 50 mesh. The maximum number of colonies could be obtained by preparing the soil extract with 40 glass beads. The total number of colonies on SOC medium was 1.07×10 7 CFU/g, which was 1.28 times, 2.32 times and 1.63 times that of the LB medium, TB medium and heterotrophic bacteria medium, respectively.

  Comparative Study on Fecal Disposal Capacity of Different Heterotopic Fermentation Mattresses Yin Xiaodong, Zhao He, Gao Fei, Li Huixin, Jiao Jiaguo, Lin Yaopeng, Bi Wen, Chen Chungen 2020, 36 (11):  96-101.  DOI: 10.11924/j.issn.1000-6850.casb18120073 Abstract + ( 540 )   HTML ( 4 )   PDF ( 1397KB )   ( 181 ) To compare the absorption capacity of pig manure with different bedding materials, in this experiment, based on the technology of microbial heterotopic fermentation bed, the difference of fermentation technology, physicochemical properties of fermentation products and the ability to absorb feces between sawdust and rice husk were compared and analyzed. The results showed that under the condition of bedding moisture content of 70%, all the beddings could ferment normally. The temperature of bedding material increased first and then decreased, and the high temperature period above 55℃ of each cushion maintained for more than 20 days, the highest temperature of rice husk cushion reached 69.5℃. The pH value in the fermentation process of bedding material was weak alkaline, with the increase of fermentation time, the organic carbon content of different bedding materials did not change much, but the nitrogen content decreased continuously, and the phosphorus and potassium content increased. The sawdust cushion was more suitable as a bedding material for fermentation bed than rice husk, since its pig manure absorption capacity was twice of that of rice husk cushion,.

  Early Rice: Relationship Between Sowing Date and Heat Utilization Efficiency Zeng Kai, Yao Junmeng, Cao Heyu, Hu Lei, Zhang Chonghua, Wang Shangming, Zhang Qingxia, Wang Chengzi 2020, 36 (11):  102-107.  DOI: 10.11924/j.issn.1000-6850.casb20190600339 Abstract + ( 382 )   HTML ( 1 )   PDF ( 1384KB )   ( 86 ) To prevent the blind extension of sowing date, the research was conducted through field sowing test at different stages and the analysis of heat distribution, combined with the study on the developmental period and the biological factors. The results showed that: although the early sowing early rice once reached the highest tillering rate, suitable sowing early rice still achieved the highest effective stem multiple at the harvest time; the total maximum biomass was obtained by early sowing, and the ideal yield was obtained by suitable sowing; early sowing early rice had more non-effective tillers; the suitable sowing hold an advantage in yield structure; late sowing early rice did not perform well on the number of panicles and single-earned panicles; early sowing early rice had high management cost and showed a high probability of suffering low temperature at seedling stage and heavy rain during the flowering period; late sowing early rice was easy to suffer from extreme heat at heading and filling stage, which had adverse effects on chlorophyll, photosynthesis and rice quality. To extend the sowing date, the risk caused by climate change and its repetitiveness, and the different effects of heat distribution on the biomass and yield should be considered comprehensively.

  Canonical Correlation Analysis between Body Weight and Adult Traits in Yunshang Black Goat Tao Lin, Yang Hongyuan, Jiang Yanting, He Xiaoyun, Hong Qionghua, Chu Mingxing 2020, 36 (11):  108-112.  DOI: 10.11924/j.issn.1000-6850.casb20190500112 Abstract + ( 571 )   HTML ( 4 )   PDF ( 1226KB )   ( 328 ) To explore the relationship between body weight and adult traits of Yunshang black goat, based on the body weight and adult traits data of 98 Yunshang black female goats, Pearson correlation analysis and canonical correlation analysis were performed on 11 variables using R software. The results of Pearson correlation analysis showed that there was a highly significant correlation between adjacent body weight (0.30<r<0.42, P<0.01) except adjusted body weight at 12 and 18 months of age; there was a highly significant correlation between adjusted body weight at 18 months of age and adult traits except body height (0.39<r<0.76, P<0.01); chest girth, canal circumference, backfat thickness and eye muscle area were significantly correlated (0.24<r<0.76, P<0.05). Canonical correlation analysis showed that the correlation between body weight and adult traits was mainly contributed by adjusted body weight at 18 months of age and chest girth. The study indicates that chest girth could be selected as a promising breeding index which is a key adult trait affecting body weight of Yunshang black goat.

  Mulberry Leaf Powder: Effects on Growth Performance and Organ Development of 1-28 Day Age of ‘Frizzle’ Broilers Li Haiwei, Li Yingjia, Rong Sihua, Wu Gengxuan, Zhang Jinhua, Zhang Lianzheng, Zhu Siqi, Huang Xiaoliang, Huang Guanqing 2020, 36 (11):  113-117.  DOI: 10.11924/j.issn.1000-6850.casb20190500118 Abstract + ( 417 )   HTML ( 3 )   PDF ( 1320KB )   ( 150 ) This study is to determine the effect of mulberry leaf powder on growth performance and organ development of ‘Frizzle’ broiler. A total of 144 one-day-old female ‘Frizzle’ broilers were allocated to 4 groups with 6 replications (6 ‘Frizzle’ broilers/pen). 4 groups were set up: A group (basal diet), B group (A + 1.0% mulberry leaf powder), C group (A + 3.0% mulberry leaf powder), D group (A + 5.0% mulberry leaf powder). The experiment lasted for 28 days. The results showed that: dietary mulberry leaf powder supplementation decreased average daily gain (ADG) and increased the feed conversion ratio of ‘Frizzle’ broiler. Dietary 3.0% mulberry leaf powder supplementation increased feed conversion ratio significantly (P<0.05). Dietary 5.0% mulberry leaf powder supplementation decreased ADG significantly (P<0.05). No difference (P>0.05) was observed in the average daily feed intake, absolute organ weight, and relative organ index. Dietary mulberry leaf powder supplementation could improve the intestinal length and relative index to some extent, but not significantly (P>0.05). In view of the ‘Frizzle’ broilers’ growth performance, it is not necessary to supplement much dietary mulberry leaf powder in the daily ration of ‘Frizzle’ broilers from1-28 days of age.

  Winter Wheat Planting Information Extraction in Qingdao: Based on High-resolution Satellite Imagery Liu Xuegang, Li Feng, Guo Lina 2020, 36 (11):  118-123.  DOI: 10.11924/j.issn.1000-6850.casb19010091 Abstract + ( 547 )   HTML ( 7 )   PDF ( 2052KB )   ( 409 ) To accurately obtain the planting information of winter wheat, which is the main crop in Qingdao, taking the GF-1/16 m satellite imagery as the main data source, combined with the auxiliary data source including the elevation, land utilization and field survey data, we calculated and got the results that the optimum time phase for extracting the remote sensing area of winter wheat in Qingdao was April through the spectral differences between the main development period of winter wheat and other features on the satellite imagery of GF-1/16 m. During its optimum time phase in 2017, we extracted the planting area and distribution area of winter wheat in Qingdao by the decision tree classification and districting interpretation. Besides, the 1 m satellite imagery fused GF-2, ground survey data and the data released by the statistics agency were adopted to verify the accuracy of the classification results. The results showed that: the remote sensing estimation method for winter wheat planting area on regional scale was feasible by using the advantages of GF-1/16 m satellite imagery in width, time and spatial resolution to introduce land utilization and elevation into the decision tree classification model. By verification of accuracy, the total accuracy of remote sensing interpretation for winter wheat in Qingdao in 2017 was 94.3%, and the Kappa coefficient was 0.857. The remote sensing extraction area was slightly smaller than the data released by the statistics agency, and the extraction accuracy of total area was 93.6%. This study provides reference for the extraction of crops planting area on regional scale based on high-resolution satellite imagery.

  Age and Growth of Hypophthalmichthys molitrix in the Middle of the Minjiang River Wang Maoyuan 2020, 36 (11):  124-129.  DOI: 10.11924/j.issn.1000-6850.casb19010109 Abstract + ( 634 )   HTML ( 3 )   PDF ( 1411KB )   ( 309 ) To reveal the age and growth of silver carp (Hypophthalmichthys molitrix) in the middle of the Minjiang River, 126 specimens were collected from June 2015 to March 2017 in the middle of the Minjiang River, the scale rings’ observation and basic biology measurement were conducted to determine the age and growth characteristics. The results showed that the body weight of the silver carp ranged from 310.6 to 9420.8 g, and the body length ranged from 23.4 to 86.9 cm. The scale rings were closed cutting type and had sparse and dense characteristics. The age of the individuals ranged from 1 + to 7 +, and most of the individuals aged 3 + to 4 +. The obvious power function relationship between body length (L) and body weight (W) could be expressed as W=0.027×L 2.953, power exponent approached 3. The silver carp in the middle of the Minjiang River was of the uniform growth type, and its growth could be described by the Von Bertalanfly growth equations: Lt=106.696×[1-e -0.147( t +1.1443)], Wt=26332.083×[1-e -0.147( t +1.1443)] 2.953. The growth inflection ti=5.923. Compared with silver carps in other water, its growth performance was slightly lower. Therefore, the fist capture of silver carp in the middle of the Minjiang River should be greater than 70 cm length and 7.7 kg weight. At the same time, we should regulate fishing gear and fishing methods to reduce fishing intensity and increase resource conservation efforts, so as to promote the recovery and protection of the silver carp resources in the Mingjiang River.

  Water Quality of Penaeus vannamei Cultured in Pond: Design and Development on Intelligent Control System Zhang Hongyan, Yuan Yongming, Ma Xiaofei, Shen Nannan, Shi Pei 2020, 36 (11):  130-135.  DOI: 10.11924/j.issn.1000-6850.casb19030040 Abstract + ( 361 )   HTML ( 4 )   PDF ( 1475KB )   ( 125 ) Penaeus vannamei cultured in pond has more stringent requirements for water quality, the increase of unconsumed feeding and biological waste will consume a lot of water dissolved oxygen, break the water dynamic balance and lead to the increase of toxic ingredients, such as NH3-N and NO2-N, which can cause disease and even death of Penaeus vannamei, result in farmers’ economic loss and hinder the healthy development of aquaculture industry. Aiming at the above problems, we developed an intelligent water quality control system for Penaeus vannamei cultured in pond, which could monitor the water quality in real time and control the aerator, pump and other breeding equipment according to the growth habit of Penaeus vannamei. The system has the characteristics of intelligent control, reliable operation and high integration, which has achieved good results in the breeding production test, and could guarantee a safe breeding process, and effectively reduce the breeding risk of Penaeus vannamei cultured in pond.

  Taurine Affecting Growth Performance, Non-specific Immunity and Antioxidative Competence of Procambarus clarkii Kong Shengchao, Xiao Peizhen, Zhu Zhiqiang, Wang Shuang 2020, 36 (11):  136-141.  DOI: 10.11924/j.issn.1000-6850.casb20191100872 Abstract + ( 691 )   HTML ( 6 )   PDF ( 1347KB )   ( 100 ) This study aims to investigate the effect of taurine on the growth performance, non-specific immunity and antioxidative competence of Procambarus clarkii. 300 juvenile red swamp crayfish Procambarus clarkii with initial body weight of (4.50±0.50) g were selected and randomly divided into five groups. The five groups were fed with five isonitrogenous and isoenergetic diets with different taurine contents respectively. After feeding for 4 weeks, we investigated the growth performance, biochemical parameters of blood and liver. In 200 and 300 mg/kg treatment groups, some indices were significantly higher than those of the control group (P<0.05), such as the weight gain, dressing percentage, the levels of total protein (TP), lysozyme (LSZ), and the activities of superoxide dismutase (SOD) and catalase (CAT) in liver. In 200 and 300 mg/kg treatment groups, serum glutamic-pyruvic transaminase (GPT) and glutamic-oxaloacetic transaminase (GOT) were lower than those of the control group (P <0.05), which had the statistical difference. In 300 mg/kg treatment group, the activities of GSH-Px and survival rates were significantly higher than those of the control group (P <0.05), feed coefficient was significantly lower than that of the control group (P<0.05). However, there was no statistical difference in the contents of malondialdehyde (MDA) among the five groups. Therefore, the diet supplemented with 200-300 mg/kg taurine could promote the growth of Procambarus clarkii, improve the non-specific immunity and antioxidative competence, and enhance its disease resistance.

  Application of EM Bacteria in Aquaculture Deng Ru, Meng Shunlong, Chen Jiazhang, Chen Chunguang 2020, 36 (11):  142-148.  DOI: 10.11924/j.issn.1000-6850.casb19040031 Abstract + ( 626 )   HTML ( 8 )   PDF ( 1444KB )   ( 283 ) To improve the water quality, the fishery multiplication and the restoration of ecological environment, the application of EM bacteria has attracted extensive attention and become a research hotspot in recent years. This study systematically reviewed the definition and source of EM bacteria, the effect and mechanism of EM bacteria in aquaculture in recent decades, and elaborated the factors affecting the effect of EM bacteria. It is found that: EM bacteria have significant effects on regulating microbial ecological structure, reducing harmful substances in water environment, improving immunity, gaining weight and increasing yield; however, the basic theoretical research of EM bacteria technology is still relatively weak, and there are still deficiencies in the production technology and application process. Therefore, in the future, it is necessary to improve production technology, establish and improve screening system, and develop new fields of research and application of EM bacteria in aquaculture, so as to create greater economic value for aquaculture and provide the possibility for sustainable aquaculture.

  Evaluation on the Convergence of Agriculture and Tourism in Sichuan and Analysis of the Obstacles Chang Jie 2020, 36 (11):  149-156.  DOI: 10.11924/j.issn.1000-6850.casb19030063 Abstract + ( 328 )   HTML ( 1 )   PDF ( 1350KB )   ( 84 ) Promoting the in-depth convergence of agriculture and tourism is of great significance to the current structural reform of agricultural supply side and the convergence of rural industries. Therefore, it is necessary to scientifically evaluate the convergence of agriculture and tourism, and to grasp the stage characteristics and major obstacles of convergent development. Through literature analysis, this paper chose resource endowment conditions, convergent innovation level, convergent development effect to construct an evaluation index system for the convergence of agriculture and tourism. Then, the empirical analysis of Sichuan Province was carried out by using AHP method, entropy weight method and obstacle degree evaluation method. The results showed that: (1) from 2005 to 2016, the convergence index of agriculture and tourism in Sichuan showed an overall upward trend; (2) the convergent innovation index showed a downward trend year by year, and non-agricultural resource-oriented tourism products have greatly reduced the market share of agricultural themed tourism products; (3) the change in the composite effect index showed significant growth, but the combined effect of convergent development was in its infancy; (4) in general, the convergence of agriculture and tourism in Sichuan was shifting from a resource-based model to a product-oriented development model; (5) at this stage, convergent innovation level was the main obstacle that continued to affect the convergence of agriculture and tourism in Sichuan, and the obstacles were increasing year by year. Based on this, the convergence of agriculture and tourism in Sichuan Province must take the road of quality development, promote the synergy and quality development of agriculture and tourism resources, and use new technologies to further expand the diffusion of tourism knowledge and the channels for multi-subject participation, so as to comprehensively improve the quality and level of convergent development.

  Consumers’ Willingness to Buy Local Brand Fresh Maize and Analysis of Its Influencing Factors: Based on 929 Consumer Survey Questionnaire in Shanghai Wu Tianqiang, Ma Jia, Wang Hui, Yang Deli 2020, 36 (11):  157-164.  DOI: 10.11924/j.issn.1000-6850.casb18120007 Abstract + ( 316 )   HTML ( 3 )   PDF ( 1332KB )   ( 393 ) Under the background of the structural reform of agricultural supply side, through the empirical analysis of the purchase intention of Shanghai local brand fresh corn and its influencing factors, the study aims to better promote the brand building of fresh corn and provide the corresponding advices for guiding the consumption of local brand fresh corn. Through the establishment of multivariate and orderly Logit model, we quantitatively analyzed the individual characteristics, family characteristics of different consumer groups, the cognitive characteristics of consumer groups on fresh corn and the dietary preferences of consumers on the purchase intention of Shanghai brand fresh corn products and the direction of action. The results showed that: the gender, age, place of birth, education, consumer willingness to treat fresh corn as a snack, the awareness of the fresh corn production in Shanghai, the trust in the quality and safety of fresh corn products, and the place of origin were significant factors influencing consumers’ willingness to purchase local brand fresh corn. On the whole, the current information asymmetry between the market and consumer is still an important factor restricting the development of local brands and the consumption of high-quality agricultural products. Based on this, we put forward targeted suggestions from the precise positioning of consumer groups, reducing information asymmetry between market and consumer, and increasing the diversity of fresh corn products.