Current issue

• 2021 Vol.37 No.26 Published:15 September 2021

  Analysis of Tuber Yield and Sugar Content of 10 Sugar Beet Varieties in Susceptible and Non-Susceptible Areas Zhao Yaru, Shi Haoqi, Pi Zhi, Wu Zedong 2021, 37 (26):  1-8.  DOI: 10.11924/j.issn.1000-6850.casb2021-0511 Abstract + ( 398 )   HTML ( 11 )   PDF ( 1589KB )   ( 98 ) To evaluate the impact of susceptible and non-susceptible areas on root yield and sugar content of sugar beet, the root yield and sugar content of 10 sugar beet varieties were measured in 2017 and 2018 in 1 susceptible area and 6 non-susceptible areas. The experiment was a randomized complete block design, and the paired t-test and multivariate analysis of variance were adopted to analyze tuber yield and sugar content of the ten sugar beet varieties with 4 replicates. The results of multivariate analysis of variance showed that, except zone 3 in 2018, there was no significant difference in root yield among the 4 replicates in the other 6 zones in 2018 compared with 2017. Significant and non-significant differences were shown among the 10 varieties in the 7 areas in 2017 and 2018. The boxplot showed that the sugar content in 2017 and the root yield and sugar content in 2018 were significantly different between the susceptible area (zone 1) and the non-infectious areas (zone 2 to 7) (paired t-test, p<0.001, p<0.001, p<0.001). In 2017, BETA377, BETA468, ST13112, LN90905, KWS2314, SV1554, BETA379 and KWS9147 in zone 1 had no significant differences and were at a high level. In 2018, the root yield of Knhn1357 in zone 1 was significantly different from that of the other nine varieties and was at a high level. In zone 1, the sucrose content of HI0554, BETA377, Kuhn1357 and SV1554 in 2017 and HI0554, BETA468, KWS2314 and Kuhn1357 were not significantly different from each other in 2018 and were at a higher level. In 2017 and 2018, except that LN90905 and HI0554 in 2017 had significant differences, there was no significant difference in root yield and sugar content of the 10 varieties in zone 5. In 2017 and 2018, there were significant differences in root yield and sugar content in zone 1 (paired t-test, P<0.001, P =0.036). In zone 5, there was no significant difference in root yield and significant difference in sugar content among the 10 varieties in 2017 and 2018 (paired t-test, p=0.931, p<0.001). After a comprehensive assessment, ST13112, LN90905 and SV1554 are less resistant to the disease, Knhn1357, BETA377, BETA468, KWS2314, KWS9147, BETA379 and HI0554 have strong disease resistance, and there are significant differences in root yield and sugar content within the same zone and among the varieties.

  Subcritical Extraction Technology of Gossypol Rong Mengjie, Jin Yunqian, Wang Yanqin 2021, 37 (26):  9-14.  DOI: 10.11924/j.issn.1000-6850.casb2021-0675 Abstract + ( 260 )   HTML ( 6 )   PDF ( 1349KB )   ( 57 ) The experiment aims to use subcritical extraction technology to explore the optimal extraction condition of free gossypol in cotton kernels, and provide a basis for the industrial production of gossypol. Using high-phenol cottonseed as the raw material for extraction, the influence of factors such as the pretreatment method and the temperature, time, material-to-liquid ratio, and times of extraction on the extraction rate were analyzed, and orthogonal experiments were conducted to determine the optimal extraction condition. The results showed that in the pretreatment experiment, the extraction rate of crushed embryos through 40 mesh sieve was the highest, which was 57.6%; In the single factor experiment, the extraction rate of gossypol first increased and then decreased with the increase of temperature, reaching the highest 58.2% at 20 ℃. With the time increasing gradually, the growth of the extraction rate tended to be flat after 30 minutes, and gradually increased along with the number of extraction times, the growth tended to be flat after 4 times. The extraction rate gradually increased along with the material-to-liquid ratio, and became flat after the ratio reached 1:12. Orthogonal test results showed that the optimal condition for subcritical extraction of gossypol was: temperature at 20℃, time duration of 40 min, 4 times of extraction, and the material-liquid ratio of 1:14, under this condition, the extraction rate was 68.9%.

  The Heterologous Expression and Antibacterial Properties of the Bacteriocin Paracin1.7 in Lactococcus Lactis NZ9000 Pan Yue, Yang Zhixin, Yang Xiaoli, Wang Xu, Song Gang 2021, 37 (26):  15-23.  DOI: 10.11924/j.issn.1000-6850.casb2021-0463 Abstract + ( 261 )   HTML ( 6 )   PDF ( 2014KB )   ( 58 ) To obtain the bacteriocin with better antibacterial effect, this experiment used heterologous expression method to express the presumed bacteriocin protein 57AA, 62AA, 77AA, 84AA, taking the expression host of Lactococcus lactis NZ9000 and the vector of pNZ8148 to detect the antibacterial effect of heterologous expression products. The results show that the four hypothetical protein 57AA, 62AA, 77AA, and 84AA have antibacterial effects on B. subtilis. Compared with Paracin 1.7 produced by Lactobacillus paracasei HD1.7, the antibacterial activities of 57AA, 62AA, 77AA, and 84AA were improved by 7.57 times, 4.53 times, 5.89 times (very significant difference P<0.01) and 1.20 times (significant difference P<0.05), respectively. In conclusion, the heterologously expressed protein 57AA, 62AA, 77AA, and 84AA, which are putatively expressed as bacteriocins, have better antibacterial effects.

  The Regulation of Leaf Margin Serration Development in Plants: A Review Yuan Jing, Zhou Bingying 2021, 37 (26):  24-31.  DOI: 10.11924/j.issn.1000-6850.casb2021-0477 Abstract + ( 364 )   HTML ( 17 )   PDF ( 1157KB )   ( 85 ) Plants leaf is an important vegetative organ whose formation and development involves hormonal signals and complicated genetic networks regulating among different transcription factors. The occurrence of leaf margin serration is a result of long-term plant adaption to diverse environment, which is of great significance for plants to respond to high temperature, drought and other stresses, and photoperiod. In order to better understand the developmental process of leaf margin serration in plants, this paper classified and summarized the important regulatory factors and their regulatory mechanisms in the formation of leaf edge serration in plants. Development of leaf margin serration is regulated by plants hormone, such as auxin, cytokinin, and gibberellin, and transcription factors, such as NAM/CUC, TCP and SPL, KNOX gene family, and other regulatory factors. In addition, development of leaf margin serration also exhibits different regulatory patterns among plants with single or compound leaves. There are still many unknown regulatory factors of the development process of leaf margin serration in plants, therefore, it is important to explore and identify more regulatory factors in the future, and understand their underlying mechanisms, thus providing a theoretical basis for crop trait improvement through modification of leaf shape.

  Health Evaluation of Main Forest Vegetation Types in Naban River Nature Reserve Wang Weiwei, Xu Yanhong, Yang Junling, Luo Rujian, Pu Meng 2021, 37 (26):  32-39.  DOI: 10.11924/j.issn.1000-6850.casb2020-0755 Abstract + ( 251 )   HTML ( 9 )   PDF ( 1739KB )   ( 52 ) This research took four main vegetation types of the monsoon evergreen broad-leaved forest, deciduous broad-leaved forest, tropical monsoon forest and tropical montane rainforest in the Naban River nature reserve as the research objects, used principal component analysis to select 12 indicators from the 18 indicators in five categories as the forest health assessment indicators for main vegetation types, adopted Delphi expert scoring method and analytic hierarchy process to determine the weight of each index, and assessed forest health of major vegetation types of 487 small classes in reserve through the forest health assessment index method. The results show that there are 405 high quality and healthy forest small classes, accounted for 77.79% of the total area; there are 82 sub-healthy and unhealthy forest small classes, accounted for 22.21% of the total area. The health status of the main vegetation types is good, but due to the influence of community activities, the vegetation types that close to farmlands and villages have low health status, so some measures should be taken to alleviate the deterioration of the adverse situation, realize the sustainable development goal of harmonious coexistence between man and nature.

  The Accumulation of Five Heavy Metals in Different Genotypes of Brassica juncea Mi Baobin, Liu Biqiong, Dai Xiongze, Xiao Wei, Zhang Zhuqing, Zhou Huoqiang, Wang Duanhua 2021, 37 (26):  40-49.  DOI: 10.11924/j.issn.1000-6850.casb2020-0757 Abstract + ( 288 )   HTML ( 6 )   PDF ( 1470KB )   ( 49 ) The study aims to investigate the accumulation difference of five heavy metals: cadmium (Cd), arsenic (As), lead (Pb), mercury (Hg) and chromium (Cr) in different genotypes of brassica juncea, and to provide guidance on the production safety of brassica juncea in areas with complex contamination of heavy metals. Combining the heavy metal biological concentration factor and transfer factor with the single-factor contamination index method, as well as the Nemero integrated contamination method, the responses of nine different genotypes of brassica juncea to the five heavy metals were investigated in pot experiments to comprehensively evaluate the production safety of brassica juncea in heavy metal contaminated areas. The results show that Brassica juncea has strong ability to transfer heavy metals from stem to leaf, and heavy metals are mainly accumulated in the roots and leaves of brassica juncea. The individual contamination index of heavy metal Cd in different parts of brassica juncea is generally high and has large varietal difference. The contamination indexes between Pb, As, Hg and Cr show similar trend, and the differences between species and parts are not obvious. Among the varieties tested, ‘Wusiqingpeilan’, ‘Cuinengercai’, ‘Tedabangcai’ and ‘Kangresijitianzhujie’ are better brassica juncea varieties with ower heavy metal accumulation capacity. The accumulation of heavy metal in brassica juncea is related to genotype and heavy metal species, and it is feasible to select brassica juncea varieties with low accumulation of heavy metals which can be used for planting in heavy metal contaminated fields.

  Effects of Irrigation Amount and Planting Density on Biomass Allocation, Yield and Water Use Efficiency of Purple Cabbage in Arid-hot Valley Li Jiancha, Li Kun, Pan Zhixian, Sun Yi, Fang Haidong, Shi Liangtao, Zhang Lei, Yue Xuewen 2021, 37 (26):  50-57.  DOI: 10.11924/j.issn.1000-6850.casb2020-0591 Abstract + ( 288 )   HTML ( 5 )   PDF ( 1235KB )   ( 37 ) The study is to assess the effects of irrigation amount and planting density on biomass characteristics, yield, and water use efficiency of purple cabbage. The configuration effects of irrigation amount (I1 5800 m3/hm2、I2 4900 m3/hm2、I3 4600 m3/hm2) and planting density (D1 79200 plants/hm2、D2 52800 plants/hm2、D3 39600 plants/hm2) on biomass characteristics, yield and water use efficiency of purple cabbage were studied. The results showed that the fresh weight of leaf and stem, and the fraction of stem of purple cabbage were significantly affected by the irrigation amount. The allometric coefficients of outer leaf to above-ground biomass reduced with the decrease of irrigation water, so more biomass was distributed to the outer leaf of purple cabbage. The fresh and dry weight of leaf, stem and cabbage head, as well as the total biomass, increased significantly with the decrease of planting density. With decreased planting density, the fraction of outer leaf decreased significantly, but the fraction of cabbage head increased. There was no significant difference in the allometric growth of biomass in each treatment. Planting density was the main factor affecting the biomass characteristics of purple cabbage. There was a small effect of irrigation amount on the biomass of purple cabbage and the interaction between irrigation amount and planting density on biomass characteristics in purple cabbage was not significant. The principal component analysis (PCA) scores of biomass characteristics and the water utilization efficiency of I2D3 treatment were the highest, while its economic yield was good, so the I2D3 was the best among all the treatments. The study can provide a basis for high yield and high-efficiency production of purple cabbage in arid-hot Valley.

  The Photosynthesis Characteristics and Planting of Different Ploids Isatis Indigotica in the Understory Zhang Feng, Han Jinlong, Zhu Yanwei, Ni Dapeng, Shan Chenggang 2021, 37 (26):  58-65.  DOI: 10.11924/j.issn.1000-6850.casb2020-0354 Abstract + ( 250 )   HTML ( 5 )   PDF ( 1440KB )   ( 91 ) In order to study whether the understory planting of Isatis indigotica could be helpful to improve the land utilization and the production of Radix Isatidis, the authors chose diploid Isatis indigotica and tetraploid Isatis indigotica as the test materials, planted them for a full growth cycle and carried out the research depending on different canopy densities understory: canopy density less than 0.3 as mild canopy closure (C1), canopy density of 0.3-0.6 as moderate canopy closure (C2), canopy density above 0.6 as severe canopy closure (C3), and open field cultivation as control (C0). The results showed that Isatis indigotica was typical heliophyte, yet it had wide light adaptability, which could adapt to the weak light environment with less than 30% canopy. The photosynthetic capacity of tetraploid Isatis indigotica was better than that of diploid, but in weak light condition, the diploid Isatis indigotica was better-adapted than tetraploid Isatis indigotica, and the moderate canopy density understory was suitable to planting diploid Isatis indigotica. In less than 30% canopy density understory, planting tetraploid Isatis indigotica could get high benefits in production. In more than 30% canopy density understory, diploid Isatis indigotica should be chosen to plant.

  Effects of Mixed Application of Biochar-based Soil Conditioner and Specific Fertilizers on Maize Microorganism and Enzyme Activities in Soil Wu Panpan, Yang Sufen, Liu Shuwu, Wang Huanxiang, Zhang Xiaoning, Gu Limin, Liu Rui 2021, 37 (26):  66-73.  DOI: 10.11924/j.issn.1000-6850.casb2020-0857 Abstract + ( 255 )   HTML ( 8 )   PDF ( 1393KB )   ( 56 ) Field experiments were conducted to determine the effects of biochar-based soil conditioner application combined with maize-specific fertilizer (T1) and maize biologic special fertilizer (T2) on microbial population, community structure and soil enzyme activities of maize. The results indicated that compared with the control, biochar-based soil conditioner application combined with two maize-specific fertilizers could significantly improve the amounts of bacteria and actinomycetes, but reduce the number of soil fungi. The soil sucrose, urease, acid phosphatase activities increased in different degrees, while the soil peroxidase activities were not significantly different. Metabolic activity and functional diversity of soil microbial community under applying biochar-based soil conditioner combined with two maize-specific fertilizers were higher than those of the control. The principal components analysis (PCA) also demonstrated that, the T1, T2 and CK treatments were significantly different in the principal component coordinate system, indicating that the functional diversity of maize rhizosphere microbial community was significantly different. T1 and T2 treatments were more conducive to maize yield. In general, compared with farmers’ fertilization, biochar-based soil conditioner application combined with two maize-specific fertilizers has better effect, and biologic special fertilizer for maize treatment has the best effect.

  Diversity of Culturable Microorganisms in Black Swamp Soil of Caohai Wetland Under Different Land Use Patterns You Ping, Xiao Qunyin, Wang Dan, Shang Tao, Yang Jinyi, Li Yamei, Xue Xiaohui 2021, 37 (26):  74-79.  DOI: 10.11924/j.issn.1000-6850.casb2021-0313 Abstract + ( 228 )   HTML ( 4 )   PDF ( 1311KB )   ( 41 ) To explore the changes of soil microorganism in Caohai buffer zone, the distribution of culturable soil microorganisms and soil physical and chemical properties were studied under different land use patterns. The results showed that: (1) different land use patterns significantly affected the soil microbial population, the number of bacteria in cabbage and reed land was significantly lower than that in the other three land use patterns, while the number of actinomycetes in cabbage land, fungi in corn field, ammoniating bacteria in grassland, nitrogen fixing bacteria in peach tree land, cellulose decomposition bacteria in corn field and inorganic phosphorus bacterial in cabbage field were the most; (2) the effects of soil physical and chemical properties on microorganisms were different, organic matter, total nitrogen and alkali hydrolyzable nitrogen were significantly and positively correlated with the number and composition of fungi and cellulose decomposing bacteria, while organic matter and total nitrogen were significantly and negatively correlated with the number and composition of actinomycetes and inorganic phosphorus bacteria. Considering the number of soil microorganism and soil nutrient status under different utilization methods, peach tree land was the suitable land use pattern in the black swamp area of Caohai.

  Effects of Organic Materials Combined with Microbial Inoculants on the Remediation of Soil Secondary Salinization Under Greenhouse Condition Mao Xiaoxi, Guan Peibin, Ma Li, Lu Xiujun, Liu Wenju, Li Bowen 2021, 37 (26):  80-87.  DOI: 10.11924/j.issn.1000-6850.casb2020-0844 Abstract + ( 298 )   HTML ( 4 )   PDF ( 1306KB )   ( 74 ) Soil secondary salinization has become a major issue to restrict the development of agriculture under greenhouse condition. In the present study, a greenhouse experiment was conducted to explore the effects of the two organic materials (cow manure and biochar) combined with microbial inoculants on the remediation of typical soil secondary salinization in Yongqing county of Hebei Province. The treatments were: conventional fertilization without any organic materials as control (CK), conventional fertilization with the application of cow manure (DM), conventional fertilization with the application of biochar (BC), conventional fertilization with the application of both cow manure and microbial inoculant (DM+MI) and conventional fertilization with the application of both biochar and microbial inoculant (BC+MI). The contents of total soil soluble salt and soil salt ions and the height and stem diameter of chili pepper plants were determined to analyze the effects of different organic materials on soil secondary salinization. The results showed that the combination application of organic materials and microbial inoculant improved soil secondary salinization to some extent. Compared with CK, DM+MI obtained the best performance in decrease the content of soil salt, which could decrease the amount of total soil soluble salt by 18.26% and the contents of Na+, Ca2+ and Mg2+ by 24.1%, 18.75% and 24.29%, respectively, followed by DM treatment > BC+MI treatment> BC treatment. The application of organic materials stimulated the growth of chili pepper. At the 10 th week, different treatments significantly increased the height and stem diameter of chili pepper by 10.40%~16.00% and 19.50%~21.30%, respectively. The correlation analysis showed that there was a significantly negative correlation between Ca2+ and Mg2+ and the growth of chili pepper in the secondary salinization greenhouse soil. In conclusion, the application of organic materials with microbial inoculants could reduce the contents of soil salt, alleviate the soil secondary salinization, and thus promote pepper growth.

  Effects of Freeze-thaw on Soil Nitrogen Conversion: Research Progress Yu He, Xie Hongbao, Chen Yimin, Wang Yao, Sui Yueyu, Jiao Xiaoguang 2021, 37 (26):  88-92.  DOI: 10.11924/j.issn.1000-6850.casb2021-0121 Abstract + ( 235 )   HTML ( 7 )   PDF ( 1022KB )   ( 39 ) Nitrogen is one of the important nutrients limiting plant growth, and its transformation degree in soil is affected by many factors. As an important driving force for soil N transformation in mid, high latitude or high altitude areas, the effects of freeze-thaw also has a great impact on the process of soil N transformation. Based on existing research results at home and abroad, this paper summarized the effects of soil freeze-thaw cycles, freeze duration and freeze intensity on the process of soil N transformation. We summed up the general rules of soil N transformation caused by the changes of freeze-thaw patterns: changes in freezing and thawing patterns were all conducive to the mineralization of soil N. The increase of freeze-thaw intensity could significantly increase the content of soil nitrate N. Changes in freeze-thaw patterns will also increase N2O emissions.

  Intermediate Test Effect of Agricultural Lime on Acid and Cadmium Contaminated Paddy Field Fang Keming, Xiao Xin, Wang Meiling, Zhang Lu, Wang Lu, Qin Leiying, Zhang Ming, Jiang Lin, Zhu Anfan 2021, 37 (26):  93-97.  DOI: 10.11924/j.issn.1000-6850.casb2020-0744 Abstract + ( 270 )   HTML ( 6 )   PDF ( 1143KB )   ( 46 ) On the basis of previous regular experiments, this simple contrast intermediate test was carried out to further verify the effect of agricultural lime on acid soil improvement, rice yield increase and rice cadmium reduction in acid and cadmium contaminated paddy fields. The results showed that under the condition of pH 5.64 in the tested paddy field, liming of an average of 750 kg/hm2 raised the pH of the soil by 0.153 units. The average yield of rice increased by 1529.98 kg/hm2 with lime application of 3000 kg/hm2 compared with that without lime application, and the yield increase rate was 14.74%, the t-test reached an extremely significant level. The average income increased by 1738.15 yuan/hm2with lime application of 3000 kg/hm2 than that without lime application. The main reason for the yield increase was that lime application promoted the growth and tillering of rice and increased the grain weight per plant. The lime application of 3000kg/hm2 reduced the cadmium content of rice by 0.21 mg/kg, with a reduction rate of 37.8%, and the t-test reached an extremely significant level. The results indicated once again that agricultural lime application in acid and cadmium contaminated paddy fields could have good effects on improving acid soil, increasing both production and income, and reducing cadmium content in rice, which could be popularized according to local conditions.

  The Soil Moisture Threshold for Emergence of Desert Economic Plant griophyllum Squarrosum Wang Qi, Ma Quanlin, Chen Fang, Wei Linyuan, Zhang Weixing 2021, 37 (26):  98-104.  DOI: 10.11924/j.issn.1000-6850.casb2020-0647 Abstract + ( 356 )   HTML ( 4 )   PDF ( 1332KB )   ( 38 ) Emergence is the most important stage in plant growth. Determining the threshold of soil moisture during the emergence of Agriophyllum squarrosum has great significance to promote the development of wild Agriophyllum squarrosum population and its artificial planting. The pot experiment was conducted by setting temperature, sowing time and soil moisture gradients to study the changes of emergence rate of Agriophyllum squarrosum under different conditions, and to determine the suitable soil moisture content for the emergence of Agriophyllum squarrosum in aeolian sandy soil. The results showed that: (1) in laboratory, the lower limit of moisture threshold under three different temperature gradients was 10.81% (10.0 mm), 10.81% (7.5 mm) and 8.51% (7.5 mm), respectively, in outdoor, the lower limit of moisture threshold of different sowing time was 10.0 mm; (2) the water threshold for the emergence of Agriophyllum squarrosum was not only related to the periodic dormancy characteristics of seeds, but also to the ambient temperature, the higher the ambient temperature, the lower the threshold value of moisture. The study proposed the method for determining the lower limit of the moisture threshold of Agriophyllum squarrosum seedlings for the first time, which could provide basic data for the artificial planting of Agriophyllum squarrosum and the effective use of natural rainfall in the non-arable land.

  Monitoring of the Dynamic Change of Wetland Vegetation in Extremely Arid and Desert Areas: Taking Gansu Dunhuang Yangguan National Nature Reserve as an Example Ji Shuzhi 2021, 37 (26):  105-109.  DOI: 10.11924/j.issn.1000-6850.casb2020-0802 Abstract + ( 168 )   HTML ( 5 )   PDF ( 1802KB )   ( 29 ) Based on 541 Landsat 5 TM and Landsat 8 OLI images from 1988 to 2016, the normalized vegetation index (NDVI) of wetland vegetation (mainly reeds) in Xitugou and Wowachi in the extremely arid desert region was calculated, the characteristics of wetland vegetation were analyzed from NDVI, wetland vegetation area and average NDVI, the vegetation coverage of Wowachi wetland and Xitugou wetland in Dunhuang Yangguan National Nature Reserve (hereinafter referred to as Yangguan Nature Reserve) was estimated to determine the changes. According to Google Image and field survey, we determined that NDVI > 0.1 was the best threshold to identify vegetation in Xitugou and Wowachi wetlands, through the statistical calculation of wetland vegetation in the nature reserve, the change trend was studied. It was found that the wetland vegetation in Wowachi and Xitugou had an obvious increasing trend.

  Spatial-temporal Pattern Evolution of Cultivated Land in Sichuan Province from 1999 to 2018 Wang Xie, Yang Qiao, Zeng Qiguo, Zhang Jianhua, Li Jingrui, Li Yiran, Zhu Yuhong 2021, 37 (26):  110-116.  DOI: 10.11924/j.issn.1000-6850.casb2021-0473 Abstract + ( 364 )   HTML ( 9 )   PDF ( 2140KB )   ( 102 ) This study took the cultivated land area of 181 counties in Sichuan Province from 1999 to 2018 as the research object, based on principal component analysis and spatial analysis, described the spatial-temporal pattern evolution characteristics of cultivated land area in the province and explored the main driving factors. The results showed that from 1999 to 2018, the total cultivated land area in Sichuan had five stages: continuous decrease, slow increase, fluctuating change, rapid increase and stable change. In the whole process of change, the spatial change of cultivated land in the province mainly occurred in northwest Sichuan plateau and Chengdu plain. Among them, the cultivated land area of southwest Sichuan mountainous area and northwest Sichuan plateau increased, while the cultivated land area of central Sichuan hilly area, Chengdu plain area and mountainous area around basin decreased. The gravity center of cultivated land area moved southward obviously. The main driving forces of cultivated land change in Sichuan included agricultural development foundation, economic development level and geographical location. Among them, solid foundation of agricultural development was the main reason for the increase of cultivated land in northwest Sichuan plateau. The level of regional economic development and location characteristics were positively driving the change of cultivated land in the mountainous areas around the basin. The level of regional economic development is the negative driving force of the change of cultivated land in hilly area of central Sichuan. The interaction of the negative effect of economic development level and the positive effect of agricultural development foundation and location advantage resulted in the cultivated land change in Chengdu plain and southwest Sichuan mountainous area. The above conclusions could provide a scientific basis for making reasonable policies on land use and cultivated land protection in Sichuan Province.

  Analysis of Drought Characteristics and Effect on Crop Yield in Shuozhou City Xie Jianqiang, Ning Songrui, Du Peide, Wei Tianxing 2021, 37 (26):  117-123.  DOI: 10.11924/j.issn.1000-6850.casb2021-0317 Abstract + ( 220 )   HTML ( 6 )   PDF ( 1763KB )   ( 69 ) To quantify the spatio-temporal variation in drought intensity and its effects on crop yield in semi-arid area of northern Shanxi Province, based on the measured meteorological data (1972 to 2017) from 6 meteorological stations in Shuozhou, the variation trends of precipitation and temperature were investigated whilst the spatial and temporal characteristics of drought frequency and intensity at different time scales were analyzed using standardized precipitation evapotranspiration index (SPEI). The results indicated that the variation in annual average precipitation was insignificant. Average precipitation showed increasing trends in spring, autumn and winter, but a decreasing trend in summer. Specifically, only the average precipitation in autumn increased significantly. Meanwhile, the annual average temperature showed a significant upward trend, in which the most significant increment was discovered in spring. The drought frequency was the highest in 1992-2001, which was also the high frequency period of extreme drought. At the 10-year scale, the longest drought duration of SPEI-3 which represented the SPEI at short time scale (3 months) was 8 months between 1992 and 2001, while the longest drought duration of SPEI-12 was 7 months between 1982 and 1991. In Shuozhou City, crop yield was directly affected by drought characteristics with the relationship in the form of a quadratic function. Our results are expected to provide reference for the development of regional rain-fed agriculture.

  Comparative Analysis of Microbial Communities in Rhizosphere Soil of Healthy and Root-knot Nematodes-infected Tobacco Fields Zhang Renjun, Chen Yaqiong, Zhang Jiemei, Yao Zhengping, Wu Jinhu, Hou Zhengxue, Yin Honghui, Xu Tianyang, Ouyang Jin, Wang Liang, Chen Suiyun 2021, 37 (26):  124-132.  DOI: 10.11924/j.issn.1000-6850.casb2020-0778 Abstract + ( 309 )   HTML ( 5 )   PDF ( 2838KB )   ( 71 ) To study the relationship between tobacco root-knot nematode disease and rhizosphere soil microbial communities, high-throughput sequencing was used to study the microbial diversity, composition structure and function of rhizosphere soil in healthy and diseased tobacco fields. The results show that there is no significant difference in the Alpha diversity of the rhizosphere soil microbial communities between healthy and diseased tobacco fields. Beta diversity analysis shows that the distribution of samples from healthy and diseased tobacco fields is basically the same. The bacterial and fungal microbial communities in the rhizosphere soil of healthy and infected tobacco fields are similar in composition at the phylum level, but there are differences in species abundance. Acidobacteria, Actinobacteria, Basidiomycota and Chytridiomycota are dominant in healthy tobacco fields, while Proteobacteria and Gemmatimonadetes, Ascomycoda and Mortierellomycota are dominant in diseased tobacco fields. At the genus level, the microbial community composition of rhizosphere soil bacteria and fungi are basically the same, but there is significant difference in the microbial species abundance between healthy and root-knot nematode-infected tobacco fields, and the pathogenic bacteria such as Cylidrocapon, Fusarium are dominant in the diseased tobacco field. At the species level, Actinoallomurus spadix and Arhrobacter ramosus in healthy tobacco fields are significantly different from those in diseased tobacco fields. Through the prediction analysis of rhizosphere soil microbial function, it is found that the functional composition of fungi and bacteria in diseased and healthy tobacco fields are similar, but the functional abundance of diseased tobacco fields is higher than that of healthy tobacco fields. Therefore, infection of nematodes is not directly related to the composition and diversity of the rhizosphere soil microbial community, but might be closely related to the abundance of certain species and sample functional abundance. The study could provide a theoretical basis for controlling tobacco root knot nematode disease by regulating rhizosphere microbial community structure.

  The Effect of Peony Seed Meal Extract on Soil of Continuous Cropping and Control of Gaeumannomyces graminis Wu Yongling, Wei Xinping, Li Xiaoling, Wei Ting, Hu Meiqian 2021, 37 (26):  133-139.  DOI: 10.11924/j.issn.1000-6850.casb2021-0020 Abstract + ( 308 )   HTML ( 4 )   PDF ( 1439KB )   ( 43 ) To make full use of the insecticidal and antibacterial ingredients in peony seed meal, and explore the effect of different concentrations of extract on the continuous cropping soil, this study combined single factor and orthogonal experiment, soil chemical property analysis and laboratory biological active determination methods against Gaeumannomyces graminis, to determine that 60% ethanol concentration, 120 W ultrasonic power, and 50℃ temperature was the optimal extraction condition of peony seed meal effective ingredients. At the same time, in a certain concentration range, the peony seed meal extract could reduce the pH of continuous cropping soil, improve soil alkalinity, and show a “low promotion and high inhibition” effects on the organic matter content, total nitrogen, carbon to nitrogen ratio, total phosphorus and ash content. The peony seed meal extract was also found to be beneficial to increase the fungi and actinomycetes number and cellulase and urease activities. In addition, in vitro antifungal activity against Gaeumannomyces graminis with peony seed meal extract T4 (0.8 mg/mL) had a good efficacy, which could reach 63.42%. The results of this study could lay a foundation for the resource utilization of peony seed meal and the development of natural environmentally friendly fungicides.

  Progress of Multi-scale Soil Moisture Monitoring Wei Yutao, Liu Minghuan, Liu Ke, Pu Weiru 2021, 37 (26):  140-145.  DOI: 10.11924/j.issn.1000-6850.casb2021-0145 Abstract + ( 252 )   HTML ( 4 )   PDF ( 1095KB )   ( 48 ) Precise observation of soil water content at multi-scales is the key to understanding the transformation among atmospheric water, soil water, surface water and groundwater, and developing adaptive strategies to the geological hazards associated with it. General observation methods and their principles, advantages, disadvantages and adaptations were presented at multi-scales. Specially, soil water observations at large scale were achieved through soil water inversion models based on the remote-sensing information, e.g. temperature, reflectivity and other parameters developed through the combination of temperature and reflectivity. Methods and techniques used to obtain the information were also presented. Future development of soil water observations was discussed.

  Ecological Wisdom and Enlightenment of China’s Agriculture Land Use Planning Tian Changfeng, Niu Xiong, Yang Qiusheng 2021, 37 (26):  146-152.  DOI: 10.11924/j.issn.1000-6850.casb2021-0459 Abstract + ( 399 )   HTML ( 11 )   PDF ( 1134KB )   ( 126 ) To show time-honored China’s agricultural ecological wisdom, promote the integration and symbiosis of “ecological wisdom—ecological practice—ecological civilization”, we summarized the ecological wisdom and planning thinking of China’s agricultural land use through document analysis and induction of historical classics and traditional agricultural practices. The research shows that the ecological wisdom of agricultural land use in China is reflected by the favorable weather, favorable geographical position, and the emphasis on human resources. The overall ecological concept, time cycle thinking and factor planning thought are the external manifestation of the planning thinking of agricultural land use in China. In urban-rural spatial planning and rural revitalization, the wholeness mode of thinking should be set up, including conducting spatial allocation under the perspective of the community of life for man and nature to realize the people-oriented urbanization, controlling the spatial planning of the land demarcation line to lay a foundation for future spatial layout; building the system of natural parks to form a sound protection shield for national ecological safety; promoting urban-rural integration and rural revitalization to narrow the gap between urban and achieve shared prosperity; and keeping the strategic margin to realize the added value of urban-rural development. In the overall planning of land and population elements, it is advocated to give play to the subjective initiative of people. Although agricultural land use in ancient China is small-scale land use and ecological practice, its ecological wisdom is still of positive significance for understanding and promoting the practice of land spatial planning today.

  Application of Agricultural Water-saving Irrigation Technology in China: Research Progress Zhang Xu, Hu Baogui 2021, 37 (26):  153-158.  DOI: 10.11924/j.issn.1000-6850.casb2021-0010 Abstract + ( 707 )   HTML ( 7 )   PDF ( 1240KB )   ( 109 ) To form a basis for future research on the application of water-saving irrigation technology, this study sorted out different types and applications of water-saving irrigation technology in China’s current agricultural development trend, interpreted the authenticity of its sustainable development, aiming to provide reference for relevant research. With the help of CNKI database, through advanced retrieval “theme”=“irrigation technology” and “including”=“popularization and application” from literature between 2000 and 2020, a total of 679 literature involving relevant information were obtained by literature analysis method. The problems in the development of agricultural water-saving irrigation technology in China were summarized, and the corresponding solutions were provided. The results show that by analyzing the numbers and distribution of relevant literature, the research on China’s agricultural water-saving irrigation technology is in the stage of continuous improvement, and researchers should further combine water-saving irrigation technology with the actual situation. In China, micro-irrigation is the best water-saving irrigation technology. Channel water conveyance has been widely applicable in China, since it is developed, this technology has been rapidly promoted and applied throughout the country.

  Reflections on the Revitalization and Development of Rural Culture Under the Background of Digital Village Construction Sun Ning, Qu Yang, Feng Xian, Li Jin 2021, 37 (26):  159-164.  DOI: 10.11924/j.issn.1000-6850.casb2020-0768 Abstract + ( 344 )   HTML ( 8 )   PDF ( 1114KB )   ( 95 ) The revitalization of rural culture is an inevitable requirement of the Rural Revitalization Strategy and the building of a well-off society in an all-round way, and it is also an important part of the cultural prosperity of the Chinese nation. In order to speed up the construction and revitalization of rural culture, this article uses the literature deduction method and the inductive review method to study the current development status and prospects of rural culture in China. It is found that China’s rural cultural services still have difficulties that restrict the revitalization of rural culture, such as relatively backward infrastructure, single form of resource supply, imperfect governance mechanism, and shortage of digital talents. However, the development of digital technology and the implementation of the national “digital village” strategy have provided new opportunities for realizing the revitalization of rural culture, narrowing the cultural gap between urban and rural areas, enhancing rural cultural confidence, and developing characteristic cultural industries. Digital technology should be used to accelerate the revitalization of rural culture, focusing on scientific planning and policy financial support to improve rural digital cultural service infrastructure, resource supply and governance mechanisms to achieve leap-forward development of rural culture, and encourage digital consumption and cultivate digital talents to inject new momentum into the revitalization of rural culture and accelerate the process of revitalizing rural culture.