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• 2024 Vol.14 No.1 Published:20 January 2024

  Effects of Sowing Dates and Foliar-applied Fertilizers on Grain Yield and Mineral Concentrations of Different Maize Varieties YAN Wei, LI Xiaojing, JIANG Yuwei, HUANG Meng, LIU Bo, ZHANG Chunyan, CUI Zhenling, XUE Yanfang 2024, 14 (1):  1-9.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0017 Abstract + ( 108 )   HTML ( 6 )   PDF ( 1613KB )   ( 75 ) To investigate the effects of sowing date and foliar-applied fertilizers on grain yield and mineral concentrations of the two maize varieties, field experiment was conducted in Linyi City, Shandong Province from May to October in 2019. A three-factor split plot experimental design was adopted, the main plots consisted of five maize sowing dates (May 31, June 6, June 13, June 21 and June 28, marked as B1-B5), and the sub-plots consisted of two maize varieties including ‘Denghai 605’ and ‘Zhengdan 309’. The slit-split plots consisted of five foliar-applied fertilizers, including deionized water (Water), calcium chloride (Ca), zinc sulfate (Zn), glutamine (N) and mixed solution of glutamine and zinc sulfate (N+Zn). Samples were collected at maturity. The results showed that both ‘Denghai605’ and ‘Zhengdan309’ had the highest grain yield at B3 date (June 13), and the average maximum yield was 11.9 and 10.9 t/hm2, respectively, mainly due to the higher number of grains per ear at this sowing date. The result indicated that B3 was the best sowing stage in this region, and both early and late sowing dates decreased the grain yield of the two maize varieties. For ‘Denghai605’, foliar spraying with N solution could slightly increase grain yield under early sowing conditions (e.g. B1 and B2), while foliar spraying with Ca, Zn, N and N+Zn solutions could increase grain yield under late sowing conditions (e.g. B4 and B5). Among them, foliar spraying of N + Zn solution had the best yield increase effect, and the grain yield under B4 and B5 sowing dates increased by 45.5 % and 16.0 %, respectively, compared with the control. For ‘Zhengdan309’, foliar spraying of N solution or Zn solution could improve the grain yield at B4 and foliar spraying of Ca solution could also improve the grain yield at B5. In addition, foliar applications of Zn solution alone or the mixture of N+Zn solution could significantly increase grain Zn concentration of the two maize varieties sown at B2 and B3 dates. Furthermore, foliar application of Zn solution could also significantly increase the concentrations of Fe, Mn, Cu, N and Mg in grain of ‘Zhengdan309’ sown at B2 and B3. The results provided theoretical basis for realizing high yield and quality cultivation of maize and improving fertilizer utilization efficiency.

  Dynamic Study on Filaments and Seed Setting Rate of Maize Inbred Lines YANG Meili, WANG Bangtai, LU Hongwei, SU Yujie, ZHAO Shuzheng, CHENG Jianmei, WANG Jing, GUO Hua, WANG Zhihong, QIN Guiwen 2024, 14 (1):  10-14.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0050 Abstract + ( 64 )   HTML ( 2 )   PDF ( 1247KB )   ( 31 ) The aim was to investigate the dynamic changes in filament vitality and seed setting of different maize inbred lines. This study used maize inbred lines ‘Xun 696’, ‘Xun 573’, ‘Xun 503’, ‘Zheng 58’ and ‘Chang 7-2’ as experimental materials to measure relevant indicators such as daily filament length and quantity, filament setting rates and ear traits at different days. The results showed that the daily filament length and filament setting rate of different inbred lines increased first and then decreased; the peak of the daily spinning length of the flower silk was on the 2nd to 3rd day of spinning; the peak setting rate was on the 3rd to 5th day of silk spinning. The daily filament amount showed a ‘fast-slow’ growth pattern, with a rapid growth from the 1st to the 3rd days. The total amount of ‘Xun 696’ filament was the smallest, and the total amount of ‘Chang 7-2’ filament was the largest. On the 8th day after pollination, the fertilization rate and total fruiting rate of small flowers were higher than that on the 5th day, with ‘Zheng 58’ having the highest fertilization rate and ‘Xun 696’ having the highest total fruiting rate. The fruiting rate of silk at different days of age in ‘Xun 696’, ‘Xun 573’, and ‘Xun 503’ was significantly or extreme significantly positively correlated with various traits of their panicles, daily silk production, and silk production length. The research results provide a theoretical basis for clarifying the active time of the filaments of inbred lines, mastering the optimal pollination period, improving the seed setting and seed production yield of inbred lines.

  Effects of Density and Leaves Left on Growth, Yield and Quality of Flue-cured Tobacco ‘NC297’ WU Hao, WEN Yi, LIN Yunhong, XIONG Qian, XU Wei, YANG Maosong, ZHOU Youhai, WANG Ge, DU Yu, BAI Yuxiang, WANG NA, ZHOU Peng 2024, 14 (1):  15-21.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0036 Abstract + ( 60 )   HTML ( 0 )   PDF ( 1296KB )   ( 19 ) In order to study the supporting cultivation measures of the new flue-cured tobacco variety ‘NC297’ in Chuxiong tobacco-growing area, and determine the suitable planting density and number of leaves left, the orthogonal test with three levels of planting density and number of leaves left of flue-cured tobacco ‘NC297’ was designed. The results showed that the density of 13800 plants/hm2 and 18 leaves per plant had the largest plant height, leaf length and leaf width. The disease index of black shank, bacterial wilt, climate spot and common mosaic disease were significantly lower in the medium to low density treatment group than in the high-density control group. Net photosynthetic rate, CO2 concentration, stomatal conductance and transpiration rate of low density treatment all were at a high level. The planting density of 15100 plants/hm2 and 20 leaves per plant showed the best appearance quality, followed by the treatment with the density of 13800 plants/hm2 and 18 leaves per plant. The density of 13800 plants/hm2 and 18 leaves per plant treatment had significantly higher average prices and the highest proportion of medium to high quality tobacco, and high yield. The output value was only second to the treatment with planting density of 16600 plants/hm2 and 18 leaves per plant. The treatment with a density of 13800 plants/hm2 and 18 leaves had the most coordinated chemical composition and the highest total score. According to the results of this experiment, the suitable planting density of flue-cured tobacco ‘NC297’ in Chuxiong tobacco area is 13800 plants/hm2, and the suitable number of leaves left for topping is 18 per plant.

  Effects of Planting Density and Nitrogen Application Rate on Growth and Yield of Rapeseed ZHAO Kaiqin, ZHANG Yusong, YAN Linxiang, LI Genze, LI Qinggang, LUO Yanqing 2024, 14 (1):  22-28.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0027 Abstract + ( 82 )   HTML ( 0 )   PDF ( 1259KB )   ( 33 ) To explore the effects of nitrogen fertilizer and planting density on the growth and yield of Brassica napus L, ‘Yunyouza 28’ was used as materials to measure the growth period, agronomic traits, dry weight and yield under different treatments. 3 density gradients (D1: 150000 plants/hm2, D2: 285000 plants/hm2, D3: 420000 plants/hm2) and 4 nitrogen application levels (N1: 0 kg/hm2, N2: 75 kg/hm2, N3: 150 kg/hm2, N4: 225 kg/hm2) were set for the study. The results showed that under the same planting density, the whole growth period was extended with the increase of nitrogen application, the root neck diameter, leaf area, and total and green leaf numbers increased at the beginning and then decreased with the increase of nitrogen application under D1 density at flowering stage. Dry matter weight and yield both increased firstly, reached the maximum value under D1N2 and then decreased with the increase of nitrogen application under each density. Under the same nitrogen application, the whole growth period was shortened with the increase of planting density. The root neck diameter, total leaf numbers, green leaf numbers and leaf area decreased with the increase of planting density at bolting and flowering stage. The dry matter weight and yield decreased with the increase of planting density in various periods. Planting density and nitrogen fertilizer had little influence on early growth and development, mainly from bolting and flowering stage. Planting density had greater effects on the yield and dry matter weight than nitrogen application, which affected the yield through the number of effective pods per plant. With the interaction of density and nitrogen fertilizer, D11N2 treatment (density of 150000 plants/hm2, nitrogen application amount of 75 kg/hm2) was the best, which had the highest plant height, the highest total number of leaves and green leaves, root neck diameter and leaf area, and the highest yield per plant and per unit area.

  Breeding of a New Cotton Variety ‘Xumian 608’ Suitable for Machine Picking with Early Maturity and High Quality ZHAO Mingming, HU Xinyan, LI Weihua, LI Ke, WANG Kang, CHEN Xiaoguang 2024, 14 (1):  29-33.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0007 Abstract + ( 62 )   HTML ( 0 )   PDF ( 1213KB )   ( 27 ) Aiming at the problems such as grain and cotton competition for land, excessive labor and increasing labor costs in cotton production, a new early-maturing cotton variety ‘Xumian 608’ was bred by cross-breeding technology with ‘Lumian 19’ as female parent and ‘Xu Mian 266’ as male parent. ‘Xumian 608’ can meet the one year two-harvest planting system of wheat (garlic, oil) and cotton, and is suitable for mechanized harvesting. In the regional trial of new cotton varieties in Jiangsu Province from 2018 to 2019, the growth period of ‘Xumian 608’ was 99 days, the lint percentage was 40.1%, and the lint yield of ginned cotton was 1221.0 kg/hm2, which was 3.9% higher than that of the control ‘Zhong mian Suo 50’. The plant height was 87.5 cm and the first fruit branch height was 20.8 cm, which met the standard of machine-picked cotton plant type. The average length of the upper half part of the fiber was 28.1 mm, the specific breaking strength was 29.2 cN/tex, and the micronaire value was 5.1. In the production test of Jiangsu Province in 2020, the average lint yield was 1340.3 kg/hm2, which was 10.5% higher than that of the control ‘Zhong mian Suo 50’. This variety was suitable for promoting and planting in the early-maturing cotton areas in Jiangsu Province, Yangtze River basin and Yellow River basin. It showed tolerance to wilt, verticillium and salt, resistant to bollworm and sensitivity to defoliating agents.

  Control Effect and Safety of Different Soil-applied Herbicides in Cotton Field ZHANG Huachong, ZHAO Shuqi, YAN Zhenhua, DAI Baosheng, HUANG Xiaoli, ZHANG Xin, LI Wei 2024, 14 (1):  34-38.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0031 Abstract + ( 71 )   HTML ( 0 )   PDF ( 1150KB )   ( 31 ) In order to screen out suitable soil-applied herbicides in this area, the safety and weed control effects of seven soil-treated herbicides on cotton were compared and analyzed by using soil sealing treatment in field plot experiment. The results showed that there was no significant difference in the germination rate and first section of branch of ‘Gangmian No.11’ under different treatments compared with the control, but the fresh weight, plant height and the number of fruit branches increased, indicating that the soil-applied herbicides were safe for cotton. The results of field efficacy showed that 50% prometryn wettable powder (WP)+33% pendimethalin emulsifiable concentrate (EC), 50% prometryn WP+960 g/L metolachlor EC and 50% prometryn WP+50% acetochlor EC had better control effects on grasses and leaved weeds. The average fresh weight control effect of 45 d was 83.32%, 84.08% and 80.57%, respectively, which were significantly different from that of single treatment, and the lasting time was longer. 50% prometryn WP+33% pendimethalin EC, 50% prometryn WP+960 g/L metolachlor EC and 50% prometryn WP+50% acetochlor EC are recommended to be used for weed control in cotton field.

  Establishment of Droplet Digital PCR Detection Method of Candidatus Liberibacter asiaticus SONG Xiaobing, HUANG Feng, CUI Yiping, PENG Aitian, YUE Maofeng 2024, 14 (1):  39-43.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0040 Abstract + ( 76 )   HTML ( 0 )   PDF ( 1453KB )   ( 29 ) Huanglongbing disease is a devastating disease of citrus industry in the world. Diseased seedlings, scions and field diseased plants are the primary infection sources of the disease. The establishment of a set of ultra-sensitive detection method for pathogen is important for the early warning and prevention of Huanglongbing disease. In this study, specific primers were designed according to the 16S rDNA gene sequence of Candidatus Liberibacter asiaticus, and a detection method based on droplet digital PCR technology was explored and established, and the sensitivity and detection accuracy of the method was evaluated. The test results showed that the microdroplet digital PCR detection method for Huanglongbing disease established in this study had strong specificity and high sensitivity, and its detection sensitivity was 10 times that of fluorescence quantitative PCR. The microdroplet digital PCR detection technology established in this study provides a new method for the early detection of Huanglongbing disease in citrus seedlings.

  Study on the Relationship Between Cultivated Land Quality and Landscape Pattern Index--Taking Yingtan City of Jiangxi Province as An Example ZOU Hengyu, YE Yingcong, KUANG Lihua 2024, 14 (1):  44-52.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0168 Abstract + ( 54 )   HTML ( 0 )   PDF ( 2725KB )   ( 23 ) Studying the relationship between cultivated land quality and landscape patterns can provide a scientific basis for strengthening the protection and enhancement of national cultivated land quality. Using 2022 cultivated land quality data in Yingtan City, Jiangxi Province, the study comprehensively analyzed the overall cultivated land quality situation in Yingtan based on the cultivated land quality evaluation. Landscape pattern indices such as patch area, percent of landscape, edge density, patch density, landscape shape index, mean patch size, landscape division index, contagion index, and Shannon’s diversity index were selected to calculate in Fragstats 4.2 software, and then cultivated land area weighted average national natural level index, cultivated land area weighted average national use level index and cultivated land area weighted average national economic level index were correlated with the selected cultivated landscape pattern indices, respectively. It was concluded that the cultivated land quality national natural level index was significantly and negatively correlated with the edge density of cultivated land, with a correlation coefficient of -0.393 (P<0.01); the cultivated land quality national use level index was significantly and positively correlated with the mean patch size of cultivated land and the Shannon’s diversity index, with correlation coefficients of 0.343 (P<0.01) and 0.416 (P<0.01), respectively; the cultivated land quality national economic level index was significantly and negatively correlated with the edge density of cultivated land, with a correlation coefficient of -0.381 (P<0.01). Thus, there was a clear correlation between some of the landscape pattern indices and cultivated land quality, which could reflect to some extent the correlation between cultivated land quality and landscape pattern indices within the region. The results of the study can provide scientific references for the improvement and protection of cultivated land quality from the perspective of landscape pattern, and also have certain practical significance for the national level decision-making on the optimization of regional spatial layout of cultivated land.

  Effects of Wenshan Polygonatum kingianum on Soil Fungal Community Structure PENG Cuixian, WANG Can, CAI Qunhu, LI Ling, ZHANG Xingheng, TAO Yonghong 2024, 14 (1):  53-58.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0039 Abstract + ( 67 )   HTML ( 0 )   PDF ( 1838KB )   ( 22 ) Microorganisms are closely related to the growth and development of medicinal plants. To understand the structural differences between the fungal communities of 3-year-old Polygonatum kingianum rhizosphere and bulk soil, Polygonatum kingianum rhizosphere soil (X) and bulk soil (CK) were collected and their fungal communities were analyzed for diversity based on ITS rDNA. The results showed that the top 3 fungi in the rhizosphere soil and bulk soil were Basidiomycota (CK 45.35%, X 34.48%), Ascomycota (CK 25.55%, X 36.35%) and Rozellomycota (CK 25.88%, X 23.34%), respectively. There was no significant difference between treatments Ace and Chao1 in the diversity analysis, but X 0.91 was significantly (P=0.037) higher than CK 0.86 in Simpson. Unweighted Unifrac principal coordinates analysis showed that PCoA1 (31.43% of explanation) separated CK and X treatments, which differed significantly less similar (R2=0.544, P=0.008). Analysis of variance showed that only Mortierellomycota was significantly different (P=0.006), X (4.78%) was significantly higher than that of CK (1.13%). LefSe analysis showed that Mortierellomycota was significantly enriched in the inter-root soil and was the main microorganism responsible for significant differences between treatments. Soil EC, effective N, effective P, etc. and Basidiomycota and Mortierellomycota in the samples were significantly associated (P≤0.05). Among them, the differential fungus Mortierellomycota was significantly positively associated with organic matter and significantly negatively associated with effective N, P, pH and EC values. Planting Dianthus caryophyllus significantly changed the fungal community structure in the soil and promoted significant enrichment of probiotic bacteria such as Mortierellomycota. The results of the study lay the foundation for the screening and excavation of beneficial microorganisms and biotrophic bacteria of Polygonatum kingianum, and provide technical support for the control of soil-borne diseases of Polygonatum kingianum through the regulation of rhizosphere microorganisms, and also provide new ideas for microbial breeding and cultivation of other medicinal plants.

  Quality Grading Standard of Malania oleifera Seedlings LI Ling, YANG Qingsong, CHEN Ding, PENG Cuixian, SUN Hongwei, ZHAO Dawei, TAO Yonghong 2024, 14 (1):  59-64.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0038 Abstract + ( 45 )   HTML ( 0 )   PDF ( 1246KB )   ( 21 ) Quality grading standards for Malania oleifera seedlings in line with the actual production needs is formulated, which can provide reference for M. oleifera seedling breeding and standardized production. 20 batches of M. oleifera seedlings were randomly selected from the main production area of M. oleifera in Funing County, Yunnan Province. 11 indicators were measured, including fresh weight, plant height, leaf number, leaf length, leaf width, ground diameter, main root length, main root diameter, lateral root number, chlorophyll content, and nitrogen content. The data were analyzed by using principal component and K-value clustering analysis, and then combined with actual production to determine the grading standards of M. oleifera seedlings. M. oleifera seedlings were divided into three levels with determining plant height, main root length, and ground diameter as the grading standards. Grade I seedlings: plant height≥ 33.33 cm, main root length≥ 8.00 cm, ground diameter≥ 0.23 mm; Grade II seedlings: 33.33 cm> plant height≥ 27.77 cm, 8.00 cm> main root length ≥ 7.90 cm, 0.23 mm> ground diameter≥ 0.21 mm; Grade III seedlings: 27.77 cm> plant height≥ 21.29 cm, 7.90 cm> main root length≥ 6.41 cm, 0.21 mm> ground diameter≥ 0.19 mm. In this study, the formulation of quality standards for seedlings is coincident with actual production and can provide a theoretical basis for the production of M. oleifera seedlings.

  Research Progress of Actinidia Arguta Based on Citespace Visual Analysis LIU Bo, FU Haibin, LIU Yangyang 2024, 14 (1):  65-71.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0042 Abstract + ( 70 )   HTML ( 1 )   PDF ( 1864KB )   ( 43 ) In order to systematically understand the research status and trend of Actinidia arguta in recent years, and to help relevant researchers to understand the current situation in this field, based on bibliometric, 712 articles that met the inclusion criteria were visually analyzed using CiteSpace software by searching the relevant literature of CNKI from 1979 to 2022. The knowledge map of literature, authors, research institutions and hot spots of A. arguta were analyzed. The results showed that both the authors and research institutions of the most articles were from Liaoning and Jilin Province. The hot keywords included seed-bearing mother shoot, callus, tissue culture, etc. Emerging hot topics in recent years included polysaccharide, cultivation techniques, etc. Scholars have carried out extensive and in- depth research on A. arguta from multidisciplinary fields. In future, more efforts should be made to strengthen the conversion of basic research into practical application.

  Patent Analysis of Robotic Milking Machine in China ZHAO Huimin, DING Fang, CHENG Guoming, WU Jizhou, NIE Yingli 2024, 14 (1):  72-82.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0030 Abstract + ( 51 )   HTML ( 0 )   PDF ( 2182KB )   ( 16 ) In-depth study of the patent layout of the robotic milking machines in China is of great significance for Chinese technology research and protection. Based on the Derwent Innovation (DI) patent database, using the bibliometric method and topic clustering, the layout characteristics of the robotic milking machine in China are analyzed and summarized from the aspects of annual change of patent application, technology exporting country, patentee, patent legal status, classification defined by experts, IPC classification, research focus, etc. The analysis results showed that China started slowly in this field and entered a period of technological development in 2011. The key patentees of this technology were concentrated, the overall invalid patents accounted for 41%, and the patent maintenance was not strong. Foreign institutions had more effective patent ratios and technical directions in China than domestic institutions. Patent applications by foreign institutions accounted for 22.6%, mainly from Sweden, Germany, Netherlands and the United States, and patentees mainly included DeLaval and GEA. Among domestic institutions, Anhui Yomo Machinery Group Co. and Shandong Chengcheng Iot Technology Co. had more authorized and effective patents. Foreign institutions had more patents than Chinese institutions in advanced technology directions such as automatic teatcup attacher, automatic cluster remover, automatic teat identification equipment, mechanical arm and powerplant of automatic teatcup attacher or remover, automatic attaching or detaching of clusters. It is recommended that Chinese institutions should establish effective cooperation mechanisms such as patent pools, strengthen cooperation between companies, universities, and research institutions, and strengthen the overall patent layout and cutting-edge technology patent layout.

  Research Progress of Catechin in Pu 'er Tea DENG Hongyan, MAO Jingchun, MAO Jianfu, ZHOU Qin, TAO Bo, ZHAO Long 2024, 14 (1):  83-89.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0051 Abstract + ( 86 )   HTML ( 6 )   PDF ( 1352KB )   ( 40 ) As the main matters of polyphenolic compounds in tea, catechins have free radical elimination, anti-aging, anti-radiation, weight loss, blood lipid reduction, cancer prevention and other active functions, accounting for 12%~24% of the tea. Due to the special variety and processing technology, the catechin content in Pu 'er tea is higher than other tea varieties, which shows excellent efficacy in terms of nutritional value and health care. This paper mainly describes the types of catechin, extraction measurement methods, content variations and efficacy researches of Pu 'er tea, so as to provide reference for the further development and utilization of functional catechin products in Pu' er tea.

  Analysis of the Effect of Digital Economy Empowering High-Quality Agricultural Development in Shandong Province DING Huiyuan, WANG Shouchen 2024, 14 (1):  90-100.  DOI: 10.11923/j.issn.2095-4050.cjas2023-0160 Abstract + ( 104 )   HTML ( 2 )   PDF ( 1394KB )   ( 141 ) Seizing the opportunity of the digital economy era in the new period and accelerating the process of valorization of data elements are of great significance for the high-quality development of agriculture. The article used the panel data of 16 cities in Shandong Province’s from 2015 to 2021, to accurately calculate the level of the digital economy and the degree of quality development of agriculture of Shandong Province and the 16 cities under its jurisdiction. The results show that, the level of the digital economy and quality development of agriculture has been steadily improved, but the regional differences are obvious, and the gap is relatively large; the agricultural quality development in Shandong Province has been significantly promoted by the digital economy, and the promotion effect is better in the areas with good marketization and urbanization; the digital economy empowers high-quality agricultural development by enhancing the potential of talent resource development and regional innovation and development vitality; there is a threshold effect in the impact of Shandong Province's digital economy on high-quality agricultural development. Based on this, the article proposes countermeasures and suggestions to improve the level of digital infrastructure construction in agriculture and rural areas, enhance the penetration of digital economy in all aspects of the agricultural industry chain, and improve the ability of farmers to apply digital technology.