Current issue

• 2020 Vol.10 No.1 Published:22 January 2020

  The Density Tolerance of Dwarf Soybean Varieties Liu Nianxi, Dong Zhimin, Li Zhi, Chen Liang, Liu Hao, Yi Zhigang, Wang Bo, Liu Baoquan 2020, 10 (1):  1-6.  DOI: 10.11923/j.issn.2095-4050.cjas20191000225 Abstract + ( 550 )   HTML ( 17 )   PDF ( 1328KB )   ( 397 ) To clarify the reasonable dwarf and dense-planted population structure of soybean and establish a theoretical basis for super high yield breeding of soybean, four dwarf soybean varieties of different genotypes were used as materials, and eight density gradients were set up. The yield-related traits were investigated and analyzed, and the most suitable planting density was screened. The results show that the plant height gradually increases with the density increasing; the number of pods and grains per plant gradually decrease; the yield has a trend of increasing firstly and then decreasing; the lodging rate increases dramatically when the density reaches a certain degree. The optimal plant density for ‘Jimidou-1’, ‘Jimidou-2’, ‘imidou-3’ and ‘Jimidou-4’ is 400000 plants/hm 2, 375000 plants/hm 2, 400000 plants/hm 2 and 560000 plants/hm 2, respectively, and the yield reaches 4199.2 kg/hm 2, 3282.3 kg/hm 2, 3410.1 kg/hm 2 and 3313.4 kg/hm 2, respectively. Therefore, the high-yield potential of dwarf and high-density tolerant soybean varieties can be further tapped by increasing the density reasonably.

  Agronomic Traits of Flax Germplasm Resources: Relationship and Cluster Analysis Based on the R Language Zhang Lili, Geng Lige, Sun Juan, Wang Yuxiang, Qu Zhihua, Li Shifang, Qiao Haiming 2020, 10 (1):  7-12.  DOI: 10.11923/j.issn.2095-4050.cjas20190700124 Abstract + ( 401 )   HTML ( 8 )   PDF ( 1567KB )   ( 501 ) Through the research on further phenotype identification of flax germplasm resources from Hebei Province germplasm repository, we aim to explore the correlation of the resources’ agronomic traits, and provide a certain base for flax breeding. We took 499 flax germplasm resources as materials, and used R language to conduct the correlation analysis of flax agronomic traits to get their correlation coefficients, and carried out the cluster analysis. Research results showed that: the weight per plant had a significantly positive correlation with the stem number, the branch number of main stem and the effective number, while the plant height had a significantly positive correlation with the stem length. Clustering analysis showed that the 499 germplasm resources were divided into 3 groups, group 1 was suitable for high yield breeding, while group 2 for lodging resistance breeding.

  Phenotypic Traits of Potato Germplasm Resource: Genetic Diversity Analysis Yang Chun, Qi Haiying 2020, 10 (1):  13-21.  DOI: 10.11923/j.issn.2095-4050.cjas20190500054 Abstract + ( 640 )   HTML ( 15 )   PDF ( 3909KB )   ( 682 ) To understand the genetic diversity of introduced potato germplasm, and provide reference for parent matching of potato varieties breeding in Shanxi, the shannon-wiener index, correlation, principal component and cluster analysis of germplasm resources were conducted by selecting 11 qualitative traits and 10 quantitative traits. The results showed that the diversity indexes of quality traits ranged from 0.42 to 1.52, and the diversity indexes of potato shape, skin color and flesh color and plant type were higher. The genetic diversity indexes of yield, plant height, growth period and tuber number per plant in quantitative traits were higher, which were ≥2.0. The results of correlation analysis showed that the yield was positively correlated with seedling emergence rate, commercial potato rate, tuber number per plant, plant height, growth period and single potato weight. Principal Component Analysis (PCA) determined four principal components, including the single potato weight, growth period, specific gravity and plant height. And the cumulative contribution rate was 83.997%. The germplasm resources were divided into four groups by cluster analysis, including medium-early maturity and low-yield type, medium-early maturity and high-yield type, medium-late maturity and high-yield type, medium-late maturity and low-yield type. The results of comprehensive analysis show that the germplasm resources have rich genetic diversity, among which the second germplasm group could be used as excellent resource for early maturity and high yield breeding, and the third germplasm group could be used as parent material for multi-objective character breeding.

  Strawberry Leaves Infected by Colletotrichum fragariae: Effect of Temperature and Humidity Zhao Dailin, He Haiyong, Yang Xuehui 2020, 10 (1):  22-26.  DOI: 10.11923/j.issn.2095-4050.cjas19030005 Abstract + ( 484 )   HTML ( 7 )   PDF ( 1512KB )   ( 460 ) To provide a basis for exploring the condition of latent infection of strawberry leaves infected by Colletotrichum fragariae, we studied the morbidities and the differences of infection characteristics of strawberry leaves infected by Colletotrichum fragariae in vitro by regulating the indoor temperature and humidity. The results showed that: the combinations of temperature and humidity of 25℃/85%, 20℃/80%, 15℃/80%, 10℃/80%, 15℃/75% and 10℃/75% all could cause disease after being inoculated 7 d, however the treatment of 10℃/70% could cause slight disease after being inoculated 28 d. The differences of infection characteristics showed that: 25% of conidia germinated after being inoculated 6 h of treatment of 25℃/85%; after 12 h, appressorium began to form and the formation rate was 16%; after 48 h, sporadic disease spots began to appear on the leaves; after 7 d, a mass of tissue cells of leaves began to decompose, and the disease index was 39.07; in the treatments of 10℃/70%, after 1 d, 2.88% of conidia germinated; the germination rate of the conidia was 100% and 8.83% appressorium began to form after being inoculated 24 d; after 28 d, sporadic disease spots began to be appear on the leaves and the disease index was 1.85; after 42 d, a mass of tissue cells of leaves began to decompose and typical anthracnose disease spots were found on the leaves. In conclusion, 10℃/70% is close to the baseline of temperature and humidity condition of strawberry leaves infected by Colletotrichum fragariae, and the incubation period can reach 28 d under the condition.

  The Significance, Development and Prospect of Integrated Crop-livestock System Wang Xiquan, Yang Yadong, Zhang Kai, Zhao Jie, Zeng Zhaohai 2020, 10 (1):  27-31.  DOI: 10.11923/j.issn.2095-4050.cjas18090008 Abstract + ( 574 )   HTML ( 11 )   PDF ( 1060KB )   ( 465 ) The integrated crop-livestock system can not only achieve sustainable and intensive food production (grain and livestock products), but also conducive to soft landing of national economy, and it may still be one of the dominant modes of agriculture production in the future. The authors reviewed the significance of integrated crop-livestock system and its primary coverage and determinant factors, based on the literatures at home and abroad. The results show that: the essence of crop-livestock integration is a process of improvement in intensification, specialization and systematism. The crops and by-products of the food industry needed to feed animals have increased rapidly over the past century. Currently, approximately 30% of the world’s arable land is used to produce animal feed, and roughly the same rate of fertilizer was consumed in animal feed production. Furthermore, the total nitrogen accumulation of animal manure produced by livestock is higher than that of global synthetic nitrogen fertilizer. Overall, strengthening the balance of nitrogen and phosphorus within the integrated crop-livestock system is of great beneficial to agriculture sustainable development, and reinforcing the research and extension of integrated crop-livestock system has great potentials for the green development of agriculture in China.

  Rice Areas Contaminated by Cadmium in Hunan: Key Issues to be Addressed in Ratoon Rice Development Chen Jiwang, Tu Naimei, Yi Zhenxie, Chen Pingping 2020, 10 (1):  32-36.  DOI: 10.11923/j.issn.2095-4050.cjas20190500036 Abstract + ( 401 )   HTML ( 13 )   PDF ( 1099KB )   ( 371 ) The paper aims to promote the healthy development of ratoon rice in Hunan. Under the background of developing ratoon rice vigorously in Hunan, according to the research results on the prevention and control of cadmium pollution and the ratoon rice in Hunan, and combined with the present situation of soil and rice cadmium pollution and the advantages of ratoon rice, we summarized the loopholes in the current study of ratoon rice contaminated by cadmium, and pointed out key problems to be solved in cadmium contamination of ratoon rice in the future: (1) evaluating the safe production of ratoon rice in cadmium-contaminated areas to varied degrees; (2) clarifying the regulating effect of agronomic measures on cadmium absorption and distribution in ratoon rice; (3) integrating the safe and high-yield cultivation technology system for ratoon rice in cadmium-contaminated area.

  Response of Bio-available Phosphorus and Water-soluble Phosphorus to Phosphorus Accumulation in Soil Tong Wenbin, Qiu Zhiteng, Zhang Mingkui 2020, 10 (1):  37-42.  DOI: 10.11923/j.issn.2095-4050.cjas18100017 Abstract + ( 466 )   HTML ( 9 )   PDF ( 1262KB )   ( 630 ) Taking cultivated land in four kinds of landforms in Zhejiang, including river valley plain, river network plain, coastal plain and hilly area, as the examples, the changing characteristics of bio-available phosphorus and water-soluble phosphorus with total phosphorus accumulation in soil were studied. The results showed that soil bio-available phosphorus and water-soluble phosphorus increased obviously with the increase of total phosphorus accumulation, there was a changing point in the increase. When soil total phosphorus reached 0.80-0.95 g/kg, the bio-available phosphorus increased significantly with the increase of soil total phosphorus accumulation. When the bio-available phosphorus was at 42-62 and 165-265 mg/kg, respectively, the soil water-soluble phosphorus level had two obvious increasing processes. Overall, the critical value of the accumulated total soil phosphorus was relatively low when soil bio-available and water-soluble phosphorus changed significantly in the valley plain. Since the proportion of readily available phosphorus in the total soil phosphorus increases with increasing phosphorus accumulation in soil, it is concluded that controlling the excessive accumulation of total phosphorus in soil could effectively reduce the loss of soil phosphorus.

  Straw Returning of Zizania caduciflora: Effects on Concentrations of Some Pollutants in Surface Water of Agricultural Field Zhou Yang, Yao Yueliang, Shi Lizhen, Chen Jianxia, Zhang Mingkui 2020, 10 (1):  43-49.  DOI: 10.11923/j.issn.2095-4050.cjas18120029 Abstract + ( 364 )   HTML ( 3 )   PDF ( 1407KB )   ( 332 ) To understand the effects of straw returning on the pollutants in the surface water of agricultural field and the possible non-point source pollution during the production of Zizania caduciflora, a simulation experiment was carried out to study the effects of straw returningof Zizania caduciflora as mulching or mixture with soil under flooded conditions (0%, 0.5%, 1%) on the concentrations of pollutants, such as COD, N, and P in surface water of agricultural field. The results showed that: the conductivity, COD, concentrations of P, K, Fe and Mn in surface water increased obviously at the beginning of the experiment, reached a peak on the 20 th-30 th day, and then gradually decreased to a relatively stable state; the peak concentration of NH4 +-N in surface water appeared in the first 10 days; the conductivity and the concentrations of COD, P, K, Fe and Mn increased with the increasing amount of straw returning, while the concentration of NH4 +-N decreased; the effects of straw returning of Zizania caduciflora as mulching on the conductivity, and concentrations of COD, P, K, Fe and Mn in surface water of field were greater than those of straw returning as mixture with soil; N application with straw returning could increase obviously the conductivity and NH4 +-N concentration of surface water. Straw returning of Zizania caduciflora as mixture with soil is better than straw returning as mulching, and the discharge of surface water should be controlled during the first 30 days of straw returning.

  Nitrate Nitrogen Concentrations in the Upstream of Miyun Reservoir: Spatial Distribution Pattern Wang Qingsuo, Sun Dongbao, Tang Zhiyang, Lu Yongxin 2020, 10 (1):  50-55.  DOI: 10.11923/j.issn.2095-4050.cjas18100005 Abstract + ( 353 )   HTML ( 3 )   PDF ( 1484KB )   ( 469 ) To reveal the spatial distribution laws of nitrate nitrogen ($NO_{3}^{-}$-N) concentration in the upstream of Miyun reservoir and its main influencing factors, we collected water samples throughout the whole watershed in the upstream of Miyun reservoir, and investigated the data on human activities such as population, land use types and fertilizer application, determined the concentration of $NO_{3}^{-}$-N by a flow injection analyzer. The results showed that: the concentration of $NO_{3}^{-}$-N in Chaohe River in the eastern upstream of Miyun reservoir was higher than that in the Baihe River in the western upstream; the spatial distribution pattern of $NO_{3}^{-}$-N concentration was closely related with human activities; the concentration of $NO_{3}^{-}$-N tended to rise in the way of livestock farms, settlements and farmland, while it tended to decrease in the way of dams, canyons and forests; so, the rank of $NO_{3}^{-}$-N concentration in the stream passing through different land uses was: livestock farm> settlements>farmland>dams>canyons>forests. The concentration of $NO_{3}^{-}$-N was positively correlated with population density, proportion of cultivated land, and fertilizer nitrogen application.

  Acid Rain in Agricultural Planting Areas of Ulanhot: Characteristics’ Analysis and Prevention and Control Measures Zhao Aihui 2020, 10 (1):  56-59.  DOI: 10.11923/j.issn.2095-4050.cjas19010017 Abstract + ( 297 )   HTML ( 4 )   PDF ( 1181KB )   ( 289 ) To find out the temporal and spatial variation and distribution characteristics of acid rain in the agricultural planting areas of Ulanhot, Xing’an League, Inner Mongolia, and take effective prevention and control measures to reduce the impacts of acid rain, based on the pH value, conductivity and acid rain frequency of 446 precipitation samples from 2006 to 2015, the author conducted a statistical analysis. The results showed that: the annual precipitation average pH value fluctuated and decreased, the average conductivity decreased, the acid rain frequency ranged from 1.9% to 3.6%; the acid rain grade was weak acid rain and belonged to acid rain occasional area; according to the precipitation levels, the pH value of rainstorm and light rain was the smallest and the largest, respectively; the conductivity of light rain and rainstorm was the largest and the smallest, respectively; according to the four seasons, the pH value was the lowest in summer and the highest in spring, and the conductivity was the lowest in summer and the highest in spring; according to wind direction, the pH value of ESE wind direction and SSE wind direction was the smallest and the largest, respectively; the conductivity of E wind direction and SW wind direction was the largest and the smallest, respectively. As the pH value fluctuates and decreases, it is suggested that relevant departments should explore new energy sources, such as solar energy, water energy, wind energy, etc. Gas emissions from industrial production should be discharged after reaching the standard, and plants with sulfur dioxide absorption capacity, such as spruce and oriental arborvitae, should be planted in the surrounding areas of the city.

  Distribution Prediction of Invasive Species Flaveria bidentis in China: Based on MaxEnt Model and Climate Change Scenario Li An, Li Liangtao, Gao Mengmeng, Chen Xi, Lu Tong, Liu Shuaishuai 2020, 10 (1):  60-67.  DOI: 10.11923/j.issn.2095-4050.cjas20190700109 Abstract + ( 408 )   HTML ( 11 )   PDF ( 2455KB )   ( 523 ) The paper aims to analyze the potential suitable distribution area of the invasive species Flaveria bidentis in China. Based on the maximum entropy model (MaxEnt) and ArcGIS software, we predicted the potential suitable distribution area of Flaveria bidentis in China in current and future climate conditions. The results showed that: in the current climate conditions, Flaveria bidentis was mainly distributed in most parts of Hebei, southern Beijing, northern Henan and western Tianjin; in the future climate conditions, the suitable distribution range of Flaveria bidentis would be further expanded; around 2060, the area of the high-adapted area of Flaveria bidentis would increase to 147300 km 2 with a growth rate of 121.49%, mainly distributed in Hebei and surrounding areas, Xi’an in Shaanxi and surrounding cities. The Jackknife method was used to calculate the influence of each environmental variable on the species distribution, the main factors affected the distribution of Flaveria bidentis were the minimum temperature of coldest month, the mean temperature of coldest season, annual mean temperature, the mean temperature of driest season, standard deviation of seasonal altitude and temperature changes, the mean temperature of wettest season and the mean temperature of warmest season. The AUC of the model was 0.987, indicating the accuracy of the model was very high. The distribution of Flaveria bidentis in the future climate change scenario will be further expanded, the relevant departments should pay close attention and take protective measures as soon as possible.

  Effects of Different Cultivation Modes on Yield and Agronomic Traits of Sand-pressed Watermelon Guo Song, Liu Shengfeng, Yu Rong, Tian Mei, Dong Rui, Wang Zhiqiang, Yang Wanbang 2020, 10 (1):  68-71.  DOI: 10.11923/j.issn.2095-4050.cjas20190500032 Abstract + ( 354 )   HTML ( 3 )   PDF ( 1256KB )   ( 350 ) The paper aims to solve the resource and ecological problems caused by unreasonable water supplement in sand-pressing watermelon cultivation, using ‘W03-15×W08-15’ and ‘Jincheng 5’ as experimental materials. A random block experiment was conducted with 4 cultivation methods to study the yield and agronomic traits of sand-pressing watermelon under different cultivation modes. The results showed that the yield of drip irrigation and film mulching cultivation (FD) was the highest. The dry matter accumulation, stem diameter, leaf area index and sugar content under FD were significantly higher than those under the other 3 modes, and the differences among the 4 cultivation modes were significant. The study is of certain significance to the development of water-saving agriculture in Xiangshan of Zhongwei.

  Genetic Analysis of Citrus Germplasm Resources in Fujian by ISSR Markers Zhao Yijie, Lin Lixia, Yao Liping, Luo Zhijian, Hu Zhangqiong 2020, 10 (1):  72-76.  DOI: 10.11923/j.issn.2095-4050.cjas18080021 Abstract + ( 398 )   HTML ( 3 )   PDF ( 1559KB )   ( 446 ) ISSR molecular marker techniques were used to detect the genetic diversity of 21 Citrus germplasms from Fuzhou, to provide a basis for the identification of varieties and the development of new varieties. A total of 162 bands were generated from 14 ISSR primers, of which polymorphic bands were 129, and the polymorphism percentage was 79.63%. The results indicated that, as analyzed by NTSYS-pc2.10e, all the 21 resources could be divided into five groups, 13 Fuzhou Citrus resources were clustered into the same group, and then could be divided into four subgroups. Citrus germplasm from Fuzhou can be distinguished by ISSR markers, and the genetic diversity of Citrus in Fuzhou is rich.

  Ancient Trees of Litchi chinensis var. fulvosus: Resource Investigation Zhang Huiyun, Gao Xianyu, Wang Yuequan, Wang Yongfen, Song Yunlian, Zuo Yanxiu, Zhang Cuixian, Li Xiufeng, Rao Xiang, Luo Xinping 2020, 10 (1):  77-81.  DOI: 10.11923/j.issn.2095-4050.cjas19010001 Abstract + ( 360 )   HTML ( 10 )   PDF ( 2209KB )   ( 536 ) Lychee was originated in China. To develop, innovate and utilize the ancient tree resources for lychee breeding is an important task. Through an investigation of the ancient tree resources of Litchi chinensis var. fulvosus, the situation of the resources was systematically grasped, the specific resources were collected and preserved, and a basis for the follow-up lychee breeding research was provided. In addition, the research progress of the investigation on Chinese lychee ancient tree resources, the selection and breeding of germplasm resources and the functional components of L. chinensis var. fulvosus were summarized. The distribution of L. chinensis var. fulvosus resources in Yunnan with the longitude from 101.70° to 103.88° E, the latitude from 22.57° to 25.03° N and the height from 93 m to 1441 m, the growth condition, ripening period, leaf and fruit characters and quality were analyzed. Finally, the problem of the near-death of the ancient L. chinensis var. fulvosus tree resources and suggestions on protection were pointed out.

  Analyzing Fertilizer Science and Agricultural Development of Ancient China Based on Historical Records as Qi Min Yao Shu Zhao Wen, Liu Yannan, Wang Siming, Gu Peng 2020, 10 (1):  82-87.  DOI: 10.11923/j.issn.2095-4050.cjas20191000243 Abstract + ( 447 )   HTML ( 9 )   PDF ( 1189KB )   ( 2864 ) Qi Min Yao Shu, written by Jia Sixie, is a masterpiece of agricultural science in the 6 th century of ancient China, and it is also the dividing line of the historical records of China’s ancient fertilizer science. A large amount of fertilizer knowledge of ancient northern China is recorded in Qi Min Yao Shu, and the description focuses not only on the Northern Wei Dynasty, but also on the historical records of fertilizer science in northern China since the Qin and Han Dynasties. In order to provide references for the implementation of the current agricultural modernization and rural revitalization strategy, the study also refers to some chapters concerning fertilizer from the historical materials such as Fan Sheng Zhi Shu and Wang Zhen Nong Shu, aiming to present the level of knowledge and application of fertilizer in ancient China objectively.

  The Development of Guangxi Selenium-enriched Agricultural Products Brand Yang Yiyuan, Liu Yongxian, Tan Jun, Pan Liping, Su Xinhui, Chen Jinping, Lan Xiu, Fan Zhilian 2020, 10 (1):  88-92.  DOI: 10.11923/j.issn.2095-4050.cjas18090023 Abstract + ( 394 )   HTML ( 3 )   PDF ( 1136KB )   ( 484 ) By analyzing the current situation of brand building of selenium-rich agricultural products in Guangxi, the authors summarize the problems existing in the process of brand building, including: the number of brands is large and scattered, the brand positioning of enterprises is vague, the brand awareness is weak, the industrial chain is single, and the sales channels are not diversified, etc. In view of these problems, this study puts forward practical development countermeasures, such as building regional ‘gold products’, establishing brand awareness, and set up multiple financing channels, so as to promote the brand development of selenium-rich agricultural products in Guangxi, and enhance the competitiveness of selenium-rich agricultural products and their industries in Guangxi. Speeding up the brand strategy of selenium-rich agricultural products in Guangxi is conducive to the development of regional agricultural economy, it is not only an important measure to strengthen the competitiveness of agricultural products, but also a guarantee to enhance the reputation and quality of products.

  Agricultural Green Science and Technology Development upon Black Soil Ma Jing, Du Yong, Chen Pengfei, Wei Zheng, Liu Rongzhi 2020, 10 (1):  93-96.  DOI: 10.11923/j.issn.2095-4050.cjas20190900183 Abstract + ( 436 )   HTML ( 4 )   PDF ( 1030KB )   ( 333 ) Northeast China, with vast black soil land, is the vital grain base of the country. In order to implement the instructions made by Xi Jinping, the general secretary of the CPC Central Committee, during his field visit in Heilongjiang Province, boost agricultural modernization in black soil region and improve rural revitalization in Northeast China, China Association of Agricultural Science Societies held a Forum on Agricultural Green Science and Technology Development in the New Era in June 28 th, 2019. In this Forum, academicians and experts discussed frontiers and hotspots of Agricultural Green Science and Technology as well as approaches and directions of Northeast China’s further agricultural green development, called for the black soil conservation and food production being put in an equally significant position, and indicated directions for Agricultural Green Science and Technology Development and Northeast China’s overall revitalization.

  The Role of Societies of Agricultural Sciences in Promoting Rural Revitalization Li Lidong, Gu Peng 2020, 10 (1):  97-100.  DOI: 10.11923/j.issn.2095-4050.cjas20190500028 Abstract + ( 431 )   HTML ( 4 )   PDF ( 1031KB )   ( 382 ) From the perspective of adhering to political guidance, taking full advantage of industry characteristics, devoting to rural revitalization, better serving agricultural science and technology workers and the issues of agriculture, farmers and rural areas, combined with the working reports of the Party committees of 16 agricultural science and technology societies, we summarized their characteristics, and briefly carried out the discussion from three aspects of upholding the leadership of the Communist Party of China, serving the issues of agriculture, farmers and rural areas, and uniting agricultural scientific and technological workers. In view of the problems existing in domestic social organizations, we analyzed the causes of the existing problems and put forward suggestions such as implementing the ‘four synchronization’ system of the Party building of the societies, consolidating the societies’ competence through the Party construction, and cultivating talents of the Party building.