Current issue

• 2022 Vol.38 No.8 Published:15 March 2022

  Effects of Two Plant Growth Retardants on Plug Seedling Quality of Sunflower JI Hongting, ZHAO Hanwei, WANG Yong, ZENG Yannan, CHENG Rundong, WANG Qingnan, ZHAO Hejuan 2022, 38 (8):  1-8.  DOI: 10.11924/j.issn.1000-6850.casb2021-0328 Abstract + ( 346 )   HTML ( 9 )   PDF ( 1299KB )   ( 69 ) This study aims to investigate the effects of two plant growth retardants on plug seedling quality of sunflower under high temperature and high humidly condition in summer, and to select their suitable spraying concentrations. The experiment was conducted including two plant growth retardants (paclobutrazol and uniconazole) and five spraying concentrations (0、200、400、600、800、1000 mg/L). The results showed that the foliar spraying of paclobutrazol and uniconazole significantly reduced the plant height (PH) and leaf area (LA), increased the ratio of stem diameter (SD) to PH (SD/PH) and enhanced the leaf SPAD and root dry weight. The enhanced leaf SPAD under the two growth retardants’ treatments alleviated the inhibition on LA. In addition, LA×SPAD could comprehensively reflect the changes of shoot dry weight (SDW) and plant dry weight (PDW). Based on the SD, PH, LA and SPAD, a strong seedling index (${{I}_{2}}=\frac{SD}{PH}\times \sqrt{LA\times SPAD}$) of sunflower plug seedlings under the two growth retardants’ treatments was established. The established strong seedling index had a significant correlation with the conventional strong seedling index (R2=0.9097**). The analysis of strong seedling index showed that the suitable spraying concentration of paclobutrazol and uniconazole was 400 mg/L and 600 mg/L, respectively. In conclusion, this study clarifies the effects of paclobutrazol and uniconazole on plug seedling quality under high temperature and high humidity in summer, and selects their suitable spraying concentrations. Our results could provide a theoretical basis for rational application of paclobutrazol and uniconazole in sunflower plug seeding in summer.

  Histone Deacetylases (HDACs) Gene Family in Sugar Beet: Identification and Functional Prediction WANG Linyu, JIANG Yichen, YU Qingyang, WU Zedong, PI Zhi 2022, 38 (8):  9-16.  DOI: 10.11924/j.issn.1000-6850.casb2021-0767 Abstract + ( 378 )   HTML ( 4 )   PDF ( 2888KB )   ( 1861 ) To identify vernalization-related histone deacetylases (HDACs) in sugar beet genome, HMMsearch and Blastp were employed to identify the members of BvHDACs gene family, and iqtree program was used to construct the maximum-likelihood phylogenies. The chromosome location and gene structure of BvHDACs were analyzed by TBtools. The expression pattern of BvHDACs under vernalization was measured by RNA-seq. The results showed that there were 16 BvHDACs located on 5 chromosomes. BvHDACs were classified into 3 subfamilies, namely RPD3/HDA1, SIR2 and HD2, and members from the same subfamily had similar functional domain. According to RNA-seq, the expression of several genes from RPD3/HDA1, SIR2 and HD2 significantly changed after vernalization. Especially, the expression of BvHDT1 and BvHDT2 were correlated with changes of bolting-related phenotype. The protein-protein interaction prediction showed that BvHDT1 and BvHDT2 possibly interacted with BvFLD, BvJMJ11 and BvJMJ12, which were involved in flowering and bolting. In summary, it is hypothesized that BvHDT1 and BvHDT2 may be involved in vernalization of sugar beet.

  TIFY Gene Family in Sugar Beet: Whole Genome Identification and Bioinformatics Analysis GONG Yongyong, DUANMU Huizi 2022, 38 (8):  17-24.  DOI: 10.11924/j.issn.1000-6850.casb2021-0831 Abstract + ( 391 )   HTML ( 4 )   PDF ( 3251KB )   ( 56 ) TIFY transcription factors play an important role in regulating plant growth and development as well as stress response, therefore, the purpose of this study is to identify and analyze TIFY transcription factors in sugar beet (Beta vulgaris L.). Based on the genome data of sugar beet, bioinformatics techniques were used to identify and analyze the members of sugar beet TIFY family at the whole genome level. The results showed that there were 21 TIFY genes in sugar beet with low sequence similarity. Collinearity analysis showed that only BvTIFY15 and BvTIFY18 had gene replication events. The family of BvTIFY transcription factors included 2 TIFY proteins, 8 JAZ proteins, 6 ZML proteins and 5 PPD proteins. Protein-protein interaction prediction showed that members of the JAZ family played an important role in the regulation of JA signaling. This study analyzed the structure and function of BvTIFY genes and discovered the salt stress responsive genes BvTIFY13 and BvTIFY15 in sugar beet roots. It can provide a theoretical basis for subsequent functional studies on BvTIFY genes.

  The Reduced-representation Genome Sequencing Technology: Application in Plant Genetic Analysis DONG Yuqing, WEI Xueping, QIANG Tingyan, ZHANG Bengang, QI Yaodong, LIU Haitao 2022, 38 (8):  25-32.  DOI: 10.11924/j.issn.1000-6850.casb2021-0380 Abstract + ( 472 )   HTML ( 8 )   PDF ( 1223KB )   ( 1314 ) Reduced-representation Genome Sequencing (RRGS) is a technology developed on the basis of next-generation sequencing to sequence specific regions based on enzyme digestion to reduce the complexity of the genome. This methodological step is simple, low cost, independent of the reference genome, and enables molecular markers at the genome-wide level. This paper summarizes the development process and main technical types of RRGS, and sums up the application of RRGS in plant genetic map construction, quantitative trait locus mapping, and population genetic analysis. At the same time, the defects and deficiencies in the analysis of population genetics by RRGS are put forward, in order to provide reference for the research methods of plant genetic evolution, trait mapping, and etc.

  Nano-selenium Prepared by Biological Method: Research Progress and Application Prospect YIN Tingting, LI Zhihui, SU Jiahe, WU Shidi, XU Hongyan, HE Shuai, LIU Pei, LI Xiangqian 2022, 38 (8):  33-41.  DOI: 10.11924/j.issn.1000-6850.casb2021-0378 Abstract + ( 407 )   HTML ( 13 )   PDF ( 1246KB )   ( 3194 ) Selenium is one of the trace elements required by human body, and it is very important for the survival and development of human beings. As a new type of bio-nanotechnology, the method of researching and preparing nano-selenium has attracted more and more attention and has broad application prospects. This article summarizes three methods of preparing nano-selenium, which are physical method, chemical method and biological method. It also introduces the synthesis of nano-selenium by biological method. This synthesis method has mild reaction conditions and fast reaction, and is pollution-free and sustainable, which is the best synthesis method among the three. This article also summarizes the common methods for characterizing nano-selenium in the past five years at home and abroad, such as transmission electron microscopy, Fourier infrared spectroscopy, X-ray diffraction and ultraviolet-visible absorption spectroscopy, and discusses the application direction of the selenium industry such as plant selenium supplementation, animal selenium supplementation and drug development, aiming to provide new ideas for the preparation of nano-selenium, and to explore the application prospects of nano-selenium.

  Effects of Calcium Supply with Varying Levels on the Growth and Development of Woody Ornamental Plants DONG Wencai, LIU Xianbin, LI Hongmei, ZHAO Shuangmei, BAO Jinmei, SHEN Jianping, LIANG Fang, LU Mei 2022, 38 (8):  42-50.  DOI: 10.11924/j.issn.1000-6850.casb2021-0376 Abstract + ( 315 )   HTML ( 2 )   PDF ( 1257KB )   ( 101 ) To explore the possibility of controlling the vegetative and reproductive growth of woody ornamental plants by adjusting the amount of calcium fertilizer application in urban landscaping, this study took the woody ornamental plant ‘Portia tree’ as the research object, and set seven different levels of calcium concentrations on the basis of Hoagland nutrient solution to investigate the external morphological growth indexes of ‘Portia tree’ individuals and the growth data of various organs. The results showed that under the condition of 100% calcium concentration, the plant height, root length and stem diameter of ‘Portia tree’ individuals reached the maximum, which were (126.67±4.81) cm, (105.00±4.04) cm and (24.07±0.84) mm, respectively; and under the condition of 1% calcium concentration, the plant height, root length and stem diameter were the minimum of the 7 calcium concentrations, which were (10.67±1.20) cm, (19.33±2.96) cm and (2.20±0.12) mm, respectively. Under the condition of 100% calcium concentration, the total biomass, leaf dry weight, stem dry weight and root dry weight of ‘Portia tree’ individuals reached the maximum, which were (348.02±12.01) g, (119.85±5.68) g, (157.29±6.39) g and (50.89±0.94) g, respectively; and under the condition of 1% calcium concentration, the total biomass, leaf dry weight, stem dry weight and root dry weight were the minimum of the 7 calcium concentrations, which were (10.24±0.81) g, (3.92±0.39) g, (3.05±0.39) g and (3.28±0.13) g, respectively. Under the two calcium concentrations of 100% and 150%, the flower buds of ‘Portia tree’ individuals appeared about 65 days after the treatment; while, no flower buds appeared under the three calcium concentrations of 1%, 10% and 300%. This study demonstrates that the concentration of calcium nutrient in Hoagland nutrient solution is more suitable for the growth and development of woody ornamental plant ‘Portia tree’, but extremely low or high calcium concentration are not conducive to the growth of vegetative organs in the early stage and the transformation to reproductive growth stage in the later stage.

  Effects of Different Organic Materials on Root Characteristics and Accumulation of Nitrogen, Phosphorus and Potassium in Flue-cured Tobacco HUANG Hao, XIE Jin, YUAN Wenbin, WANG Chuliang, CHEN Kunhua, ZENG Fandong, LIANG Zengfa, SU Zhao, WANG Wei 2022, 38 (8):  51-57.  DOI: 10.11924/j.issn.1000-6850.casb2021-0863 Abstract + ( 290 )   HTML ( 3 )   PDF ( 1310KB )   ( 40 ) To explore the effects of different organic materials on the root characteristics and the aboveground part NPK accumulation of flue-cured tobacco, the effects of three organic materials, namely steam explosion straw, peat and biochar, on the physical and chemical properties of the tobacco soil, tobacco root characteristics and the aboveground part NPK accumulation were investigated in a pot experiment with ‘Yunyan 87’ as the material. The results show that the physical properties of tobacco plant soil, such as soil bulk density and total porosity, are significantly improved by the addition of organic materials, especially biochar and peat. The root length density is greater in the lower soil layer and soil farther from the main root axis, and the development of primary lateral roots and adventitious roots is better under biochar or peat treatment compared with those under steam explosion straw treatment. Organic matter, alkaline N, available phosphorus and available potassium content in the soil are significantly increased after organic material treatment, with the most obvious effect observed in biochar and peat treatment. The typical correlation between root characteristics and plant NPK accumulation shows that there is a positive correlation of 0.999. Organic materials could improve soil properties, increase effective nutrient content, promote root development, deep rooting and diffusion, and increase the aboveground part NPK accumulation, with the most significant effect of biochar treatment, followed by peat treatment.

  Effects of Biogas Residue Application on Nutrient and Heavy Metal Content in Soil and Yield of Crops Under Peanut-wheat Rotation QIN Naiqun, MA Qiaoyun, GAO Jingwei, YANG Pu, CAI Jinlan, HAO Yingchun, LI Yanmei, JI Hongce, LIAO Xiangzheng 2022, 38 (8):  58-63.  DOI: 10.11924/j.issn.1000-6850.casb2021-1069 Abstract + ( 364 )   HTML ( 5 )   PDF ( 1151KB )   ( 40 ) To study the effects of biogas residue application on nutrient and heavy metal content in soil and yield of crops under peanut-wheat rotation, field experiments were carried out including six fertilizer treatments, i.e., 1.5×104 kg/hm2 (A1), 3.0×104 kg/hm2 (A2), 4.5×104 kg/hm2 (A3), 6.0×104 kg/hm2 (A4), 7.5×104 kg/hm2 (A5) and no biogas residue treatment (CK, A6), with the application of 750 kg/hm2 compound fertilizer as basal fertilizer in each treatment. The grain yield of crops, the heavy metal content in grains, and the soil nutrient and heavy metal content were determined respectively. The results showed that the yield of peanut using biogas residue increased by 4.74% to 9.03% compared with that of the control, the yield of A2, A3, A4 and A5 was significantly higher than that of control (A6) (P<0.05); the yield of wheat using biogas residue increased by 3.08%-7.38% compared with that of the control, the yield of A2, A3, A4 and A5 was significantly higher than that of control (A6) (P<0.05); treatment A2 had significantly higher yield of peanut and wheat compared with that of A6, and the lowest biogas residue using amount, so it was the appropriate application amount of biogas residue. Compared with no biogas residue application, the addition of biogas residue significantly increased soil nutrients’ content, the content variation range of soil organic matter, total nitrogen, available phosphorus, available potassium was 56.80-107.23 g/kg, 0.26%-0.45%, 93.77-128.67 and 218.33-329.67 mg/kg, respectively. Hg and As were not detected in peanut or wheat grains, and the content of Pb, Cd and Cr changed in the range of 0.023-0.07, 0.11-0.23 and 0.015-0.062 mg/kg, respectively, all lower than The National Food Safety Standard Maximum Levels of Contaminants in Foods (GB 2762—2017). The soil content of Hg, Pb, Cd, Cr and As was 0.046-0.061, 23.4-29.7, 0.09-0.22, 71.1-89.5 and 12.0-14.4 mg/kg, respectively, all were lower than The Soil Environmental Quality - Agricultural Land Soil Pollution Risk Control Standard (Trial) (GB 15618—2018).

  Water and Fertilizer Utilization Characteristics of Winter Wheat Under Different Yield Levels WU Zhibin, HUANG Chao, LEI Yuan, JING Feng, LIU Zhandong 2022, 38 (8):  64-71.  DOI: 10.11924/j.issn.1000-6850.casb2021-0339 Abstract + ( 336 )   HTML ( 4 )   PDF ( 1453KB )   ( 122 ) According to the requirement characteristics of different winter wheat yields on fertilizer in Huang-Huai-Hai area, formula fertilization was carried out to simulate different yield levels of winter wheat and study the characteristics of growth and development as well as water and fertilizer utilization under different yields, so as to provide a theoretical basis for the efficient use of water and application of fertilizer. The experiment was conducted in Xinxiang Comprehensive Experimental Base of Chinese Academy of Agricultural Sciences from 2018 to 2019. We set four yield levels, including 7.50 t/hm2 (C0), 8.25 t/hm2 (C5), 9.00 t/hm2 (C10) and 9.75 t/hm2 (C15), with no fertilization as control (CK). The results showed that all the indicators of the plant height, SPAD, ear number per hectare, ear length, grains per ear, 1000-grain weight and biomass of winter wheat increased with the increase of yield, while the invalid spike number decreased. Compared with those of CK treatment, the plant height, SPAD, ear number per hectare, ear length, grains number per ear, 1000-grain weight and biomass of C15 treatment increased by 17.8%, 69.1%, 68.6%, 15.3%, 16.5%, 17.3%, 34.9%, respectively, and the harvest index was 53.2%. With the increase of yield, the water consumption of winter wheat increased significantly, and water use efficiency (WUE) showed an upward trend. Water consumption and water use efficiency of C10 increased by 22.8% and 9.9%, respectively. After harvest, the total nitrogen and total phosphorus in soil of C10 treatment increased significantly compared with those before sowing, while those of C15 treatment decreased significantly. Fertilizer contribution rate increased significantly with the increase of yield, but the partial productivity of fertilizer decreased significantly. The increase of winter wheat yield mainly depends on high ear number per hectare and dry matter accumulation during the whole growth period. Considering the yield, water consumption and water use efficiency of winter wheat, the C10 treatment is considered to be the best one.

  Investigation and Evaluation of Soil Nutrients in Fruit Coconut Orchards in Hainan Province LU Lilan, WANG Yuping, YIN Xinxing, HUANG Yingkai, FAN Haikuo 2022, 38 (8):  72-80.  DOI: 10.11924/j.issn.1000-6850.casb2021-0533 Abstract + ( 473 )   HTML ( 4 )   PDF ( 1580KB )   ( 137 ) By investigating the soil nutrient status of main coconut orchards in Hainan Province and evaluating the soil fertility, the study aims to provide a basis for understanding the soil nutrient status of the coconut planting areas and the fertilization management in the province. Collecting the surface soil (20 cm) of coconut plantations in the northern (Haikou), eastern (Wenchang), southern (Sanya, Lingshui), central (Qiongzhong, Tunchang) and western (Changjiang) of Hainan, we determined soil nutrients and performed correlation and difference significance analysis. The results show that the pH of most survey sites is acidic; the coconut soil has high organic matter, NPK, calcium and magnesium content in central and northern Hainan, but low organic matter and NPK content in the coastal areas, especially in Wenchang. The three trace elements of copper, zinc and iron are not deficient in the survey samples; however, all the soil samples are deficient in B content. Through suitable fertilization and cultivation measures, the soil fertility level and fertility retention capacity of coastal areas in Hainan, such as Sanya, Lingshui, Wenchang and other places, could be improved to meet the needs of coconut growth and development; in addition, the application of B fertilizer should be enhanced in coconut orchards in Hainan Province.

  Effects of Biochar Application on Saline-alkali Soil: Research Status WANG Lina, YANG Ying, Du Su 2022, 38 (8):  81-87.  DOI: 10.11924/j.issn.1000-6850.casb2021-0993 Abstract + ( 542 )   HTML ( 5 )   PDF ( 1223KB )   ( 3667 ) Saline-alkali soil is an important type of low and medium yielding soil in China, and due to soil degradation, saline-alkali land has become an important reserve arable land resource. Biochar has been more and more widely recognized as a soil conditioner, carbon sequester and slow-release carrier of fertilizers in agriculture, and has great application prospects in promoting the sustainable development of agriculture. By comprehensively analyzing the research progress of biochar application on physicochemical properties, content change of nutrients, soil microorganisms and crop biomass of saline-alkali soil, we studied the improvement effects of biochar on saline-alkali soil and summarized its possible mechanism of soil improving, with a view to providing support for saline-alkali land management.

  Distributional Characteristics of Soil Carbon in Moist Evergreen Broad-leaved Forest in Ailao Mountains of Yunnan Province ZHAO Shuangmei, LIU Xianbin, LI Hongmei, DONG Wencai, SHEN Jianping, BAO Jinmei, LIANG Fang, LU Mei 2022, 38 (8):  88-95.  DOI: 10.11924/j.issn.1000-6850.casb2021-0354 Abstract + ( 343 )   HTML ( 4 )   PDF ( 2258KB )   ( 421 ) By investigating the distributional pattern of soil carbon with various properties in two types of soil profile in a subtropical forest ecosystem, the primary soil and warp soil were analyzed and explored for their important roles in the process of soil carbon cycle. We conducted the study in a subtropical mountainous moist evergreen broad-leaved forest in the Ailao Mountains of Yunnan Province, took the primary soil in the forest area with high altitude and the warp soil in the shrubby-meadow area with low altitude as sampling sites, collected soil samples in different soil layers along the two types of soil profile, and focused on the vertical distribution pattern of soil carbon with various properties including soil total organic carbon, labile organic carbon, microbial biomass carbon, dissolved carbon and water dissolved carbon in the soil layers with most plant roots (0-45 cm). The results show that the concentrations of all determined soil carbon with different properties decrease exponentially along the two types of soil profile. The concentrations of soil total organic carbon, labile organic carbon and water dissolved carbon in the warp soil are statistically higher than those in the primary soil; the concentration of soil microbial biomass carbon is not statistically different between the two types of soil; and the concentration of dissolved carbon in the warp soil is significantly lower than that in the primary soil, indicating that the primary and warp soil play different roles in storing and circulating soil carbon with different properties in the subtropical mountainous moist evergreen broad-leaved forest ecosystem in the Ailao Mountains. The results adequately demonstrate that although the vertical distribution pattern of soil carbon with various properties in different soil profiles of the same subtropical forest ecosystem is consistent, the average storage has obvious spatial heterogeneity. The paper could provide a new theoretical basis and research direction for the estimation of soil carbon with different properties in the global tropical and subtropical forest ecosystems and the study on soil carbon cycle in different types of soil profile.

  Effects of Salt Stress on Physiological and Growth Traits of Alfalfa LIU Qingsong, JIA Yanli, XIAO Yu, GUO Zhiding, JI Mingmei, ZHAO Zhongxiang, HUANG Sufang, YUE Mingqiang, LIU Zhen, YAN Xudong, XU Yupeng 2022, 38 (8):  96-101.  DOI: 10.11924/j.issn.1000-6850.casb2021-0343 Abstract + ( 304 )   HTML ( 2 )   PDF ( 1136KB )   ( 261 ) To improve the saline-alkali soil in eastern Hebei, we selected the heavy saline-alkali soil and sandy loam soil in Huanghua of eastern Cangzhou in Hebei Province to mix in different proportions, and explored the growth and physiological characteristics of salt-tolerant and salt-sensitive alfalfa under salt stress. The results showed that different proportions of saline-alkali soil could inhibit the growth of alfalfa. When saline-alkali soil: sandy loam soil was no more than 1:2, the plant height, aboveground biomass, the number of main branches and lateral branches, underground biomass and root length of ‘Zhongmu 3’ had no significant difference; when the proportion was less than 1:2, salt stress could promote the growth of ‘Zhongmu 3’; but when saline-alkali soil: sandy loam soil exceeded 1:2, salt stress had a significant inhibition effect on the growth of ‘Zhongmu No.3’. The salt-sensitive variety ‘WL440HQ’ showed that with the proportion of saline-alkali soil increased, the plant height, above-ground biomass, underground biomass, number of main branches and lateral branches and root length decreased significantly. Salt stress increased the content of proline and malondialdehyde in the leaves of alfalfa. The proline and malondialdehyde content of ‘Zhongmu 3’ increased in the seedling stage to early flowering stage under the treatment of YJ-2 (saline-alkali soil: sandy loam soil = 1:2), indicating that the variety had the strongest adaptability in saline-alkali soil: sandy loam soil=1:2. In the heavy saline-alkali land in eastern Cangzhou, the mixing ratio of saline-alkali soil: sandy loam soil = 1:2 will not affect the normal growth of salt-tolerant alfalfa variety ‘Zhongmu 3’, and can improve the use of local saline-alkali soil.

  Vegetation Cover Response to Groundwater and Precipitation Changes in Minqin Desert Oasis XUE Wenrui, YANG Zihui, ZHANG Yong, GUO Shujiang, WANG Qiangqiang, ZHANG Jianhui 2022, 38 (8):  102-109.  DOI: 10.11924/j.issn.1000-6850.casb2021-0379 Abstract + ( 319 )   HTML ( 3 )   PDF ( 1908KB )   ( 225 ) The growth of desert vegetation is constrained by groundwater and atmospheric precipitation. Vegetation in most areas of Minqin desert oasis is unable to use groundwater due to continuously declining groundwater level. Precipitation is increasing slightly year by year, and it has become the main water source of vegetation growth. Thus, it is of great significance for oasis protection to study the influence of groundwater level and precipitation on vegetation in Minqin desert oasis. This paper used groundwater observation data and annual precipitation data combined with NDVI data retrieved by remote sensing from 2000 to 2018, to explore the impact of annual precipitation and groundwater on vegetation cover in Minqin desert oasis. The results showed that the groundwater level in Minqin desert oasis ranged mainly from 15 to 30 m, and the buried depth of groundwater affecting vegetation cover in oasis ranged mainly from 1 to 10 m. The impact of groundwater on vegetation cover decreased with its level dropping. NDVI was consistent with the trend of annual precipitation, both showed increasing trends. Precipitation significantly affected the vegetation cover of oasis surface.

  Risk Analysis and Regionalization of Heat Damage During Heading and Flowering Stage of Mid-season Rice in Hubei Province YE Pei, LIU Kequn, SHEN Shuanghe, LIU Kaiwen, LIU Zhixiong, DENG Yanjun 2022, 38 (8):  110-117.  DOI: 10.11924/j.issn.1000-6850.casb2021-0345 Abstract + ( 444 )   HTML ( 2 )   PDF ( 2401KB )   ( 74 ) To explore the risk variation of heat damage during heading and flowering stage of mid-season rice in Hubei Province, mathematical statistics and correlation analysis methods were used to analyze the response of mid-season rice to heat damage indicators, the interannual variation and spatial distribution of mid-season rice heat damage and the risk regionalization from the perspective of yield components based on data of annual growth period of mid-season rice from 18 agrometeorological observation stations in Hubei, the meteorological data of the province from 1960 to 2019, and the data of field high temperature control experiment in Jingzhou from 2016 to 2017. The results showed that: (1) the negative correlation between ≥35℃ accumulated temperature of heat damage and key yield components (seed setting rate) was a better indicator than the high temperature days; (2) from 1960 to 2019, the intensity of heat damage during heading and flowering stage of mid-season rice in Hubei showed a chronological change of first decrease then increase, especially since the beginning of the 21st century, the heat damage had increased frequency, strengthened intensity, and wider range; spatially, the increase of intensity and frequency was the largest in eastern Hubei, followed by Jianghan Plain and southwest Hubei, and the increase was small in northwest Hubei; (3) the high-risk areas were northwest Hubei, the Three Gorges Valley of the Yangtze River, and east Hubei; the low-risk areas were the middle and high mountains in southwest Hubei and most of the Jianghan Plain; the rest were medium-risk areas. The heat damage risk from 1990 to 2019 was higher than that from 1960 to 1989, intensified significantly.

  Spatial Distribution of Heat Injury of Grape in Guangxi Based on SURFER Technology WU Xuanke, WANG Renjun, HUANG Wei, LIU Yongyu, YAO Yuqun 2022, 38 (8):  118-121.  DOI: 10.11924/j.issn.1000-6850.casb2021-0365 Abstract + ( 280 )   HTML ( 4 )   PDF ( 1460KB )   ( 41 ) Heat injury is the most important agrometeorological disaster affecting grape production in Guangxi. The authors analyzed the occurrence frequency and spatial distribution of grape heat injury in Guangxi, aiming to provide a scientific decision-making basis for optimizing the distribution of grape industry. Based on the meteorological data of 91 national meteorological observation stations from 1961 to 2016, the frequency of heat injury in flowering bearing period (April to May) and mature harvest period (July to August) was calculated according to the index of grape heat injury grade. The spatial distribution characteristic map of heat injury frequency of grape was obtained based on SURFER technology. The results showed that high temperature became the main meteorological factor restricting grape production in Guangxi. According to the spatial distribution map of grape heat injury in mature harvest period, the areas without heat injury, with mild heat injury, moderate heat injury, severe heat injury and serious heat injury were classified in Guangxi. Most of the grape production areas in Guangxi were concentrated in severe and serious heat injury region. Strengthening the measures against heat injury of grape could improve the quality of grape fruits.

  Meteorological Disaster Analysis and Climatic Regionalization for Grape Planting in Guannan, Lianyungang REN Shuxia, HAO Ling, DONG Jingming, HU Dongli, WEI Yikun 2022, 38 (8):  122-128.  DOI: 10.11924/j.issn.1000-6850.casb2021-0319 Abstract + ( 310 )   HTML ( 9 )   PDF ( 1496KB )   ( 212 ) Based on data from 17 observatory stations of Guannan grape planting area in Lianyungang from 2008 to 2017, including the ten-day, monthly and yearly temperature, precipitation and sunshine, we used GIS to convert 1:250000 basic geographical background data of Lianyungang into a high-resolution (100 m×100 m) digital terrain model. By adopting geographic information system and analytic hierarchy process, we combined the climatic conditions with meteorological disasters and preventive measures during the growth period of grape, and obtained the zoning index of grape climate suitability. The results showed that the temperature during the budding period of the grapes in April, and precipitation during flowering period in May, and rainfall value during fruit ripening in August could be selected as the research indexes of climatic suitability, and scored by experts, their weight coefficients were 0.4, 0.4 and 0.2 respectively. These indexes were divided into 3 levels: suitable, sub-suitable and unsuitable, to determine the climatic and ecological conditions for commercial grape cultivation. The results show that the most suitable climatic areas for grape cultivation are in central and northern Guannan, including Zhangdian, Beichenji and Sankou; the sub-suitable areas are Mengxingzhuang, Tanggou and Liji; the unsuitable areas are in southern and eastern Guannan, such as part of Xinji, Xin’an, Huayuan, Bailu, and etc. This research method could provide reference for the safe layout of various cash crops in Lianyungang.

  Effect of Seasonal Variation on Intestinal Microflora of Free-range Luhua Chicken Analyzed by DGGE ZHANG Tengshuai, ZHANG Yanying, LIU Jingguo 2022, 38 (8):  129-134.  DOI: 10.11924/j.issn.1000-6850.casb2021-0237 Abstract + ( 286 )   HTML ( 4 )   PDF ( 1268KB )   ( 123 ) To explore the effect of seasonal variation on the intestinal microflora of adult chicken, the PCR-DGGE method was used in this study to determine the microbial community in caecum and small intestine, which were collected from free-range Luhua chicken in winter, spring and summer. The results showed that the intestinal microflora of adult chicken changed greatly with season. There were only 66.7% and 62.5% similarity between microbial community in caecum and small intestine in summer and those in winter, respectively. The diversity of microbial community in caecum was much higher than that in small intestine. However, seasonal variation had different effects on the microflora of caecum and small intestine. The microflora diversity of caecum was lower in summer and winter than that in spring, while that of small intestine in summer and winter were higher. The common strains in caecum included Megamonas, Bacteroides and Clostridium, whose amount did not change with season; while the common strain in small intestine was mainly Lactobacillus, and the amount of its different species changed with season. These results provide a theoretical basis for adding distinct probiotics to forage according the seasonal variation.

  Recognition of Hemerocallis citrina Leaf Disease Based on PSO and SVM SUN Yu, ZHANG Yongmei, WU Yujun 2022, 38 (8):  135-140.  DOI: 10.11924/j.issn.1000-6850.casb2021-1215 Abstract + ( 214 )   HTML ( 4 )   PDF ( 1577KB )   ( 349 ) By using digital image processing technology, the disease image of Hemerocallis citrina leaf was taken as the recognition object. The disease area was segmented based on Lab space and K-means clustering algorithm, and the color characteristics, histogram of oriented gradient (HOG) and shape characteristics of the target areas were extracted from the images. The single-feature model and multi-feature model were established respectively based on the extracted features. Particle swarm optimization (PSO) algorithm was used to optimize the penalty factor and kernel parameter of the support vector machine (SVM) model through cross validation. Multi-feature classification model based on PSO-SVM was established to identify diseases of H. citrina leaves. The recognition rate of SVM based multi-feature classification model was higher than that of single-feature classification model, and the recognition rate could reach 81.67%. The recognition rate of multi-feature classification model based on PSO-SVM was as high as 92.39%. The multi-feature classification model based on PSO-SVM has high recognition rate and can identify the disease of H. citrina leaf timely, conveniently and efficiently.

  Studies on Fish Resource Development and Utilization in the Middle and Lower Reaches of the Yalu River LI He, LI Wenkuan, ZHAO Xiaolin, WANG Xingbing 2022, 38 (8):  141-146.  DOI: 10.11924/j.issn.1000-6850.casb2021-0097 Abstract + ( 422 )   HTML ( 5 )   PDF ( 1177KB )   ( 424 ) The Yalu River flows through Jilin and Liaoning Province. Because of its special geographical condition, climate environment and fish fauna composition, there are many special economic fish species. In recent years, in order to meet the needs of aquaculture farmers and consumers, a lot of research work has been done on the development and utilization of fish resources in the Yalu River, which has played an important role in promoting the freshwater fishery in Liaoning Province and increasing aquaculture farmers’ income. The paper summarized the characteristics of fish resources in the Yalu River, the development and utilization of the main economic fish resources such as Hypomesus transpacificus, Plecoglossus altivelis, Siniperca scherzeri, Hemibarbus labeo and Odontobutis yaluensis, and the present situation of fish breeding. Some suggestions were put forward, including the investigation of fish resources in the Yalu River, the management of cage culture, the selection of fine species and the development of feed.

  Policy Discussion on Consolidating and Expanding the Effect of Poverty Alleviation by Economic Forest Industry WANG Feng, SHI Hongqing, JIANG Qiumin 2022, 38 (8):  147-151.  DOI: 10.11924/j.issn.1000-6850.casb2021-0389 Abstract + ( 278 )   HTML ( 4 )   PDF ( 1013KB )   ( 37 ) The purpose of the study is to summarize the main achievements of economic forest industry in poverty alleviation, find out the problems and put forward some policy suggestions on how to give play to the important role of economic forest industry in consolidating and expanding the effect of poverty alleviation. We collected and analyzed the data and conducted field research in six counties of Shanxi, Sichuan and Yunnan Province. We notice that the poverty alleviation effect of economic forest industry is remarkable. It has become the main source of farmers’ income, and has promoted the employment of farmers and the beautiful rural construction. However, there are still some prominent problems of the economic forest industry in the areas lifted from poverty, such as inadequate implementation of planning, mixed cultivation varieties, extensive management measures, undeveloped processing and storage industry and insufficient support of science and technology. In response to the problems, suggestions are put forward from the aspects of strengthening macro-guidance to the economic forest industry, enhancing scientific and technological support and technology promotion, expanding the forestry industry policy, improving the level of organization and branding of industrial development and cultivating the circulation system, in order to provide policy reference for better developing the forestry characteristic industry, consolidating and expanding the achievements of poverty alleviation and comprehensively promoting the rural revitalization.

  The Crop Yield Estimation Model Based on Multiple Regression Analysis ZHOU Xiaohong 2022, 38 (8):  152-156.  DOI: 10.11924/j.issn.1000-6850.casb2021-0364 Abstract + ( 509 )   HTML ( 9 )   PDF ( 1340KB )   ( 81 ) Crop yield estimation is related to many aspects, such as grain scheduling, grain market price balance, agricultural structure adjustment and so on. Therefore, combined with multiple regression analysis, this paper constructed a crop yield estimation model. In this model, the author used gray correlation analysis to find the leading factors that affect crop yield, and then used the data of the leading factors as the input to construct the multiple linear regression estimation model of crop yield and get the estimated value of crop yield. The results show that: by using this model to estimate the total yield of maize in the three northeast provinces of China from 2017 to 2019, the error between the predicted yield and the actual yield is less than 1%, indicating that the model has high accuracy and wide application prospect.

  The Coordinated Development of Population and Land Urbanization in Jiangsu Province LI Zipeng, OU Xiangjun, ZHU Jie, ZHOU Beibei, QIAN Jialin, ZHU Huxiao 2022, 38 (8):  157-164.  DOI: 10.11924/j.issn.1000-6850.casb2021-0357 Abstract + ( 370 )   HTML ( 6 )   PDF ( 1572KB )   ( 47 ) By analyzing the coordinated development level of population and land urbanization in Jiangsu Province and its three major regions (the south, central and north Jiangsu), we aim to promote the high-quality development of urbanization. By constructing a population and land urbanization evaluation index system, we used the coefficient of variation method and the entropy method to determine the weights and adopted the coupling coordination degree model to study the coordination of population and land urbanization of Jiangsu Province from 2000 to 2018 and that of 13 prefecture-level cities of the province in 2018. The results showed that: (1) the population urbanization index of Jiangsu Province was slightly higher than that of the land urbanization index from 2000 to 2001 and from 2003 to 2013, which was a lagging type of land urbanization; the land urbanization index of Jiangsu Province was higher than that of the population in 2002 and from 2014 to 2018, the urbanization index belonged to the lagging type of population urbanization; (2) the degree of coordination between population and land urbanization in Jiangsu Province was unbalanced (2000 to 2001), of medium-low coordination (2002 to 2004), of moderate coordination (2005 to 2008), of medium-high coordination (2009 to 2012), and of high coordination (2013 to 2018); (3) the lagging space of population and land urbanization in Jiangsu Province presented a ‘north-south’ structure, the level of urbanization in Jiangsu Province was uneven and the phenomenon of polarization was prominent; (4) except Xuzhou City, the coordination degree of population urbanization and land urbanization in Jiangsu Province showed a ‘step-like distribution down from south to north’, Nanjing City had the highest degree of coordination between population and land urbanization, and Suqian City had the lowest degree of coordination. This study obtained the temporal evolution law and spatial pattern characteristics of the population and land urbanization in Jiangsu Province, and stated the direction for the coordinated development of population and land urbanization in the province.