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• 2023 Vol.39 No.22 Published:05 August 2023

  Effects of Bio-organic Fertilizer on Photosynthetic Characteristics, Dry Matter Accumulation and Transportation and Yield Formation of Continuous Cropping Sugar Beet Under Reduced Chemical Fertilizer Application GUO Xiaoxia, TIAN Lu, JIAN Caiyuan, HUANG Chunyan, LI Zhi, ZHANG Peng, HAN Kang, LIANG Yahui, KONG Dejuan, SU Wenbin 2023, 39 (22):  1-10.  DOI: 10.11924/j.issn.1000-6850.casb2023-0052 Abstract + ( 124 )   HTML ( 6 )   PDF ( 1411KB )   ( 52 ) To study the regulatory effects of bio-organic fertilizer on continuous cropping sugar beet under reduced chemical fertilizer and to screen out the best amount of bio organic fertilizer, conventional fertilization (900 kg/hm2 chemical fertilizer) was used as the control (CK), five bio-organic fertilizer treatments were set up (BOF1: 1500 kg/hm2, BOF2: 3000 kg/hm2, BOF3: 4500 kg/hm2, BOF4: 6000 kg/hm2 and BOF5: 7500 kg/hm2), and on the basis of reducing 300 kg/hm2 chemical fertilizer, the effects of bio-organic fertilizer on the photosynthetic characteristics, dry matter accumulation and distribution, yield and quality formation of continuous cropping sugar beet were studied. The results showed that bio-organic fertilizer could promote the photosynthetic characteristics and dry matter accumulation of continuous cropping sugar beet. Compared with the CK, the BOF1 had no significant effects on photosynthetic characteristics and dry matter accumulation of sugar beet during the whole growth periods. Those of BOF2 showed differently among different index and growth periods. While the effects of BOF3, BOF4 and BOF5 all showed significantly except at seedling growth period. The net photosynthetic rate increased by 6.93%-15.23%, 11.50%-21.67% and 5.53%-16.23%, respectively; the intercellular CO2 concentration increased by 10.14%-16.60%, 14.90%-23.06% and 9.90%-16.23%, respectively; the stomatal conductance increased by 15.35%-22.34%, 23.20%-34.94% and 14.61%-22.80%, respectively; the SPAD value increased by 12.93%-24.03%, 24.30%-30.94% and 12.85%-23.14%, respectively; and the total dry matter accumulation amount increased by 14.29%-25.09%, 23.95%-40.09% and 16.24%-27.10%, respectively. Only BOF4 had positive effects on regulating dry matter distribution except at seedling stage. The distribution rate of leaf significantly decreased by 2.25%-10.19%, and the distribution rate of root significantly increased by 2.24%-7.58%. It could effectively promote the transfer of dry matter from ground to the root tubers of sugar beet. The yield of continuous cropping sugar beet increased first and then decreased with the increase of bio-organic fertilizer application amounts. Except treatment BOF1, other biological organic fertilizer treatments all significantly increased the yield compared with CK. The yield of sugar beet in BOF2, BOF3, BOF4 and BOF5 increased by 5.69%, 11.82%, 22.29% and 11.95%, respectively. Only in BOF3 and BOF4, the sugar yield significantly increased by 8.82% and 17.39% compared with the CK. At the same time, through linear fitting, the maximum beet yield and sugar yield appeared around the application amount of 6000 kg/hm2. Above all, on the basis of reducing chemical fertilizer for 300 kg/hm2, the combination with biological organic fertilizer of 6000 kg/hm2 can increase the yield and quality of continuous cropping sugar beet at the same time.

  A Method of Sugar Free Tissue Culture and Rapid Propagation of Virus-free Potato Seedlings LIU Dan, LIANG Ruiping, LI Xiuhua, WANG Liangming, BAI Yinfeng 2023, 39 (22):  11-15.  DOI: 10.11924/j.issn.1000-6850.casb2023-0074 Abstract + ( 123 )   HTML ( 6 )   PDF ( 1465KB )   ( 48 ) In order to improve the quality of virus-free potato seedlings and optimize potato seedlings production, the application of sugar free culture in rapid propagation of virus-free potato seedlings was studied. The virus-free plantlets of potato early maturing variety ‘Atlantic’ were used as materials. The results showed that after 25 days of sugar free culture, the plant height, internode number, and rootless fresh quality of potato seedlings double stage inoculation were significantly greater than those inoculated in single segment, double stage inoculation was more suitable for rapid propagation of virus-free potato seedlings. The segments of potato virus-free seedlings grew best in a sugar free culture box supported by plastic particles, but the price was relatively expensive. Therefore, it was recommended to use vermiculite as the support for comprehensive consideration. The plant height of potato plantlets injected with CO2 3 days after inoculation was 10.29 cm, significantly higher than that of other treatments. Under the conditions of light intensity of 8000-8500 lx and CO2 concentration of 1×106 mg/m3 sugar-free culture, potato virus-free seedlings had the best growth potential, with a plant height of 10.28 cm, stem diameter of 1.55 cm, and fresh weight of 0.90 g, significantly higher than other treatments.

  Effects of Slow-release Fertilizer Application and Film Mulching on Growth of Cassava WEI Yundong, ZHOU Shiyi, CHEN Ruirui, PAN Huan, LI Jun, HE Cuicui, XU Chuan, ZHENG Hua 2023, 39 (22):  16-22.  DOI: 10.11924/j.issn.1000-6850.casb2022-0681 Abstract + ( 177 )   HTML ( 5 )   PDF ( 1274KB )   ( 23 ) In order to provide scientific basis for the development of special slow-release fertilizer for cassava and improve the benefit of cassava planting, a field trial was conducted in 2021 with 8 treatments, including no fertilization (CK) and conventional fertilization, and other 6 combinations of two slow released fertilizers (C1, single-film slow released fertilizer with small particle; C2, double-film slow released fertilizer with small particle), and two types of mulching, including plastic film mulching (PF) and ground cloth (GC) mulching. Cassava growth and root yield, nutrient absorption and fertilizer utilization were investigated. The results showed that cassava growth such as plant height and stem diameter were stimulated by fertilization, as well as the biomass accumulation and cassava yield. Compared with conventional fertilization, slow-release fertilizer improved the growth of cassava, the root yield increased by 21.29%-53.00%, the starch yield increased by 25.46%-58.1%, and the nutrient utilization rate increased by 1.9%-27.1%; C1 and C2 combined with mulching film/ cloth had better effect on promoting the growth of cassava, increasing cassava yield and fertilizer utilization rate, increasing the yield of fresh root by 37.41%-52.00% and starch by 39.58%-58.1%; compared with conventional fertilization, slow-release fertilizers C1 and C2 reduced the amount of phosphate fertilizer and greatly improved its utilization rate by 14.0%-47.3% while ensuring the yield of cassava. In conclusion, applying C1 and C2 is an effective way to increase cassava growth and root yield, and fertilizer utilization rate, and it is more helpful when combined with plastic film or cloth mulching. The application of C1 with N 100 kg/hm2, P2O5 33.3 kg/hm2 and K2O 100 kg/hm2, together with ground cloth covering is the optimum for cassava in this study.

  Progress of Genome-wide Association Studies in Genetic Improvement of Cucurbitaceae XU Yingchao, LU Sen, ZHANG Sicheng, MENG Qitao, LIN Huijing, XUE Shudan, LIU Hongbiao, GUO Hanquan, FU Manqin, SONG Dongguang, ZHONG Yujuan 2023, 39 (22):  23-33.  DOI: 10.11924/j.issn.1000-6850.casb2022-0697 Abstract + ( 88 )   HTML ( 1 )   PDF ( 1274KB )   ( 21 ) To advance the application of genome-wide association study (GWAS) in the precise mining of the key genetic variation loci associated with important agronomic traits in cucurbit crops, this paper introduced the principles and statistical models of GWAS, outlined the advantages of GWAS in identifying genetic variation loci in crops populations, studying plant metabolic mechanisms and implementing precise genetic improvement strategies. It also systematically reviewed the recent advances of GWAS in the genetic improvement of major cucurbit crops such as watermelon, melon, cucumber, pumpkin or other kinds of cucurbit crops. Furthermore, it provided an outlook on the joint multi-omics analysis and database in breeding research of cucurbit crops, giving a basis and reference in the process of genetic improvement of cucurbit crops.

  Influences of Biogas Slurry Instead of Chemical Fertilizer on Yield and Quality of Radish in Open Field and Soil Physicochemical Properties HAN Xiaofei, LI Xiaoran, WANG Junwei 2023, 39 (22):  34-39.  DOI: 10.11924/j.issn.1000-6850.casb2022-0583 Abstract + ( 93 )   HTML ( 4 )   PDF ( 1151KB )   ( 24 ) The paper aims to explore the optimal amount of alternative chemical fertilizer under the condition of radish biogas slurry returning to field in the hilly-brown soil area of western Henan, and provide scientific theoretical basis for the recycling of biogas slurry. Under field conditions, radish variety ‘Pingfeng 3’ was used as experimental material, and five treatments were set up, including low biogas slurry (22.5 t/hm2, T1), medium biogas slurry (45 t/hm2, T2), high biogas slurry (67.5 t/hm2, T3), conventional fertilization (600 kg/hm2, T4) and no fertilization (0, CK). The effects of biogas slurry replacing chemical fertilizer on the growth, yield and quality of open field radish and soil physicochemical properties were studied. The results showed that biogas slurry had no negative effect on the growth and development of radish, and ensured the yield of radish. The highest yield of T3 treatment was 10.2% higher than that of T4. The root weight, root transverse stem, root length and leaf length of radish were the best in T3 treatment. The soluble solid content, protein and vitamin C content of radish treated with T1, T2 and T3 were significantly higher than those of T4 and CK (P<0.05). After biogas slurry was returned to the field, the soil nutrient content changed compared with that before returning to the field. Compared with T4 treatment, the organic matter and alkali-hydrolyzable nitrogen content in the biogas slurry treatment group were significantly increased (P<0.05), and the highest (T3 treatment) increased by 7.2% and 8.6%, respectively. The available phosphorus decreased, and the pH and total nitrogen, total phosphorus and total potassium changed little. Under the experimental conditions, it is recommended to apply biogas slurry three times during the whole growth period of open field radish, and the total application amount is controlled at 70t/hm2. The application periods are as basal fertilizer (50%) at the early sowing stage, seedling stage (30%) and rosette stage (20%).

  Growth Characteristics and Water Use Efficiency of Tomato and Cucumber Seedlings in Different Facilities WEN Jiangli, GUO Wenzhong, JIAO Youquan, ZHANG Tao, WU Xiaosu 2023, 39 (22):  40-46.  DOI: 10.11924/j.issn.1000-6850.casb2022-0618 Abstract + ( 83 )   HTML ( 1 )   PDF ( 1362KB )   ( 26 ) To explore the effect of different facility environments on vegetable seedlings, with tomato and cucumber plug seedlings in solar greenhouse and plant factory as experimental materials, the research on the growth and water use efficiency of tomato and cucumber seedlings in different facility environments was carried out. The experiment showed that the plant height, stem diameter, leaf area and water consumption of tomato seedlings in solar greenhouse were higher than those in plant factory. There was no significant difference in aboveground dry weight of tomato seedlings under different treatments. The plant height, stem diameter, aboveground dry weight and water consumption of cucumber seedlings in solar greenhouse were higher than those in plant factory. Compared with solar greenhouse, plant factory significantly increased the underground dry weight, strong seedling index and water use efficiency of tomato and cucumber seedlings. It can be seen that plant factory can produce high-quality and strong seedlings while achieving high efficiency and water saving. It is recommended to carry out vegetable seedling cultivation under plant factory conditions.

  Screening of Low Temperature Tolerant Rootstock and Optimization of Grafting System for Pepper LONG Huijun, LI Ziyu, OU Lijun, SUO Huan 2023, 39 (22):  47-51.  DOI: 10.11924/j.issn.1000-6850.casb2022-0640 Abstract + ( 143 )   HTML ( 3 )   PDF ( 1553KB )   ( 21 ) In this paper, we compared the effects of phenotypic difference of different rootstocks, grafting methods and grafting leaf age under low temperature treatment on the survival rate of grafting, aiming to provide a basis for screening low-temperature tolerant rootstocks and optimizing the grafting system of pepper. The results showed that wild eggplant S2 had a high tolerance to low temperature and could be used as a low temperature tolerant rootstock for pepper grafting. The highest survival rate of grafting was achieved by the splitting method when the rootstock was two-leafed and the scion was three-leafed. The results of the study can be a practical basis for improving the low-temperature tolerance of pepper plants in early spring and post-autumn facility cultivation.

  The Nutrition and Benefit Analysis of Volvariella volvacea Cultivated in Field with Straw Substrate XIAO Zitian, HE Huanqing, FU Min, PENG Yangyang, LIU Ming, YANG Qiuming, WEN Yuanming, XU Jiang 2023, 39 (22):  52-58.  DOI: 10.11924/j.issn.1000-6850.casb2022-0588 Abstract + ( 82 )   HTML ( 1 )   PDF ( 1265KB )   ( 18 ) Volvariella volvacea can be produced by straw substrate. In order to improve the utilization rate and benefit of straw wastes, and promote the new high-efficiency cultivation technology, we explored the feasibility of the annual rotation pattern of rice-straw mushroom-vegetable from the perspectives of nutritional evaluation and economic benefit analysis. The straw was collected and used for straw mushroom cultivation, the fruiting-body protein, amino acid, mineral ions and other components of mushroom were detected. The proportion of essential amino acids (EAA), ratio of essential amino acids to WHO/FAO model spectral values (RAA), amino acid ratio coefficient (RC) and amino acid ratio coefficient evaluation score (SRC) were evaluated. Soil organic matter was detected and the economic benefits were calculated. The fresh protein, fat, carbohydrate, potassium and phosphorus were 2.93% (36.63% for dry), 0.3%, 3.8%, 3.05×103 mg/kg, and 1.05×103 mg/kg, respectively. The cultivated mushroom contained 17 kinds of hydrolyzed amino acids, of which essential amino acids accounted for 32%, glutamate content was the highest, and branch chain amino acids accounted for 15.13%. RAA values of six essential amino acids were close to those of WHO/FAO model, and SRC values were 64. Twenty kinds of free amino acids were detected, and sweet and umami amino acids accounted for 44.43%. Glutamic acid was the main umami amino acid. Soil organic matter content increased by 20.33% after fungus residue was returned to the field. Straw mushroom cultivation earnings are eight times that of rice. The pure straw substrate cultivation of Volvariella volvacea has many benefits, such as rich in nutrition, good economic benefit, and improving soil organic matter content by fungus residue, so it is suitable for application in main rice producing areas in south China.

  Effects of Soil Amelioration Methods on Growth and Flowering Quality of Rose ‘Scarlet Bonica’ TANG Jingwen, SHI Zhengjun, XIE Ruixing, LAN Cuiyu, LIU Yiye, WANG Xiaoqing, CAI Jiangqiao 2023, 39 (22):  59-64.  DOI: 10.11924/j.issn.1000-6850.casb2022-0579 Abstract + ( 83 )   HTML ( 2 )   PDF ( 1314KB )   ( 17 ) To study the soil improvement formula for ground cropping of rose ‘Scarlet Bonica’, a new and excellent rose with high humidity and heat resistance, the garden soil, green-waste compost, peat, river sand and superphosphate were mixed into 6 different formulas to improve the planting soil, and the unimproved garden soil was used as the control to observe the effects of different amelioration methods on soil fertility, growth and flowering of rose ‘Scarlet Bonica’. The results showed that soil bulk density was in the range of 0.69-1.10 g/cm3, and soil total porosity was 57.7%-71.2%, soil organic matter was increased by 11.1-37.4 g/kg, and soil nitrogen, phosphorus and potassium nutrient supply capacity was significantly improved. Soil amelioration had significant effects on growth phenology, and prolonged flowering period, improved vegetative growth and flowering quality of rose ‘Scarlet Bonica’. But different amelioration methods had different promoting effects on growth and flowering of the plant. In 6 soil amelioration treatments, the formula of 50% garden soil, 40% green-waste compost, 10% river sand volume ratio is the best for plant crown growth, plant height growth, new branch length, and can achieve good flowering effect.

  Comparative Study on the Growth of 14 Rhododendron spp. in Summer CHEN Rui, XIAN Xiaolin, LI Shifeng 2023, 39 (22):  65-71.  DOI: 10.11924/j.issn.1000-6850.casb2022-0653 Abstract + ( 91 )   HTML ( 1 )   PDF ( 1875KB )   ( 24 ) In order to further improve the introduction and cultivation of Rhododendron, and select suitable varieties for planting in Sichuan basin, growth index of the whole plant (crown width, plant height, ground diameter), branches (longest branch length, single branch thickness, the number of leaf at the longest branch), leaf (leaf length, leaf width, leaf thickness), and summer branches length of 14 introduced new varieties of Rhododendron were evaluated in this comparative study. The results showed that the adaptive growth performances of 14 varieties were different, the crown width and plant height of ‘Prince Lavender’ increased the most, which were 8.40% and 27.79% respectively; the ground diameter of ‘Strawberry Sundae’ increased the most by 20.04%; the longest branch length of ‘Atlas’ increased the most by 11.13%; the single branch thickness, leaf length and leaf width of ‘Mrs. Fujiichi’ increased the most, which were 15.48%, 17.66% and 18.48% respectively; the number of leaf at the longest branch, leaf thickness and summer branches of ‘Purple Rainbow’ increased the most, which were 43.36%、5.98% and 5.98 cm respectively. Four factors were obtained from principal component analysis, and the cumulative variance contribution rate reached 84.560%, the comprehensive scores of ‘Strawberry Sundae’ was relatively high. Collectively, varieties with scores of grade II and above are more suitable for summer growth under sparse forest (semi shading) conditions in Sichuan basin, such as ‘Strawberry Sundae’, ‘Princess Pearl’, ‘Sweetheart’, ‘Atlas’, ‘Mrs. Fujiichi’, and ‘Purple Rainbow’.

  A Morphology Study on Leaf Bud Formation and Flower Bud Differentiation of Daphne giraldii SHI Yaqian, YAN Fang, CHEN Xiaoai, LV Biao, ZHANG Chunyun, WANG Haiping, WANG Jiandong, XU Tao, ZHANG Chunmei, CHEN Ye 2023, 39 (22):  72-76.  DOI: 10.11924/j.issn.1000-6850.casb2023-0161 Abstract + ( 78 )   HTML ( 3 )   PDF ( 1745KB )   ( 20 ) Using paraffin section and anatomical observation techniques, the process of leaf bud and flower bud initiation and flower organ differentiation of Daphne giraldii was studied, and the characteristics of leaf bud growth and flower bud differentiation of D. giraldii were clarified, so as to provide theoretical basis for D. giraldii breeding and systematic classification research. The results showed that: (1) the leaf buds of D. giraldii were distributed at the top and both sides of the old branches, which were divided into terminal buds and leaf buds. The entire leaf bud was conical in shape with scales covering the outside, the top being convex, and unconspicuous stipules. The leaf primordium differentiation period of leaf buds was from mid-late March to mid-April. (2) The flower bud differentiation of D. giraldii could be divided into 7 stages (mid-April to mid-May) including undifferentiated stage, early stage of differentiation, inflorescence primordium differentiation, floret primordium differentiation, petal primordium differentiation, stamen primordium differentiation, and pistil primordium differentiation. (3) A new stem was sprouted from the center of the leaf bud of D. giraldii (mid-April), and the flower bud grew at the apex of the central stem tip of the new stem from the leaf bud. (4) The observation of internal structure showed that the time of new stem emergence and flower bud differentiation of D. giraldii was synchronous.

  Research on Physiological Characteristic of Three Species of Cerasus to Low Temperature Stress LI Huanyong, LIAO Fangzhou, LAN Pu, YANG Lifang 2023, 39 (22):  77-82.  DOI: 10.11924/j.issn.1000-6850.casb2022-0644 Abstract + ( 91 )   HTML ( 2 )   PDF ( 1373KB )   ( 23 ) To study the effects of low temperature stress on Cerasus plants, such as the Tianjin wild Cerasus serrulata and sweet cherry rootstocks, one-year-old branches of three species of Cerasus were used as materials to study the changes of relative conductivity, osmotic adjustment substances and reactive oxygen under different low temperature stresses. The cold resistance of three species of Cerasus was comprehensively evaluated by the subordinate function method. The results showed that with the decrease of treatment temperature, the relative conductivity of branches of three species of Cerasus increased gradually. The contents of soluble sugar and soluble protein and the activities of antioxidant enzymes of three species of Cerasus increased first and then decreased. The contents of proline and MDA increased gradually with the decrease of temperature. Through the comprehensive analysis of subordinate function, the cold resistance order of three species of Cerasus was ‘Mahaleb’ > wild Cerasus serrulata > ‘Gisela 6’. It was found that the three species of Cerasus adapted to the low temperature environment mainly by increasing the synthesis of osmotic adjustment substances and enhancing the activity of antioxidant enzymes, which provided a basic reference for the screening of cold resistant of sweet cherry rootstocks and the utilization of cold resistant germplasm resources of Cerasus species.

  Study on Comprehensive Effects of Shading Cultivation on Yield and Quality of Green Tea in Sichuan Tea Area LI Lanying, LIU Dongna, ZHANG Hui, GAO Yuan, WANG Yingchun, GONG Xuejiao, LUO Fan 2023, 39 (22):  83-90.  DOI: 10.11924/j.issn.1000-6850.casb2022-0645 Abstract + ( 85 )   HTML ( 1 )   PDF ( 1803KB )   ( 31 ) Shading cultivation was designed and implemented in this research to study the effects of shading cultivation on the yield and its impact on quality of green tea in Sichuan tea area according to the unique geographical and climatic conditions of Sichuan. The study shows that shading cultivation in Sichuan tea area can effectively shorten the growth period of new shoots of tea trees. ‘Fudingdabai’ was shortened by 7 days on average and ‘Sanhua 1951’ was shortened by 3 days on average, which was conducive to increasing the picking rounds of fresh leaves in early spring and then increasing the yield. Shading treatment reduces the growth length of new shoots, which is conducive to the shaping of some tea products. ‘Fudingdabai’ was shaded in one bud and two leaves stage, and the length of new shoots was shortened by 26.62%. In one bud and three leaves stage, the length of new shoots was shortened by 23.36%. ‘Sanhua 1951’ was shaded in one bud and three leaves stage, and the length of new shoots was shortened by 31.32%. Shading is beneficial to the accumulation of free amino acids in tea plants. The content of free amino acids in ‘Fudingdabai’ under shading cultivation was significantly higher than that without shading, and the content of free amino acids in ‘Sanhua 1951’ under shading cultivation was significantly higher than that without shading. Shading is conducive to the accumulation of simple catechins in tea plants. After shading cultivation, the catechin astringent index of ‘Fudingdabai’ and ‘Sanhua 1951’ decreased by 17.99% and 12.27%, which had an important contribution to the ‘fresh’ sensory quality of green tea at the end of spring. It is generally believed that shading cultivation in Sichuan tea area can increase the harvest rounds of spring tea and quality of end spring tea, which is beneficial to improving the comprehensive output value of tea garden.

  Resource and Floristic Characteristics of National Key Protected Wild Plants in Bailongjiang Basin of Gansu ZHAO Huanxin, ZHANG Jiqiang, CHE Zongju, TAN Yanrong, LIU Shizeng, CHEN Wenye, LIN Lin 2023, 39 (22):  91-95.  DOI: 10.11924/j.issn.1000-6850.casb2022-0703 Abstract + ( 115 )   HTML ( 1 )   PDF ( 1267KB )   ( 17 ) In order to understand the resources and floristic characteristics of national key protected wild plants in Bailongjiang basin, we surveyed wild plant resources in the study area by field measurement method and typical sampling method. The research data was analyzed combining with literature review. The results show that: (1) there are 19 national key protected plants, which belong to 15 families and 18 genera, including 3 species of the national protection category I and 16 species of the national protection category II; (2) the national key protected wild plants have no concentrated distribution in the study area and mainly scatter in the lower and middle reaches of the basin, accounting for 95% and 74% of the total national key protection wild plants of the this area, respectively; (3) the floristic characteristics of the wild plants in Bailongjiang basin are complex and diverse, and the floristic geography of plant family and genera can basically be divided into 6 distribution types. This study indicates that the floristic geography of wild plants in Bailongjiang basin is mainly temperate, showing a transition from tropical zone to warm temperate zone, and has abundant unique Chinese components. Most species have narrow distribution range, rare populations and special habitat requirements, which are not conducive to the diffusion and reproduction of plant populations.

  Regional Classification of Flue-cured Tobacco Quality Characteristics in Huili Tobacco Area YUAN Wenbin, HUANG Hao, GUAN Luohao, LI Chao, WANG Wenhui, XIE Danfeng, YANG Tianxu, WANG Wei 2023, 39 (22):  96-103.  DOI: 10.11924/j.issn.1000-6850.casb2022-0668 Abstract + ( 89 )   HTML ( 1 )   PDF ( 2851KB )   ( 14 ) In order to distinguish the quality characteristics of flue-cured tobacco in different micro-ecological zones of Huili tobacco area, C3F grade tobacco leaves from 30 tobacco planting villages were selected. Membership function was used to standardize the raw data of 28 chemical components, coordination, sensory evaluation and appearance quality indicators of flue-cured tobacco, and principal component analysis and cluster analysis were used to establish a comprehensive quality evaluation model for flue-cured tobacco. Finally, the regional difference of flue-cured tobacco quality was visually represented by inverse distance weight (IDW). The results showed that the contribution rate of six principal components reached 82.259%, which could basically reflect all the information of the 28 chemical components. At the square Euclidean distance of 4.0, all samples could be divided into 4 categories, and the comprehensive evaluation score of the 4 categories of flue-cured tobacco was 2.070, 1.731, 1.459 and 0.950, respectively. The regional difference of flue-cured tobacco comprehensive quality index was obvious, and the overall spatial distribution showed a decreasing trend from northwest to southeast. The regional distribution characteristics of tobacco leaf quality in Huili were clarified. The study will provide reference for the production layout planning and the rational utilization of tobacco raw materials.

  Optimization of Fermentation Conditions for Waste Fungus Residue LIU Qi, ZHANG Jingyu, WANG Sheng, ZHANG Naiming 2023, 39 (22):  104-109.  DOI: 10.11924/j.issn.1000-6850.casb2022-0596 Abstract + ( 91 )   HTML ( 2 )   PDF ( 1251KB )   ( 24 ) The paper aims to realize the resource utilization of waste fungus residue, and to explore the suitable fermentation conditions for different waste fungus residue formulas into seedling substrate. In this study, the waste fungus residue of Pleurotus eryngii was used as the main raw material. Under the condition of adding as little supplementary materials as possible, the spoilage degree of waste fungus residue was determined by temperature, moisture content, pH value, EC value, germination index and nutrient indexes before and after fermentation. The main results were as follows. (1) At the end of fermentation, the five formulas all met the standard of seedling substrate (moisture content ≤35%), and the seed germination index was higher than 85%, so the formulas could be used as seedling substrates. (2) The initial fermentation conditions for waste fungus residue as vegetable seedling substrate were as follows: the moisture content was controlled at about 60%, and the C/N ratio was adjusted to about 25:1. (3) Among the five formulas, pure fungus residue fermentation formula without external nitrogen source and fermentation formula with urea had the best fermentation result and were better in line with the principle of cost saving.

  Irrigation Water Quality in Vegetable Planting Parks of Shaanxi Province: Survey and Analysis JIANG Liyuan, ZHAO Wei, YANG Yuanyuan, ZHANG Kai, YANG Zhaosen, CHEN Zhijie 2023, 39 (22):  110-114.  DOI: 10.11924/j.issn.1000-6850.casb2022-0654 Abstract + ( 89 )   HTML ( 1 )   PDF ( 1514KB )   ( 23 ) By taking the irrigation water in main planting parks of facility vegetables in Shaanxi Province as the research object, we conducted an analysis on the electrical conductivity (EC), pH and the composition of main cations and anions (Na+, K+, Ca2+, Mg2+, Cl-, SO42- and NO3-) of irrigation water. The results showed that the average EC value of irrigation water in main vegetable planting parks in Shaanxi Province was 1.07 dS/m, and the EC value of irrigation water in Xianyang, Xi’an and Weinan in the central and eastern regions of Guanzhong as well as Dingbian and Wuqi in northern Shaanxi were relatively high. The EC value of irrigation water in some sampling points in Pucheng, Dali and Wuqi was in a range of 2.4-3.9 dS/m, and the EC value of irrigation water in southern Shaanxi and the west of Guanzhong were relatively low, mostly at 0-0.6 dS/m. The average pH of irrigation water was pH 7.36, which met the requirements of farmland irrigation water quality standard. There was a significant correlation between the total salt content and electrical conductivity of irrigation water, and the correlation coefficient was 0.927. The total salt content of irrigation water exceeded 1000 mg/L (1.35 dS/m) in 40.6% of the planting parks in Xianyang, Xi’an and Weinan in the central and eastern regions of Guanzhong. The concentration order of main cations in irrigation water was Na+>Mg2+>Ca2+>K+, in which Na+ accounted for 62% of the total measured cations, with an average value of 254.6 mg/L; and the concentration order of anions was SO42->Cl->NO3->SO42-, in which SO42- accounted for 63% of the total measured anions, with an average value of 454.99 mg/L. The EC value of irrigation water was significantly correlated with Na+, K+, Mg2+, Cl- and SO42-. In summary, the salt content of irrigation water in the central and eastern regions of Guanzhong is high, and the main ion components are Na+, K+, Mg2+, Cl- and SO42-. It is suggested to select appropriate vegetable varieties according to the irrigation water quality of the planting park.

  Temporal and Spatial Distribution of Low Temperature and Continuous Rain During Rice Transplanting to Tillering Stage in Sichuan Province LIU Ruolan, YUAN Shujie, RUAN Dichen, HAN Lin, SHI Hongxia 2023, 39 (22):  115-123.  DOI: 10.11924/j.issn.1000-6850.casb2022-0648 Abstract + ( 102 )   HTML ( 2 )   PDF ( 7065KB )   ( 31 ) To provide a scientific basis for rice protection against low temperature and continuous rain in Sichuan during different fertility periods, this paper divided Sichuan into six sub-regions based on topographic and climatic characteristics. The study took records of 91 meteorological stations from 1961 to 2020 as the analysis data, and used the linear propensity estimation method and low temperature and continuous rain disaster indicators, to calculate the frequency of disasters, disaster index, and climate propensity rate, and analyze the spatial and temporal distribution characteristics of low temperature and continuous rain disasters. The results are as follows. (1) The frequency of mild, moderate and severe low temperature disasters during the transplanting and tillering stage of rice in Sichuan was 0.38%-27.5%, 0%-57.6% and 0%-75.3%, respectively. Although the frequency of mild low temperature disaster was small, it covered the widest area, followed by moderate low temperature disaster, mainly in the mountainous area of southwest Sichuan, and the high frequency of severe low temperature disaster was only observed in Guang’an and Longchang. (2) The frequency of light, medium and heavy continuous rain disaster was 8.8%-25.5%, 1.4%-8.0% and 0%-11.2% respectively, the frequency of light, medium and heavy continuous rain disaster had a decreasing trend, and the frequency of medium and heavy disasters were the highest in the northern part of the mountainous area in southwest Sichuan. (3) The frequency of low temperature and continuous rain disaster was 0%-26.1%. Low temperature and continuous rain disaster was in the northern part of the mountainous area of southwest Sichuan, the hilly area of southern Sichuan basin, and the mountainous area of Sichuan basin edge. (4) There were 23 stations recorded significantly interannual variations in the number of days of low-temperature and continuous rain disaster from 1961 to 2020. The number of disaster days per decade decreased in the southern part of mountainous area of southwest Sichuan, the mountainous area of Sichuan basin edge, and the shallow hills of central Sichuan basin, while the number of disaster days increased in the remaining areas. The low-temperature and continuous rain disaster in Sichuan decreased in most areas of the province in recent years in rice transplanting to tillering stage, except some stations in the hilly areas in the south of Sichuan basin and the parallel ridge and valley areas of the east of the basin.

  Temperature and Humidity Difference of Late-maturing Citrus Orchards in Winter ZHOU Shangling, HE Fa, ZHANG Ji, CHEN Pinwen, PU Chengwei, ZHOU Li, YANG Guichuan, DU Xiaoqiu 2023, 39 (22):  124-131.  DOI: 10.11924/j.issn.1000-6850.casb2022-0600 Abstract + ( 91 )   HTML ( 1 )   PDF ( 1415KB )   ( 34 ) The study aims to find out the difference and relationship between the orchard temperature and meteorological temperature of late-maturing citrus in Nanchong of Sichuan Province in winter, as well as the change and difference of temperature and humidity in small area under different weather conditions and cold prevention measures, and lay a foundation for exploring and summarizing suitable, efficient and safe overwintering technology of late-maturing citrus in Nanchong. In this study, a systematic field-test was carried out for the first time in Nanchong, which used common plastic film, cold-proof cloth, single-layer fruit bag, double-layer fruit bag with white outside and yellow inside to conduct comparative experiments. The temperature and humidity changes of each treatment under different weather conditions were monitored, and the orchard temperature and corresponding meteorological temperature were observed and compared. It was found that the orchard temperature and meteorological temperature had discrepancy under different weather conditions. When the meteorological temperature was high, especially at noon on a sunny day, the orchard temperature would be higher than the meteorological temperature, and when the meteorological temperature was low, such as under frost, rain and snow, the orchard temperature would be lower than the meteorological temperature. Through the linear regression analysis of the orchard temperature and meteorological temperature, the relationship expressions of Jialing (T1) and Xichong (T2) test points were T1=1.458TQ-3.114(R2=0.931) (TQ stands for meteorological temperature) and T2=1.379TQ-2.293(R2=0.909), respectively. That was, when the meteorological temperature was about 0.76℃ and 0.21℃ in the two test points respectively, the orchard temperature would reach -2℃, and citrus fruits would suffer from freezing damage. Under different cold protection measures and different weather conditions, common plastic film and cold-proof cloth had the best effect on maintaining and improving orchard temperature. Cold-proof cloth could also significantly reduce the number of days of low temperature and the duration of low temperature, at the same time, no matter what kind of weather conditions, the variation range of humidity in cold-proof cloth treatment was the smallest, and the internal environment was relatively stable. According to the results of this study, cold-proof cloth is the best choice for winter routine protection of late-maturing citrus in Nanchong, and it is very important to establish a linear relationship model between orchard temperature and meteorological temperature for late-maturing citrus to overwinter.

  The Influence of Meteorological Factors on Mature Period of Stipa Herbage in Alpine Grassland ZHANG Xiaoyun, KONG Xiangping 2023, 39 (22):  132-137.  DOI: 10.11924/j.issn.1000-6850.casb2022-0607 Abstract + ( 88 )   HTML ( 2 )   PDF ( 1205KB )   ( 27 ) To explore the characteristics of forage mature period and their influencing factors in alpine grassland, and provide a scientific basis for the determination of local forage maturity, based on the phenological period data of the mature period of alpine grassland and the corresponding meteorological data observed by Xinghai County Meteorological Bureau in Sanjiangyuan region from 1999 to 2021, this paper analyzed the change trend of the mature period of alpine grassland and its main influencing meteorological factors, and built the forecast model of the mature period of herbage. (1) The average temperature in the mature period of Stipa herbage showed a weak trend of decrease, while the precipitation showed a very significant trend of increase in Xinghai County of Sanjiangyuan region from 1999 to 2021. (2) From 1999 to 2021, the mature period of herbage in Xinghai County showed a non-significant early-trend. The mature period of herbage varied greatly from year to year, and the difference between the earliest and the latest was 36 d. (3) The correlation analysis showed that sunshine duration in the middle of April, mean temperature and mean maximum temperature in the middle of May, mean maximum temperature in early June, mean temperature and mean maximum temperature in late July had significantly negative correlations with the mature period of herbage. (4) The regression analysis showed that, when the mean maximum temperature in early June and late July increased (decreased) by 1.0℃, and the sunshine duration increased (decreased) by 10 hours in the middle of April, the maturity of herbage was earlier (or delayed) by 1.6, 2.0 and 1.7 days, respectively. The established forecast model can provide a theoretical basis for the timely and accurate forecast of the mature period of natural pasture forage in the Sanjiangyuan region.

  Effects of Water Control Depth on Herbicide Control in Soil Treatment and Tillering of ‘Yongyou 1540’ Rice at Seedling Stage SHI Jun, LIN Lezhi, CHEN Hongyu, CHAI Weigang, CHEN Jianghua 2023, 39 (22):  138-143.  DOI: 10.11924/j.issn.1000-6850.casb2023-0157 Abstract + ( 82 )   HTML ( 1 )   PDF ( 1299KB )   ( 22 ) To explore the effect of controlled water depth on weed control of soil-applied herbicides and its impact on tillering during the seedling stage of hybrid rice cultivar ‘Yongyou 1540’, this study used ‘Yongyou 1540’ as the test rice, 30% butachlor-propargyl emulsion as the test agent, and conducted greenhouse and field experiments. In both experiments, the treatments were arranged with controlled water depths (1-9 cm) and with or without herbicide application to investigate changes in weed occurrence, rice tillering, and herbicide efficacy between 16-31 days after weed sowing under greenhouse conditions and after rice transplanting under field conditions. The greenhouse experiment showed that the deeper the water depth, the lower the weed occurrence, but there was no significant reduction when the water depth exceeded 5 cm. The field experiment showed that as the water depth increased, tiller numbers first increased and then decreased; the maximum tiller number appeared at the water depth of 5 cm. Under herbicide application, weed occurrence continued to decrease from 16-21 days after transplanting as water depth increased. At 26 to 31 days, the occurrence was the smallest at a water control depth of 5 cm, and increased with the increase or decrease of water depth. Without herbicide application, weed occurrence decreased as water depth increased. Moreover, herbicide efficacy was highest at the water depth of 5 cm, and decreased when water depth increased or decreased. This study clearly demonstrated that using controlled water depth at 5 cm with soil-applied herbicide can maximize the combined effect of controlling weed occurrence, weed eradication, and improving the tillering of ‘Yongyou 1540’. These results provide theoretical support for water management in ‘Yongyou 1540’ rice varieties.

  Advances in Biocontrol Microbes of Potato Late Blight WEI Peixia, FU Haiyan, ZHOU Shuang, LIU Chunguang, WU Tong, YANG Fengshan 2023, 39 (22):  144-151.  DOI: 10.11924/j.issn.1000-6850.casb2022-0823 Abstract + ( 98 )   HTML ( 3 )   PDF ( 1219KB )   ( 31 ) Phytophthora infestans, which causes potato late blight, is one of the most destructive pathogens in potato production. Biocontrol agent (BCAs) as an alternative to chemical fungicides to control potato late blight is one of the important measures to ensure the sustainable development of potato production. In this paper, the research situation and characteristics of potato late blight were briefly reviewed, and the current researches of biocontrol microbes against potato late blight were summarized. The species, source, control effect, antibacterial active substances and action mechanism of the biocontrol microbes for P. infestans were systematically summarized from three levels of bacteria, fungi and actinomycetes. The challenges and limitations of the development and application of biocontrol agents were analyzed. It was suggested that the future biological control of potato late blight should be further studied in four aspects: strengthening the defense function of potato, establishing the prediction model of late blight, paying attention to the population dynamics of biocontrol microorganisms and revealing the control mechanism of P. infestans. The aim is to provide reference for the development and application of biocontrol agents against potato late blight, and sustainable development of potato green industry.

  Multi-angle Volume Detection and Grading of ‘Cuiguan’ Pear Based on OpenCV LIU Xian, CHEN Junsheng, ZHAO Yuhui 2023, 39 (22):  152-157.  DOI: 10.11924/j.issn.1000-6850.casb2023-0212 Abstract + ( 77 )   HTML ( 1 )   PDF ( 1734KB )   ( 14 ) In order to improve the intelligence and efficiency of ‘Cuiguan’ pear size detection and grading, the research on ‘Cuiguan’ pear size detection and grading was conducted based on OpenCV machine vision technology from multiple perspectives. On the self-developed image acquisition system test platform, 100 images of ‘Cuiguan’ pear were collected from multiple angles as test samples. Based on the images, Python language and OpenCV computer vision library programming were used to solve the pixel values of the single angle size of ‘Cuiguan’ pear. Then the fruit size pixel values were calculated from multiple angles. To verify the effect of grading, ‘Cuiguan’ pear were graded according to the local standards of Fujian Province and compared with the traditional weight grading method. The test results show that using machine vision technology to detect and grade the fruit size from multiple angles based on the ‘Cuiguan’ pear image is an intelligent grading method with certain feasibility, reaching a grading accuracy of 97%. The research results can provide technical reference for the size grading method of ‘Cuiguan’ pear based on machine vision.

  Faster R-CNN Detection Method for Citrus Pests Based on Dilated Convolution and Feature Pyramid CEN Xiao 2023, 39 (22):  158-164.  DOI: 10.11924/j.issn.1000-6850.casb2023-0194 Abstract + ( 83 )   HTML ( 2 )   PDF ( 1992KB )   ( 17 ) The four common pests in the citrus planting process were analyzed, and the detection problems of the pests with different sizes and low contrast features were improved on the basis of the Faster R-CNN model. Aiming at the problem that the down-sampling of the pooling layer leads to a decrease in the resolution of the detected image, which in turn leads to the loss of feature information in the image, the hole convolution method is used to capture more deep-level features in the image and increase the receptive field. Combined with the feature pyramid network FPN to fuse the features of different scales in the data, enhance the robustness of the features, and solve the problem that the original RPN network only uses a single final output layer for detection, and the detection accuracy is low. Compared with the original Faster R-CNN model, YOLOv4 and other classic target detection models, the mAP of the improved scheme is 91.72%, and the detection accuracy is improved. The experimental results prove that the proposed improvement scheme can meet the demand of identifying citrus pests in natural environments.