Current issue

• 2020 Vol.36 No.4 Published:05 February 2020

  Effect of Annual Straw Returning Amount on Growth and Yield of Double Cropping Rice in South China Hu Mingfang, Zhao Zhenyong, Zhang Ke 2020, 36 (4):  1-6.  DOI: 10.11924/j.issn.1000-6850.casb18100010 Abstract + ( 497 )   HTML ( 0 )   PDF ( 1242KB )   ( 141 ) To explore the straw returning amount suitable for high and stable yield of double cropping rice in South China, the effects of rice straw returning amount on tiller number, plant weight, dry matter accumulation and early and late rice yield were studied through a 2 years (2016 to 2017) field experiment. 5 different ratios of straw returning were set up in the experiment: no straw addition (CK), 25% straws returning (S1), 50% straws returning (S2), 75% straws returning (S3) and 100% straws returning (S4). The results showed that 100% straws returning inhibited early rice tillering and promoted late rice tillering; 25%, 50% and 75% straws returning treatments had no significant effect on early and late rice in early growth period, but showed positive effect at the middle and late growth stages. The late rice plant height of 75% and 100% straw returning treatments were significantly higher than that of no straw addition treatment, with the average increase of 8.15 cm. Compared with no straw addition, the dry matter accumulation of early and late rice under all straw returning treatment increased, and the difference of 50% straw returning treatment in early rice was significant (P<0.05), which was 8.0% higher than that of CK; 50%, 75% and 100% straw returning treatments averagely increased the dry matter accumulation by 13.3%, and the difference was significant (P>0.05); however, no difference of dry matter accumulation was observed between different amounts of straw returning. Both the yield of early and late rice in straw returning treatments were higher than that of CK, among them, 50% straws returning treatment had the highest early rice yield, with the increase of 6.92%; for late rice, 50%, 75% and 100% straw returning treatments increased the yield by 5.33%, 7.50% and 8.23%, respectively; however, no difference was observed between different amounts of straw returning treatments in both early and late rice. Under this experiment, rerunning 50% straw is the best for increasing early rice yield while 100% is the best for late rice in short time. The long-term effect of straw returning on rice yield needs to be further explored.

  Nitrogen Fertilizer Level: Effects on Yield and Nitrogen Utilization of Strong Gluten Wheat Bai Hui, Zhang Xiu, Chu Jinpeng, Yu Haitao, Yang Hongye, Xu Chenchen, Dai Xinglong 2020, 36 (4):  7-14.  DOI: 10.11924/j.issn.1000-6850.casb18090100 Abstract + ( 561 )   HTML ( 0 )   PDF ( 1270KB )   ( 137 ) To clarify the optimal nitrogen fertilizer application which could simultaneously achieve high grain yield and high nitrogen use efficiency (NUE), the two winter wheat cultivars with strong gluten, ‘Jimai 20’ and ‘Zhouyuan 9369’, were used as materials. Five nitrogen levels included 0, 120, 180, 240, 300 kg N/hm 2 were set. The dry matter accumulation and nitrogen content were measured through drying method and Kjeldahl method, and the relevant NUE indices were calculated subsequently. The results showed that with the increase of the nitrogen input, the yield increased first and then declined. ‘Jimai 20’ had the highest yield at N180 (7.28 t/hm 2) and N240 (7.26 t/hm 2), mainly due to the balanced yield components and higher dry matter accumulation (averaged at 18.54 t/hm 2). While ‘Zhouyuan 9369’ reached the highest yield (7.75 t/hm 2) at N180, mainly resulting from higher spikes per unit area (970.65×10 4/hm 2), kernels per spike (30.83 kernels/spike), dry matter accumulation (20.77 t/hm 2) and harvest index (37.33%). Although the PFPN markedly reduced along with the improved nitrogen level, the REN, AEN and PEN reached the highest value (62.67%, 5.71 kg/kg, 9.11 kg/kg for ‘Jimai 20’ and 63.65%, 7.33 kg/kg, 11.55 kg/kg for ‘Zhouyuan 9369’, respectively) under the condition of N180 level. In terms of the grain yield and NUE, the suitable nitrogen level which could simultaneously achieve high grain yield and high NUE is 180 kg N/hm 2 in the region.

  Effects of Urea Types and Irrigation Management on Water and Fertilizer Conservation in Maize Production Fu Min, Ding Wenchao, Hu Hengyu, Wei Anpei 2020, 36 (4):  15-22.  DOI: 10.11924/j.issn.1000-6850.casb18100083 Abstract + ( 483 )   HTML ( 0 )   PDF ( 1297KB )   ( 91 ) Water and nitrogen management plays an important role in improving crop yield. We studied the effect of urea type and irrigation management on water saving and fertilizer preservation in maize to achieve the goal of high nitrogen fertilizer utilization efficiency and high yield in field production. In 2016 to 2017, we carried out a two-year completely randomized block design experiment to discuss the effects of urea type (common urea and controlled release urea) and irrigation on soil and nitrogen utilization of maize. Two nitrogen levels were set for each urea type, 75 and 150 kg N/hm 2 respectively, with no nitrogen application as the control. Water was set at two irrigation levels, namely, no irrigation during the whole growth period and 85 mm irrigation during the grouting period. The results showed that under the same irrigation and nitrogen application level, the nitrogen content of controlled release urea treatment was higher in soil layer of 0-40 cm, but the nitrogen content in deeper soil layer was lower than that in common urea treatment. Compared with no irrigation, irrigation increased nitrate nitrogen loss, but the loss of nitrate nitrogen in the treatment with controlled release urea was lower than that in the treatment with ordinary urea treatment. The application of controlled-release urea under irrigation conditions could improve the nitrogen absorption of maize and make more nitrogen transfer into grain. Compared with common urea, controlled-release urea improved the nitrogen utilization rate and reduced the dependence of soil on nitrogen demand. Controlled release of urea with low nitrogen could reduce the retention time of nitrate nitrogen in soil and absorbed by maize quickly, thus reducing the risk of nitrate nitrogen loss and improving the efficiency of nitrogen fertilizer utilization in soil. To sum up, the combination of controlled-release urea and a small amount of irrigation was suitable for high nitrogen use efficiency of maize and the production target of high yield field in semi-humid areas in north China.

  Planting Densities Affect the Yield and Canopy Characteristics of Different Summer Maize Plant Types Zhang Hui, Qian Xin, Gao Yingbo, Xue Yanfang, Wang Qingcheng, Liu Kaichang, Li Zongxin 2020, 36 (4):  23-29.  DOI: 10.11924/j.issn.1000-6850.casb18100064 Abstract + ( 603 )   HTML ( 1 )   PDF ( 1390KB )   ( 134 ) The aim is to guide the field production of different summer maize plant types. The horizontal variety ‘Ludan981’ and compact variety ‘Ludan818’ were selected as the test materials, three different planting densities (D1, 30000 plant/hm 2; D2, 60000 plant/hm 2; D3, 90000 plant/hm 2) were set up, the effects of planting densities on the yield, leaf area duration (LAD), leaf area index (LAI), and net assimilation rate (NAR) of different summer maize plant types were studied. The results showed that the yield of ‘Ludan981’ and ‘Ludan818’ was the highest at D2 (11452 kg/hm 2) and D3 (13024 kg/hm 2), respectively. Under D3, compact variety ‘Ludan818’ had a higher LAD [452 (m 2·d)/m 2] and proportion after flowering (50%), ear LAI and NAR during whole growth period [6.87 g/(m 2·d)]. The above results indicate that compact variety has a more compact canopy, leaves in the middle and lower layers intercept more light, which could extend the LAD and contribute to the dry matter accumulation and yield increase. Thus, the variety is more suitable for high density cultivation.

  Sowing Date Affects Grain Filling Progress of Maize in Hetao Area Kong Deyin, Yang Song, Tao Jianguang, Liu Wei, Liu Yanli 2020, 36 (4):  30-35.  DOI: 10.11924/j.issn.1000-6850.casb18100124 Abstract + ( 453 )   HTML ( 0 )   PDF ( 1210KB )   ( 84 ) To cultivate high yield maize, based on the experimental data of sowing by stages, 28 growth models of maize were established (all Logistic equations passed the extremely significant test of 0.01). The growth periods of 100-kernel weight and 100-kernel volume increasing along with the grain filling days were divided into three stages, namely the gradual-increase period, the rapid-increase period and the slight-increase period. In the timely sowing maize, 100-kernel volume and 100-kernel weight entered gradual-increase period after silking, and the ending day was the 6 th day and the 20 th day, respectively; and then they entered the rapid-increase period, the ending day was the 22 nd day and the 18 th day, respectively; after that, the grain volume and weight entered the slight-increase period. The gradual-increase period of 100-kernel weight of timely sowing maize was in the active accumulated temperature interval of 0-502.4℃·d after silking, increased by 0.014 g/℃·d; the rapid-increase period was in the active accumulated temperature interval of 502.4-938.4℃·d after silking, increased by 0.049 g/℃·d; slight-increase period was in the active accumulated temperature interval of 938.4-1355.1℃·d after silking, increased by 0.018 g/℃·d.

  The Effects of Long-term Positioning Fertilizer on Yield, Water and Fertilizer Use Efficiency of Rotation Potato Zhang Jun, Pan Zhihua, Duan Yu, Zhao Peiyi, Wang Bo, Li Huanchun, Lian Haifei 2020, 36 (4):  36-43.  DOI: 10.11924/j.issn.1000-6850.casb18110011 Abstract + ( 642 )   HTML ( 1 )   PDF ( 1292KB )   ( 98 ) To reveal the effects of long-term fertilization on the chestnut soil in the north Yinshan area, potato yield, nutrient absorption, water and fertilizer use efficiency were studied based on the long-term positioning experiment in the Wuchuan, Inner Mongolia. Results showed that LAI, biomass and fertilizer absorption could be significantly enhanced under the combined use of chemical and organic fertilizer (NPK+O) or balanced fertilization (NPK). The maximum LAI and biomass were 2.19 and 136.53 g/plant. The maximum amount of absorption of N, P and K was 3.35, 0.36 and 6.99 g/plant, respectively. Combined use of chemical and organic fertilizer (NPK+O) and balanced fertilization (NPK) could also enhance the potato yield, water use efficiency and fertilizer use efficiency. Potato yield could be increased by 110.57% and 85.44% compared with potato planted without fertilization of NPK+O and NPK. Under the condition of NPK+O and NPK, the commercial yield could be enhanced by 295.11% and 247.56%, the commercial rate was raised by 25 percentage point. Water use efficiency could be enhanced to 42.98、38.27 kg/(hm 2·mm), 107.42% and 38.27% higher than that of the control. The use efficiency of N, P2O5 and K2O was 25.44%, 20.78% and 61.13%, respectively. Producing 1 t potato needed to uptake 3.79-6.41 kg N, 1.28-1.80 kg P2O5 and 5.44-11.70 kg K2O, and the average value was 5.29, 1.61 and 7.99 kg, respectively. The study could provide a basis for optimizing the fertilization of rainfed potato in the north Yinshan area.

  Influence of NPK Combinations on Agronomic Characters, Yield and Nutrition Quality of Potato Wang Xiaoying, Chen Zhanfei, Fang Yuchuan, Lv Jun, Wang Kui, Gao Qingqing, Zhang Yuan 2020, 36 (4):  44-49.  DOI: 10.11924/j.issn.1000-6850.casb20190800573 Abstract + ( 602 )   HTML ( 3 )   PDF ( 1252KB )   ( 116 ) To determine the optimum NPK fertilization rate of potato in Yulin sandy area of Shaanxi Province, field experiments were conducted to study the effects of NPK rates on agronomic characters, yield and nutrition quality of ‘Jizhangshu No.8’ potato. The results showed that various NPK combinations had significant differences on plant height, tuber weight per plant and commodity rate, meanwhile there was no significant difference in the number of tubers per plant. With the increase of nitrogen fertilizer, the yield increased first and then decreased; and with the increase of phosphate fertilizer and potassium fertilizer, the yield change was not obvious. The variation of protein, Vc and reducing sugar were 1.02%-1.69%, 11.49-16.44 mg/100 g and 0.40%-0.84%, respectively, among different treatments. The reasonable NPK fertilizer application rate could improve the growth, yield and quality of potato, and the recommended fertilization is manure 30 t/hm 2, N 150 kg/hm 2, P2O5 90 kg/hm 2, K2O 112.5 kg/hm 2 in Yulin sandy area of Shaanxi with moderate fertility.

  Main Agronomic Traits of Spring Cabbage Breeding Materials: Principal Component Analysis and Cluster Analysis Jiang Kaixuan, Zhao Lejie, Li Jiangli, Wang Chao 2020, 36 (4):  50-55.  DOI: 10.11924/j.issn.1000-6850.casb18100039 Abstract + ( 654 )   HTML ( 2 )   PDF ( 1054KB )   ( 91 ) To provide a basis for the target trait improvement of spring cabbage, the variation analysis, correlation analysis, principal component analysis and cluster analysis were conducted based on 9 agronomic characters of 10 spring cabbage breeding materials. The results showed that the variation coefficient of core length was the highest and the ball width was the lowest. The correlation between the core length and the other 8 agronomic traits was as follows: plant height > head length > length of outer leaf > plant breadth > width of outer leaf > head weight >head diameter>number of outer leaf. The accumulation contribution rate of the top four principal components was up to 93.76%. Cluster analysis divided 10 breeding materials into 3 groups, groupⅠ included S1 and S10, groupⅡ included S2, S3, S4, S8 and S9, group Ⅲ included S5, S6 and S7, and the differences among the groups were obvious. The principal component and cluster analysis could be used to analyze and comprehensively evaluate the agronomic traits of spring cabbage, to screen out excellent parental materials and provide a basis for breeding.

  Effects of Silicon and Calcium Fertilizer on Fruit Quality of Korla Fragrant Pear Zhang Feng, Li Yangyi, Zhang Xiaodong, Li Shiqiang 2020, 36 (4):  56-60.  DOI: 10.11924/j.issn.1000-6850.casb18100084 Abstract + ( 726 )   HTML ( 1 )   PDF ( 1040KB )   ( 198 ) The application effect of silicon fertilizer and calcium fertilizer on Korla fragrant pear was studied by field plot experiments. The results showed that compared with the control, five treatments all improved the fruit weight, fruit firmness, Vc content and soluble solids content of the Korla fragrant pear, and the content of titratable acid were all lower than that of control except for spraying calcium fertilizer and silicon fertilizer at the young and expanding stage, but the effect was small. Among the treatments, the effect of spraying calcium fertilizer combined soil application of silicon fertilizer was most remarkable in improving fruit weight, fruit firmness, Vc content and soluble solids content, which increased by 14.51%, 10.97%, 51.61% and 8.05% respectively compared with those of control, and the differences was all significant. Therefore, silicon and calcium fertilizer application has significant effect on both fruit quality and yield of Korla fragrant pear.

  Preliminary Study on Phenotypic Variation of Paeonia delavayi Under Homogeneous Environment Su Zechun, Li Zhaoguang, Xue Runguang, He Guiqing, Wang Zeqing, He Shoulian 2020, 36 (4):  61-66.  DOI: 10.11924/j.issn.1000-6850.casb19010060 Abstract + ( 421 )   HTML ( 0 )   PDF ( 1071KB )   ( 102 ) In this study, 13 phenotypic traits of 2-year-old Paeonia delavayi seedlings are used to systematically reveal the degree and regularity of phenotypic variation in different populations. The results showed that: the mean phenotypic differentiation coefficient of the 13 phenotypic traits was 99.57% under the condition of homogeneous environment, the phenotypic differentiation coefficient among populations was 82.76%, the phenotypic differentiation coefficient within populations was 0.32%. The variation among populations was greater than that within populations, indicating that the variation among populations was the main source of phenotypic variation. Previous studies have shown that the mean phenotypic differentiation coefficient of phenotypic traits in natural populations is 98.51%, of which, the phenotypic variation among populations is 48.87% and within populations is 0.59%. Compared with the variation of natural populations, under the condition of homogeneous environment, the phenotypic variation among populations is greater and the phenotypic variation within populations is smaller. The phenomenon indicates that phenotypic traits in populations tend to be more stable through cultivation and domestication, and the difference of phenotypic traits among populations is more obvious. The results can provide data support for establishing the peony core collection.

  The Effect of Matricaria chamomilla Essential Oil on Skin Wound Healing Shen Junlian, Zhang Nan, Li Yuhong, Yao Lei, Li Shuangyue 2020, 36 (4):  67-75.  DOI: 10.11924/j.issn.1000-6850.casb18110096 Abstract + ( 829 )   HTML ( 0 )   PDF ( 1914KB )   ( 138 ) This study aims to investigate the effects of Matricaria chamomilla essential oil on the proliferation and migration of fibroblasts and the wound healing in mice. The effects of different concentrations of M. chamomilla essential oil on the proliferation of fibroblasts were detected by CCK8 method, while the effects on the migration of fibroblasts were detected by scratch method. Excision wound model was established to evaluate the effects of M. chamomilla essential oil on the wound healing in mice. The results showed that: M. chamomilla essential oil significantly promoted the proliferation and migration of fibroblasts in a dose-dependent manner. Meanwhile, it significantly improved the wound healing rate of mice skin. The number of fibroblasts and the thickness of dermis of the wound skin in essential oil treatment group increased significantly compared with that in the control group. These results indicated that M. chamomilla essential oil could promote skin wound healing, and its mechanism might be related to promoting fibroblast proliferation and migration.

  Comprehensive Evaluation on Characters of Tea Varieties Suitable for Longjing Tea: Based on Multiple Statistic Huang Haitao, Ao Cun, Mao Yuxiao, Yu Jizhong, Zhang Wei 2020, 36 (4):  76-82.  DOI: 10.11924/j.issn.1000-6850.casb18090069 Abstract + ( 567 )   HTML ( 0 )   PDF ( 1236KB )   ( 595 ) The paper aims to determine the multi-trait evaluation index of tea varieties suitable for processing Longjing tea, and to establish a comprehensive evaluation system for agronomic traits of Longjing tea varieties, so as to provide technical support for identifying and screening suitable varieties or resources of Longjing tea. A total of 17 agronomic traits including leaf length-width ratio, 100-bud weight, leaf unfolding angle, L, a, b, C, amino acids, tea polyphenols, water extract, caffeine, phenol-ammonia ratio, appearance, soup color, aroma, taste and leaf bottom of 15 main tea cultivars (lines) in Zhejiang were compared. The suitability of Longjing tea varieties (lines) was evaluated by principal component analysis, cluster analysis and hierarchical analysis. The average coefficient of variation of 17 agronomic traits was 12.05%, the coefficient of variation of 100-bud weight was the largest (28.15%), and the coefficient of variation of leaf bottom was the smallest (0.86%). The variables of agronomic traits of Longjing tea were relatively independent and closely related. By analyzing 17 agronomic trait coefficients of 6 principal component function formulas, 17 agronomic traits could be divided into 3 main indexes: shape factor, endoplasmic factor and sensory factor. These 3 main indexes could accurately evaluate the suitable varieties of Longjing tea, among which the ratio of bud length to leaf width, a value, tea polyphenols, phenol to ammonia ratio, shape, aroma and soup color were main characters. By cluster analysis, 15 varieties could be divided into 2 large groups, and the suitability of Longjing tea could be sorted by AHP. It is feasible to comprehensively evaluate 17 agronomic traits of Longjing tea by using principal component analysis and cluster analysis in multivariate statistical analysis. Combining with AHP, more accurate ranking can be obtained, and comprehensive and objective evaluation can be made from different angles, which could provide references for tea plant breeding suitable for Longjing tea.

  Landscape and Ecological Benefit Analysis of Tree Species in Limestone Mountains Based on TOPSIS Method Zhang Ruming, Li Yiran, Li Zedong, Cao Zhen, Zhang Yongtao 2020, 36 (4):  83-89.  DOI: 10.11924/j.issn.1000-6850.casb18110009 Abstract + ( 676 )   HTML ( 1 )   PDF ( 1271KB )   ( 68 ) To select tree species for landscape greening and achieve ecological benefits of barren hills in limestone mountains, we took nine species of 10-year-old tree in the typical limestone mountainous area of central southern Shandong Province as research objects, and studied the landscape and ecological benefits by field sampling and quantitative analysis. The landscape benefits were evaluated from the seasonal variation, ornamental value, tree shape, plant species, green view index, canopy closure, penetration distance, crown width and plant height of the tree species, and the ecological benefits were evaluated from litter stock volume, soil bulk density, total soil porosity, increased water storage, permeation rate, amount of erosion, organic matter, carbon sink. Then excellent tree species suitable for planting in limestone mountains were selected. The results showed that among the nine tree species, the landscape and ecological benefits of Acer mono were the best, followed by that of Robinia pseudoacacia and Pistacia chinensis. This research could improve the quality of forests in limestone mountains and better use the multi-functional benefits of the forest in Shandong Province.

  Citrus Freezing Damage in Shiyan in 2018: Meteorological Condition Analysis and Preventive Recovery Measures Liu Tao, Wang Hualing, Wu Wei, Yu Li, Peng Jiaqing 2020, 36 (4):  90-94.  DOI: 10.11924/j.issn.1000-6850.casb18100056 Abstract + ( 614 )   HTML ( 8 )   PDF ( 1283KB )   ( 95 ) To rationally and scientifically utilize climate resources, aiming to response to periodic freezing injury, and sustainably develop the citrus industry in Shiyan, we conducted a detailed investigation on the freezing injury in main citrus production villages and towns in Shiyan, on the basis, studied the meteorological characteristics of the freezing injury by using the observational data from the agricultural meteorological station, and according to the grading standards of citrus freezing injury in field and the freezing injury indexes, quantitatively evaluated the performance of 11 main citrus varieties. The results showed that: the meteorological conditions of the freezing injury were low limit minimum temperature, long low temperature duration, large temperature change range, low temperature and high humidity, etc. After discussing the anti-freezing ability of the main citrus varieties, we put forward technical measures for preventing periodic freezing injury and post-disaster recovery from the aspects of citrus varieties, garden planning and field management according to the meteorological factors.

  Drought-Flood Evolution in Southwest Shandong from 1971 to 2015: Spatial and Temporal Distribution Characteristics Li Ruiying, Ren Chongyong 2020, 36 (4):  95-100.  DOI: 10.11924/j.issn.1000-6850.casb18090118 Abstract + ( 378 )   HTML ( 0 )   PDF ( 1204KB )   ( 108 ) The paper aims to analyze the spatial and temporal distribution characteristics of drought-flood in southwest Shandong. Based on the monthly precipitation data of 9 counties in the region from 1971 to 2015, we analyzed the variation characteristics of drought-flood by using the standardized precipitation index with different time scales. The results showed that: the flood was more frequent in the 1970s, drought increased in the 1980s, while it turned into flood in the 1990s, and drought continued to weaken, flood increased in the 2000s; the characteristics of seasonal changes all showed drought and flood occurred alternately while the flood occurred more frequently in summer, the linear trend of SPI in spring, summer, autumn were relatively stable, it had no obvious change trend, the flood in winter showed a slightly increasing trend while drought decreased with no obvious change trend; the trend of drought-flood in 3 areas were basically identical, showing an overall watering trend which did not reach the significant level; the rate of drought-flood was relatively stable from 1970s to the early 1990s while was the maximum in the early 21 st century, and there was obvious dry-wet change from the late 1990s to the early 21 st century. In southwest Shandong, the change of drought-flood has obvious stages and the occurrence is extremely frequent, and the whole process is flood-drought-flood.

  The Relationship Between Different Grades of Precipitation and Drought and Flood in Haidong, Qinghai Qi Donglin, Pei Yufang, Chao Hongyan, Zhao Huifang, Su Wenjiang 2020, 36 (4):  101-112.  DOI: 10.11924/j.issn.1000-6850.casb18100005 Abstract + ( 463 )   HTML ( 1 )   PDF ( 1603KB )   ( 96 ) Haidong is an important grain production base in Qinghai, and drought directly affects the orderly development of agriculture. Based on the daily precipitation data of 5 meteorological stations in Haidong from 1961 to 2015, we analyzed the variation trend of rain days and precipitation of different grades and Z index, and studied the effects of rain days and precipitation of different grades on drought and flood. The results showed that: (1) half-year precipitation in summer (winter) was dominated by light rain (snow) and moderate rain (snow), the precipitation and rain days of light rain and heavy rain (moderate rain) in summer half year were decreasing (increasing) and the precipitation and rain days at all grades in winter half year were decreasing; (2) the Z index in summer, winter half year showed an insignificant trend of decrease; (3) according to the analysis of partial correlation coefficient and relative contribution rate, the precipitation and rain days of medium rain and heavy rain in summer half year had significant influence on Z index, while the precipitation and rain days of light snow in winter half year had the greatest influence on Z index change; (4) the synthetic analysis showed that the precipitation and rain days of different grades were basically positive in flood years, the differences of precipitation and rain days of different grades was mainly shown in the heavy rain and moderate rain in summer half year, and the differences in winter half year was mainly reflected in the precipitation and rain days of light snow; in the dry year, the precipitation and rain days at all grades were basically negative, the differences in summer half year was mainly reflected in precipitation and rain days of moderate rain, while the differences in winter half years was mainly reflected in the precipitation and rain days of light snow and moderate snow.

  Main Rice Diseases and Insects Occurrence in Southwest Guangdong: Summary on Meteorological Laws and Predictions Chen Bing, Luo Youwen, Chen Guanhao, Peng Rongnan, Ma Lujin, Li Guolong, Liang Shengming 2020, 36 (4):  113-117.  DOI: 10.11924/j.issn.1000-6850.casb20190800569 Abstract + ( 608 )   HTML ( 0 )   PDF ( 1157KB )   ( 114 ) The survival, development and reproduction of rice insect pests, and the outbreaks and epidemic of rice diseases and pests are closely related to meteorological conditions. This study systematically summarized the research results of the relationship between the occurrence of major rice diseases and insect pests and meteorological conditions in Huazhou of Guangdong from 2000 to 2018, reviewed the prediction models established in Huazhou, analyzed the innovation and breakthroughs in this field, and compared the technology in Huazhou with that in other areas of China, in order to provide references for the future research and control of rice diseases and insect pests.

  Identification and Evaluation of 89 Fresh Corns Resistance to Sporisorium reilianum from Gansu Regional Trial Che Zhuo, Wang Chunming, Zhou Tianwang, Guo Cheng 2020, 36 (4):  118-122.  DOI: 10.11924/j.issn.1000-6850.casb18100115 Abstract + ( 661 )   HTML ( 0 )   PDF ( 1232KB )   ( 77 ) The paper aims to confirm the head smut resistance difference among fresh corn cultivars. We identified the resistance of 89 corn cultivars in Gangu, Tianshui of Gansu by the method of artificial inoculation in field during 2015-2017. The results showed that: among the 89 fresh corn cultivars, 9 were highly resistant, including ‘cainuo1’,’gantiannuo1’, ‘qinliangnuo902’, ‘jiuyangshuangsemi’, ‘AP358’, ‘jiunuo4103’, ‘yayu1’, ‘henuo1’ and ‘tianfunuo1’; 5 cultivars were resistant, including ‘baonuo1’, ‘tianfunuo2’, ‘gankennuo2’, ‘jinhui306’ and ‘ruinuo260’; 9 cultivars were moderately resistant, including ‘huatianyu6’, ‘baiyu909’, ‘zhuonuo606’, ‘12009’, ‘yinyu16’, ‘huangnuo90’, ‘baitiannuo828’, ‘yuanyunuo505’ and ‘zhongtian5’; the other 36 and 30 cultivars were susceptible and highly susceptible; HR, R, MR, S, HS accounted for 10.11%, 5.62%, 10.11%, 40.45% and 33.71%, of the 89 cultivars respectively.

  Effect of Traditional Chinese Medicine Antiviral Compounds on Virus Controlling, Yield and Quality of Radix Pseudostellariae Zheng Mingqiang, Wang Ruoyan, Wang Daoping, Pan Weidong, Liu Xiaolan, Yang Ying, Li Chunyan, Li Zhong, Xiao Minlian, Zhang Zhong 2020, 36 (4):  123-129.  DOI: 10.11924/j.issn.1000-6850.casb20190900633 Abstract + ( 581 )   HTML ( 0 )   PDF ( 1637KB )   ( 123 ) Different antiviral formulations for virus diseases of radix pseudostellariae were formed, in which No.1 and No.3 compounds were based on traditional Chinese medicine prescription theory, and the others were based on the superposition of medicinal plant chemical components. The plots of radix pseudostellariae cultivated for 2 years in succession were selected for complete block experiment. The aim of this experiment is to investigate the effects of different treatments on virus control effect, yield and quality of radix pseudostellariae in field. The results indicated that the virus disease incidence of No.1 compounds treatment was 63.37% lower than that of the control group (P<0.01), and the disease index was 90.61% lower than control group, with the highest control effect (90.63%, P<0.01), while the virus control effect of the other 4 treatments were all higher than 80%. When the virus disease index was above grade 5, No.1 compounds treatment could prevent the spread of the virus after one application. After three applications, the leaves of infected radix pseudostellariae could be recovered. After five applications, leaf spots and symptoms of infection completely disappeared with bright color, and the plants returned to normal growth. No.1 and No.3 compounds treatment increased the yield significantly, by 197% and 159% compared with that of the control (P<0.01). The yield of other treatments was 68%, 69% and 68% (P<0.01) higher than that of the control, respectively. No.1 and No.3 compounds treatment could also increase the contents of total polysaccharide and cyclic peptide B of radix pseudostellariae. The total polysaccharide content of No.1 compounds treatment was the highest (14%), and the content of cyclic peptide B of No.3 compounds treatment was the highest (11%). In a word, No.1 compounds treatment has significant effects on preventing and controlling viral diseases thus improving yield and quality, which can be selected for the next round of test. Formulation based on traditional Chinese medicine prescription theory works better than formulation based on superposition of medicinal plant chemical components, especially on improving the quality of medicinal materials. The study could provide an organic multi-effect measure to control the virus disease and recover the infected plants of radix pseudostellariae.

  Extracts of Brassica juncea: Antibacterial Activity to Watermelon Fusarium Wilt and Antibacterial Spectrum Determination Liu Lin, Ruan Renwen, Zhang Rui, Wang Qiang, Ma Xiling, Li Shanshan, Fan Shuying 2020, 36 (4):  130-134.  DOI: 10.11924/j.issn.1000-6850.casb18110043 Abstract + ( 422 )   HTML ( 2 )   PDF ( 1310KB )   ( 123 ) To study the antibacterial activity of extracts of Brassica juncea, lay a foundation for the development of B. juncea as a fungicide for agricultural production, and provide a basis for the rational use of B. juncea resources, we tested the antibacterial activities of extracts of B. juncea against Fusarium oxysporum f. sp. niveum, Rhizoctonia solani, Botryosphaeria parv and Phytophthora parasitica var. nicotianae by means of mycelium growth rate method. The results showed that: different organic solvent extracts from B. juncea had certain inhibitory effect on watermelon fusarium wilt; the antibacterial effect of extracting with 95% ethanol was the best, and the antibacterial rate of the extract could reach more than 90%; its minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MFC) were 0.5 g/mL and 1.0 g/mL, respectively; through the determination of virulence equation, its half bacteriostatic concentration was 0.2212 g/mL. The antibacterial activity of the other 10 plant phytopathogens showed that: the ethanol extracts of B. juncea had strong antibacterial activity against 4 phytopathogens, such as Rhizoctonia solani, Botryosphaeria parv, Phytophthora parasitica var. nicotianae, and Sclerotinia sclerotiorum with the EC50 0.0898 g/mL, 0.1265 g/mL, 0.1679 g/mL and 0.1685 g/mL, respectively, and the inhibition effect against the Colletorichum gloeosporioides was the weakest, and the EC50 was 0.5833 g/mL. The extracts of B. juncea have strong antifungal activities with broad control spectrum, and it is worth further researching.

  Polyphenol Extraction from Forsythia suspensa Fruit and Application of Compound Coating Preservative in Grape Freshness Preservation Zhang Xiaohu, Li Qian, Wei Xiaxia, Liu Gengmei, He Yong 2020, 36 (4):  135-141.  DOI: 10.11924/j.issn.1000-6850.casb18100113 Abstract + ( 793 )   HTML ( 3 )   PDF ( 1338KB )   ( 89 ) The paper aims to select preservative and fresh-keeping ingredients from plant sources for food preservation. The polyphenols of Forsythia suspensa fruits were extracted by ethanol extraction combined with constant temperature magnetic stirring water bath. The optimal extraction process was determined by orthogonal design of L9(3 4). Grapes were covered by the combination made of F. suspensa polyphenol, phytic acid, calcium chloride and citric acid with chitosan. Subsequently, the fresh-keeping effect was studied. The results showed that the optimized extraction condition was: material liquid ratio of 1:10 (g:mL), the ethanol concentration of 60%, the extraction temperature of 60℃ and the extracting time of 2.5 h. Under the optimized condition, the F. suspensa fruit polyphenol extraction yield could reach 7.21%. Preservatives made of 2% F. suspensa polyphenols, 1% calcium chloride, 0.15% phytic acid, 2% citric acid and 1% chitosan could play an active role in keeping grapes fresh during storage.

  Browning During Storage of Dried Hami Melon: Analysis and Evaluation Yu Jiajia, Cao Ya, Xu Jian 2020, 36 (4):  142-146.  DOI: 10.11924/j.issn.1000-6850.casb18110038 Abstract + ( 450 )   HTML ( 0 )   PDF ( 1259KB )   ( 154 ) In this paper, the influence of the drying and packaging method on the browning of cantaloupe was studied, and the relationship between the non-enzymatic browning factors and the browning degree was analyzed. The results showed that compared with the NaHSO3 processing, browning risk of shade-drying Hami melon existed in the process of storage, packing method had no significant effect. In the process of storage, the factors of non-enzymatic browning factors were changed, but the correlation between browning factors and browning effect was greatly influenced by the drying method. Under different treatment conditions, soluble protein content was not significantly correlated with browning degree. There were significant or extremely significant correlations between the browning degree and free amino acids, reducing sugars, Vc, total phenol, carotenoids and other indexes under the shade-drying. There was no significant correlation between the browning degree and non-enzymatic browning factors under NaHSO3 vacuum packing, and the browning was significantly inhibited.

  Effects of Different Extraction Fibers on Volatile Compounds of Pyrus bretschneideri Flowers Ma Weihua, Li Lixin, Shen Jinshan, Wu Wenqing, Song Huailei, Zhang Xufeng, Li Jie 2020, 36 (4):  147-150.  DOI: 10.11924/j.issn.1000-6850.casb20190800561 Abstract + ( 623 )   HTML ( 1 )   PDF ( 1256KB )   ( 135 ) To understand the physiological and ecological function of pear flower scents, the volatile compounds of Pyrus bretschneideri flowers were analyzed by headspace solid phase microextraction (HS-SPME) and GC-MS. The extraction effects and characteristics of 65 μm PDMS/DVB and 50/30 μm DVB/CAR/PDMS were compared. Results showed that the number and type of volatile compounds of pear flowers detected by 65 μm PDMS/DVB and 50/30 μm DVB/CAR/PDMS extraction heads were respectively 20 and 41 species, 5 and 10 types of substances, of which, alkane had the most kinds and the highest content (7 types, 38.63%) among the volatile organic compounds detected by 65 μm PDMS/DVB extraction heads, while alkenes (7 types, 41.16%) and alcohols (7 types, 24.11%) were the main compounds detected by 50/30 μm DVB/CAR/PDMS extraction heads. According to the number, type and content of extracted compounds, the 50/30 μm DVB/CAR/PDMS extraction heads are more suitable for extracting and analyzing the volatile compounds of pear flowers.

  The Nitrite Content of Huizhou Meicai Zhu Wenjuan, Weng Jia, Chen Wencai, Liang Jiahong, Ye Wenfang, Huang Xiuli 2020, 36 (4):  151-155.  DOI: 10.11924/j.issn.1000-6850.casb18100068 Abstract + ( 944 )   HTML ( 4 )   PDF ( 1291KB )   ( 129 ) For safe production and risk monitoring in the production process of Huizhou meicai (a kind of pickled vegetable), this paper used naphthalene ethylenediamine hydrochloride colorimetric method to study the content of nitrite in Huizhou meicai at different pickling periods. The results showed that the nitrite content was related to the salt dosage and pickling time. At the temperature of 10-15℃, 14% and 30% salt dosage had the highest nitrite value on the second day, which was 11.85 and 18.28 mg/kg, respectively, and decreased to 1.95 and 2.17 mg/kg on the sixth day; moreover, the nitrite content decreased to less than 1.00 mg/kg after 30 days of drying and stacking. The nitrite content of 234 batches of products was lower than the national limit of nitrite in pickled vegetables (< 20 mg/kg), and the proportion of nitrite content below 5 mg/kg was 94.8%.

  Design and Measurement of Farmers’ Social Network Relationship Evaluation System: Based on 1440 Survey Data Wang Lei, Xia Yuxin, Jiang Mingdong, Zhong Guanyu, Du Dong 2020, 36 (4):  156-164.  DOI: 10.11924/j.issn.1000-6850.casb18090017 Abstract + ( 516 )   HTML ( 1 )   PDF ( 1251KB )   ( 290 ) The evaluation index system of farmers’ social network relationship is constructed from five aspects: work scale, network tightness, trust and commitment, social atmosphere, sense of belonging and social participation. According to the regional distribution, the investigated area was divided into Hetao area, Central Plains region and Guanzhong region. The weight of each index was determined by coefficient of variation method, and then the level of social network relationship of farmers was measured. The results showed that: according to the weight, the order was social participation, network scale, network tightness, trust and commitment, social atmosphere and sense of belonging, farmers’ social network relationship evaluation value was low as a whole, showing a positive skewness distribution and regional differences; Guanzhong region was the highest, but the individual differences were obvious, followed by the Hetao area and the Central Plains region. According to the results of the first-level index, social participation scored the highest, followed by social atmosphere and sense of belonging, trust and commitment, and finally the network scale and network tightness. It can be seen that farmers are more willing to participate in collective action, and the human environment has been further improved; Geographical relationship and kinship limit the scale of the network, and the expansion and the loss of rural population also weaken the network tightness. On the basis of this study, the relevant suggestions are put forward to provide a basis for relevant government agencies to implement rural governance.