Current issue

• 2019 Vol.35 No.30 Published:25 October 2019

  Restoring Ability of WA Type Male Sterile Cytoplasm: Identification with introduced rice germplasm resources 2019, 35 (30):  1-7.  DOI: 10.11924/j.issn.1000-6850.casb20190500159 Abstract + ( 444 )   PDF ( 1234KB )   ( 140 ) In order to study the restoring or remaining characteristics and the distribution of restoring resources, 441 rice germplasm resources from Asia, Europe, Africa, North America and South America were detected through test crossing screening, which also would provide excellent parents for efficient breeding of restorer line or maintainer line. Using WA-CMS line ‘Ming 218A’as the female parent, 441 germplasm resources were selected as the tester. The restoring or remaining characteristics of the rice resources were identified by the natural seed setting rate, and the results showed that the number of resources with restoring ability, remaining ability and the middle type were 53, 43 and 333, respectively. According to the distribution of restoring varieties, there were 33 varieties from Asian countries (regions), accounting for 62.3% of restoring resources. 6 restorable varieties were from USA, accounting for 31.6% of USA germplasm resources ,which indicated that the USA germplasm resources contained more restorable varieties. Only 2 restorable varieties were identified from European, accounting for 5% of the European germplasm resources, which indicated that Europe had fewer restorable resources. Correlation analysis was carried out by the mean values of the seven important traits of F1 and the male parent, the plant height (r=0.97**), 1000-grains weight (r=0.934**) and panicle length (r=0.747**) had significant relationship with the male parent, while the other 4 traits were not significantly related with the male parent. The desending order of relevance was plant height, 1000-grains weight, panicle length, panicles of per plant, spikelets of per panicle, filled spikelets of per panicle, natural seed setting rate. In our study, resources with high restoring ability were distributed in all five continents, mainly in the East Asia, South Asia and Southeast Asia and USA. The plant height, 1000-grain weight and panicle length of the restorer line had more obvious effect on the hybrid F1.

  Scrapped Propellant Decomposition Products: Effects on Wheat After Anthesis Under High Temperature Stress 李燕,,,,谭德水,房锋 and 林海涛 2019, 35 (30):  8-15.  DOI: 10.11924/j.issn.1000-6850.casb18050115 Abstract + ( 637 )   PDF ( 1707KB )   ( 176 ) Scrapped propellant decomposition products (SPDP) is a new type of fertilizer in agricultural production, which comes from the product of reused scrapped propellant. In order to study the influence of SPDP on wheat under high temperature stress, the greenhouse pot test was carried out. Spectrophotometer method was used to determine the physiological indexes related to the growth metabolism and stress resistance of wheat. Result showed the different compoments of SPDP were all benefit to the growth and the high temperature resistance of wheat after anthesis. Among them, T8 test has the best effect. T1 test contained nitrogen, so it significantly increased the nitrate reductase activity, sucrose phosphate synthase activity, chlorophyll content and root activity, compared with the control. T2 test contained trace diphenylamine, which significantly improved antioxidant enzyme activity, and reduced the content of malondialdehyde. In conclusion, the SPDP was beneficial to wheat growth and improved the high temperature resistance of wheat, which could be used in agricultural production as a new kind of fertilizer with high quality and environmental protection.

  Characteristics of Grain Filling and High Yield and Early Maturity of Different Genotypes of Maize 2019, 35 (30):  16-21.  DOI: 10.11924/j.issn.1000-6850.casb18060028 Abstract + ( 512 )   PDF ( 1200KB )   ( 151 ) The aims are to illustrate the differences of yield, maturity and grain filling in different maize genotypes, and to provide a basis for the maturity selection of maize mechanized harvest. Three maize varieties ‘Xindan 68’,‘Xindan 61’and‘Zhengdan 958’were used as the experimental materials, the changes of growth period, quality, fresh weight of kernel, volume and dry weight of kernel were studied. The yield and yield components were compared and analyzed. The results showed that compared with‘Zhengdan 958’, the parent of‘Xindan 68’had earlier maturity, higher starch content and short growth period. The kernel volume of‘Xindan 68’and‘Xindan 61’had not obvious difference. The kernel dry weight of‘Zhengdan 958’ increased steadily after pollination. In 24 days after pollination, the kernel dry weight of‘Xindan 61’and ‘Xindan 68’increased rapidly, while after 24 days, they increased slowly. The yield of‘Xindan 68’was significantly higher than that of‘Zhengdan 958’, the moisture content of‘Xindan 68’and‘Xindan 61’were significantly lower than that of‘Zhengdan 958’. In conclusion,‘Xindan 68’has short growth period, high starch content, quick grain fill at later stages, and thinner ear axis, which indicate that the kernel of‘Xindan 68’ is easy for dehydration and suitable for mechanized harvest.

  Potassium and Sodium Levels and Sugar Beet Seedlings: Effects on Physiological Characteristics 2019, 35 (30):  22-30.  DOI: 10.11924/j.issn.1000-6850.casb19030122 Abstract + ( 467 )   PDF ( 1266KB )   ( 118 ) The aim is to provide theoretical basis for the rational application of potassium and sodium in sugar beet production. Using sugar beet variety ''ST13092'' as material, three K+ levels (0.03, 1.5 and 3 mmol/L) and three Na+ levels (0, 1.5 and 3 mmol/L) were set under hydroponic conditions. At the same time, K+ and Na+ interacted for a total of 9 treatments. After 3 weeks of culture, the effects of different potassium and sodium levels on water potential, relative water content, chlorophyll content, photosynthetic characteristics, Na+ and K+ content, N, P and organic acid content of sugar beet seedlings were determined. The dry weight, leaf area, water potential, relative water content, transpiration rate, stomatal conductance, net photosynthetic rate and intercellular CO2 concentration of sugar beet seedlings increased significantly with the increase of K+ supply level and Na+ supply level, while the contents of chlorophyll a, chlorophyll b, N, P and organic acids decreased. When both K+ and Na+ were 3 mmol/L, the water potential, relative water content, transpiration rate, stomatal conductance, net photosynthetic rate, intercellular CO2 concentration, Na+ and K+ contents reached the maximum, and chlorophyll a and chlorophyll b contents, N, P contents reached the minimum.Potassium, sodium and their interactions not only directly increase the water potential and leaf area of leaves, promote photosynthesis, but also increase the osmotic regulation of potassium and sodium ions, reduce the role of organic osmotic regulation, and indirectly improve the utilization rate of photosynthetic products, promote the growth of seedlings, and regulate the content of N and P in plants.

  Direct Regeneration System of Sugar Beet: Establishment and Optimization 2019, 35 (30):  31-36.  DOI: 10.11924/j.issn.1000-6850.casb20190500209 Abstract + ( 550 )   PDF ( 1436KB )   ( 261 ) The study aims to establish a direct regeneration system for cultivated sugar beet in northeast China, and lay a foundation for the cultivation of sugar beet varieties by genetic engineering. In this study, cotyledonary sections and petioles were used as explants to study the effects of different disinfection methods and hormone levels on the induction of adventitious bud and adventitious root. The results showed that: the best disinfection method was stripping the seed shell to obtain seeds and the lowest pollution rate was performed using 75% alcohol for 30 s and 0.1% HgCl2 for 5 min; the optimum ratio of hormone to the induction of adventitious bud was MS+6-BA 0.5 mg/L+NAA 0.05 mg/L; the induction rate of adventitious bud using both cotyledon and petiole were biggest with 14.44% and 11.67%, respectively; the optimum ratio of hormone to induce adventitious root was 1/2MS + NAA 0.05 mg/L, and the induction rate was 93.33% . This study preliminarily establishes the direct regeneration system for sugar beet in northeast China, laying the foundation for the establishment of genetic transformation system and genetic improvement of sugar beet.

  Effect of Chelate Fertilizers on Growth and Quality of Crops 2019, 35 (30):  37-41.  DOI: 10.11924/j.issn.1000-6850.casb18050140 Abstract + ( 341 )   PDF ( 1145KB )   ( 289 ) Long-term application of inorganic fertilizer could lead to environmental problems, chelate fertilizer performs well in agricultural due to their special structural specificity, it plays a positive role in promoting crop growth and quality, and has been applied to high economic growth crops. On the basis of existing researches, we reviewed the effects of chelated fertilizers on crops, including growth indexes such as appearance, chlorophyll and yield, and quality indexes such as vitamin C, carbohydrates, protein, trace element content, soluble solids, storage quality, nitrate nitrogen, etc. Finally, we analyzed the main characteristics of four chelate agents, to provide a basis for the promotion and application of high quality chelate fertilizer in agriculture.

  Research Progress on Isolating Microspores Culture of Tomato 2019, 35 (30):  42-48.  DOI: 10.11924/j.issn.1000-6850.casb19020012 Abstract + ( 506 )   PDF ( 1221KB )   ( 166 ) Androgenesis is a process, which microspores or immature pollen cells regenerate plants by the sporophytic development pathway, and that is one of the effective ways to create breeding materials. To establish the stable microspore culture method, with higher regeneration rates, this paper reviewed the domestic and foreign research results, summarized the main influence factors of androgenesis stages (obtainment of embryogenesis, induction of embryos and regeneration of haploid plants), and concluded the culture techniques of isolating microspores. The analysis showed that genotype was restrictive?factors, and androgenesis could deviate from the gametophyte pathway, when the influence factors appear at the same time. In the end, we discussed the future research direction of microspore culture, and expected to offer reference for the deepening research of doubled haploid technology in tomato.

  Hydrolysate of Burdock Root: Preparation and Its Effect on Melon Growth and Quality 2019, 35 (30):  49-57.  DOI: 10.11924/j.issn.1000-6850.casb18060076 Abstract + ( 317 )   PDF ( 1313KB )   ( 271 ) The paper aims to increase the yield of the enzymatic hydrolysate of burdock root waste and to test its fertilizer efficiency. We optimized the complex enzyme composition and the enzymatic hydrolysis conditions by adopting the response surface method, and tested the effects of the enzymatic hydrolysate on the growth and quality of melon through the pot experiments. The results showed that: the optimum composition of the complex enzyme was cellulase 47.3%, neutral protease 1.0%, and alkaline protease 51.7%, the optimum hydrolysis conditions were 49.9℃, pH 6.42, substrate concentration 6.94%, and the ratio of enzyme to substrate 2.536%; when burdock root waste was hydrolyzed under the optimized conditions for 3 h, the yield of the enzymatic hydrolysate was 74.83%, the yield of soluble protein was 11.06%, and the yield of soluble sugar was 37.49%. The enzymatic hydrolysate was rich in organic matter, soluble sugar and amino acids, which could promote the growth of melon and improve its yield and quality. It is technically feasible to hydrolyze burdock root waste with complex enzyme; the enzymatic hydrolysate is of high yield and rich in organic nutrients which can be used as water-soluble organic fertilizer.

  Climate Quality Certification Technology of Yuanjiang Red Heart Pitaya 2019, 35 (30):  58-63.  DOI: 10.11924/j.issn.1000-6850.casb20190500218 Abstract + ( 485 )   PDF ( 1267KB )   ( 120 ) S[Objective] In order to reflect the local climate characteristics and resource advantages, improve the competitiveness of "famous and excellent" agricultural products, and serve for Yuanjiang County pitaya industry. [Method] By collected the data of growth period, food composition and meteorological observation data of Pitaya fruit, the multiple linear regression equation between the components of soluble solids, anthocyanins, vitamin C and meteorological data of pitaya fruit and meteorological data was determined through expert consultation and mathematical statistics analysis, and the weight was determined to obtain the formula of the climate quality certification index of Pitaya fruit. [Result] Based on the idea of normalization, the formula of climate quality certification indicators obtained by determining the weight can be flexibly adjusted according to the increase of actual samples. At the same time, the artificial evaluation factors such as garden management level and disaster grade were not introduced. The regression equation of the content of edible ingredients mainly includes meteorological factors such as temperature, humidity and irradiance, which was consistent with the previous research results. [Conclusion] According to the formula of certification index, the certification score of a batch of pitaya fruit in the orchard in 2018 was above 90 points, which reached the "excellent" grade. The certificate of climate quality of agricultural products was issued to the applicant, and the two-dimensional code of certification traceability was provided for the company to bi listed on the market.

  Optimization of Medium Components and Cultivation Condition for Pollen Germination in Vitro in Heuchera Plants 2019, 35 (30):  64-70.  DOI: 10.11924/j.issn.1000-6850.casb18060050 Abstract + ( 469 )   PDF ( 2048KB )   ( 152 ) To screen out an appropriate medium component in vitro and a suitable cultivation condition for Heuchera plants, Heuchera ‘Hongzhuangmeiying’ was used as materials. In this study, three factors including pH value of medium, cultivation temperature, and cultivation time were firstly optimized by single factor experiments, and then an orthogonal experiment was further designed to optimize the formula of pollen germination in vitro for Heuchera ‘Hongzhuangmeiying''. The results demonstrate that the pollen germination rate is the highest when the pH value of medium is 5.5, cultivation temperature is 25℃, and the cultivation time is 120 min, and the effects of 4 factors on the pollen germination in vitro for Heuchera ‘Hongzhuangmeiying’ are as following: sucrose> PEG4000 > boric acid >calcium chloride. The best combination is the eleventh treatment (A3B1C3D5) formulated with 10 % sucrose, 0 mg/L calcium chloride, 100 mg/L boric acid, and 20 % PEG4000, and the highest average pollen germination rate attained to 73.2 %. This optimization results would give a good foundation for the studies associated with pollen vitality for Heuchera plants.

  Osmotic Stress: Effects on in vitro Mutagenesis System of EMS in Hemerocallis hybrida 2019, 35 (30):  71-77.  DOI: 10.11924/j.issn.1000-6850.casb18070107 Abstract + ( 405 )   PDF ( 1609KB )   ( 82 ) The study is to improve the rate of EMS mutants of Hemerocallis hybrida. The pre selected highly permeable solid medium(mannitol 36g/L+ sorbitol 36g/L+ sucrose 50g/L) was used in the experiment. The callus of Hemerocallis hybrida was treated with osmotic stress at different time span and then induced by 0.1%EMS semi lethal dose. The effect of osmotic stress on the mutagenic effect of EMS was studied. The growth state, survival rate, differentiation rate and seedling growth rate of callus after osmotic stress and EMS mutation were observed and statistically analyzed. And cell membrane permeability and SOD, POD, CAT enzymes were determined. Results：Osmotic stress pretreatment has some effects on EMS mutagenic effect. Osmotic stress enhanced the damage of EMS to callus. The cell membrane permeability and the activity of SOD and CAT enzymes increased, and the activity of POD decreased. Osmotic stress 30min-60min had no significant effect on the ability of callus differentiation,but increase the mutant rate 6.34%-9.27%. Osmotic stress induced lethal damage to callus in 90min. Conclusion ：Before the 0.1%EMS semi lethal dose induced the callus of Hemerocallis hybridai, a high permeable solid medium (mannitol 36g/L+ sorbitol 36g/L+ sucrose 50g/L) was used for 30min-60min stress pretreatment to improve the mutant rate of 6.34%-9.27%.There is no regularity in the duration of osmotic stress and the rate of increase in mutation rate.

  The Progress of Plant Acyl-CoA-binding Proteins 2019, 35 (30):  78-83.  DOI: 10.11924/j.issn.1000-6850.casb18050150 Abstract + ( 400 )   PDF ( 1351KB )   ( 102 ) Acyl-coenzyme A (CoA)-binding proteins (ACBPs) are a class of lipid transporters. They have high binding abilities to acyl-CoAs and phospholipids, and in plant development and stress responses, they play important roles. According to the differences of the domain architecture and protein molecular weight, plant ACBPs are divided into four classes. With the increase of the known genome sequences of plant species, in more and more plants, ACBPs are found. ACBPs from different plant species show diversified subcellular localizations and biological functions. To find out the functional changes of plant ACBPs gene family occurred in terrestrial plant evolution, especially after the split of monocots and dicots, it was summarized that the reported subcellular localizations and gene functions of plant ACBPs. And focusing on Class IV ACBPs from 84 different plant species, the amino acid sequences were multiply aligned and phylogenetic relationship analyses were conducted. The monocots and dicots Class IV ACBPs, besides having conserved functional domain sequences, possessed their own unique sequence characteristics. The above sequence distinctions will provide valuable information for the investigation on the subcellular localizations and gene functions of Class IV ACBPs in plants. Finally, it was proposed that the functions of ACBP are diverged with the split of monocots and dicots.

  Docosahexaenoicacid Produced by Crypthecodinium cohnii: Research Progress 2019, 35 (30):  84-90.  DOI: 10.11924/j.issn.1000-6850.casb18050042 Abstract + ( 385 )   PDF ( 1332KB )   ( 112 ) Docosahexaenoicacid (DHA) is a class of polyunsaturated fatty acid with important physiological functions which the body could not synthesis. Exogenous supplementation of DHA can enhance immune function, physical fitness of human beings. Crypthecodinium cohnii is one of the ideal raw materials for the production ofDHA. In order to carry out DHA research on the large-scale production of Crypthecodinium cohnii in the future, this paper comprehensively analyzed the problems of the species of Cryptococcus, DHA biosynthesis, and the influence of culture conditions on DHA accumulation.Specifically, (1) the DHA production of the siblings of the cryptophyta is different, and the mutants can be screened to obtain new excellent lines by mutagenesis; (2) the biosynthesis of DHA is different from the biosynthesis of other fatty acids, The synthetic route is speculated, possibly the PKS pathway; (3) environmental conditions, including temperature, light, pH, dissolved oxygen, inoculum, defoaming, etc., and medium composition, including carbon source, nitrogen source, Culture conditions such as inorganic salts and trace elements affect the content of DHA in algae. Mutagenesis is a feasible method for obtaining high-yield DHA strains, and put forward the research prospect of DHA production by Cryptophyta.

  Effect of Funneliformis mosseae on the Continuous Cropping Soybean Root and Soil Rhizosphere Enzymes Activities 2019, 35 (30):  91-98.  DOI: 10.11924/j.issn.1000-6850.casb18050153 Abstract + ( 1055 )   PDF ( 1443KB )   ( 235 ) The authors used‘Heinong 48’ (high- protein type) soybean as material, inoculated the Fueneliformis mosseae into soils surrounding the root system, and conducted continuous cropping by spatial method instead of time method. Then the F. mosseae infection on soybean roots was detected by supplying the acid magenta to calculate the incidence of root rot according to the following classification standard. Also, chemical titration and colorimetry were used to detect the changes of enzyme activity in treated soybean root system as well as rhizosphere soil. In the process of experiment, we selected soil of different continuous cropping years (1, 2 and 4 years) for pot trials, and set the non-inoculation of F. mosseaeas a control group (C) while made the inoculation of F. mosseae as a treatment group (T). The results showed that, as continuous cropping years increased, the enzyme activities of catalase (CAT), polyphenol oxidase (PPO), peroxidase (POD) and phenylalanine ammonia-lyase (PAL) in soybean roots increased, but the SOD enzyme activity showed a downward trend. In addition, with the growth of soybean, soil enzyme activity decreased gradually, in which soil urease (URE), CAT, sucrose (SUC), phosphatase (PHO) and PPO activity decreased first and then increased, and the activity of cellulase (CEL) gradually decreased. In conclusion, the defense enzyme activity and soil enzyme activity of soybean roots after F. mosseae inoculation were significantly higher than that of the control group, which indicated that F. mosseae could alleviate continuous cropping obstacle and improve disease resistance of plant.

  Cultivated Land Resources in Heilongjiang: Security Research 2019, 35 (30):  99-105.  DOI: 10.11924/j.issn.1000-6850.casb20190500092 Abstract + ( 343 )   PDF ( 1265KB )   ( 78 ) To improve the research on the security of cultivated land resources in various regions, taking Heilongjiang, a province with concentrated contiguous arable land, as a research area, we constructed a security evaluation index system for cultivated land resources, and quantitatively analyzed the security status and trend of cultivated land in Heilongjiang from 2007 to 2016 by the entropy method, comprehensive evaluation method and obstacle degree model. The results showed that: (1) the security of cultivated land resources in Heilongjiang experienced the“critical safety-safer-critical safety-safer”fluctuations from 2007 to 2016; (2) through the analysis of the criteria layer scores and trends, we found that the ecological security score had a big fluctuation, and the ecological security problem of cultivated land was prominent; (3) after calculating the index data of the research area from 2007 to 2016 with the obstacle degree model, we found that the obstacle degree of the ecological security index factor was more and more prominent in the middle and late period; the problem was concentrated on the excessive input of agricultural chemical production materials. Based on this, it is necessary to control the input of chemical production materials and implement effective crop rotation, fallow system and agricultural production compensation mechanism.

  Ecological Changes of Minqin Oasis Since Comprehensive Management of the Shiyang River Basin 2019, 35 (30):  106-111.  DOI: 10.11924/j.issn.1000-6850.casb18050071 Abstract + ( 504 )   PDF ( 1207KB )   ( 114 ) Based on the related data of the Minqin Meteorological Administration, the Water Affairs Bureau, the Forestry Administration and field investigation, the ecology of Minqin oasis were analyzed since the comprehensive treatment of the Shiyang River Basin. The results show that: (1) the dust weather and atmospheric dust-fall decreased obviously; (2) the moving velocity of sand dunes tend to be gentle, advance and retreat speed of the desert decreases, most of the sand dunes and deserts on the edge of the oasis have been effectively controlled; (3) the surface water quantity is increasing annually, the amount of groundwater exploitation and the decline rate of groundwater level decreases obviously, the groundwater level of the key governance area has a certain recovery; (4) the artificial afforestation and the sand pressing area are increasing annually, the vegetation coverage and the forest coverage rate are improved obviously. The ecological deterioration trend of Minqin oasis has been curbed after the comprehensive treatment, and partial region are improved and restored. The comprehensive treatment of Shiyang River Basin achieved remarkable results.

  Single and Complex Green Chelates: Effect on the Enrichment of Cadmium and Arsenic in Amaranthus mangostanus L. 2019, 35 (30):  112-118.  DOI: 10.11924/j.issn.1000-6850.casb20190500139 Abstract + ( 484 )   PDF ( 1280KB )   ( 105 ) [Objective]To provide a basis for the actual field phytoremediation of soil contaminated by Cd and As, the effects of complex green chelates in process of phytoremediation was explored. [Method]Single green chelates was applied to the soil polluted by cadmium (Cd) and arsenic(As) in vegetable fields: OA(Oxalic acid), TA(Tartaric acid), MA(Malic acid), IDS(Iminodisuccinic acid sodium salt) and PASP(Polyaspartic acid), and we did a pairwise compounding to explore the effects of different treatments on the growth and heavy metals enrichment of amaranth in the field. [Result]The results showed that: the biomass of amaranth which had been treated by PASP-MA and PASP-TA, in which PASP-MA ranked first, and its biomass values were 4.53 kg/m2. There was a significant difference in the concentration of heavy metals in different organs of kenaf(P<0.05). The accumulation of heavy metals in the below-ground was higher than that in the above-ground, but the bioconcentration factors were < 1; thus, they did not reach the values as high hyperaccumulating plants. According to the bioaccumulation coefficients(BCF)of amaranth on Cd and As, only the 处理 of IDS-MA enhanced the phytoremediation of Cd and As. The transfer factor (TF) of amaranth to Cd was increased in 7 Complex 处理s in which the TF reach to 0.90, which was 51.3% higher than controls. In complex green chelates, the TF of amaranth which had been treated by IDS-MA and IDS-PASP was 1.88 and 0.11 times higher than controls. S[Conclusion]In general, amaranth has a large biomass and short growth cycle. The enrichment of Cd and As in amaranth could be improved by adding IDS-MA, and laid a theoreticalSfoundation for phytoremediation of Cd、As contaminated soil in Guangdong.

  Enrichment Characteristics of Cadmium by Six Plants in Soil 2019, 35 (30):  119-123.  DOI: 10.11924/j.issn.1000-6850.casb18050032 Abstract + ( 828 )   PDF ( 1209KB )   ( 183 ) To screen cadmium removal plants that can adapt to moderate and light heavy metal pollution in farmland, field experiments were conducted to study the effects of six plant species (sweet sorghum, biomass sorghum, corn, oil sunflower, Phytolacca acinosa and Amaranthus hypochondriacus L.) on Cd in typical heavy metal cadmium polluted areas in Hunan. The results showed that the content of cadmium in plants was greatly influenced by the plant varieties and the content of cadmium in soil. The contents of cadmium in the upper part of the 6 plants at the 3 test points were: Amaranthus hypochondriacus L. > Phytolacca acinosa> biomass sorghum> oil sunflower> sweet sorghum> corn, and Zhuzhou> Xiangtan> Liling. In addition to corn, the enrichment coefficient of cadmium in the upper part of other plants was more than 1, which had the characteristics of cadmium enrichment. The enrichment coefficient of the heavy metal cadmium of Amaranthus hypochondriacus L. was the highest. Amaranthus hypochondriacus L. has the strong enrichment ability to Cd, and is a good material for remediation of cadmium pollution in soil.

  Effects of Leaching by Alternate Flooding with Salty and Fresh Water on Coastal Saline Soil 2019, 35 (30):  124-128.  DOI: 10.11924/j.issn.1000-6850.casb18040122 Abstract + ( 458 )   PDF ( 1122KB )   ( 197 ) To investigate the effect of alternate flooding with salty and fresh water on improvement of coastal saline soil, a soil column simulation experiment was carried out to study the change of solution electrical conductivity, degree of mineralization and water consumption. The results showed that at the stage of flooding with salty water in treatment S-W, the changes of soil solution conductivity and total dissolved solid of effluent were similar to those in treatment CK. At the followed stage of flooding with fresh water in treatment S-W, the soil solution conductivity in different depths remained stable at the beginning, and then decreased rapidly and finally decreased slowly. Compared with the treatment of CK, the water saving rate of treatment S-W was 25.38%. Leaching by alternate flooding with salty and fresh water could improve the coastal saline soil and its potential of water saving is obvious, but the cost of time is more.

  Agricultural Flood Disasters in China: Spatial and Temporal Patterns Analysis 2019, 35 (30):  129-137.  DOI: 10.11924/j.issn.1000-6850.casb20190500096 Abstract + ( 498 )   PDF ( 1793KB )   ( 157 ) [Purpose] The purpose of this article is to find the flood disaster spatial distribution law in Mainland China. [Method] Based on the statistical data of the flood affected area from 1998 to 2017, the paper conducted the studies on agricultural flood disaster spatial distribution and dynamic change regularity of 31 provincial administrative regions by employing the methods of multi-year average, standard deviation and clustering analysis. [Result] The result indicated that the spatial and temporal distribution of flood disaster in China showed some regularity. In aspect of flood spatial distribution, the flood affected areas were mainly in northeast, east, and south of China which were the major agricultural areas in China as well. The provinces affected severely by flood were sparsely distributed; In terms of temporal distribution, occurrence of flood disasters showed a generally stable state in regular years but unusually severe in specific years; Mainland China is zoned into sub flood regions through cluster analysis in geographic region scale finally. [Conclusion] Flood disaster spatial distribution and dynamic change regularity were conducted based on historical statistical data, which can be referred by farmers and agricultural organisers.

  Flow Simulation Based on Unit Line for Data-missing Watershed 2019, 35 (30):  138-144.  DOI: 10.11924/j.issn.1000-6850.casb18040111 Abstract + ( 430 )   PDF ( 1507KB )   ( 158 ) According to the current situation of missing data in the rainfall runoff simulation process, different data-missing patterns were constructed based on the data-missing features of different rainfall types. Different interpolation methods were used to construct the unit line, and the popularization and application of unit lines under different missing patterns were discussed. The results showed that: the tail-fitting effect of the unit line constructed by different interpolation methods was better, and the interpolation effect to the peak was not good; there were deviations in the peak position after interpolation with different rainfall types; based on the peak deviation phenomenon and the principle of multiplication of unit lines, the fitting of the unit line after obtaining the peak value of the unit line was better, and it provided a new theoretical thinking for rainfall runoff simulation and agricultural non-point source evaluation simulation in the area of missing data, which had a good promotion significance.

  Research Progress of Maize Insect Resistance 2019, 35 (30):  145-149.  DOI: 10.11924/j.issn.1000-6850.casb18050080 Abstract + ( 422 )   PDF ( 1118KB )   ( 212 ) Corn is an important crop for grain, feed and industry. With the rapid development of bioenergy, stockbreeding and biopharmaceutical industries, the demand for corn in our country is increasing. Along with the acceleration of urbanization, rural labor force has been decreasing, which resulted in extensive field management and years of continuous cropping, and then the amount of corn insect pest appeared in an upward trend, the pesticides dosage was aggravated, and the yield and quality of maize was declined. In order to alleviate the corn pest and reduce pesticides dosage, this paper sum up the main types and hazards of corn pest, as well as the prevented measures and their advantages and disadvantages; it also presented an overview of screening and identification of domestic corn insect resistance, the research progress of corn insect-resistant genes and transgenic insect-resistant maize, which laid the theoretical foundation for China''s insect-resistant maize genetic breeding.

  The Relationship Between Japonica Rice of Different Panicle Types and the Occurrence of Rice False Smut 2019, 35 (30):  150-154.  DOI: 10.11924/j.issn.1000-6850.casb18050050 Abstract + ( 495 )   PDF ( 1266KB )   ( 128 ) In order to discuss the occurrence of rice false smut of different panicle types of japonica rice in Heilongjiang Province and its correlation with the disease, hole disease rate, spike disease rate, disease index, resistance frequency, spatial distribution of diseased grains and the characteristics of primary and secondary branches, etc. were investigated and analyzed by field natural susceptibility method. The results indicated that, different panicle type rices had different disease degrees, hole disease rate, spike disease rate and disease index of curved panicle type were the lowest, semi-straight panicle type was the second, and the straight panicle type was the highest, the occurrence of rice false smut was straight panicle type ＞ semi-straight panicle type ＞curved panicle type. 10.76% varieties of the curved panicle type showed immunity, 70.59% showed resistance, 52.13% of the semi-straight panicle type showed resistance and 19.62% of the straight panicle type showed resistance. The distribution of diseased grains in different panicle types of rice was different, the distribution of diseased grains in curved and semi-straight panicle rices were middle ＞ upper ＞ lower, and that of straight ear was middle > lower > upper, and the three kinds of panicle diseased grains are mainly grown on the secondary branches. Correlation analysis showed that the secondary branch number of straight panicle type was significantly positive correlated with disease index, the secondary branch length of semi-straight panicle varieties was significantly negatively correlated with disease index, and the number of secondary branch of straight panicle varieties was significantly positive correlated with disease index.

  Study on The Development of Modern Characteristic Agriculture in Yunnan Plateau 2019, 35 (30):  155-164.  DOI: 10.11924/j.issn.1000-6850.casb20190500128 Abstract + ( 553 )   PDF ( 1216KB )   ( 157 ) In order to further exert regional comparative advantages, accelerate the transformation and upgrading, make the characteristic agricultural industry economy in Yunnan Plateau bigger and stronger, the comprehensive benefit, structural characteristics, regional distribution, organizational system and productivity of the agricultural industry in Yunnan since 2012 were vertically summarized from the perspective of industrial economic, and the main problems existing such as the lower whole level, prominent structural constraints, single industrial function, missing stability support, insufficient management subjects, etc. were condensed also through the horizontal comparison of some principal indicators in two latitudes of the whole country and five provinces in southwest China. The authors considered that the production of bulk agricultural products on the basis of large-scale as grain, oil, etc. is not Yunnan''s advantage. Fully use of the diversification in natural, geographical, biological and cultural resource of low latitude plateau in Yunnan, the differentiated development strategy should be insisted on and strengthened. The modernization of agriculture in Yunnan with diversity, characteristics, quality, difference in time (season) and zone (climate) should be continued. The characteristic cash crops, mountain livestock and poultry with large space for value promotion, distinctive regional characteristics, high technical requirements, having a better foundation and development potential in Yunnan should be the key industries and points in optimizing agricultural structure and distribution, adjusting the agricultural support policies should focused on supporting business subjects, developing modern deep-processing industries of agricultural products, promoting the integration of primary, secondary and tertiary industries, expanding multiple functions, etc. in Yunnan Plateau, which could be as a reference for characteristic agricultural development in Yunnan and other areas.