To meet the need of early-orderly-strong emergence of potato seedlings during season connection, the application of mechanized production technology and yield stability under adverse climatic conditions, ‘Favorita’was chosen as the test material, and five biologicals based on beneficial bacteria and engineering bacteria extracts were selected as the seed dressing, and the multiple characters of potato were analyzed. The five biologicals could promote the germination of seed tuber and the growth of both bud and root, advance seedling emergence for 2-7 days, and increase the emergence rate 49 days after sowing for 3.33%-17.78% compared with the control group. The best two are the ramification of yeast nucleotides and VDAL, whose effect on germination and root growth of seed tuber are significantly better than that of the control. The bio-agent dressing could accelerate the recovery of plants as well as the development of tubers after frost, with a yield-increasing of 8.39%-24.03% than that of the control, showing different levels of yield-stability effect. Four biologicals including Duomadaohe, ramification of yeast nucleotides, Gentai and VDAL are beneficial in stable production after frost and drought, and could be selected as seed tuber dressing in potato cultivation.

To guarantee the emergence rate and production potential of sugar beet seed in field, it is necessary to test the seed vigor before planting and select the seed with high vigor for planting. The sugar beet seeds were aged by high temperature treatment, and then the intelligent detection model of seed vigor was constructed based on five near-infrared hyperspectral pretreatment methods: standard normal transformation (SNV), de-trending correction (DET), Savitzky-Golay smoothing (SG), first-order difference (1D) and second-order difference (2D), so as to obtain the predicted seed germination rate. The actual germination rate was obtained by germination test of aged beet seeds. The results show that the intelligent detection model established by the first-order differential pretreatment of sugar beet seeds has the best prediction performance, and its prediction accuracy could reach 91.92%. Comparing the actual germination rate of untreated sugar beet seeds with the prediction results of the intelligent model established by the first-order difference pretreatment method, it is found that the prediction accuracy of the model is 88.2%. It is concluded that the near infrared hyperspectral technology is a new method for rapid and nondestructive determination of crop seed vigor.

To further clarify pathogenic factor of potato late blight, we cloned the cysteine protease family gene in the secreted protein of Phytophthora infestans causing potato late blight and express in E. coli BL21. In this study, TA cloning method was used to extract total RNA of P. infestans XH05-5-4 of Yunnan, synthesize cDNA by reverse transcription and connect gene fragment to the vector after PCR amplification. Then we induced the expression of it in E. coli BL21. The full length of cysteine protease family gene is 1176 bp, containing 1077 bp open reading frame (ORF) encoding 387 amino acids. Predicted by bioinformatics analysis, its protein molecular weight is 41.671 KDa, isoelectric point is 4.88. After IPTG induced expression and SDS-PAGE identification, the protein expressed in the constructed prokaryotic expression vector is consistent with the expected protein. The results of biological activity examination show that potato leaves have necrosis and this symptom is similar to potato late blight. A cysteine protease family gene (GenBank Accession: KP938956, name: C1A-PH-SCH1) was cloned from P. infestans XH05-5-4 by TA cloning method. It is a papain enzyme subfamily gene by homology comparison, and the prokaryotic expression vector is successfully constructed and expressed in E. coli BL21. The symptom is similar to watery necrosis of potato late blight, therefore, it is speculated that C1A-PH-SCH1 is involved in the pathogenic process of potato late blight.

The purpose of the study is to identify the auxin response factor (ARF) gene family in Glycyrrhiza uralensis Fisch. and analyze their expression patterns under abiotic stress. G. Uralensis Fisch. was taken as the object. We identified the ARF gene family by bioinformatics tools, and analyzed the physicochemical properties of proteins, conserved motifs, gene structure, evolutionary relationships, cis-elements and expression profiles. 10 ARF genes (GuARFs) were identified. The length of these ARF proteins ranges from 301 to 945 amino acids and the relative molecular weight varies from 33.07 to 104.37 kDa, with PIs in the range of 5.93 to 8.50. Subcellular localization assays shows that the GuARF proteins are located in the nucleus. The conserved domain analysis indicates that most of GuARF proteins contain B3, Auxin_resp and Aux/IAA domain. Gene structure analysis reveals that the exon number of GuARF genes ranges from 6 to 22. There are 5 different types of cis-elements in the promoter region of GuARF genes. Phylogenetic analysis reveals that the GuARF proteins are clustered into 3 groups. RNA-seq data show that the expression level of 10 GuARF genes is different under abiotic stresses. The results indicate that the GuARF gene family may involve in multiple biological processes, and the study could provide valuable information for further research on physiological and molecular response of plants to abiotic stresses.

It aims to provide a basis for heterosis utilization and breeding of ornamental kale. Two male sterile lines and seven inbred lines were used as the female and male parents, respectively. 14 hybridized combinations were constructed by NCⅡ incomplete diallel cross method. The combining ability and heritability of seven traits were estimated, namely, plant height, outer leaf number, inner leaf number, outer leaf divergence, inner leaf divergence, the outer leaf shape index, and the inner leaf shape index. The results showed that the female parental line C6BZ was better than CD10 in inner leaf number and outer leaf divergence according to the value of the general combining ability. Meanwhile, the inbred lines HZ1631 and DFZ were both better than other five ones in the value of inner leaf number and outer- and inner-leaf divergence. Four superior hybridized combination CD10×DFZ, CD10×HZ1631, C6BZ×HZ1631 and C6BZ×F0819 were selected according to the specific combining ability. The broad-sense heritability of the seven traits were all higher than 50%. The narrow-sense heritability of the outer leaf index and inner leaf index were both higher than 50%, so the two traits could be selected in the earlier generation. Whereas, the other five traits should be selected in higher generation because of their low narrow-sense heritability. Based on the experiments, we acquired the results of the general and specific combining ability of two male sterile lines and seven inbred lines, and also got the broad-sense heritability and narrow-sense heritability of the seven significant ornamental traits in kale. It will benefit the breeding of ornamental kale under heterosis utilization.

Plant polysaccharide is a kind of natural active substance from a wide source. Because of its advantages of low toxicity and high activity, it has a broad prospect for development and utilization. However, the extraction method of polysaccharide is closely related to the extraction rate and biological activity of polysaccharide. In order to define the difference between polysaccharide extraction method and the polysaccharide extraction method, and the connection between the extraction yield and activity, in this paper, on the basis of a large number of literature, we summed up the advantages and disadvantages of different extraction methods of some polysaccharides, summarized polysaccharide extraction yield difference, analyzed the influence of the extraction methods on the biological activity of polysaccharide. It is concluded that different extracting methods themselves have certain advantages and disadvantages. As a result of the limitation of plant structure itself, different extraction methods have some effects on the extraction yield and structure. Selecting appropriate extraction method could improve the work efficiency, and provide a theoretical basis for guiding the extraction of polysaccharides.

The purpose of this review is to gain an in-depth understanding of the absorption mode and transport mechanism of sulfur in plants. The importance of sulfur to plants, the symptoms of plant sulfur deficiency and the mechanism of sulfur absorption and transport of plants in recent years are summarized. The study focuses on the transport mechanism and active process of sulfate, expounds that the process of sulfate entering the plant includes activation, reduction and cysteine synthesis. Research on the changes of sulfate in plant at home and abroad, and the utilization mechanism of various existing forms of sulfate are concluded. Overall, the study lists existing problems in the research field and discusses future research priorities.

To screen out the best substrate proportion which is suitable for the growth of C.companulata ‘Youkou’ container seedlings and improve the growth quality of Guiyang cherry blossom transplant container seedlings, peat, perlite, vermiculite, and yellow clay were used as the raw materials, and 4 mixed substrates were configured in certain proportions. The experiment set the yellow soil as the control, a 35 cm × 35 cm× 30 cm non-woven bag was selected as the seedling container, and the annual C.companulata ‘Youkou’ grafted seedlings introduced to Guiyang were tested to determine the physical and chemical properties of the soil, and the growth and physiological response of C.companulata ‘Youkou’ to different substrate proportions, and the correlations of the measurement indicators were analyzed. The results show that the mixed substrate has a smaller soil bulk density, greater porosity and strong sustainability of soil nutrients than the yellow soil, which is conducive to the plant seedling height, ground diameter and the accumulation of biomass; the mixed substrate could promote the formation of photosynthetic pigments in C.companulata ‘Youkou’, enhance photosynthetic efficiency and promote the accumulation of photosynthetic products, the physiological indicators are better than those of the yellow soil control. Correlation analysis shows that there is a strong correlation between the seedling height, ground diameter, biomass, chlorophyll content, actual light quanta, soluble sugar and soluble protein of the C.companulata ‘Youkou’. The experiment shows that T4 (peat soil: vermiculite: perlite: yellow soil=3:2:1:1) is the best substrate proportion for the cultivation of C.companulata ‘Youkou’ container seedlings introduced to Guiyang.

To reveal the physiological mechanism of leaf color change in Plantycladus orientalis cv. Semperourescens and to provide reference for the breeding and promotion of evergreen varieties in landscaping, the single individual of P. orientalis cv. Semperourescens, which is varietas of P. orientalis, was used as the test material, and the dynamic changes of leaf color, related pigment content and photosynthetic response characteristics of yellow leaves on the top of branches and green leaves at base during the growth period were studied. The results showed that from March to October, there was a dynamic change process of yellow-green-yellow in the yellow leaves of P. orientalis cv. Semperourescens, and a certain degree of greening in summer. In the same month, chlorophyll a (Chl a), chlorophyll b (Chl b), total chlorophyll (Chl) and carotenoid (Car) content in yellow leaves were significantly lower than those in green leaves, while, the ratio of Car to total chlorophyll (Car/Chl) content in yellow leaves was higher than that in green leaves. Chl contents first increased and then decreased both in yellow and green leaves, while Car contents first decreased, followed by a gentle change and then a sharp rise. In addition, the light saturation point of yellow leaves was lower than that of green leaves. The net photosynthetic rate (Pn) of yellow leaves was significantly lower than that of green leaves under the same light intensity. The photosynthetic index showed a trend of first increasing and then decreasing along with the time. Pn of yellow leaves from March to August were significantly lower than that of green leaves. Furthermore, there was a significantly positive correlation between photosynthetic index and Chl content, and a significantly negative correlation between photosynthetic index and Car/Chl content ratio. In conclusion, the yellow color of the leaves of P. orientalis cv. Semperourescens might be caused by the high ratio of Car/Chl content.

To explore the actual application effect of landscaping waste resource utilization products in landscaping and soil improvement, and promote the resource utilization of landscaping waste, in this experiment, organic fertilizer and biomass charcoal, which are the products of landscaping resource utilization, were used in the greening of urban parks. Loropetalum chinensis, Axonopus compressus, and Pennisetum purpurea were selected as shrubs and herbs in landscaping, to evaluate the application effect of landscaping waste resource utilization products by measuring the chlorophyll content, plant height and soil nutrients of plants in different treatments. The results show that the use of organic fertilizer and biochar could effectively increase the chlorophyll content of the three plants and promote plant growth. Organic fertilizers have different effects on the soil nutrient content of Loropetalum chinensis, but could improve the soil moisture content and electrical conductivity. In addition, organic fertilizer and biochar could significantly increase the soil nutrient content of A. compressus and Pennisetum purpurea, which are more conducive to plant growth. This experiment provides a theoretical basis for the application of landscaping waste resource utilization products in landscaping in terms of plant growth and soil nutrients, and at the same time lays a foundation for the resource utilization of landscaping waste. Subsequent research should be carried out on the physical, chemical and biological properties of the soil to further enrich the above theoretical basis.

To find out the spatial distribution characteristics and influencing factors of exchangeable magnesium content in cultivated soil in Sanming City, based on the test results and related data of 4833 soil samples, the spatial distribution characteristics and influencing factors of exchangeable magnesium content in cultivated land soil in Sanming City were analyzed by statistical and geographical statistical methods. The results showed that the exchangeable magnesium average content of cultivated land soil samples in Sanming City was at medium level, and the average value was 62.7 mg/kg. The difference of exchangeable magnesium average content in soil samples from different counties (cities or districts) reached significant level. The proportion of samples with deficiency exchangeable magnesium content and arable land with deficiency exchangeable magnesium content accounted for 44.15% and 40.72%, respectively. Except that the difference of exchangeable magnesium content by soil type grouping was not significant, the differences of the soil exchangeable magnesium content by the other influencing factors grouping were significant. Therefore, applying organic fertilizer, adjusting soil pH, improving sandy soil texture and supplementing magnesium fertilizer could be the main measures to control soil exchangeable magnesium content in Sanming City.

To further increase maize yield and improve a better environment condition in lime concrete black soil of Southern Henan, a 2-year field experiment was conducted to analyze the effects of conventional urea (CK), controlled release urea (CRU) and new-type urea containing biochar (BU), microelement (MU) and humic acid (HAU) on maize growth and nutrient absorption under the same fertilization rate. We also evaluated the changes of soil nitrate content and maize economic benefits under different new-type fertilizers. The results showed that the application of new-type fertilizers could increase maize grain yield compared with CK, by the range of 2.7%-10.9%. Among the new-type fertilizers, HAU had the highest increase rate (10.9%), followed by CRU (8.8%), but the increase rates under BU and MU were relatively low. Compared with CK, the number of grains per ear and 100-grain weight under HAU were increased by 9.7% and 9.2%, and the plant uptakes of nitrogen and phosphorus were increased by 20.6% and 27.5%, respectively, with a significant difference level; however, there was no significant difference in yield components or in nutrient uptakes between the other treatments and CK. Additionally, HAU significantly reduced the nitrate content at the 0-40 cm soil depth compared with CK, the nitrate contents were reduced by 26.4% and 32.4% at the 0-20 and 20-40 cm soil depths, respectively. The order of the output-input ratio among all treatments was HAU (2.14) > CRU (2.05) > MU (2.04) ≈ CK (2.04) > BU (2.03). Therefore, the application of humic acid urea could not only increase the maize yield and economic benefit, but also reduce the risk of nitrate pollution in soil, which has a broad application prospect in lime concrete black soil of Southern Henan.

To acquire the fractional vegetation cover (FVC) of maize on real-time, which could provide a scientific basis for maize growth monitoring, we took the image shot by the digital camera installed in automatic weather observation station as data sources, built FVC estimation models using 9 color vegetation indices of images (NDI, ExG, ExR, ExG-ExR, R-G, G-B, VEG, CIVE and (G-B)/|R-G|) extracted by employing image processing technologies. The results showed that these indices could estimate the FVC of maize effectively with high accuracy except the (G-B)/|R-G|, the vegetative (VEG) was the optimal color vegetation index for estimation of maize FVC. The model with VEG as variable had the highest estimation accuracy for maize FVC, with the highest coefficient of determination (R²), and lowest root mean square error (RMSE) and mean absolute error (MAE) of 0.993, 0.0270 and 0.0223, respectively. The method could be applied to the extraction of crop FVC effectively.

The objectives are to avoid the application of delayed or excessive pesticide, improve the control efficiency, and achieve precise control on potato late blight. The potato late blight forecast model of CARAH, NEGFRY model of Denmark, and conventional control of applying fungicide were combined and used in field plot experiment. The control effect and economic benefit were analyzed by investigating the occurrence of potato late blight, and the role of CARAH model on potato late blight control was evaluated. The results showed that the fitting degree of the disease warning of CM was 93% compared with the actual disease occurrence. Using the CM, the application times of fungicides were reduced 1-3 times, the yield loss was reduced by 48.47%, the commercial potato rate was increased by 12.63%, the diseased potato rate was decreased by 4.43%, and the economic benefit was increased by 10966 yuan/hm². Therefore, the establishment of CARAH model of potato late blight in Heilongjiang Province could guide the prevention and control of potato late blight in Heilongjiang Province, reduce the unnecessary application of fungicide, and achieve the effect of precise treatment and target of reduction chemicals.

Soil connects the above-ground and underground ecosystems. Soil microorganisms play a key role in soil nutrient cycling and crop nutrient absorption from soil, which are considered as indicators of soil quality. Soil microorganisms can promote nutrient recycling and regulate plant growth and development by decomposing soil organic matter. With the variation of cropping structure in modern agriculture, especially in application of some planting patterns, adversity crop species on the above ground often affect the structure and diversity of soil microorganisms’ community, which further promote/retard crop growth and development, and have an impact on the occurrence of crop pests and crop production. In this paper, we reviewed the relationship among main planting patterns of crops in modern agriculture, soil environment and pest occurrence in farmland, highlighted the importance of scientific and reasonable selection of planting patterns, and discussed some key problems for further study of these planting patterns in agriculture practice.

In order to establish a simple, rapid and accurate method for detecting African swine fever virus, in this study a pair of specific primers were designed according to the p72 gene sequence of ASFV published in GenBank, and the appropriate bases in the primers were modified with locked nucleic acid. By optimizing the annealing temperature and the primers concentration, a PCR method with LNA modified primers for detecting ASFV was established. The results show that this method is highly sensitive and specific, and the sensitivity can reach 3×10¹ copies/uL, which is 100 times higher than that of PCR with conventional primers and 10 times higher than that of real-time PCR. The method has no amplification of the genomes of classical swine fever virus, porcine circovirus type 2 and pseudorabies virus, with good specificity. The results of 72 clinical samples are consistent with the results of qPCR recommended by OIE, and the coincidence rate is 100%. In this study, a LNA primer PCR method for detecting ASFV is established, with high specificity, sensitivity and simple operation, providing a novel, sensitive and specific detection technique for the detection of ASFV.

To investigate the effect of rare earth element lanthanum on osmotic regulation of navel orange leaves, the two-year-old ‘Newhall’ navel orange trees were used as the test material, and 0 mg/L (CK), 50 mg/L, 150 mg/L and 300 mg/L lanthanum nitrate solutions were sprayed on the navel orange leaves. Subsequently, the young leaves of the middle and upper part of the plant were collected at 0 h, 2 h, 4 h, 8 h, 12 h and 24 h after spraying. Finally, the content of soluble sugar, soluble protein and free proline in the samples were determined. The results showed that the soluble protein content in navel orange leaves (CK) increased first and then decreased at different growth time, while the content of soluble sugar and free proline continued to decrease. The accumulation trend of free proline content in navel orange leaves changed after spraying lanthanum nitrate solution with different concentrations. When the concentration of lanthanum nitrate was 50 mg/L and 150 mg/L, the accumulation of soluble sugar, soluble protein and free proline in navel orange leaves were promoted simultaneously. When the spraying concentration was increased to 300 mg/L, the accumulation of soluble sugar and free proline content in leaves was significantly higher than that of other treatments, but the accumulation of soluble protein content was significantly inhibited. Therefore, it could be concluded that navel orange leaves could adapt to regulate cell osmotic stress by actively accumulating soluble sugar, soluble protein and free proline after spraying lanthanum nitrate. Due to the varieties of osmotic substances, the appropriate concentration that promotes its content accumulation is different, wherein the appropriate concentration of soluble protein content accumulation is ≤ 150 mg/L, and the appropriate concentration of soluble sugar and free proline content accumulation is ≥ 300 mg/L. The results could provide reference for further research on the functional mechanism of rare earth elements on osmotic substances and the regulation of physiological metabolism.

In order to solve the resource waste and environmental pollution caused by Agaricus bisporus residue, the effect of Agaricus bisporus residue application on amino acid content of waxy corn was studied. Using Agaricus bisporus residue as fertilizer, the effects of Agaricus bisporus residue application on amino acid content in fresh grains of ‘Jinnuo 18’ and ‘Jinnuo 20’ were analyzed. The results showed that with the application of Agaricus bisporus residue, the content of amino acids in fresh grains of ‘Jinnuo 18’ and ‘Jinnuo 20’ increased compared with the control group. The increase of amino acids in different varieties was different, ranging from 2.94% to 13.11%, indicating that Agaricus bisporus residue as fertilizer is beneficial to the increase of amino acid content in fresh grains of waxy corn.

The key to instant cereal products is their dispersion and viscosity in water. In this study, taking the eleusine coracana as the material, we explored the process techniques of making Eleusine coracana cereal, aiming to provide references for cereal products of other starch crops. By means of pre-test, single-factor tests and L9 (3³) orthogonal tests, the formula and process combination of eleusine coracana powder, maltodextrin, glycerol monostearate and sugar were carried out by fuzzy comprehensive evaluation method. The best process and formula of the cereal are: glutinous rice flour 30 g, millet 12 g, sugar 10 g, black rice 10 g, maltodextrin 10%, glycerol monostearate 0.5%. The products have uniform color, smooth, sweet and delicious taste, and good brewing property.

Accurate and timely monitoring of crop drought conditions can provide strategies for responding to crop disasters and crop losses, and against financial loss. The study took Heilongjiang Province, a major agricultural province in China, as the research area. Based on the temperature vegetation dryness index (TVDI), with high sensitivity and precision, the study monitored the drought degree and spatial and temporal pattern in the growth period of dry crop. Savitzky-Golay (S-G) filter method was selected to remove normalized difference vegetation index (NDVI) and land surface temperature (LST) noise, then the TVDI was calculated from the re-created NDVI and LST data. Combined with local meteorological data and soil moisture data observed simultaneously in field, the TVDI was verified quantitatively. The results show that: NDVI-LST feature space established in this paper accords with triangular relationship, which is consistent with the previous research results. TVDI has significant negative correlation with surface soil moisture in different growth stages, and it shows that TVDI has the ability to reflect the dry and wet conditions of soil. Based on the TVDI drought classification grade results, drought occurs in each period of dry crop growth period in 2017, and the frequency and range of drought in western are higher than that in eastern Heilongjiang Province. At the beginning of sowing season, spring drought is more serious in the western part of Heilongjiang, especially in Qiqihar City. In early July, the influence of drought on the western part of Heilongjiang is alleviated,and the impact of the drought is gradually shrinking. The correctness rate of drought grade between TVDI and soil moisture is relatively high, and the consistency of the correctness rate basically reaches 90%. In conclusion, the TVDI index constructed based on MODIS data can reflect the agricultural drought in Heilongjiang Province. Our study can provide a basis for agricultural drought monitoring, as well as scientific reference for drought relief in Heilongjiang Province.

To provide technical parameters for the research and improvement of fish pump, the damage comprehensive evaluation method of vacuum fish pump was established by means of Principal Component Analysis (PCA). Experiments on Carassius auratus were carried out by vacuum fish pump to obtain fish body damage data. A comprehensive injury evaluation model was established by measuring the injured surface area ratio, 24-hour survival rate, red blood cell number, white blood cell number, superoxide dismutase activity, alanine aminotransferase activity and creatinine content. The results showed that the cumulative contribution rate of three principal components extracted by PCA was 78.232%, which could represent most of the fish damage. The comprehensive evaluation model of fish damage by vacuum fish pump was F=0.285X₁+0.111X₂+0.316X₃+0.366X₄-0.118X₅+0.234X₆. There was no significant damage to the surface and viscera of fish by vacuum fish pump, and the comprehensive score was -0.102, which was close to that of the control group, indicating that the damage effect of vacuum fish pump on fish was very small. The results of experiments show that SOD activity, white blood cell count and body surface damage area ratio are the data indexes that have great influence on damage evaluation. The comprehensive damage evaluation model established by PCA can be used as a feasible method to evaluate the damage of fish, which provides a powerful reference for the improvement of fish suction pump.

It is a worldwide problem to improve the utilization rate of water resources and solve the shortage of agricultural water. How to reduce the irrigation water consumption and optimize the water consumption structure while ensuring the grain production capacity in the main rice producing areas in Inner Mongolia could be regarded as a research hotspot. Based on the principle of water balance, the experiment of aerobic rice under mulched drip irrigation was carried out in Jalaid Banner, eastern Inner Mongolia from May to September 2018- 2019. Taking the traditional rice transplanting mode as a reference, this paper explored the crop water requirements of mulched drip irrigation rice in different growth stages in typical planting areas of eastern Inner Mongolia, and analyzed the final yield and crop water requirement coefficient of rice under different irrigation methods. The results showed that the water requirement of rice under mulched drip irrigation was 608.4 mm in the whole growth period. When the soil moisture content was 85%-100% of the saturated water content in the growth stage, the yield was the highest. Water requirement was the minimum at seedling stage and the maximum at heading and filling stage. The maximum water consumption intensity was in the middle stage of jointing and booting, and the maximum water demand coefficient was at heading and filling stage in the whole growth period.

To explore the water consumption regularity and crop coefficient of open-field lettuce in summer and autumn in central Yunnan, and provide irrigation guarantee for lettuce production in this region, water consumption tests of lettuce in summer and autumn were carried out in the field at the Irrigation Experimental Center Station of Yunnan Province in 2019. The water consumption law and crop coefficient of lettuce in summer and autumn were calculated by using water balance and Penman-Monteith formula, and the influencing factors of water consumption were analyzed by path analysis. The results showed that the water consumption during the whole growth period of lettuce in summer and autumn was 76.47 and 44.54 mm respectively, the daily water consumption intensity at the seedling stage, lotus seat stage, balling stage and mature picking stage of summer lettuce was 0.74, 1.23, 2.26 and 2.52 mm respectively, and those of autumn lettuce was 0.40, 0.73, 0.86 and 1.15 mm respectively. The crop coefficient of summer lettuce in each growth period was 0.17, 0.31, 0.74 and 0.75 respectively, while that of autumn lettuce in each growth period was 0.18, 0.25, 0.37 and 0.81 respectively. The main influencing factors of water consumption of lettuce in summer were the average soil temperature of 0-40 cm and rainfall, while the main influencing factors of water consumption of lettuce in autumn were the average soil moisture content of 0-40 cm and sunshine hours. The coefficient of lettuce crop in summer and autumn was obtained, which could provide a basis for the formulation of irrigation quota and irrigation schedule of lettuce in central Yunnan.

Grain production is a strategic industry to stabilize people and secure the nation. Guangdong Province is the largest grain consumption region in China, and it is of practical significance to stabilize its grain production and ensure food security. Firstly, the study sorted out the basic situation of grain production in Guangdong, from 2010 to 2019, its grain yield and planting area were slightly decreased. Secondly, the study analyzed the restricting factors on grain production capacity of Guangdong, including the small scale of agricultural production, high cost of grain production, low economic benefit of grain production, prominent planting structure problems and low potential of agricultural mechanization. Finally, countermeasures were put forward from seven aspects, such as replanting abandoned arable land, adjusting planting structure, improving production capacity, thus providing useful references for stabilizing and improving the grain production capacity of the province.