In order to clarify the differences in the yield and nitrogen uptake of early-late season double-cropping rice between early and late seasons in South China, six early-late season double-cropping rice cultivars were planted in early and late seasons according to local high-yield cultivation measures to determine the yield, yield components, dry matter accumulation, nitrogen uptake, etc. The yield of early-late season double-cropping rice were 6.68-7.91 t/hm² and 5.72-6.11 t/hm² planted in early and late season, respectively. The yield in early season was significantly higher than that in late season, with an average increase of 1.53 t/hm². Correlation analysis showed that the higher grain yield in early season was related to the increase in the panicle number and grain weight. There were significant differences in dry matter accumulation and nitrogen uptake between early and late seasons. The dry matter accumulation and nitrogen uptake in early season was increased by 25.0% and 29.5%, respectively, compared to those in late season. In addition, the grain yield of early-late season double-cropping rice were significantly positively correlated with the dry matter accumulation and nitrogen uptake. Early-late season double-cropping rice had higher grain yield, dry matter production and nitrogen uptake capacity when planted in early season. These results provide a theoretical basis for the high-yield cultivation of early-late season double-cropping rice in South China.

To investigate the causes of the phenomenon of grain weight heterosis in maize, the number and size of endosperm cells in maize grains were studied. Maize varieties ‘Zhengdan 958’ and ‘Xianyu 335’ and their parents served as experimental materials for analyzing the heterosis relationship between hybrid and parents of grain weight, endosperm cell number and area. The results showed that the mid-parent heterosis of the endosperm number of ‘Xianyu 335’ and ‘Zhengdan 958’ was 40.81% and 36.03%, and the over-parent heterosis was 33.09% and 23.82%, respectively. The mid-parent heterosis of 100-grain weight of ‘Xianyu 335’ and ‘Zhengdan 958’ was 27.22% and 28.89%, and the over-parent heterosis was 19.72% and 18.34%, respectively. However, the mid-parent heterosis of endosperm cell area of ‘Xianyu 335’ and ‘Zhengdan 958’ was -44.42% and -24.79%, and the over-parent heterosis was -45.75% and -37.30%, respectively. The endosperm cell number was positively correlated with the grain weight, and the correlation coefficient was 0.796. In summary, the number of endosperm cells of the maize hybrid is more than that of their parents, which is the main reason for heterosis of grain weight. Selecting the inbred lines with large number of endosperm cells can effectively increase the grain weight of the hybrid in the hybrid combinations.

In order to explore the combined application amount of micro-fertilizer for high-quality and high-yield potato in the arid agricultural area of Longzhong, the effects of iron and zinc fertilizer on potato yield, quality and soil nutrient were studied. The two-factor random block design was adopted, with zinc and iron fertilizer as the test factors, and three fertilization levels were set for zinc and iron fertilizer, namely: zinc fertilizer (0, 20, 40 kg/hm²) and iron fertilizer (0, 10, 20 kg/hm²), a total of 9 treatments. The results showed that single application of iron and zinc fertilizer and their interaction had significant effects on potato yield, quality and soil available zinc and iron content (P<0.05). Among them, the yields of Fe2Zn0 and Fe0Zn2 increased by 15.0% and 19.5% compared with Fe0Zn0, and the yield of Fe2Zn2 increased by 21.5% compared with Fe0Zn0. Fe2Zn0 increased the iron content by 12.4% compared with Fe0Zn0, and the zinc and iron content of Fe0Zn2 increased by 10.8% and 9.8% compared with Fe0Zn0. The yield, starch, iron and zinc content of Fe2Zn2 were significantly increased by 21.5%, 3.4%, 17.3% and 13.6% compared with Fe0Zn0, respectively. In the 0-10 and 10-30 cm soil layers, the available iron content of Fe2Zn0 was significantly increased by 15.0% and 4.0% compared with Fe0Zn0, the available zinc content of Fe2Zn2 was significantly increased by 104.2% and 42.9% compared with Fe0Zn0. Considering comprehensively, under the conditions of this experiment, the single application rates of iron and zinc micro-fertilizer were 20 kg/hm² and 40 kg/hm², respectively, and the combined application rate of iron fertilizer was 20 kg/hm² and zinc fertilizer 40 kg/hm² had the best effect, which was conducive to improving potato quality and increasing yield.

To assess the impact of varying erythritol levels on seed germination and to provide a foundation for selecting sugar beet seed coating, the seeds of sugar beet 'TD801' were used as the test material in this study. The three concentration gradients (5, 7.5, 10 mmol/L) and three hour time gradients (8, 16, and 24 h) were set up, and then 9 treatments were used to determined the indexes. The germination potential was increased by 4%-12.33% in comparison to the control CK; the rate of germination was raised by 9%-12% compared to the control CK; and the germination index was also augmented by 28.92%- 60.74% compared with the control CK; the vitality index was increased by 69.45%-116.81% compared with the control CK; and the relative electrical conductivity was decreased by 58.26%-83.10% compared with the control CK. When the concentration was 5 mmol/L for 8 h, it had a better effect on improving germination potential; when the concentration was 5 mmol/L for 24 h, the effect of germination rate was better; when the concentration was 5 mmol/L for 16 h, it had a better effect on germination index and vitality index; when the concentration was 10 mmol/L for 24 h, it had a better effect on the relative electrical conductivity. The 9 treatments had the effect of promoting the initiation of sugar beet seeds, and a greater overall effect on seed germination of sugar beet was observed when the concentration of erythritol solution was 5 mmol/L for 16 hours.

To fully utilize the land resources and explore environmentally friendly, high-yield, and efficient cotton-sorghum intercropping systems, we conducted an experiment with sorghum and cotton intercropped by 'Jiliang 2' and 'Lu 6269' in Binzhou City, Shandong Province. Four intercropping patterns were adapted to analyze their effects on cotton agronomic traits, soil nutrient content, yield components, yield and economic benefits. The results showed that cotton-sorghum intercropping, compared with cotton monoculture, significantly increased cotton plant height, the number of fruiting branches and boll numbers, resulting in 0.73% to 6.13% increase in lint yield. Although fiber quality was decreased slightly, the soil available nutrient content was enhanced significantly. Among the three intercropping systems, the highest yield and economic benefits were observed in the one with 4-row cotton and 4-row sorghum. The lint yield in this pattern was 6.13% higher than that of cotton monoculture, and the economic benefits increased by 13.79%. Therefore, this pattern could be used in this area in order to improve yield potential in sorghum-cotton intercropping systems.

The study was to assess the effects of acidic soil amendments applied in combination with foliar potassium fertilizers on agronomic traits, yield and quality of Nicotiana tabacum L.. Acidic soil amendments alone and in combination with different types of foliar potassium fertilizers (potassium sulphate, potassium dihydrogen phosphate and potassium magnesium sulphate) spray application were analyzed in a field experiment. The results showed that acidic soil amendments significantly improved agronomic traits and enhanced yield of tobacco plants. On the basis of acidic soil amendments application, foliar spraying of potash fertilizer further promoted early ripening and yellowing of tobacco leaves, and increased the proportion of upper medium tobacco leaves, with potassium sulfate and potassium dihydrogen phosphate treatments having the most obvious effects. In terms of tobacco quality, potassium sulfate spraying significantly improved the appearance quality of tobacco, while the potassium dihydrogen phosphate treatment performed better on harmonization of chemical compositions. In addition, potassium magnesium sulfate spraying significantly increased the total sugar and reducing sugar contents of the tobacco leaves. The analysis of potassium content showed that C3F grade tobacco was significantly enhanced, while the enhancement of B2F grade was smaller. In summary, the reasonable combination of acidic soil amendments and foliar potassium fertilizer application can effectively improve the yield and quality of tobacco leaves, providing an important fertilizer management strategy for flue-cured tobacco production.

Low temperature freezing damage is the main disaster of late maturing citrus in Nanchong. Based on frozen injury experiments and historical disaster data from the agricultural department, combined with the hourly temperature situation of the National Meteorological Monitoring Station, the threshold of low-temperature freezing injury indicators was studied using probability regression and information diffusion theory methods during the winter period under the conditions of no cloud or less cloud sky, the daily temperature range ≥8℃, and the minimum temperature ≤3℃. The results showed that the linear regression relationship between the meteorological temperature established for the two experimental orchards and the measured temperature was statistically tested. When the meteorological temperature was 1.7℃ in Xichong and 2.6℃ in Jialing, the measured temperature of the orchards would reach -2℃, and frost damage began to occur; Based on the current refined weather prediction capability, a composite index threshold system based on the maximum duration (hours), total duration (hours), and total days of low-temperature freezing damage days during a sliding two week period was established. Four frozen damage samples were selected for testing, and the results showed that the frost damage index rating was in good agreement with the measured frost damage level, which had good practical application value.

In order to investigate the effects of different wavelengths of LEDs light sources on the growth of tartary buckwheat sprouts, red (R), blue (B) and green (G) LEDs were used to culture the sprouts, with the darkness as a control. The indicators including morphological growth, bioactive matter accumulation, key gene expression involved in flavonoid synthesis, and antioxidant activity were determined, respectively. The results showed that the hypocotyls of tartary buckwheat sprouts under B were deep red and the hypocotyl elongation was strongly inhibited. The accumulation of anthocyanins, total flavonoids and total phenols under B were the highest, which were 7.18, 2.96 and 2.49 times as that of D, respectively. The hypocotyl of tartary buckwheat sprouts under R showed a light pink color. The accumulation of the above three bioactive substances under R was also significantly higher than that of the control, which was 2.56, 1.68 and 1.40 times, respectively. The hypocotyl elongation of the sprouts under G was similar to that of R, but the appearance was transparent and white. The accumulation of bioactive matters under G was not significantly different from that of the control. Both B and R strongly induced the expression of key genes involved in flavonoid biosynthesis pathway, and significantly increased the antioxidant activity of the hypocotyls of tartary buckwheat sprouts. In conclusion, red and blue LEDs could significantly affect the morphological growth of tartary buckwheat sprouts, and increase the accumulation of bioactive substances as well as the antioxidant capacity. Meanwhile B treatment was recommended due to the best performance.

The study was conducted to investigate the effect of lime application on the cadmium (Cd) content in grains of double rice in a clean and acidic paddy field (soil pH 5.2, soil Cd content 0.2 mg/kg). Four treatments were set up to measure the cadmium contents in rice grains. The treatments were as following: (1) straw removal without liming as control, (2) straw removal with lime application, (3) straw returning every season without liming, (4) straw returning combined with liming. The results showed that lime application significantly reduced the Cd content in brown rice in the early and late rice season except that in the late rice season in 2020. Straw returning had no significant effects on the Cd content in brown rice. There were interactive effects between liming and straw returning on the Cd content in brown rice in the early rice season in 2020. Lime application reduced the Cd content in brown rice by 61.0% under straw returning and by 38.0% under straw removal in the early rice season in 2020. Lime application significantly reduced the Cd content in polished rice in both the early and late rice seasons in 2019. Straw returning significantly increased the Cd content in polished rice in the late rice season in 2020. There were interactive effects between liming and straw returning on the Cd content in polished rice in the late rice season in 2020. Lime application reduced the Cd content in polished rice by 38.1% under straw returning, while only by 4.2% under straw removal in the late rice season in 2020. Therefore, lime application can not only reduce the Cd content in rice grains, but alleviate the risk of Cd pollution caused by straw returning in the clean and acidic paddy field, thereby contributing to food safety.

To explore the role of soil enzymes and pH in the degradation of tetracycline in Microbial Electrochemical Systems (MES), four types of soils including black soil, moisture soil, yellow brown soil and red soil were collected for study. The results showed that after adding tetracycline (TN treatment, 10 mg/kg) to black soil, moisture soil and red soil, the values of pH increased by 0.08, 0.15 and 1.09 units respectively compared with the control treatment (CK, without tetracycline addition). However, in MES treatment (TC, tetracycline concentration 10 mg/kg), the values of pH in the four types of soil all showed downward trend. Although the soil dehydrogenase, urease and polyphenol oxidase activities exhibited different variation trends in tetracycline contaminated soil, their activities in MES increased by 62.4%-72.1%, 11.3%-80.9% (except red soil) and 12.6%-42.6% compared with TN treatment, respectively. Meanwhile, the degradation rate of tetracycline in TC treatment was respectively increased by 14% (black soil), 26% (moisture soil), 26% (yellow brown soil) and 17% (red soil) compared with TN treatment. Correlation analysis indicated that dehydrogenase activity showed significant positive correlation with tetracycline degradation rate, while pH showed significant negative correlation with degradation rate, indicating that dehydrogenase might participate in the process of tetracycline degradation, and acidic conditions may be more conducive to degradation. This experiment revealed the degradation mechanism of tetracycline by MES based on soil biochemical characteristics, which could provide important support for soil pollution remediation.

To further understand the soil water characteristics of different vegetation types on the Loess Plateau, 7 plots of 5 typical vegetation types including Caragana korshinskii 1, Caragana korshinskii 2, grassland 1, grassland 2, Pinus sylvestris, Hippophae rhammoides, and apricot were selected as the research objects in Daliuta Town, Shenmu City, Yulin City, Shaanxi Province. Single factor analysis of variance was used to compare the differences of soil water in different sites. The results showed that: (1) in the 0-100 cm soil layer, there were significant differences in soil water content and soil water storage among different vegetation types (P<0.05), with the order of apricot tree>Hippophae rhammoides>Caragana korshinskii 1>Caragana korshinskii 2>grassland 1>Pinus sylvestris>grassland 2. (2) Soil moisture content of different vegetation types increased with the increase of soil depth. The change trend of grassland 1, Pinus sylvestris and grassland 2 was not obvious. (3) Soil water storage of different vegetation types showed an increasing trend as a whole with the increase of soil depth. The water storage capacity of each vegetation was relatively small in 0-40 cm soil layer and had little change; it changed greatly in the 40-100 cm soil layer and reached the maximum in the 80-100 cm soil layer. The experiment analyzed the characteristics of soil water content and soil water storage under different vegetation types, which provided theoretical basis for the subsequent soil and water conservation, vegetation restoration and ecological environment construction in this region.

In order to explore the biological function of PBP gene in transgenic tobaccos and select the low arsenic (As) accumulation parent tobacco germplasm, taking T₂ generation seeds of transgenic tobacco with PBP gene and wild-type tobacco (Nicotiana tabacum K326) seeds as materials, Real-time PCR was used to study the spatial and temporal expression profile of exogenous PBP in transgenic tobaccos, and the activities of antioxidant enzymes (AOEs) in transgenic tobacco lines under As stress were also determined. AOEs activity showed that SOD and POD activities reached the maximum value of 80.25 U/g and 152.02 U/g in CK plants at 5 d after As stress, which were significantly higher than those in transgenic plants. Also, H₂O₂ and MDA contents in CK plants were significantly higher than those in transgenic plants at the later stage of As stress (3-5 d). Additionally, at 7 d and 14 d after stress, the content of As in transgenic tobacco plants was significantly reduced. Based on the expression profiling of ion transporter genes, the results showed that As stress not only induced significant up-regulation of PBP in transgenic plants, but also caused significant up-regulation of channel protein genes such as HAK1 and PHT4 in transgenic and CK plants, and the average expression levels of HAK1 and PHT4 in CK were 1.5 and 3.75 times of that in transgenic plants. The introduction of exogenous PBP gene can effectively reduce the accumulation of As in transgenic tobaccos.

In order to provide new treatment methods and strategies for clinical prevention and treatment of Pseudomonas aeruginosa infection, the inherent resistance, acquired resistance and adaptive resistance of Pseudomonas aeruginosa are summarized in this paper. With the mechanisms of different resistance, the characteristics, development trends and treatment methods of Pseudomonas aeruginosa resistance under different situations are also analyzed. This paper points out that Pseudomonas aeruginosa resistance mainly depends on its high level of inherent and acquired resistance, while its adaptive resistance mainly depends on the formation of biofilm mediation and quorum sensing. It is proposed that clinical Pseudomonas aeruginosa resistance is not the result of a single resistance. In all, the most effective treatment strategy in the future is to carry out combination therapy based on traditional treatment and new treatment.

To investigate the effect of exogenous addition of Vitamin B12 (VB₁₂) on the production of 3-hydroxypropionic acid (3-HP) through glycerol reduction pathway in Klebsiella pneumoniae HD79 and K. pneumoniae HD79-T, and to explore the threshold upper limit of VB₁₂ on the above strains, different concentrations (0.01, 0.02, 0.03, 0.04, and 0.05 g/L) of VB₁₂ were added to the fermentation medium of K. pneumoniae HD79 and K. pneumoniae HD79-T. The consumption of substrates and production of products were detected by HPLC, mRNA expression of genes related to the reduction pathway was detected by qRT-PCR, and enzyme activities related to metabolism were detected by enzyme-linked immunosorbent assay (ELISA). The results showed that the thresholds of VB₁₂ for K. pneumoniae HD79 and K. pneumoniae HD79-T was 0.01 g/L and 0.03 g/L, respectively. Compared with the absence of VB₁₂, the productions of 3-HP of K. pneumoniae HD79 and K. pneumoniae HD79-T were increased by 24.39% and 8.86%, respectively; the expression levels of aldehyde dehydrogenase gene puuC were increased by 2.49-fold and 1.68-fold, respectively; the enzyme activities of ALDH, GDHt, and PDOR increased by 50.24%, 40.36%, and 18.29% in K. pneumoniaeHD79, and by 30.49%, 37.84%, and 13.56% in K. pneumoniae HD79-T, respectively. These results indicated that exogenous addition of coenzyme factor VB₁₂ was a feasible strategy for high production of 3-HP in Klebsiella pneumoniae.

With the intensification of global climate change and land salinization, improving the ability of rice (Oryza sativa L.) to grow in saline and alkaline environments has become a key challenge for agricultural production. The realization of the strategy of " the adaptation of germplasm to land " requires a deep understanding of the salt tolerance mechanism of rice, then breeding improvement on this basis. In this study, we summarized the recent research results on salt tolerance regulatory genes in rice, and classified them functionally according to the biological processes involved. The perception of salt stress in rice and the subsequent activation of various physiological regulatory mechanisms, including osmotic regulation, ion homeostasis, antioxidant defense system and nutrient balance, were analyzed in detail. In this review, we focus on several key Salt stress signaling pathways in rice, including the SOS (Salt Overly Sensitive) pathway, MAPK (Mitogen-Activated Protein Kinase) cascade pathway and hormone regulatory pathway. These pathways play crucial roles in rice adaptation salt stress environment. By reviewing the existing literature, this review aims to provide a comprehensive overview of the salt tolerance regulatory genes and their functions in rice, provide scientific basis on breeding salt-tolerant rice on these grounds, and as a reference in improving the yield and quality of rice under saline and alkaline environments.

Dry direct seeding is an important future direction of rice production with a large area in South Asia and Southeast Asia of Indica rice growing regions. However, Japonica rice planting in tropical and subtropical areas mostly adopts traditional transplanting method. Mesocotyl length (ML) is an important factor affecting the emergence and vigor of rice seedlings in dry direct seeding. Breeding long mesocotyl germplasm based on molecular marker assisted selection (MAS) is the most economical and efficient way to promote the popularization of rice direct seeding. So far, four rice mesocotyl elongation genes have been cloned and reported, namely OsGSK2, GY1, OsPAO5 and OsSMAX1, respectively. In this study, we selected the TROP and TEMP Japonica rice subpopulations originated from the 3K re-sequencing project for analysis, determined the length of mesocotyl and identified superior haplotypes of OsGSK2, GY1, OsPAO5 and OsSMAX1. The results showed that the ML of TROP and TEMP populations presented a typical continuous normal distribution. OsGSK2, GY1, OsPAO5 and OsSMAX1 include 3, 3, 3 and 6 haplotypes, respectively. The frequency of haplotype distribution was different in TROP and TEMP panels for the same gene. OsGSK2-Hap1, GY1-Hap2, OsPAO5-Hap3, OsSMAx1-Hap2 and OsSMAx-Hap3 were identified as superior genes in TROP panel; whereas superior haplotypes OsGSK2-Hap1, OsPAO5-Hap2 and OsSMAX1-Hap2 were identified in TEMP panel. In addition, the seedling height for superior haplotype accessions was higher than that of un-superior haplotype accessions in the TROP and TEMP panels, which was easy to form a growth advantage in growth. The superior haplotypes identified showed significant additive effects in TROP and TEMP panels, which could be used in MAS breeding. This study provides reference for the breeding of direct seeding Japonica rice in different regions, and promotes the rapid popularization of dry direct seeding technology.

In order to explore the effects of different sulfur levels on the key enzyme activities in carbon and nitrogen metabolism in soybean leaves at seedling and flowering stages, soybean varieties ‘Laidou 2’ and ‘Hefeng 55’ were used as test materials. The data of key enzyme activities of carbon metabolism in soybean leaves at seedling and flowering stages were measured by watering nutrient solution. The GOGAT and SS enzyme activities of ‘Laidou 2’ and ‘Hefeng 55’ reached the maximum under 160 mg/L treatment. The peak value of GS enzyme activity of ‘Laidou 2’ was the strongest under 160 mg/L treatment, the peak value of ‘Hefeng 55’ in seedling stage was the highest under 260 mg/L treatment, and the peak value in flowering stage was the lowest under 20 mg/L treatment of sulfur nutrition. The SPS enzyme activity of ‘Laidou 2’ reached the maximum value under 40 mg/L treatment, while the peak value of ‘Hefeng 55’ at seedling stage was under 80 mg/L treatment with higher sulfur nutrition, and the peak value at flowering stage was under 260 mg/L treatment with the highest sulfur level. The results showed that the activities of glutamate synthase (GOGAT), glutamine synthetase (GS), sucrose phosphate synthase (SPS) and sucrose synthase (SS) at flowering stage were significantly higher than those at seedling stage, and the same rule was found among varieties.

To identify the pathogen species causing a noval desease of leaf spot and stem spot of Houttuynia cordata Thunb. in Guanghan City, Sichuan Province, and provides theoretical basis for the scientific management of this disease, the leaves and stems of diseased H. cordata were collected from Guanghan City, and the pathogen was isolated and identified by tissue isolation, pathogenicity testing, morphological characterization, and molecular identification based on ITS, tef1, cal and his3 gene sequences. The results indicate that the mycelium of the pathogen is gray-white to light brown. The conidiomata, which are produced in the late growth stage, can produce two types of conidia: fusiform to oval-shaped α-type conidia and filamentous or hook-shaped β-type conidia. Multiple gene cluster analysis showed that the pathogen formed an individual branch adjacent to the Diaporthe Sojae and D. phaseolorum branches, and formed a big branch with these two branches in the phylogenetic tree, and a new species named D. houttuynia was suggested to establish to accommodate this pathogen. According to morphology and molecular identification, the pathogen causing the noval desease of leaf spot and stem spot of H. cordata in Guanghan City was identified as D. houttuynia.

In order to investigate the occurrence of root knot nematode disease in rice-vegetable rotation fields of Guangxi, and clarify the pathogen species, a sampling survey on the occurrence of rice root-knot nematode disease was carried out in 171 rice-vegetable rotation fields in 27 townships of 14 cities in Guangxi. Nematodes were isolated from samples, and the species was identified by observing the morphological characteristics of second instar larvae and perineal pattern of females, and analyzing ribosomal ITS region and 28S rDNA D2D3 region sequences. The results showed that 64 fields of them were affected with root-knot nematodes, with a detection rate of 37.4% during the rice-growing season and 25.7% during the vegetable rotation. The species of root- knot nematode on rice in Guangxi was confirmed as Meloidogyne graminicola. It indicated that the disease caused by M. graminicola had occurred widely in rice-vegetable rotation fields in Guangxi, and more attention should be paid.

This study aimed to analyze the free amino acid components of wild soybean resources which were collected from various regions of Heilongjiang Province. 17 kinds of free amino acid content in 153 wild soybean resources were determined and analyzed systematically. The results indicated that the amplitude variation of methionine content was the highest among the 17 kinds of free amino acids with a variation coefficient of 0.469. The total free amino acid content was 2.069 mg/g, among which the arginine content was the highest (0.894 mg/g). Positive correlation was showed between any free amino acids and total free amino acids. There were significant positive correlations among most amino acids, while significant negative correlation could be found between aspartic acid and phenylalanine and between serine and arginine. The cumulative contribution rate of the first five principal components extracted from the principal component analysis reached 85.15%. The contribution rates of the first and second principal components were 26.47% and 20.55%, respectively. According to the first and second principal components, large discrepancies were discovered between the resources in the northern region and the central and southern regions, and small discrepancies were discovered between the resources in the eastern and western regions. In this study, the content variation and correlation among components of 17 kinds of free amino acids in wild soybean in cold region were analyzed, and the effects of different sources on the content and components of free amino acids were clarified, which provided important basic data for soybean breeding applications.

To provide reference materials for the development of bacteria and algae synergistic aquaculture technology, this paper outlines the basic information of algae and bacteria in aquaculture and water environment, describes the main algae and bacteria and their use in aquaculture, conducts different experiments to understand the influence of algae and bacteria on the culture water environment and the growth performance of culture organisms, and analyzes the role of bacteria and algae synergistic system on the culture water environment and the growth performance of culture organisms. Finally, we made an outlook on the optimization of new and efficient bacteria and algae synergistic control technology for aquaculture environment.

To reveal the impact of meteorological factors on the vertical gradient of water temperature, daily and hourly meteorological observation data from the Honghu National Meteorological Station in the summer of 2022 was used, as well as minute by minute water temperature observation data from different depths at the Honghu Aquatic Base, mathematical statistics and correlation analysis were used to analyze the vertical variation of water temperature in pond aquaculture on sunny days in summer. The results showed that: (1) on clear days in summer, the single peak daily variation characteristics of water temperature in each layer were obvious, with the minimum value appearing before sunrise, the highest value of surface water temperature appearing around 16:00. The deeper the water layer, the later the highest and lowest values appear. The changes in water temperature in the upper and lower layers had a certain lag. (2) Light had a significant impact on water temperature, and there was a significant positive correlation between the two factors. The correlation coefficient reached its maximum at a depth of 60 cm; the average illumination at different levels was negatively correlated with the vertical gradient of water temperature, while the illumination gradient at different levels was significantly positively correlated with the vertical gradient of water temperature. (3) There was a significant negative correlation between the vertical gradient of water temperature and wind speed. The higher the wind speed, the smaller the vertical gradient of water temperature. When the wind speed ranges from 3 to 4, and the vertical gradient of water temperature was small, it was advisable to temporarily postpone or reduce the use of oxygen generators in a timely manner. (4) There was a significant positive correlation between the vertical gradient of water temperature and water vapor pressure. The higher the water vapor pressure, the greater the vertical gradient of water temperature. In hot and humid weather, it was necessary to strengthen the patrol of the pond and timely start the aerator. The paper revealed the mechanism of the influence of meteorological factors on the vertical gradient of water temperature, and provided technical support for healthy aquaculture.

With the rapid development of aquaculture in China, the environmental problems caused by the discharge of aquaculture tailwater are becoming more and more serious. The treatment of aquaculture tailwater has emerged as a crucial research area in recent years. At present, the main methods of aquaculture tailwater treatments include physical, chemical, and biological treatments, which are often combined in practical production. Based on the research status at home and abroad, the physical, chemical and biological technologies of aquaculture tail water treatment were summarized and analyzed, and the development trend of aquaculture tail water treatment technology in China was prospected, aiming to provide some references and directions for aquaculture tail water treatment.