In vertebrates, the development of the central nervous system depends on the correct patterning of the neural tube along its anterior-posterior and dorsal-ventral axes in the early embryo as well as the underlying regulation of the cell differentiation. During the neural tube formation, the arrangement of the precursor cells depends on the regulation of different morphogen concentration gradients. The most important morphogens during the neural tube development are the bone morphogenetic protein (BMP) secreted from the roof plate and the Sonic hedgehog (Shh) secreted from the floor plate, which would form an antiparallel concentration gradient in the neural tube. These morphogen concentration gradients could further provide the positional information to the precursor cells and gradually determine their differentiation fate. In this paper, we summarized the process of neural tube development in different model organisms, focusing on the important role of two morphogens of BMP and Shh in the formation of dorsal-ventral pattern of the neural tube. Besides, a better understanding of the developmental mechanism of the nervous system in vivo would also provide some insights on the construction of neural tube organoids in vitro. Therefore, we also pointed out the latest progress of neural tube organoids and discussed the future perspective of this field.

The application of ovum pick-up (OPU) and in vitro embryo production (IVP) can significantly improve the reproductive efficiency of cows, which is of great significance for the propagation of superior breeds of dairy cows and beef cattle. In recent years, OPU/IVP technology has spread rapidly around the world and gradually replaced in vivo derived (IVD) technology to be the most wildly used method of embryo transfer. However, the technical system is still in its infancy in China due to the low efficiency and high technical difficulty in operation, which is the main restriction factor for genetic improvement of dairy cows and beef cattle in China. In this paper, we reviewed the current situation of OPU/IVP, the technical progress as well as the prospect of the application of OPU/IVP in the propagation of superior breeds of dairy cows and beef cattle, aiming to provide references for the complement of China’s OPU/IVP technical system and the improvement of efficiency of bovine reproduction, thereby promoting the development of bovine breeding in China.

Taking satsuma mandarin (Citrus unshiu Marc.) grown in mountainous areas as the research object, and custom fertilization of farmers (only applying chemical fertilizer, the input amounts of N, P₂O₅, K₂O were 211.5, 180.0, 220.5 kg/hm², respectively) as the control (CF), different combinations of fertilization with organic matter and chemical fertilizer decrement (DF1: the input amounts of N, P₂O₅, K₂O were 153.0, 63.0, 157.5 kg/hm², respectively; DF2: the input amounts of N, P₂O₅, K₂O were 180.0, 108.0, 211.5 kg/hm², respectively) were set to study the effects of drip fertigation on citrus yield, quality, nutrient absorption and soil fertility. The results showed that citrus yields of drip fertigation treatments with DF1 and DF2 increased by 17.5% and 16.4%, respectively, as compared with the control. The drip fertigation treatments with DF1 and DF2 could also increase fruit quality. The total soluble solid content increased by 11.4% and 10.5%, and vitamin C content increased by 26.7% and 13.6%, and the total acid content decreased by 16.2% and 21.6%, respectively, as compared with the control. In addition, drip fertigation treatments could significantly increase the absorption of calcium (Ca), magnesium (Mg) and boron (B) in leaves and fruits, which were higher than those of the control. Drip fertigation treatments also had a great impact on soil pH and soil fertility. The soil pH value of DF1 and DF2 treatments was higher than that of the control, and the organic matter content increased by 27.1% and 20.0%, respectively, and the hydrolysable nitrogen (N) content increased by 88.3% and 105.2%, respectively. The soil exchangeable Ca, exchangeable Mg and available B contents were also significantly higher than those of the control. It can be seen that while saving chemical fertilizer, drip fertigation can improve soil fertility, promote the nutrient absorption and utilization of leaves and fruits, and then increase citrus yield and improve fruit quality. Therefore, drip fertigation is an important measure to reduce chemical fertilizer application, improve quality and efficiency in citrus orchards.

In this study, two acylated flavonol tetraglycosides {quercetin-3-O-[(E)-p-coumaroyl-(1→2)][α-L-arabinopyranosyl-(1→3)]-[β-D-glucopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→6)]-β-D-glucopyranoside，F₁；kaempferol-3-O-[(E)-p-coumaroyl-(1→2)]-[α-L-arabinopyranosyl-(1→3)]-[β-D-glucopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→6)]-β-D-glucopyranoside，F₂} were isolated and purified from Camellia sinensis, and the distribution characteristics of F₁ and F₂ in different tissues, leaf positions, and tea cultivars were systematically studied through the independent established high performance liquid chromatography (HPLC) method. The effect of light on the contents of F₁ and F₂, and the dynamic changes in the processing stages of oolong tea were also studied. The results showed that F₁ was mainly distributed in tea leaves and stems, and F₂ was only present in leaves; neither F₁ nor F₂ was detected in the roots. With the increase of leaf maturity, the contents of F₁ and F₂ firstly increased and then decreased. Among the 42 tea cultivars, the contents of F₁ and F₂ ranged from 0-2.31 mg/g and 0-1.56 mg/g, respectively. F₁ had the highest content in ‘Huangjinju’ and was not detected in ‘Benshan’ and ‘Lüyafoshou’ tea cultivars. F₂ had the highest content in ‘Huangjinju’ and was not detected in ‘Lüyafoshou’, ‘Jinmian Qilan’, ‘Zhonghuang No. 2’ and ‘Benshan’. Shading experiments were carried out on three tea cultivars, and it was found that the content of F₁ in the shading treatment group was significantly reduced, indicating that the light plays a significant role in the formation of F₁. The fresh leaves of ‘Fujian Shuixian’ were selected for the processing of oolong tea. The contents of F₁ and F₂ showed downward trends during the whole processing stages, and the largest decline was observed in the process of fixation, while the smallest was in the process of rotation, which shows that different processing operations have different degrees of influences on the contents of two substances.

Terpenoids play important biological and ecological roles in plant defense against the pests’ stress, and geranyllinalool synthase (GES) is a key enzyme in the biosynthetic pathway of terpenoids. In order to understand the function of GES in Brassica oleracea, wecloned the BoGES gene by polymerase chain reaction and analyzed its expression levels under different biological stresses, after that we studied the recombinant protein by prokaryotic expression and analyzed its biochemical functions. The results showed that the amino acid sequence of BoGESprotein was highly conserved in Brassicaceae, indicating its conserved function in these plants. The expression of BoGES gene could be significantly induced by diamondback moth (DBM) damage, Pst DC3000 infection, and salicylic acid and methyl jasmonate treatments, suggesting its functions in response to the biological stresses. BoGES protein could catalyze the formation of geranyllinalool from the substrate geranylgeranyl diphosphate (GGPP). Moreover, we measured the choice response of the parasitoid wasps to different concentrations of geranyllinalool via the Y-tube olfactometer, and found that this chemical could attract the parasitoid wasps. In conclusion, this study systemically analyzed the function of BoGES gene in B. oleracea, which could provide the scientific basis for further study of the biological and ecological functions of terpene synthase and terpenoids in Brassicaceae plants.

Functions and mechanisms of cyclic nucleotide-gated ion channel (CNGC) in plant immunity against necrotrophic pathogens remain largely unknown. In this study, we explored the functions of AtCNGC3 in immunity against Sclerotinia sclerotiorum, a typical necrotrophic pathogen, through identifying subcellular localization of its expression product, defining its expression patterns and genetically analyzing its function in immunity. The results showed that AtCNGC3 protein was localized in plasma membrane. AtCNGC3 was highly expressed in all analyzed tissues of Arabidopsis thaliana without showing any tissue specificity. Sclerotinia sclerotiorum inoculation strongly and constantly induced the expression of AtCNGC3 gene. The Atcngc3 mutant plants were more susceptible to S. sclerotiorum, while AtCNGC3 overexpression (AtCNGC3-OE) plants exhibited enhanced resistance to S. sclerotiorum, indicating that AtCNGC3 positively regulates the resistance to S. sclerotiorum. Seedlings soaking with Arabidopsis thaliana plant elicitor peptide 1 (AtPep1) could rapidly induce AtCNGC3 gene expression. AtPep1-elicited reactive oxygen species (ROS) burst was weakened in the Atcngc3 mutant seedlings while enhanced in the AtCNGC3-OE plants, demonstrating that AtCNGC3 positively regulates AtPep1-induced ROS burst. Collectively, our results reveal that AtCNGC3 positively regulates immunity against the necrotrophic fungal pathogen S. sclerotiorum in Arabidopsis, thereby providing some insights into the functions of CNGC in plant immunity.

Non-point source nitrogen (N) pollution is one of the major environmental threats of water quality degradation in agricultural watersheds. Based on the monitoring data of N output at riverine outlet section and the calculation of net anthropogenic nitrogen input (NANI) in the Changle River watershed of Shengzhou City, Zhejiang Province from 2003 to 2016, the response relationships of riverine water quality to NANI and meteorological factors driving non-point source pollution were explored, and a response model was established to evaluate riverine N pollution sources in this study. The results showed that, during the study period, the average NANI was 95.77 kg/(hm²·a), among which chemical fertilizer N, net human food and animal feed N, atmospheric N deposition, biological N fixation and seed N contributed 53.90, 25.62, 11.94, 4.18 and 0.13 kg/(hm²·a), respectively. The average riverine N export was 2 178.78 t/a, which was positively correlated with NANI and precipitation, and negatively correlated with evaporation and wind speed in the studied watershed. Accordingly, the simulated results of the response model [R²=0.801 0, Nash-Sutcliffe efficiency coefficient (NSE)=0.799 1] showed that the historical remained N in the watershed, the NANI of the current year and the riverine background N accounted for 66.8%, 30.8% and 2.4% of the riverine N export, respectively. These results indicated that the historical remained N in the watershed was the largest contributor to riverine N pollution with a long-term impact on riverine water quality, which implied the existence of lag effect of riverine water quality in response to the measures of N emission reduction in the watershed. Therefore, the implementation of long-term N control measures should be an important strategy to prevent and control riverine N pollution in agricultural watershed.

To improve the degradation efficiency of cellulose distributed in livestock, poultry wastes and garden wastes, a high-efficiency cellulose-degrading fungus which was from bamboo shavings, dead branches, and rotted leaves, and sheep dung was screened with Congo red staining, filter paper disintegration test and the endoglucanase [carboxyl methyl cellulose (CMC)] activity was tested. The physiological and molecular identification of the strain was carried out. The results showed that a high-efficiency cellulose-degrading fungus was screened in this study, which was identified as Trichoderma longibrachiatum by morphological observation and fungus species identification, and named as T. longibrachiatum ZJ-10. Single factor test showed that the conditions for achieving the maximum enzyme production activity showed as follows: 3% inoculation, initial pH 6.5, rotation speed of 160 r/min, 40 ℃, and cultured for 5 d. According to Plackett-Burman experimental design, Box-Benhnken steepest climbing path method and response surface methodology, the optimal enzyme production medium formula was 5 g/L NaCl, 7 g/L peptone, and 12 g/L CMC-Na. Under the optimal conditions, the CMC enzyme activity of strain ZJ-10 could reach 80.32 U/mL, which was 26.45% higher than that of the former optimization. In conclusion, strain of T. longibrachiatum ZJ-10 with strong CMC enzyme activity was screened in this study, which provides a good strain resource for the utilization of livestock, poultry and garden waste resources.

In order to explore the migration and enrichment law of uranium (U) and its related elements in farmland soils (aeolian sandy soils) and plants in Qianjiadian U mining area of Inner Mongolia, the roots, stems, leaves and rhizosphere soil samples of zoysiagrass, sorghum, peanut, corn, willow and poplar were collected systematically. The contents of 13 kinds of heavy metal elements such as uranium (U), arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), antimony (Sb), thorium (Th) and zinc (Zn) were analyzed, as well as their bioconcentration factors and translocation factors among the soils and plants. The results showed that: 1) The content of heavy metal elements in the aeolian sandy soil of Qianjiadian U mining area was low, and the concentration coefficient was mostly lower than one. Uranium was significantly positive correlation with other elements. 2) The contents of heavy metal elements in the zoysiagrass and its rhizosphere soil were higher than those of other plants. 3) The plants had selective absorption of heavy metal elements, among which poplar had the strongest enrichment effect on Cd, while zoysiagrass, peanut and willow could enrich Cu, Mo and Zn, respectively. 4) The absorption of heavy metal elements by various organs was generally in the order of leaf＞root＞stem. On the whole, the content of heavy metal elements in the aeolian sandy soil is low, and the plants have strong selective absorption capacities of Cd and Zn in soil, and strong tolerance to heavy metal elements. Zoysiagrass, sorghum and peanut can be used as candidate plants for ecological restoration after mining.

By selecting a typical blue clayey paddy soil with planting single-season rice in the southeast coast, we studied the effects of urea fertilizer containing N-(n-butyl) thiophosphoric triamide (NBPT, urease inhibitor) and 3, 4-dimethylpyrazole phosphate (DMPP, nitrification inhibitors) biochemical inhibitors on the nitrogen transformation in the surface water and soil and rice growth under the different fertilization times and levels. The results showed that: compared with the conventional urea fertilizer treatment, when the urea added with NBPT and DMPP combined biochemical inhibitors was applied twice as 50% base fertilizer and 50% topdressing, the concentrations of ammonium, nitrate and nitrite in field surface water decreased by 7.0% and 13.2%, 46.5% and 50.5%, 75.4% and 58.2% at the regreening stage and early tillering stage of rice, respectively; the ammonium concentration in soil decreased by 21.8% at the regreening stage and increased by 27.5% and 9.3% at the later tillering stage and jointing stage of rice; besides, the plant height, tiller number and chlorophyll content of rice were increased by 4.8% and 4.1%, 4.9% and 11.8%, 17.8% and 15.9% at the tillering stage and jointing stage, respectively. Furthermore, the yield and biomass of rice increased by 6.8% and 12.5%, 9.2% and 12.6%, respectively, at the mature stage, when the urea added with NBPT and DMPP combined biochemical inhibitors was applied once as base fertilizer or twice as 50% base fertilizer and 50% topdressing. In conclusion, the combined application of NBPT and DMPP biochemical inhibitors can effectively inhibit the rapid increase of ammonium and nitrate nitrogen in soil and field surface water, delay the transformation rate of nitrogen form, and maintain the relatively low nitrate nitrogen concentration in the surface water and soil in the rice fields, which can reduce the risk of nitrogen loss in paddy fields, promote rice growth and increase rice yield.

In order to investigate the molecular epidemiology and genetic variation of porcine circovirus type 2 (PCV2) in Zhejiang Province, a total of 1 725 clinical samples suspected of PCV2 infection were collected from different regions of Zhejiang Province between 2016 and 2020. All these samples were subjected to pathogenic detection by polymerase chain reaction (PCR). The whole genomes of some positive samples were amplified, cloned and sequenced, and compared with sequences of 16 reference strains in the GenBank for genetic evolution analysis. The results showed that 359 samples were tested positive, with an average positive rate of 20.8%, and the positive rates from 2016 to 2020 were 38.1%, 23.2%, 24.1%, 12.5%, and 10.7%, respectively. The whole genomes of 36 isolates were sequenced. Multiple sequence alignments showed that the nucleotide sequence homologies among 36 PCV2 strains were 94.0%-99.9%, while the homologies were up to 94.7%-98.5% compared with the domestic vaccine strains, and 92.9%-99.8% compared with the reference strains. The phylogenetic analysis showed that these 36 isolates belong to three genotypes, including 11 strains of PCV2a genotype, eight strains of PCV2b genotype and 17 strains of PCV2d genotype. Among these, PCV2d was the predominant genotype. The length of PCV2 ORF2 gene was 705 bp in 16 isolates and 702 bp in 20 isolates. The nucleotide sequence homologies of ORF2 gene among these 36 isolates were 88.7%-100.0%, while the homologies were 90.2%-99.6% compared with the domestic vaccine strains, and 85.0%-100.0% compared with the reference strains. The amino acid sequence analysis of Cap protein indicated a large number of point mutations in addition to the only highly conserved glycosylation site. Moreover, different genotypes had characteristic mutation sites, and the specific mutation sites of dominant genotype PCV2d were mainly concentrated in I⁵³, N⁶⁸, L⁸⁹, T¹²¹, R¹⁶⁸, and I²¹⁵. This study provides a reference for the immune prevention of PCV2 in Zhejiang Province and accumulates effective materials for the development of new vaccines.

In order to explore the relationships between morphometric traits and body mass (BM) of sea cucumber (Apostichopus japonicus), correlation analysis and path analysis were used to obtain the main morphometric traits affecting body mass. Three morphometric traits including body length (BL), body width (BW) and body mass of 366 individuals of F₅ generation breeding population at one year old were measured, and one compound index that combined body length and body width to produce the square root of the length-width (SLW) index was calculated. The results showed that the correlation coefficients between morphometric traits and body mass were highly significant. The stepwise regression analysis showed that morphometric traits (SLW and body width) and body mass were significantly positive correlations (P＜0.001). Based on path coefficients, the multiple linear regression mode equation on the effects of body mass was established as BM=－16.14+6.70SLW+4.31BW. The morphometric traits that directly affected body mass were SLW＞BW, and SLW was the main morphometric trait that significantly affected body mass and its path coefficient was 0.62. Body width had an indirect effect on the body mass via SLW. The fitting relationships between morphometric traits and body mass were expressed as following BM=0.39SLW^2.66 (R²=0.86, P＜0.001), showing negativeallometry tendency. The results provide valuable information and theoretical guidance for A. japonicus breeding programs. Body width should be selected directly and body length simultaneously, when body mass is the breeding target.

In view of the low efficiency of picking high-level apples from fruit trees by fruit farmers, a pipeline transportation device for assisting manual picking was designed. In order to optimize the transportation parameters of the device, a test bench for impact force was established. Taking 'Fuji' apples as the research object, the impact force and mechanical damage of 'Fuji' apples with a fruit diameter of 80-90 mm from a height of 3 m along the pipeline to the fruit box were analyzed. Taking the type of pipeline lining, the lining thickness, and the crash pad thickness as the test factors, and the impact force and damage volume of apples when they fell into the fruit box as the indexes, the response surface test was carried out on the basis of the single factor test. The results of single factor test showed that the pearl cotton material had a relatively good protective effect on apples. The impact force and damage volume gradually decreased with the increase of the lining thickness, and gradually decreased with the increase of the crash pad thickness. The results of the response surface test showed that the optimal combination of transportation parameters was as follows: the lining type was pearl cotton, and the lining thickness was 10 mm, and the crash pad thickness was 8 mm. At the optimal combination conditions, the impact force when the apple fell into the fruit box was 4.99-5.47 N, and the damage volume was 275.02-300.52 mm³. The results of verification test showed that the errors of the impact force and the damage volume of apple were both less than 5%, indicating that the optimization results of pipeline transportation parameters are reliable.