Sponsor(s): Chinese Academy of Agricultural Sciences；Chinese Association of Agricultural Science Societies
24 issues per year
Current Issue: Issue 14, 2018
Scientia Agricultura Sinica, the 1st in Comprehensive Agricultural Science, is supervised by Ministry of Agriculture of PRC, and sponsored by Chinese Academy of Agricultural Sciences; Chinese Association of Agricultural Science Societies. Scientia Agricultura Sinica, launched in 1960, is a leading peer-reviewed and mufti-disciplinary journal and published semi-monthly in Chinese with English title, abstract, figures, tables and references. It aims to publish those papers that are influential and will significantly advance scientific understanding in agriculture fields worldwide. The scope covers Crop Genetics, Breeding, Germplasm Resources; Physiology, Biochemistry, Cultivation, Tillage Plant Protection; Soil & Fertilization, Agro-Ecology & Environment, Bio-energy; Animal Science, Veterinary Science, Agricultural Information Science; Food Science; Agricultural Economics and Management; Agricultural Sustainability. The journal is included in JST, CA and CSCD.
Editor-in-Chief Wan Jianmin Associate Editor-in-Chief Zou Ruicang Tang HuaJun Wu Kongming Guo YuYuan Geng Xu Sun Tan Executive Editor Lu Wenru
Scientia Agricultura Sinica,2018,Vol 51,No. 14
[Objective] The main cabbage varieties in production were collected and DNA fingerprinting of cabbage varieties were constructed with SNP markers to provide reference for variety distinctness and authenticity identification. [Method] SNP loci were obtained by aligning resequencing data of 50 cabbage inbred lines to the reference genome of cabbage (02-12). The SNP loci were screened with two criteria: (i) high polymorphism information content (PIC), (ii) evenly distribution on each chromosome. And then KASP primers were designed based on these loci. The KASP platform was used to genotype the fifty-nine cabbage varieties. According to the result of genotyping, core primers were selected with high PIC value, no loci missing and even distribution on each chromosome. These core primers were used to establish SNP fingerprinting of fifty-nine cabbage varieties. The fifteen varieties randomly selected from the fifty-nine main varieties and five new unreleased combinations were mixed together to construct an artificial population. The artificially mixed population was used to validate the core primers in the variety distinctness and authenticity identification. [Result] Two million five hundred and forty thousand SNP loci were obtained by aligning the resequencing data of fifty cabbage inbred lines to the reference genome of cabbage. Five hundred SNP markers were selected with high PIC value, low missing rates and even distribution on each chromosome, with 55.6 loci per chromosome. Four hundred and forty-two of them were successfully transformed into KASP markers, occupying 88.4% of all the 500 SNP markers. The genotyping results showed that twenty-five pairs of KASP primers were unsuccessfully genotyped in more than five materials and were removed from further analysis. The PIC values among the 417 primers ranged from 0.12 to 0.38. The average PIC value was 0.36, showing moderate polymorphism. The number of varieties with heterozygous marker ratio greater than 30% was 57, occupying 88.4% of all the main varieties. The heterozygous marker ratio of ‘Yushengzaoshuniuxin’ was the highest, which reached 67.8%. Finally, fifty core markers were selected to construct DNA fingerprinting of 59 main varieties. The PIC values of 50 core makers ranged from 0.35 to 0.38, and the average PIC was 0.36. The result of cluster analysis of core SNP markers indicated that the genetic similarity coefficient of 59 varieties varied from 0.43 to 0.98. The core SNP markers were validated by artificially mixed population and the results showed that the SNP fingerprinting constructed with core markers could be used to identify the variety distinctness and authenticity effectively. [Conclusion] Two million five hundred and forty thousand SNP loci were obtained by aligning resequencing data of cabbage inbred lines. Fifty pairs of core makers were selected and used to establish DNA fingerprint database of 59 cabbage varieties, and the core SNP markers were validated by artificially mixed population.
Effect of Different Concentration of Apple Polyphenols on the Physico-chemical Properties of Chitosan Membrane Fluids
Scientia Agricultura Sinica,2018,Vol 51,No. 14
[Objective] The composite membrane fluids based on chitosan (5%, w/ V) and varying concentration of apple polyphenols were developed in this work, and the composite membrane fluids with different polyphenol concentrations were fully investigated including their antioxidant activity, rheological properties and thermal stability. This result could provide the theoretical basis for food preservation. [Method] The composite membrane fluids were prepared by adding different amounts of apple polyphenols (0.5%, 1.0%, and 1.5%, respectively). Besides, the effect of different concentrations of apple polyphenols on the antioxidant activity of the composite membrane fluids was measured. A controlled-strain rheometer was used to investigate static rheological properties of the composite membrane fluids, including the relationship between G′ and G″. The potential interactions between chitosan and apple polyphenols and the crystal structure of the composite membrane were characterized by Fourier transform infrared spectrum (FTIR) and X-ray diffraction, respectively. In addition, thermogravimetric (TG) and derivative thermogravimetric (DTG) analyses were conducted by using the thermal analysis equipment to characterize the thermal stability of the lyophilized composite membrane samples. [Result] The addition of apple polyphenols could significantly improve the antioxidant activity of the chitosan membrane fluids ( P < 0.01). The increase of apple polyphenol concentration could lead to the increased antioxidant ability of the composite membrane fluids. When the concentration of apple polyphenols was 0.5%, the DPPH scavenging rate, inhibition capacity of lipid oxidation and OH radical scavenging rate were determined to be 41.33%, 56.32%, and 35.44%, respectively. As the concentration of apple polyphenols was increased to 1.5%, the antioxidant ability of the composite membrane fluids was increased to 94.3%, 95.9%, and 98.4%, respectively, significantly higher than that of 0.5% polyphenol-incorporated composite membrane fluids ( P < 0.01). Compared with the BHT (1.5%), the antioxidation properties of the composite membrane fluids with 1.5% apple polyphenols were higher ( P < 0.01). Moreover, the rheological analysis suggested that the composite membrane fluids were non-Newton pseudoplastic liquids (n < 1, R2 > 0.99). With the increase of shear rate, the viscosity of the composite membrane fluids displayed an initially decreasing but then a relatively stable trend (approximately 5 Pa·s). Meanwhile, the incorporation of apple polyphenols enhanced the viscoelastic property of the composite membrane fluids. The dynamic rheology of the composite membrane fluid transformed from G′ < G″ into G′ > G″. The results of FTIR and X-ray showed that the intermolecular interactions of apple polyphenols (-OH) and chitosan (-OH, -NH 2) were formed, resulting in the slight change of absorption peak of the composite membrane at 3 400 cm −1, 1 545 cm −1 and 1 245 cm −1 and resulting in the reduced crystallinity of chitosan. According to the result of thermal analysis, the thermal stability of the composite membrane fluids increased, probably due to the hydrogen bonds formed via the linkages between apple polyphenols and chitosan. [Conclusion] The composite membrane fluids prepared by adding apple polyphenols into the chitosan had higher antioxidant capacity, viscosity and thermal stability, thus could be used as a potential edible coating material for food preservation.
Targeted Mutagenesis of NbbZIP28 and Its Stress Response to Virus Infection in Nicotiana benthamiana
Scientia Agricultura Sinica,2018,Vol 51,No. 14
[Objective] bZIP transcriptional factors are involved in plant development, hormonal signal, disease resistance, and other abiotic stress responses. The previous study showed that the Tobacco mosaic virus (TMV) or Cucumber mosaic virus (CMV) infection up-regulated the endoplasmic reticulum stress (ERs) gene NbbZIP28, and knock-down of NbbZIP28 increased the susceptibility to virus than wide type (WT). The mechanism of its stress response to virus infection still needs to be verified. [Method] NbbZIP28 mutant plants were obtained by CRISPR/Cas9 gene editing technique and tobacco genetic transfection. The susceptibility of mutants to virus infection and the ER stress-related UPR gene expression in mutants were compared with those in wide type by qRT-PCR. Then, the fusion protein of NbbZIP28-GFP was expressed transiently in leaves of Nicotiana benthamiana in advance of inoculation with TMV 24 h or CMV 48 h, and its hydrolyzation induced by viral infection was checked by Western blot. The cis-acting elements involved in defense and stress response in promoter region of NbbZIP28 were analyzed by Plant CARE. [Result] The DNA deletion of 10 bp was found in the target sites of NbbZIP28, leading to translation error and protein function variation. Under normal conditions, the mutant plants showed no different phenotype from WT. Upon inoculation TMV-GFP, the mutant plants showed more virus-infected spots and faster expansion than WT. Upon inoculation with CMV, the UPR-related genes ( BiP, PDI, CAM, and NF-YC2) showed lower expression in mutants than that in WT plants 12–48 hours post inoculation. In addition, the mutant plants showed more virus accumulation than WT at 5–7 days, the mosaic and shrinkage symptoms were more significant. The protein sequence alignment analysis showed that NbbZIP28 had the same hydrolytic site of S1P and S2P as AbZIP28. The Western blot detection found that TMV or CMV infection significantly promoted the full length of NbbZIP28-GFP to be cleaved at the sites of S1P and S2P than inoculation with water. There were five cis-acting elements involved in heat stress responsiveness (HSE), three cis-acting elements involved in low-temperature responsiveness (LTR) and one cis-acting element involved in defense and stress responsiveness (TC-rich repeats). [Conclusion] Virus infection activated NbbZIP28 and up-regulated its related UPR genes. NbbZIP28 knockout increased the susceptibility to virus than WT, and the virus-induced UPR gene expression was suppressed in mutant plants. NbbZIP28 was the regulating factor of UPR under virus infection stress and played a role in suppressing viral infection at early stage through up-regulating UPR signal and increasing the plants basic defense responses.
Relationships of N, P and K Requirement to Wheat Grain Yield of Farmers in Major Wheat Production Regions of China
Scientia Agricultura Sinica,2018,Vol 51,No. 14
【Objective】It is of great significance to clarify relationships of NPK requirement to farmers’ wheat grain yield for reasonable fertilization and decreasing fertilizer application rates. 【Method】A two years long on-farm survey combined with sample collection and analysis related to wheat production were carried out in the Spring Wheat (SW), Dryland Wheat (DW), Wheat-Maize (WM), Rice-Wheat regions (RW) of China, to study the relationships of NPK requirement to wheat grain yield of farmers. 【Result】The mean grain yield of wheat was observed to be 6.4 t • hm −2, and the differences were significant among the yield averages of different regions, with the grain yield average of 6.0 t • hm −2, 4.0 t • hm −2, 7.7 t • hm −2, 5.5 t • hm −2 in SW, DW, WM and RW region, respectively. The high yield regions usually had higher above-ground biomass and spike numbers, and harvest indexes increased with grain yields. The average N requirement was 28.1 kg • Mg −1, with the average of 28.6 kg • Mg −1, 28.3 kg • Mg −1, 29.3 kg • Mg −1 and 25.0 kg • Mg −1 in SW, DW, WM and RW region, respectively, and the N requirement average decreased significantly by 16.9% and 16.4% in DW and WM, tending to decrease but being not significant in SW and RW regions, when the yield was increased from the very low to the very high levels. The average P requirement was 4.0 kg • Mg −1, with the average of 4.5 kg • Mg −1, 3.2 kg • Mg −1, 4.1 kg • Mg −1 and 4.1 kg • Mg −1 in SW, DW, WM and RW region, respectively. P requirement average decreased significantly by 11.4% and 17.8% in WM and RW, decreased by 8.6%but not significant in DW region, when the yield was increased from the very low to the very high levels, and even though the lowest P requirement of 3.7 kg • Mg −1 occurred at the very low wheat yield level, it was still significantly decreased by 21.4%, when the yield was increased from the lower to the very high level. The average K requirement was 21.5 kg • Mg −1, with the average of 26.5 kg • Mg −1, 17.1 kg • Mg −1, 23.3 kg • Mg −1 and 18.8 kg • Mg −1 respectively and significantly different in the four regions, and the K requirement average significantly decreased by 4.0%, 4.4%, 12.7% and 19.9% in SW, DW, WM and RW region, respectively, when the yield was increased from the very low to the very high levels, although the difference was only significant in the RW region. 【Conclusion】Wheat grain yield of farmers were significantly different among the main wheat production regions in China, relationships of NPK requirements to grain yields were also different with regions, and generally they tended to decrease with the grain yield increase. Therefore, fertilizer application recommendation should determine the reasonable nutrient requirement based on the yield levels, the crop nutrient requirement characteristics and the land soil nutrient supply capacities of farmers, in order to avoid over or insufficient fertilizer application in different regions of China.