• Research softwareclose
• Other research productsclose
• 2019-2023close
• BE close
• Chinese close

Taking black soil as the research object, the difference in the three-dimensional fluorescence spectrum of soil dissolved organic carbon (DOC) after returning maize straw to the field at different soil depths (0~2, 3~10, 11~20, 21~30 and 31~40 cm) were analyzed. The change characteristics of humification degree of maize straw return to deep soil were discussed. The results showed that straw return could increase the content of soil DOC. The characteristics of three-dimensional fluorescence spectra showed that there were two kinds of fluorescence components of soil DOC. CK~T4 treatments were humus like components (Ex/Em=250~275/455 nm) and tryptophan like components (Ex/Em=225~237/340~350 nm), while T5 treatment was humus-like components (250~275/455 nm) and tyrosine like components (Ex/Em =225/304 nm), there were small authigenic components at a depth of 31~40 cm, and the humification coefficient was the highest. The fluorescence intensity of soil DOC component C1 increased with the deepening of straw returning depth, while the C2 component showed a fluctuating state, and the fluorescence intensity increased first and then decreased. Soil DOC was affected by both endogenous and exogenous sources (FI>1.4, 0.6

In order to obtain potato plants which could be resistant to multiple viruses ( viroid) simultaneous- ly，P25，HC-Pro，and Virp1 gene targeting PVX，PVY，and PSTVd proteins were cloned，respectively. Three types of amiRNAs targeting sequences encoding the silencing suppressor P25，HC-Pro and Virp1 were designed by using Ar- abidopsis thaliana miR159a as backbone. These three amiRNA sequences were connected by Overlapping PCR. The synthetic of P25，HC-Pro and Virp1 gene was inserted into the expression vector pCAMBIA1300-221 to form p1300-221-preamiR-P25-HCPro-Virp1，and the vector was verified by PCR and restriction enzyme digestion. Pre-a- miR-P25-HCPro-Virp1 was transformed into minituber of potato cultivar Favorita by Agrobacterium tumefaciens in- fection. 15 transformed plants were obtained through regenerating，pressure screening and differentiation. PCR re- sults showed that 10 of them were detected the same size fragment ( 729 bp) as the target gene. Further qRT-PCR t e s t i n g c o n f i r m e d t h a t a m i R - P 2 5 - H C P r o - V i r p 1 g e n e w a s e x p r e s s e d i n 1 0 t r a n s f o r m e d p l a n t s ，a n d t h e r e l a t i v e e x p r e s - sion was between 7. 68 - 21. 37. Inoculated the T0 transgenic plants with the mixture virus of PVX，PVY and PSTVd by friction into the leaves of the plants at the 6 - 8 leaf stage. The plant growth was observed after 20 days and the results showed that the control plants were severely susceptible，with symptoms such as short plants and mottled leaves，while the transformed plants did not show infection symptoms，and growth normally. There was no vi- rus detected by RT-PCR either. This indicated that the transfected amiR-P25-HCPro-Virp could be stably expressed in the transformed plants，and the transformed plants were resistant to PVX，PVY and PVSTd viruses ( viroid) . Transformed plants resistant to PVX，PVY and PVSTd were obtained，and the resistance was significant，which pro- vided new genetic resources for potato virus-resistant breeding.

he present invention concerns a method for assigning a pixel to one of a foreground pixel set and a background pixel set. In this method, if a first condition is met the pixel is assigned to the background pixel set , and if the first condition is not met and a second condition is met, the pixel is assigned to the foreground pixel set. The method comprises a step ( S100 ) of calculating a probability that the pixel belongs to a foreground-relevant object according to a semantic segmentation algorithm, the first condition is that this probability that the pixel belongs to a foreground relevant object does not exceed a first predetermined threshold, and the second condition is that a difference between this probability that the pixel belongs to a foreground relevant object and a baseline probability for the pixel equals or exceeds a second predetermined threshold.

Comment et pourquoi enseigne-t-on la théorie de l'évolution en Europe et plus particulièrement en Belgique francophone? Quels sont les enjeux et les moyens?

Wheat yellow dwarf disease is caused by barley yellow dwarf virus (BYDV), which is transmitted by wheat aphid and causing huge loss in agriculture. Nowadays, induced resistance has aroused great discussion as a new measure to control plant pathogens and herbivores. Protein elicitor Hrip1 induced defense response in various plants, leading to broad spectrum resistance. In this study, we evaluated the control efficiency of Hrip1 against BYDV. Wheat seeds and seedlings were soaked and sprayed with 30 μg/mL Hrip1, respectively, and then inoculated with BYDV. The control efficiency of Hrip1 against BYDV was over 50% at 14th dayafter BYDV inoculation and over 30% at 21th dayafter BYDV inoculation. Q-RT- PCR test showed that quantity of mRNA for BYDV coat protein was less in Hrip1 treated wheat seedlings than that of control. EPG test showed that Schizaphis graminum performed longer time to find probe site on leaf surface and feeding site in phloem on Hrip1 treated wheat seedings. These results suggested that Hrip1 is efficient in inhibiting BYDV proliferation, and affecting feeding behavior of S. graminum, futher more reducing virus transmission ability of S. graminum. Additionally, Hrip1 weakened the symptom of dwarf and yellow in wheat seedlings caused by BYDV. In conclusion, Hrip1 could be a biological agent to integrately control BYDV. National Key R&D Program of China; Chinese Academy of Agricultural Sciences

Renommée depuis la plus haute antiquité pour son ancienneté et son excellence, la médecine égyptienne a-t-elle pu influencer la médecine occidentale et, si tel est le cas, en quoi et de quelle manière ? Que s’est-il passé lorsque la médecine grecque héritée d'Hippocrate a été importée en Égypte à la suite de la conquête du pays par Alexandre le Grand, en 332 avant notre ère ? Après avoir comparé les écrits médicaux égyptiens et grecs et les pratiques médicales attestées dans le Pays du Nil et dans le monde hellénique, on examinera, à côté des sources littéraires qui font de l' « école médicale d'Alexandrie » un modèle qui restera pour longtemps inégalé, les papyrus médicaux grecs (des IVe/IIIe siècles avant notre ère au VIIe siècle de notre ère), retrouvés en nombre sans cesse croissant dans les sables égyptiens, ainsi que d'autres sources archéologiques, en vue de répondre à ces questions.

【方法】供试黑土长期定位试验位于吉林省公主岭市，始于1990年。2018年选择其中不施肥(CK)，施氮钾肥 (NK)，施氮磷钾肥(NPK)和氮磷钾+有机肥(NPK+M) 4个处理小区，采集0-20、20-40和40-60 cm土层的 土壤样品，分析了土壤理化性质，采用恒温平衡法测定了土壤磷的吸附-解吸特征，并由此计算得到磷最大吸附 量(Q m)、吸附亲和力常数(K Q)、最大缓冲容量(MBC)、磷吸附饱和度(DPS)、最大解吸量(D m)和解吸率(D r)。 【结果】随着平衡溶液中磷浓度的增加，磷的吸附量与解吸量均呈先快速增加后逐渐趋于平衡的过程。与不施 磷处理(CK和NK)土壤相比，施磷处理(NPK、NPK+M)减少了磷的吸附量，增加了磷的解吸量。与不施磷处 理相比，施磷处理在0-60 cm剖面上的Q m 和MBC值分别降低了4.94%～63.46%和15.90%～75.18%，D r 值增 加了8.52%～474.0%，以NPK+M处理变化量最大。施磷处理比不施磷处理在0-60 cm土壤剖面上全磷和有机 质含量分别增加了34.40%～145.5%和12.77%～50.07%，游离态铁铝氧化物(Fe d +Al d)含量降低了 5.14%～11.35%。冗余分析表明，不施磷处理土壤的有机质、Fe d +Al d 和全磷，以及施磷处理中的Fe d +Al d 、络合 态铁铝氧化物(Fe p +Al p)、pH和有机质是影响磷吸附解吸特征参数的主要土壤因子，分别解释了不施磷和施磷处 理全部变异的77.59%和90.62%。土壤有效磷(Olsen-P)与磷吸附饱和度(DPS)相关关系表明，所研究的黑土