Abstract:In order to explore the characteristics of NnPIN family members in lotus (Nelumbo nucifera G.) and their role in abiotic stress response, this study used bioinformatics methods to identify the whole genome of lotus NnPIN family, and used qRT-PCR technology to analyze its response to low temperature ( 4℃), water flooding and exogenous application of 3 mmol/L abscisic acid (ABA). The results showed that, (1) A total of 12 NnPIN genes with transmembrane domains were identified in the lotus genome, named NnPIN1~12 respectively, and were distributed on 6 chromosomes, and mainly located in the plasma membrane and endoplasmic reticulum. (2) Phylogenetic analysis showed that NnPIN genes can be divided into two types: classic and non-classical based on the length of the central hydrophilic ring, and the same type has a similar structure; the classic type has complete motifs 1 to 12, but the non-classic type The central hydrophilic ring part (motif 6,8,9,12) is missing. (3) Cis-acting element analysis found that the NnPIN gene has a large number of light-responsive, abiotic stress and hormone-responsive elements in the promoter region, and specifically has anaerobic, abscisic acid (ABA), low temperature and other response elements. (4) The expression pattern of NnPIN genes showed that the NnPIN family genes (except NnPIN8) all respond positively to exogenous ABA and low temperature stress, while NnPIN6 and NnPIN7 positively respond to flooding stress, and NnPIN1, NnPIN2, NnPIN3, NnPIN4, NnPIN5, NnPIN8, NnPIN9 and NnPIN12 respond negatively to flooding stress. The study speculated that NnPIN family genes are specifically involved in lotus abiotic stress.

Abstract:Abstract: Plants are often subjected to many abiotic stresses. Temperature and high salt are one of the important abiotic factors affecting plant growth and development. Therefore, it is particularly important to study the molecular mechanism of plant response to stress. In this study, 7 members of KcHTR gene family were screened and cloned from the high-temperature transcriptome data of desert plant Karelinia caspica. By constructing prokaryotic expression vectors and inducing expression, it was clear that the length of their cDNA was 708 ~ 789 bp, the molecular weight of the expressed protein was 27 ~ 29 kD, and the encoding gene was consistent with the size of the protein. Through experimental exploration, it was found that under the optimal growth temperature of 37℃, the optimal expression system of this family protein was OD600 0.8, the induction concentration of IPTG was 0.5 mmol/L, and the induction time was 8 ~ 10 h. Through simulated high temperature, low temperature and salt stress treatment of recombinant E.coli, the results showed that KcHTRs could enhance the host tolerance to high temperature, low temperature and high salt to a certain extent, which was consistent with the results of abiotic stress expression pattern analysis of KcHTRs in this study. It provides the research basis and basis for further verification of gene function and mining and utilization of desert plant stress-resistance related gene resources.

Abstract:OsGRF6 belongs to the GRF family and is involved in the regulation of plant growth and development and tolerance to abiotic stress. In order to study the molecular mechanism of OsGRF6 to regulate the primary root development of rice, the transcription factor gene OsGRF6 was cloned from the rice variety ''ZH11''. The evolutionary tree construction and promoter analysis were carried out. The genotype analysis, qRT-PCR identification and rice phenotype observation of OsGRF6-OE and osgrf6 were carried out. The binding sequence of OsGRF6 was detected through yeast one-hybrid assays, and the candidate target genes downstream of OsGRF6 were further analyzed through ChIP-seqs and RNA-seqs data. The results show that: (1) OsGRF6 contains a QLQ and a WRC conservative functional domain, which is closely related to AtGRF1 and AtGRF2 and OsGRF7. The OsGRF6 promoter region contains multiple abiotic stress and hormone response cis-action elements. (2) OsGRF6 showed a higher level of expression in rice seeds, young spikes and roots than in leaf. Subcellular localization shows that OsGRF6 is located in the nucleus, and OsGRF6 has transcription activation activity. (3) Compared with wild types, overexpression of OsGRF6 transgenic plant materials show a longer primary root length, while loss of function mutant osgrf6 show a shorter phenotype of primary roots. (4) OsGRF6 can bind to CGGCA sequence. (5) Combined with ChIP-seqs and RNA-seqs analysis, it is found that a number of the OsGRF6 target genes were involved in regulating rice root development, such as OsARF7 and OsARF4, etc.

Abstract:The absorption and utilization of phosphate by plants mainly depend on phosphorus transporters, among which the low-affinity phosphorus transporters encoded by the PHT2 family are mainly responsible for the absorption, transport and reuse of phosphate by plants under normal phosphorus supply conditions. In order to explore the role and expression mode of low-affinity phosphorus transporter gene NtPHT2;1 in tobacco phosphate transport, this study cloned NtPHT2;1 using the cDNA of common tobacco K326 as a template, and conducted bioinformatics analysis of the gene and subcellular localization of the protein. The expression patterns of this gene under abiotic stress such as low phosphorus were analyzed by fluorescence quantitative PCR. The results showed that: (1) The total length of NtPHT2;1 gene is 1 764 bp and encodes 587 amino acids. (2) The results of subcellular localization showed that NtPHT2;1 protein was localized on chloroplasts. (3) Homology analysis showed that the homology between NtPHT2;1 protein and CaPHT2;1 protein reached 91.00%. (4) Promoter analysis showed that NtPHT2;1 promoter contains cis-acting elements involved in the regulation of plant aging and stress. (5) Tissue expression pattern analysis showed that the expression level of NtPHT2;1 was the highest in leaves, and the expression level in new leaves was higher than that in old leaves. There was no significant difference in the expression of this gene under low phosphorus induction compared with normal conditions. (6) The expression patterns under different abiotic stresses showed that the expression of this gene decreased significantly under salt stress and drought stress. It is concluded that NtPHT2;1 gene is mainly responsible for phosphate transport and utilization under normal growth and development of tobacco plants.

Abstract:In order to reveal the physiological response of sunflower to broomrape parasitism and its related metabolic pathways, the resistant-broomrape sunflower material (s41) and the sensitive-broomrape sunflower material (s26) were used as the test materials to inoculate the broomrape. Transcriptome sequencing analysis of 4 samples under the condition of parasitic stress in broomrape was carried out, and physiological verification analysis of some key substances was carried out. The results showed that the number of DEGs was 6362, 6609, 5490 and 5469 by screening the differential genes among the samples. GO analysis showed that the s26-s41, s26CK-s41CK, s26-s26CK, and s41-s41CK 4 comparison groups had more differential genes involved in biological processes, followed by cellular components, and less involved in molecular functions; KEGG analysis showed that Infection has a great influence on plant signal transduction, biosynthesis of secondary metabolites, lipid metabolism, amino acid metabolism and sugar metabolism in sunflower. The measurement results of physiological indicators showed that the enzymes involved in phenylpropane metabolism, antioxidant substances, and salicylic acid all showed an upward trend, indicating that under the parasitism of broomrape, the anti-stress system was activated, but the physiological indicators related to sense and anti-materials changed. The difference is that the gene expression that controls the relevant physiological indicators is different. The results laid the foundation for revealing the molecular mechanism of resistance broomrape.

Abstract:Abstracts: In order to establish an efficient and stable genetic transformation system of Lycium ruthenicum, effectively reduce the vitrification rate of regenerated seedlings, promote the study of gene function and improve the efficiency of genetic improvement. In this paper, the leaves of Lycium ruthenicum were used as explants, and the genetic transformation method mediated by Agrobacterium (LBA4404, EHA105) was used, which adjusted the type of basic medium, added the corresponding concentration of plant hormones, screened out the optimal callus induction medium, differentiation and selection medium and rooting induction medium. The genetic transformation rate of Lycium ruthenicum increased to more than 65%, and the vitrification rate of seedlings decreased to less than 10%. In this combination culture system lays an important foundation for molecular breeding of Lycium ruthenicum. The results showed that: (1) The optimal Agrobacterium infection concentration ( OD600 ) was 0.6 and the infection time was 25 min in the efficient combination culture system of Lycium ruthenicum leaves. Under this condition, the infected leaves were placed in the callus induction medium, and the resistance callus induction rate was 78.2%-96%;(2) The optimum differentiation and selection culture medium for genetic transformation of Lycium ruthenicum was : MS + inositol 50 mg / L + nicotinic acid 0.25 mg / L + VB6 0.25 mg / L + Fe salt mother liquor 1 mL / L + glycine 1.0 mg / L + VB1 0.05 mg / L + 6-BA 0.25 mg / L + sucrose 30 g / L + agar 6 g / L + Kanamycin 30 mg / L + Timentin 300 mg / L ( pH = 6.0 ) ;The optimal rooting culture medium was WPM + IBA 0.25 mg / L + sucrose 30 g / L + agar 6 g / L + Kanamycin 30 mg / L + Timentin 300 mg / L ( pH = 6.0 ).(3) In the optimal differentiation and selection culture medium, the seedling vitrification rate infected by Agrobacterium LBA4404-pBI121 was about 65 %, while the seedling vitrification rate infected by Agrobacterium EHA105-pBI121 was less than 10 %.(4) The rooting efficiency of regenerated seedlings of Lycium ruthenicum could reach about 81.2 % by using low-salt WPM medium of woody plants. (5) The ratio of the number of positive callus to the total number of inoculated leaves was used as the evaluation index of genetic transformation efficiency. In the optimal genetic transformation system, the genetic transformation rates of Agrobacterium LBA4404-pBI121 and EHA105-pBI121 were 51% and 65.2%, respectively. The efficient combination culture system of Lycium ruthenicum leaves can significantly improve its genetic transformation rate and reduce the incidence of vitrified seedlings.

Abstract:In order to explore the adaptation mechanism of Cyclobanopsis glauca seedlings to "drought-rehydration" environment in karst area, using the current growth seedlings of C. glauca as materials, the pot water control experiment was carried out. The effects of four soil drought stress treatments (control (–0.1 MPa), mild drought (－0.5 MPa)), moderate drought (–0.9 MPa) and severe drought (–1.5 MPa)) and rehydration treatments on water status, photosynthesis, chlorophyll fluorescence and anatomical structure parameters of leaves were studied. Results show that: (1) With the increase of drought stress intensity, leaf relative water content, water potential, net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs) and intercellular CO2 concentration (Ci) were significantly decreased, and stomatal limitation (Ls) increased significantly. Photosynthetic parameters under mild stress and instantaneous water use efficiency (WUE) under mild and moderate drought stress were not significantly affected. After rehydration, leaf water parameters, Pn, Tr, Gs, Ci and WUE under each drought stress treatment were were higher than those before rehydration, while Ls was lower than those before rehydration.. The leaf water conditions and photosynthetic parameters under mild drought stress were significantly better than those of the control after mild stress rehydration, only Ls under moderate drought stress did not recover to the level of the control after rehydration, and neither leaf water content nor photosynthetic parameters under severe drought stress recovered to the level of the control after rehydration. (2) With the increase of drought stress intensity, the initial fluorescence (Fo) of leaves increased significantly, while the maximum fluorescence (Fm), maximum photochemical quantum yield (Fv/Fm) and potential photochemical efficiency (Fv/Fo) of leaves decreased significantly. There were significant differences in these parameters between mild drought stress and control. After rehydration, Fm, Fv/Fm and Fv/Fo under each drought stress were higher than those before rehydration, whereas Fo was slightly lower than that before rehydration. All the chlorophyll fluorescence parameters after rehydration under mild stress recovered to or better than those of the control. Fo under moderate and severe drought stress did not return to the control level after rehydration, and Fv/Fm under severe stress was only 0.75 after rehydration. (3) With the increase of drought stress intensity, leaf thickness, upper and lower epidermis thickness, stomatal density, and main vein conduit diameter increased significantly, length and width of stomatal apparatus, stomatal opening area and sponge tissue thickness decreased significantly, while palisade tissue thickness, ratio of palisade tissue thickness to spongy tissue thickness and main vein thickness were moderate > mild > control > severe drought stress. After rehydration, only the stomatal opening area and the thickness of main leaf veins of each drought stress increased significantly compared with that before rehydration. After rehydration, the leaf structural parameters under mild drought stress were restored to or better than those in the control. The stomatal opening area after rehydration in moderate drought stress was still significantly lower than that in the control group. After rehydration, the stomatal opening area in severe drought stress failed to recover, and the thickness of main veins in severe drought stress was lower than that in the control. Therefore, the seedlings of C. glauca have drought tolerance and post-drought recovery ability, which is suitable for ecological restoration tree in karst area, but the seedlings should be protected from moderate drought stress (-0.9mpa) in the nurturing stage, so as to facilitate their post-drought recovery.

Abstract:In order to understand the leaf functional traits of desert plant and their ecological adaptability to different habitats conditions in Minqin region, Taking Calligonum mongolicum as the research object, this paper compared and analyzed the leaf functional traits and correlation of Calligonum mongolicum under two microtopography conditions: interdune lowland and mobile dune, and revealed the relationship between leaf functional traits and soil factors. The results showed that: (1) The coefficient variation of leaf functional traits was between 2.39% and 24.94%, the coefficient variation of specific leaf area (SLA) was the largest (24.94%), and the coefficient variation of stable carbon isotope (δ₁₃^C) was the smallest (2.39%). There were significant differences in total carbon (LCC) and total phosphorus (LPC) of Calligonum mongolicum leaves between different succession stages (P<0.05), while there were significant differences in specific leaf area (SLA) and total phosphorus (LPC) between different habitats (P<0.05). (2) The leaf water content (LWC) and leaf dry material content (LDMC) were extremely significant (P<0.01) and significant (P<0.05) negatively correlated under the two habitats conditions, respectively. Leaf water content (LWC) was the top three common index factor in the comprehensive ranking of leaf functional traits of Calligonum mongolicum under the two habitats conditions. (3) Soil total nitrogen content (STN), pH value and soil moisture content (SMC) were the main soil factors affecting the variation of leaf functional traits. The results provide a scientific basis for the restoration of desert vegetation and species protection, and provide a theoretical reference for exploring the resource utilization strategies and adaptation mechanisms of plants in the arid desert region.

Abstract:In order to explore the impact of uranium on algae growth and photosynthesis, and screen new and based on photosynthetic ecological risk assessment indicators for uranium pollution in water bodies, this experiment used different concentrations of uranium (0, 0.5, 1, 5, 10, 20mg U·L-1) to treat two types of microalgae from different growth environments, Chlorella vulgaris and Huanglong Chlorella vulgaris. The relative growth rate, photosynthetic oxygen release rate, chlorophyll content, and chlorophyll fluorescence kinetic parameters were measured on the 3rd, 5th, 7th, 10th, and 14th days after treatment. The results showed that: (1) 0.5mg·L-1 low concentration uranium treatment significantly promoted the growth and photosynthetic efficiency of two types of microalgae, manifested as the relative growth rate, photosynthetic oxygen release rate, maximum photochemical quantum yield (Fv/Fm) of photosystem II, actual photochemical quantum yield Y (II), and relative electron transfer rate rETR of the two microalgae being significantly higher than the control, however, high concentration uranium treatment of 5-20 mg·L-1 significantly inhibited the growth and photosynthesis of two types of Chlorella. (2) Huanglong Chlorella vulgaris is more sensitive to uranium treatment than Chlorella vulgaris, and its growth and photosynthesis are significantly inhibited at a concentration of 1mg·L-1, and it can be used as an bioindicator for biological monitoring of uranium pollution in water bodies; (3) Regression analysis shows that under different concentrations of uranium treatment, the response speed of chlorophyll fluorescence parameters Y (II) and rETR is faster than the changes in relative growth rate, photosynthetic oxygen release rate, chlorophyll content, and Fv/Fm, which can be used as sensitive indicators for ecological risk assessment of uranium pollution in water bodies.

Abstract:The survival of species seedlings is closely related to various biotic and abiotic factors. Exploring the effect of key factors on seedling survival can help us to understand species coexistence mechanisms. This study was focused on the woody species seedlings in a 25 hm2 permanent forest dynamics plot in the deciduous broad-leaved forest in the Qinling Mountains, and the generalized linear mixed models (GLMMs) were used to explore the effect of main biotic and abiotic factors on seedling survival. Our results showed that: (1) At the community level, biotic factors played a major role on seedling survival. Seedling survival was significantly negatively correlated with conspecific seedling density and conspecific adult. It also positively correlated with interspecific seedlings density. The results showed that negative density-dependence (NDD) had significant effects on seedling dynamics. (2) At the age class, in addition to biological factors, abiotic factors such as altitude also affected seedling survival. The effect of abiotic factors decreased with the increase of seedling age. In summary, there were various factors affecting seedling survival, among which biological factors were more significant, the main mechanism promoting seedling coexistence was negative density restriction effect in the Qinling Mountains.

Abstract:Callose is a beta-1, 3-bonded glucan that forms a wall structure that occurs only in certain tissues. When it is degraded prematurely or delayed, it will lead to pollen abortion. It is important to clarify the dynamic law of callose deposition for exploring the mechanism of male sterility and using barbary wolfberry male sterility. In this study, using Lycium barbarum L. fertile line ‘Ningqi 1’ and sterile line ‘Ningqi 5’ as experimental materials, using half thin slice technology, and using aniline blue mark callose and high iodine acid-shiff reaction (Periodic Acid-Schiff stain, PAS), under the optical microscope comparison and sterile lines Lycium barbarum L. anthers different development lose dynamic characteristics, and analyzed the influence of callose on sterile anther abortion. The results showed that in the period of microspore mother cell, both the fertile lines and the sterile lines could form a red callose wall, and the fluorescent reaction indicates that the corpus callose wall gradually thickened after the further development of the anther, the corpus callose wall gradually disintegrated and disappeared, releasing four microspores, while the callose wall of the sterile anthers continuously thickened without degradation, up to flowering , the deformed and disintegrated four branches still cover the callose wall, and the microspores still exist in the quad state. Abnormal callose degradation is the structural cause of pollen abortion in Lycium barbarum L. This paper further analyzed the reasons for the absence of callose wall degradation of the sterile line tetrad, which provides a theoretical basis for analyzing the mechanism of male sterility of Lycium barbarum L.

Abstract:The study of genetic diversity in oat germplasm resources not only contributes to the collection and evaluation of germplasm resources, but also has important guiding significance for the production and breeding of oats. This study analyzed the diversity, variation, and clustering of 20 morphological traits in 260 oat germplasm resources, evaluated the genetic variation level of their morphological traits, and clarified the characteristics and genetic diversity of oat germplasm resources, aiming to provide a basis for oat germplasm innovation and variety improvement. The results showed that there was a significant genetic diversity of morphological traits in the 260 oat germplasm resources. The genetic diversity index of quality traits was the highest in grain color (1.53) and the lowest in awn color (0.76). The genetic diversity index of the 12 quantitative traits was normally distributed, and the genetic diversity index of quantitative traits was the largest in thousand grain weight (2.03) and the smallest in effective tillers (1.22). The highest coefficient of variation was the effective tillering number (89.02%), and the lowest was the plant height (11.19%). According to genetic difference of each characteristic varieties, the 260 accessions should be classified into 6 categories by cluster analysis. Germplasm group I includes 42 materials which can be used as parent materials for seed type selection purposes. Germplasm group II has 31 materials that can be used as parent materials for breeding high-yield forage varieties. Germplasm group IV includes 41 materials that can be used as breeding materials for breeding large grain specific varieties. Germplasm group V includes 46 materials that can be used as parents for oat dwarfing. Germplasm Group III includes 46 materials, while Germplasm Group VI includes 54 materials, and the comprehensive properties of these two germplasm groups were not outstanding. This study can provide theoretical basis for the protection, development and utilization of oat germplasm resources in eastern Inner Mongolia.

Abstract:Plants in the Vallisneria genus have similar external morphologies, with linear or strap-shaped leaves, making it difficult to directly identify species in the field. But the number of stamens in the male flowers is one of the distinguishing characteristics of species in Vallisneria Linn. The male flowers of Vallisneria species are small, measuring only 1.5 mm. Identifying the number of stamens in these male flowers through manual dissection and observation methods can be challenging. This study utilized a hydroponic pre-culture method with male plants and male flower primordia of Vallisneria to obtain naturally opened male flowers. Anatomical observations and research on the male flowers, fruits, and seeds of three Vallisneria species were conducted using anatomical microscopes.Microscopic observations revealed that in V. natans, there is one stamen in the male flowers. The fruits are cylindrical in shape, with a smooth surface, and the seeds are wingless but have longitudinal stripes. In V. spinulosa, there are two stamens in the male flowers. The fruits are triangular in shape, with spines along the edges, and the seeds have wings. In V. denseserrulata, there are also two stamens in the male flowers. The fruits are cylindrical with three edges, have a smooth surface, and the seeds are wingless.Based on literature and introduction cultivation experiments, V. denseserrulata, V. spinulosa, V. longipedunculata and V. anhuiensis are reported as new distribution records of Vallisneria Linn in Anhui Province. Among them, V. longipedunculata and V. anhuiensis are new species found in Anhui.

Abstract:Colquhounia coccinea shows a floral syndrome typical of bird pollination, and therefore has the potential to be developed as a bird-attracting landscape plant. Taking the C.?coccinea population in natural and artificial habitat as the research object, the flowering phenology, flower traits, flower visitor and flower visiting behavior, breeding system, and seed germination traits are studied through observation and experiment, so as to clarify the reproductive traits of the C.?coccinea and the attraction potential of different flower visitors. The results showed that the flowering season of C.?coccinea lasted for about three months, the single flowering period was 9.6±0.6 d; nectar was relatively abundant and dilute, with short corolla tubes and hexose-dominated nectar sugar composition; flower visitors were mainly Apis cerana and a variety of nectarivorous birds, especially short-billd generalized birds, and C.?coccinea still attracted bird visitors in artificial habitats; it is completely self-compatibile, but pollinators were necessary for pollination, and pollen limitation did not exist; there was no significant difference in seed germination ability among the pollination treatments; Apis cerana can pollinate it effectively, and the pollination effectiveness of birds needs to be further verified. In summary, C.?coccinea shows a long display season and, has an apparent ability to attract birds to visit the flowers. We can produce large numbers of seedlings via sexual reproduction.

Abstract:Based on the data of groundwater depth in the Daliyaboyi oasis at the hinterland of Taklimakan Desert, this study analyzed the variation of tree-ring width of Tamarix spp. and discussed the relationship between tree-ring width and groundwater depth. Results showed that the groundwater depth of the first sample site increased year by year with time, and the ranges were 1.2-2.6 m. Tree-ring width of Tamarix spp. increased significantly from 2001 to 2020 with a range of 0.98-5.80 mm at the first sample site, and the interannual differences of tree-ring width were significant. The ranges of groundwater depth of the second sample site were 2.7-4.5 m, which increased first and then decreased with time. The tree-ring width of Tamarix spp. at the second sample site changed as a sine function from 1977 to 2020, ranged from 1.46 mm to 4.41 mm, with no significant interannual difference. The amplitude of Tamarix spp. standard chronology ranged from 0.502 to 1.641 at the first sample site, which were larger than at the second sample site with the range of 0.577-1.331. The above results showed that a moderate increase in groundwater depth was beneficial to Tamarix spp. growth at the first sample site, supported by the increase of tree-ring width. There was no significant correlation between the tree-rings width and the groundwater depth of the second sample site. The results are helpful to understand the radial growth of Tamarix spp. under the condition of groundwater depth change.

Abstract:In order to analyze the response of plant functional group diversity and species abundance distribution to degradation in the alpine meadow of Gannan, and to explore the formation and maintenance mechanism of the diversity, data were collected by sample plot survey method, and the species abundance model was used for fitting analysis. The results showed that the dominant vegetation species were mainly grass and sedge, and gradually changed to weed functional groups, which played a leading role in the distribution of community diversity. The distribution of species abundance changed with the deterioration degree. The optimal fitting model of non-degraded meadow was VOLKOV, the optimal fitting model of mildly degraded meadow was GEO, and the optimal fitting model of moderately degraded meadow and severely degraded meadow was BRO. The distribution mode of resource allocation changed from random allocation to fixed allocation. The optimal fitting model of grass functional groups is mainly niche model, and the resource allocation mode is dominated by fixed allocation and random allocation. The optimal fitting model of leguminous functional groups is BRO, and the resource allocation mode is mainly fixed allocation. The optimal fitting model of weed functional groups changes from neutral model to niche model, which is basically consistent with the optimal model of all species abundance distribution. In addition, the resource allocation changed from random allocation to fixed allocation, so it can be considered that weed functional groups were the main factors affecting the distribution of community species abundance, but the contribution of grass and leguminous functional groups could not be ignored.

Abstract:【Objective】 The Yarlung Zangbo River is the most important river on the Tibetan Plateau, and the study of aboveground biomass and species diversity of the Yarlung Zangbo River is of great significance to the understanding of grassland resources and ecological conservation in the region. 【Methods】 This study investigated the vegetation characteristics of alpine meadows in the upper reaches of the Yarlung Zangbo River according to the elevation gradient, and studied the distributional differences of aboveground biomass and species diversity at different elevation gradients, the relationship between aboveground biomass and species diversity, and the effects of related environmental factors on aboveground biomass and species diversity. 【Results】 (1) There was no significant relationship between elevation and aboveground biomass. (2) Elevation and diversity indices showed a significant negative correlation: the Shannon-Weiner index and Patrick index showed a decreasing trend with elevation. (3) Aboveground biomass and diversity showed a negative correlation, and the explanation of aboveground biomass by the Shannon-Weiner index reached 70% (P<0.01). (4) Species diversity showed a significant positive correlation with temperature and precipitation (P<0.05), species diversity showed a negative correlation with elevation (P<0.05), and aboveground biomass had no significant relationship with elevation, temperature and precipitation (P>0.05). 【Conclusion】 The results of this study can help to improve the basis for the rational utilization of grassland resources and species diversity conservation in the upper Yarlung Zangbo River basin.

Abstract:Thylakoids are the important sites where photosynthesis takes place. The thylakoid membrane envelops a central aqueous region known as the thylakoid lumen. There are various types of proteins residing in thylakoid lumen including high chlorophyll fluorescence (HCF) protein, immunophilins, oxygen-evolving complex (OEC) proteins, PsbP-like proteins, etc. These proteins were considered to play important roles during various physiological processes, such as photosynthesis, nucleotide metabolism and redox regulation. This review systematically summarizes the function of thylakoid lumen proteins involved in photosynthesis regulation, such as photosystem assembly, growth regulation and excess light stress response, and provides the theoretical reference for future study on the physiological function of thylakoid lumen proteins.