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A perfect educational resource management system can effectively improve learner efficiency and reduce unnecessary waste of manpower and material resources. For this, using JSP website development technology, this paper studies the design and implementation of educational resource management system based on JSP technology. Through the analysis for the needs of educational resource management system, the functional composition of each module in the system was determined. Besides, the architecture, interface, fore-end function module and backstage management module were designed and implemented in detail. The test results of the system indicate that this system basically meets the preliminary design requirements and can realize the effective management of educational resources; but it can also be further optimized from the aspects of program structure and algorithm quality etc. This study provides methods and ideas for building a more efficient educational resource management system, and has a certain role in promoting the intelligent construction of educational resources management. [ABSTRACT FROM AUTHOR]

The present study aimed to characterize the simple sequence repeat markers in cotton using the cotton expressed sequence tags. A total of 111 EST-SSR polymorphic molecular markers with trinucleotide motifs were used to evaluate the 79 accessions of Gossypium L., (G. darwinii, 59 and G. barbadense, 20) collected from the Galapagos Islands. The allele number ranged from one to seven, with an average value of 2.85 alleles per locus, while polymorphisminformation content values varied from 0.008 to 0.995, with an average of 0.520. The discrimination power ranks high for the majority of the SSRs, with an average value of 0.98. Among 111 pairs of EST-SSRs and gSSRs, a total of 49markers, comprising nine DPLs, one each of MonCGR, MUCS0064, and NAU1028, and 37 SWUs (D-genome), were found to be the best matched hits, similar to the 155 genes identified by BLASTx in the reference genome of G. barbadense, G. arboreum L., and G. raimondii Ulbr. Related genes GOBAR_DD21902, GOBAR_DD15579, GOBAR_DD27526, and GOBAR_AA04676 revealed highly significant expression 10, 15, 18, 21, and 28 days post-anthesis of fiber development. The identified EST-SSR and gSSR markers can be effectively used for mapping functional genes of segregating cotton populations, QTL identification, and marker-assisted selection in cotton breeding programs. [ABSTRACT FROM AUTHOR]

The extrusion of toxins and substances at a cellular level is a vital life process in plants under abiotic stress. The multidrug and toxic compound extrusion (MATE) gene family plays a large role in the exportation of toxins and other substrates. We carried out a genome-wide analysis of MATE gene families in Gossypium raimondii and Gossypium arboreum and assessed their expression levels under salt, cadmium and drought stresses. We identified 70 and 68 MATE genes in G. raimondii and G. arboreum, respectively. The majority of the genes were predicted to be localized within the plasma membrane, with some distributed in other cell parts. Based on phylogenetic analysis, the genes were subdivided into three subfamilies, designated as M1, M2 and M3. Closely related members shared similar gene structures, and thus were highly conserved in nature and have mainly evolved through purifying selection. The genes were distributed in all chromosomes. Twenty-nine gene duplication events were detected, with segmental being the dominant type. GO annotation revealed a link to salt, drought and cadmium stresses. The genes exhibited differential expression, with GrMATE18, GrMATE34, GaMATE41 and GaMATE51 significantly upregulated under drought, salt and cadmium stress, and these could possibly be the candidate genes. Our results provide the first data on the genome-wide and functional characterization of MATE genes in diploid cotton, and are important for breeders of more stress-tolerant cotton genotypes. [ABSTRACT FROM AUTHOR]

Cold stress is a potent abiotic stress resulting in cotton yield and fiber quality loss. We hypothesized that GhGTG1 could increase low temperature stress tolerance by improving the sensitivity to ABA. Genome-wide identification, biochemical traits and functional characterization of GhGTG1 , were investigated under different levels of ABA and cold stress. GhGTG1 had two highly conserved functional domains (ABA_GPCR, GPHR_N) in all cotton species. Under ABA treatment, over expression of GhGTG1 in Arabidopsis had a lower germination rate and root elongation. While under 4 ℃ stress, transgenic plants had a higher germination rate and root elongation. This indicate that GhGTG1 improved sensitivity to ABA under cold stress. In transgenic plants, CAT and SOD activity was increased, while H 2 O 2 and MDA content decreased. Less trypan blue and DAB staining area suggested that GhGTG1 enhances cold stress resistance. Under 4 ℃ treatment, silence cotton seedlings through VIGS method, resulted in a poor growth, lower relative leaf water content, chlorophyll content but a higher ion leakage and excised leaf water loss. The activity of CAT and SOD decreased, H 2 O 2 and MDA content was increased. Two marker genes (OST1 and ABCG40) are associated with the stomatal movement, but these genes were substantially suppressed. This suggesting that GhGTG1 can induce cold stress tolerance by improving ABA sensitivity Via., maintaining stomatal movement. These data will provide new insight of cold resistance mechanism in cotton and further will help the breeder to develop new cotton cold stress tolerance germplasm. [Display omitted] • GhGTG1 increased ABA sensitivity to improve cold stress tolerance in Arabidopsis. • GhGTG1 can improve cold tolerance by regulating stomata opening and closure through ABA pathway in cotton. • GhGTG1 can induce cold stress tolerance by improving ABA sensitivity to control the stomatal movement. [ABSTRACT FROM AUTHOR]

Background: Chromosome microdissection is one of the most important techniques in molecular cytogenetic research. Cotton (Gossypium Linnaeus, 1753) is the main natural fiber crop in the world. The resistance gene analog (RGA) cloning after its single chromosome microdissection can greatly promote cotton genome research and breeding. Results: Using the linker adaptor PCR (LA-PCR) with the primers of rice disease-resistance homologues, three nucleotide sequences PS016 (KU051681), PS054 (KU051682), and PS157 (KU051680) were obtained from the chromosome Ah01 of upland cotton (cv. TM-1). The Blast results showed that the three sequences are the nucleotide binding site-leucine rich repeat (NBS-LRR) type RGAs. Clustering results indicated that they are homologous to these published RGAs. Thus, the three RGAs can definitely be confirmed as NBS-LRR class of RGAs in upland cotton. Conclusions: Using single chromosome microdissection technique, DNA libraries containing cotton RGAs were obtained. This technique can promote cotton gene cloning, marker development and even the improvement of cotton genome research and breeding. [ABSTRACT FROM AUTHOR]

Background: Dissecting genome organization is indispensable for further functional and applied studies. As genome sequences data shown, cotton genomes contain more than 60% repetitive sequences, so study on repetitive sequences composition, structure, and distribution is the key step to dissect cotton genome. Results: In this study, a bacterial artificial chromosome (BAC) clone enriched in repetitive sequences, was discovered initiatively by fluorescence in situ hybridization (FISH). FISHing with allotetraploidy cotton as target DNA, dispersed signals on most regions of all A sub-genome chromosomes, and only middle regions of all D sub-genome chromosomes were detected. Further FISHing with other cotton species bearing A or D genome as target DNA, specific signals were viewed. After BAC sequencing and bioinformational analysis, 129 repeat elements, size about 57,172 bp were found, accounting for more than 62% of the BAC sequence (91,238 bp). Among them, a type of long terminal repeat-retrotransposon (LTR-RT), LTR/Gypsy was the key element causing the specific FISH results. Using the fragments of BAC matching with the identified Gypsy-like LTR as probes, the BAC-57I23-like FISH signals were reappeared. Running BLASTN, the fragments had good match with all chromosomes of G. arboreum (A2) genome and A sub-genome of G. hirsutum (AD1), and had relatively inferior match with all chromosomes of D sub-genome of AD1, but had little match with the chromosomes of G. raimondii (D5) genome, which was consistent with the FISH results. Conclusion: A repeats-enriched cytogenetic marker to identify A and D sub-genomes of Gossypium was discovered by FISH. Combined sequences analysis with FISH verification, the assembly quality of repetitive sequences in the allotetraploidy cotton draft genome was assessed, and better chromosome belonging was verified. We also found the genomic distribution of the identified Gypsy-LTR-RT was similar to the distribution of heterochromatin. The expansion of this type of Gypsy-LTR-RT in heterochromatic regions may be one of the major reasons for the size gap between A and D genome. The findings showed here will help to understand the composition, structure, and evolution of cotton genome, and contribute to the further perfection of the draft genomes of cotton. [ABSTRACT FROM AUTHOR]

Two bacterial artificial chromosome (BAC) clones (350B21 and 299N22) of Pima 90-53 cotton [Gossypium barbadense Linnaeus, 1753 (2n=4x=52)] were screened from a BAC library using SSR markers. Strong hybridization signals were detected at terminal regions of all A genome (sub-genome) chromosomes, but were almost absent in D genome (sub-genome) chromosomes with BAC clone 350B21 as the probe. The results indicate that specific sequences, which only exist at the terminal parts of A genome (sub-genome) chromosomes with a huge repeat number, may be contained in BAC clone 350B21. When utilizing FISH with the BAC clone 299N22 as probe, a pair of obvious signals was detected on chromosome 13 of D genome (sub-genome), while strong dispersed signals were detected on all A genome (sub-genome) chromosomes. The results showed that peculiar repetitive sequence, which was distributed throughout all A genome (subgenome) chromosomes, may exist in BAC clone 299N22. The absence of the repetitive sequences, which exist in the two BAC clones, in D genome may account for the genome-size variation between A and D genomes. In addition, the microcolinearity analysis of the clone 299N22 and its homologous region on G. raimondii Ulbrich, 1932 chromosome 13 (D513) indicated that the clone 299N22 might come from A sub-genome of sea island cotton (G. barbadense), and a huge number of small deletions, illegitimate recombination, translocation and rearrangements may have occurred during the genus evolution. The two BAC clones studied here can be used as cytological markers but will be also be helpful to research in cotton genome evolution and comparative genomics. [ABSTRACT FROM AUTHOR]

Background: Cytogenetic map can provide not only information of the genome structure, but also can build a solid foundation for genetic research. With the developments of molecular and cytogenetic studies in cotton (Gossypium), the construction of cytogenetic map is becoming more and more imperative. Results: A cytogenetic map of chromosome 1 (A101) of Gossypium herbaceum (A1) which includes 10 bacterial artificial chromosome (BAC) clones was constructed by using fluorescent in situ hybridization (FISH). Meanwhile, comparison and analysis were made for the cytogenetic map of chromosome 1 (A101) of G. herbaceum with four genetic linkage maps of chromosome 1 (Ah01) of G. hirsutum ((AD)1) and one genetic linkage map of chromosome 1 of (A101) G. arboreum (A2). The 10 BAC clones were also used to be localized on G. raimondii (D5) chromosome 1 (D501), and 2 of them showed clear unique hybridized signals. Furthermore, these 2 BAC clones were also shown localized on chromosome 1 of both A sub-genome and D sub-genome of G. hirsutum. Conclusion: The comparison of the cytogenetic map with genetic linkage maps showed that most of the identified marker-tagged BAC clones appearing same orders in different maps except three markers showing different positions, which might indicate chromosomal segmental rearrangements. The positions of the 2 BAC clones which were localized on Ah01 and Dh01 chromosomes were almost the same as that on A101 and D501 chromosomes. The corresponding anchored SSR markers of these 2 BAC clones were firstly found to be localized on chromosome D501 (Dh01) as they were not seen mapped like this in any genetic map reported. [ABSTRACT FROM AUTHOR]