Biomedical subjects

Chun-Hai Shi

Publications and source records attributed to Chun-Hai Shi.

9 recordsLinked to original sources

PubMed2006

[Study on developing calibration models of fatty acid composition in intact rapeseed by near infrared reflectance spectroscopy].

Four hundred ninety seven rapeseed samples, which feature multi-year, multi-loci and highly variant characteristics, were collected as a raw set. The NIR spectra were pretreated by scatter correction and mathematics treatments, and calibration models of fat acid composition of intact rapeseed were developed by using the algorithm method of modified partial least square (MPLS). Meanwhile, three types of sample cups with different capacity were used to screen the suitable calibration model for rapeseed quality breeding. The results showed that the calibration model of 8-gram-sample was the best, and the calibration determination coefficient was in the range of 0.74-0.98. The calibration effects of 3-gram-sample, which were similar to those of 0.6-gram-sample, were good with high determination coefficient (RSQ1, 1-VR) and low error (SEC, SECV). Therefore, the calibration set with multi-year and multi-loci samples can improve the accuracy and repeatability of NIRS models. The fat acids NIRS models of intact rapeseed developed could be introduced into breeding lines' selection, mutant screening and germplasm evaluation.

Brassica rapa↗

PubMed2006

[Creating a software package and improving the multimedia teaching of genetics course].

Multimedia as a pedagogical tool has been widely adopted for improving the quality of teaching. This paper describes the construction of a teaching software package based on the characteristics of the "Genetics" course. It also discusses some particulars of multimedia teaching, the collection of teaching materials, the improvement of teaching effects, and the compilation of a multimedia textbook. How to enhance the quality of the teachers as well as the motivation of the students are also discussed.

China↗

PubMed2005

Morphogenesis and molecular basis on naked seed rice, a novel homeotic mutation of OsMADS1 regulating transcript level of AP3 homologue in rice.

The floral organs are formed from floral meristem with a regular initiation pattern in angiosperm species. Flowers of naked seed rice (nsr) were characterized by the overdeveloped lemma and palea, the transformation of lodicules to palea-/lemma-like organs, the decreased number of stamens and occasionally extra pistils. Some nsr spikelets contained additional floral organs of four whorls and/or abnormal internal florets. The floral primordium of nsr spikelet is differentiated under an irregular pattern and an incomplete determination. And molecular analysis indicated that nsr was a novel homeotic mutation in OsMADS1, suggesting that OsMADS1 played a distinct role in regulating the differentiation pattern of floral primordium and in conferring the determination of flower meristem. The gain-of-function of OsMADS1 transgenic lines presented the transformation of outer glumes to lemma-/palea-like organs and no changes in length of lemma and palea, but loss-of-function of OsMADS1 transgenic lines displayed the overdeveloped lemma and palea. Both findings revealed that OsMADS1 played a role in specifying lemma and palea and acted as a repressor of overdevelopment of lemma and palea. Moreover, it was indicated that OsMADS1 upregulated the transcript level of AP3 homologue OsMADS16, using real-time PCR analysis on gain- and loss-of-function of OsMADS1 transgenic lines.

Arabidopsis Proteins↗

PubMed2005

Genetic diversity and population differentiation of Liaoning weedy rice detected by RAPD and SSR markers.

Weedy rice refers to populations of usually annual Oryza species that diminish farmer income through reduction of grain yield and lowered commodity value at harvest. The genetic diversity and population genetic structure of weedy rice in Liaoning Province were studied by RAPD and SSR markers. The results indicate that the level of genetic diversity of Liaoning weedy rice is very low, with polymorphic loci being only 3.70% (RAPDs) and 47.62% (SSRs). On the other hand, high genetic differentiation was found among populations, in particular between two regions (Shenyang and Dandong), with Fst values of 0.746 (RAPDs) and 0.656 (SSRs), suggesting that more than two thirds of the genetic variation resides among regions. Combined with our investigations of cultural traditions, the low level of genetic diversity in Liaoning Province is attributed to its narrow genetic background enhanced by exchanges of cultivar seeds, whereas the high genetic differentiation between the two regions is most likely the result of different founding parents and gene flow from local rice varieties to weedy rice. The rice cultivars in the two regions are all local varieties and are different genetically. A comparison of the two marker systems demonstrates that SSR is more informative and powerful in terms of the assessment of genetic variability, although both RAPD and SSR provide useful genetic information on weedy rice.

China↗

PubMed2005

[Establishment of Genic Male Sterile Lines of Brassica napus by Wide Cross and Their Cytology and Morphology.].

One and three male sterile plants were found in the progenies of the intergeneric hybrids by crossing Brassica napus and Brassica juncea to Orychophragmus violaceus, respectively. After interspecific cross and full-sib crosses, four genic male sterile lines were obtained. The results of cytological observations indicated that somatic chromosome number was 38 in all types of sterile lines, which were considered as the type of B. napus. Most of pollen mother cells (PMC) in all sterile plants were observed normally for chromosome behaviour. But abnormal phenomena of chromosome, which present for chromosome lagging and bridge, were still found at each stage of meiosis in these sterile lines. These lines belonged to complete sterile type. There were distinct differences between sterile plants and normal plants in the flower morphology. Bud death at different degrees was found on anthotaxies in sterile plants. Studies on the flower growth showed that the growths of the pistils in sterile plants were gradually accelerated along with pollen sterility. At the same time there were two slowly growth stages of the pistils growth in normal plants. The prospects of these sterile lines were discussed in this paper.

Brassica napus↗

PubMed2005

[Genetic diversity of flue-cured tobacco varieties based on ISSR markers].

Genetic diversity was assessed among 24 flue-cured tobacco varieties by ISSR (inter simple sequence repeats). A total of 100 ISSR primers were used to amplify the DNA from these varieties, of which 10 primers produced reproducible amplified products. Using polyacrylamide gel electrophoresis 208 bands were identified, of which 141 bands were polymorphic among the flue-cured tobacco varieties analyzed. Each primer produced 7-37 bands, the length of which ranged 200-2,400 bp. The ratio of polymorphic bands (PPB) was 67.79%. By cluster analysis based on ISSR markers using UPGMA, 24 varieties were divided into 5 major groups, in which the biggest group consisted of 12 varieties derived from Coker319. The genetic similarity index was 0.66-0.85 among 24 flue-cured tobacco varieties. Low genetic diversity among flue-cured tobacco varieties suggested that it is necessary to expand the genetic base of the flue-cured tobacco. 24 varieties could be distinguished by using 2 ISSR markers. The result also indicated that ISSR analysis was suitable for varietal identification and the study on genetic diversity of tobacco germplasm.

DNA, Plant↗

PubMed2005

[Improvement and optimization for "genetics" course teaching].

"Genetics" is one of the main courses for the study scheme of undergraduate students in university. This paper pointed out some problems found in the teaching process according to the characteristics of "Genetics" course. At the same time, the thought on the construction of "Genetics" course were discussed concerning the reform of course contents, the improvement of teaching method, the creation of teaching CAI (computer assisted instruction), the compile of electronic edition for teaching materials, the evaluation of teaching level, the innovation of experimental contents and the methods for improving the teaching effect.

Computer-Assisted Instruction↗

PubMed2004

[Hypoploid groups and their cytogenetic analysis in the progenies between Brassica napus and Orychophragmus violaceus].

Several groups of hypoploids were characterized in pentaploid (p) progenies of B. napus and O. violaceus. Cytological characterization of the P3 population revealed allosubstitution of one pair of B. napus chromosomes with O. violaceus chromosomes. This population had normal fertility and had three kinds of somatic cells with 36-38 chromosomes. Its somatic cells and pollen mother cells (PMC) mainly had 38 chromosomes. From a P4 population, three monosomic plants with 37 chromosomes were identified with differing morphology and fertility. One plant which grew vigorously was composed of various types of somatic cell and PMC, in which the cells with 37 chromosomes were observed mainly. The unpaired chromosome was small and with no negative effects on plant development. In the offsprings of the aneuploids (P3) with 41-44 chromosomes, there are four types of plants with 29-32 chromosomes. Except the plant with 29 chromosomes, others which appeared abnormal meiosis behavior and poor pollen fertility are mixoploid. The origin of these hypoploids and their prospects of application have been discussed.

Aneuploidy↗

PubMed2002

[Developmental genetic analysis for transparency of rice (Oryza sativa L.) at different environments].

The developmental behavior of gene expression for transparency of rice (TR) was analyzed from two-year experimental data at different filling stages by using both conditional and unconditional analysis methods for quantitative traits of seeds in cereal crops. It was revealed that the gene expression was most active for the performance of TR at the middle and late filling stages (8-21 d after flowering). The differences of expression at different environments for triploid endosperm nuclear genes, cytoplasmic genes and diploid maternal plant nuclear genes were found for the performance of TR. The phenomena of which some genetic effects were spasmodically expressible were detected among filling stages of rice. Because of the higher additive and cytoplasmic effects along with their interaction effects for TR at the filling stages, the better improving effects for this trait could be expected by selection in rice breeding. Some parents such as Zhenan 3 and 1391 were better than others for improving TR.

Environment↗