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Chengjiang Ruan
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ABSTRACT: In the past 20 years, the major effort in plant breeding has changed from quantitative to molecular genetics with emphasis on quantitative trait loci (QTL) identification and marker assisted selection (MAS). However, results have been modest. This has been due to several factors including absence of tight linkage QTL, non-availability of mapping populations and lack of substantial time needed to develop such populations. To overcome these limitations and as an alternative to planned populations, molecular marker-trait associations have been identified by the combination between germplasm and the regression technique. In the present preview, we first surveyed the successful applications of germplasm-regression-combined (GRC) molecular marker-trait association identification in plants; secondly, we described how to do the GRC analysis and its differences from mapping QTL based on a linkage map reconstructed from the planned populations; thirdly, we considered the factors that affect the GRC association identification, including selections of optimal germplasm and molecular markers and testing of identification efficiency of markers associated with traits; and finally we discussed the future prospects of GRC marker-trait association analysis used in plant MAS/QTL breeding programs, especially in long-juvenile woody plants when no other genetic information such as linkage maps and Quantitative Trait Loci are available.
AFRICAN JOURNAL OF BIOTECHNOLOGY ; 9:573-580. · 0.57 Impact Factor
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Chinese Science Bulletin 04/2012; 50(1):94-96. · 1.32 Impact Factor
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ABSTRACT: Taxus suspension cell culture has the potential to provide a sustainable source of anticancer drug paclitaxel (Taxol) and other taxoids. In the cell culture of Taxus chinensis, Taxuyunnanine C (Tc) is the primary taxoid. To design a rational strategy for redirecting the precursor fluxes from other taxoids into paclitaxel production, we employed Real-time Quantitative PCR (RQ-PCR) to understand the dynamic profiling of key biosynthetic pathway genes of palcitaxel and taxoids during the culture process. Six genes (TASY, TDAT, T5alphaH, TalphaH, T10betaH and T14betaH) were quantified under the process condition of double elicitation by 2,3-dihydroxylpropanyl jasmonate (DHPJA) (100 micromol/L on day 7 and day 12), and sucrose feeding (20 g/L) on day 7. This process treatment led to a high accumulation of Tc at (554.46 +/- 21.28) mg/L 8 days after the first elicitation. Then 9 days after the second elicitation, Tc production was as high as (997.72 +/- 1.51) mg/L. The early pathway genes TASY and TDAT were significantly up-regulated by 182-fold and 98-fold, respectively for the first DHPJA elicitation and by 208-fold and 131-fold, respectively for the second elicitation. The induction occurred after each elicitation lasted for about 24 h before their abundances decreased. Things are somewhat different in the case of the other four genes T5alphaH, TalphaH, T10betaH and T14betaH. For gene TalphaH, it was highly up-regulated by 3061-fold for the first DHPJA elicitation and by 1016-fold for the second elicitation. For the other three genes T5alphaH, T10betaH, T14betaH, they were up-regulated by 13-fold, 38-fold and 20-fold, respectively for the first DHPJA elicitation and by 7-fold, 16-fold and 6-fold, respectively for the second elicitation. The RQ-PCR results showed that there is tight correlation between gene expression and Tc accumulation. Gene expression was in accordance with Tc yield. Elicitation could improve expression of six genes. While along with culture course, high expression of the genes weakened. Elicitation for the second time would promote high expression of the genes again.
Sheng wu gong cheng xue bao = Chinese journal of biotechnology 01/2011; 27(1):101-7.
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ABSTRACT: Mechanism of four methods for removing hazardous heavy metal are detailed and compared-chemical/physical remediation, animal remediation, phytoremediation and microremediation with emphasis on bio-removal aspects. The latter two, namely the use of plants and microbes, are preferred because of their cost-effectiveness, environmental friendliness and fewer side effects. Also the obvious disadvantages of other alternatives are listed. In the future the application of genetic engineering or cell engineering to create an expected and ideal species would become popular and necessary. However, a concomitant and latent danger of genetic pollution is realized by a few persons. To cope with this potential harm, several suggestions are put forward including choosing self-pollinated plants, creating infertile polyploid species and carefully selecting easy-controlled microbe species. Bravely, the authors point out that current investigation of noncrop hyperaccumulators is of little significance in application. Pragmatic development in the future should be crop hyperaccumulators (newly termed as "cropaccumulators") by transgenic or symbiotic approach. Considering no effective plan has been put forward by others about concrete steps of applying a hyperaccumulator to practice, the authors bring forward a set of universal procedures, which is novel, tentative and adaptive to evaluate hyperaccumulators' feasibility before large-scale commercialization.
Journal of hazardous materials 09/2009; 174(1-3):1-8. · 4.14 Impact Factor
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ABSTRACT: Kosteletzkya virginica exhibits a delayed autonomous selfing mechanism by stigma lobe curvature. To measure the contribution of delayed selfing to reproductive success in a naturalised population of K. virginica, we evaluated the capacity for autonomous self-pollination and compared reproductive success of intact with emasculated open-pollinated flowers. We found no significant differences in the mean number of pollen grains deposited per flower and per stigma between the autonomously pollinated and open-pollinated flowers. There were no significant differences in mean fruit set and in mean number of seeds per capsule between autonomous and hand self-pollination. Fruit set following self-pollination varied significantly depending on the timing of pollination within a day. Emasculation and pollination treatments did not significantly affect fruit set. In contrast, the mean number of seeds per capsule from intact open-pollinated flowers was higher than that of emasculated open-pollinated flowers. These results indicate that K. virginica has a well-developed capacity for delayed autonomous selfing, which increased seed production in the study population.
Belgian Journal of Botany 08/2008; 141(1):3-13. · 0.63 Impact Factor
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Journal of Genetics 01/2006; 84(3):311-6. · 1.09 Impact Factor
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ABSTRACT: Plant pollination mode is not only related to floral morphology, but also responses to variation in the surrounding biotic and abiotic environments. A mature flower of Kosteletzkya virginica has a monadelphous androecium that bears 20–30 anthers and surrounds an exserted five-branched style with synstylous base. We observed sex dimorphism in K. virginica, androeciums being vestigial in female flowers. Stylar movements occurred if stigmas had not received pollen by insect pollinators, and stigmas could or could not contact with the anthers at the end of the anthersis day. Our observations and measurements indicated that pollination in K. virginica is achieved in two ways : insect-pollination and self-pollination by stylar movements. The latter includes direct stylar movements (stigmas contacted with the anthers at the end of the anthesis day) and a combination of stylar movements and corolla closure (stigma did not contact with the anthers at the end of the anthesis day), and there was a significant difference in style exsertion between the flowers whose stigmas contacted with the anthers at the end of the anthesis day and the flowers whose stigmas did not contact with the anthers. A field study demonstrated that ratios of flowers pollinated by stylar movements to insect-pollinated flowers were 0.154 and 0.162 in the studied population in 2002 and 2003, respectively. There was also a significant difference in this ratio between sunny and cloudy or rainy days.
Belgian Journal of Botany 06/2005; 138(1):39-46. · 0.63 Impact Factor
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ABSTRACT: To improve the productivity of Hippophae rhamnoides forest and to manage the forest reasonably, the community characteristics of Hippophae rhamnoides and the water and nutrient condition of the woodland were analyzed. The results showed that Hippophae rhamnoides grew fast and its adaptability was strong. 4-5 years old Hippophae rhamnoides could form shrubs-grass community. The biomass 1-8 years old Hippophae rhamnoides increased rapidly, but that of 8-11 years old increased more slowly. Hippophae rhamnoides older than 11 years could keep reasonable community structure and higher primary productivity by natural thinning. The utilization of soil moisture by Hippophae rhamnoides could be classified into four layers as faint utilization layer of root system (0-20 cm), utilization of root system (20-300 cm), adjustment layer supplied by soil moisture (300-400 cm), and faint adjustment layer (400-500 cm). Due to the soil improvement by Hippophae rhamnoides and the water retaining by litter, the soil moisture of 1-1.5 m layer could be easy to restore. Hippophae rhamnoides could keep the balance of nutrition in the woodland through the fixation of nitrogen by root nodule and the decomposition of litter. In the 6-9 years old Hippophae rhamnoides plantation, the total nitrogen content of soil might be improved from 0.05-0.1% to 0.2%.
Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban 10/2002; 13(9):1061-4.
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ABSTRACT: Kosteletzkya virginica (L.) Presl. is a perennial dicot halophytic species, that grows in brackish portions of coastal tidal marshes of the mid-Atlantic and southeastern United States. New saline mudflats have been increasing every year in Northern Jiangsu, China. In 1993, we introduced K. virginica (L.) into China from the Halophyte Biotechnology Center (University of Delaware, USA) as a potential species to improve the soil and develop ecologically sound saline agriculture. Our nearly 10 years of experimental research, both in a test garden and in the field, indicated that K. virginica adapts excellently to the heavy saline soils of Jiangsu Province, China. The average seed yield of K. virginica in 2001 at Yancheng was 638 kg/ha from 1-year old seedlings. There were significant variations among individuals from the unselected population of K. virginica on growth, quality, and seed yield traits. There is great potential to increase the seed yield if superior clones are selected. The seed yield of 35 selected individuals was six times greater than that of the average. Four growth traits of K. virginica were found to have a significant correlation with seed yield. However, there was no strong positive or negative correlation among seed quality traits. The mean seed weight and the germination ratio of the 35 selected individuals of K. virginica were 16.36±0.32 g and 76.11±1.82%, respectively. The percentage content of oil and crude protein in the seeds was 11.28±0.67 and 8.17±0.19%, respectively. The percentage of seed vigor of the selected individuals was 99%, as determined by soft X-ray radiography.
Ecological Engineering. 21:271-276.
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ABSTRACT: Sea buckthorn (Hippophae rhamnoides) is important environmentally and as a new commercial berry crop. Fourteen cultivars of sea buckthorn from China, Russia and Mongolia were evaluated for genetic relationships using RAPD data. Nine random primers were used to generate 114 RAPD markers by PCR. Among them, 103 (90.35%) were polymorphic. The genetic similarity ranged from 0.45 to 0.80 with a mean of 0.67. Genetic distance ranged from 0.23 to 0.80 with a mean of 0.40. Cluster analysis identified Zhongguoshaji from China (H. r. subsp. sienses) as the most genetically distinct cultivar. Hongguo (H. r. subsp. sienses), Zhongguoyou (H. r. subsp. sienses), the hybrid Liaohuerhao from China, Zeliang and Huoguang from Russia (H. r. subsp. mongolica) were clustered more distantly. The seven cultivars from Russia and Mongolia (H. r. subsp. mongolica) and the hybrid Liaohuyihao from China were grouped into two main clusters. Cluster I contained Chengsi, Liaohuyihao, Xiangyang, Chuyi and Wulangemu. Cluster II consists of Nuyou, Hongyun and Aleiyi. Data provide a scientific basis for selection and management of germplasm collections and crossing strategies for sea buckthorn.
Scientia Horticulturae.
