Biomedical subjects

Wenxiong Lin

Publications and source records attributed to Wenxiong Lin.

25 records · Page 2Linked to original sources

PubMed2003

[Molecular ecological basis of high-yielding formation of rice and its application].

This paper introduced the developmental genetics and its molecular ecological basis of high yielding formation of rice in the past decade, and analyzed the advantage and the shortage of comparative physiological approach traditionally used in the research work on crop cultivation. It was emphasized to actively introduce the research contents and its methodology from relative disciplines to deeply understand the scientific issue, and suggested that the key to realize stable and high yielding of rice was to develop a rational cultivation system based on the properties of genetic effects on the traits in different developmental stages by controlling and regulating the traits governed by dominant effect genes and additive effect genes x environment in same direction, which was considered as the main characteristics and the technological innovation of modern crop genetic ecological cultivation science. Finally, the development trend of crop cultivation science shifting to molecular crop cultivation science was predicted and discussed.

Carbohydrates↗

PubMed2002

[Induction of sesquiterpene cyclase gene expression and antioxidant enzymes regulated by exongenous salicylic acid in leaves of Capsicum annuum].

An analysis of the induction of sesquitèrpene cyclase gene expression and antioxidant enzymes in Capsicum annuum by exongenous salicyclic acid (SA) pointed out that the sesquiterpene cyclase gene expression in detached pepper leaves was induced by 0.5-4 mmol.L-1 of exongenous SA, whereas the enzyme activity and accumulation of cyclase mRNA were much lower, and it took a longer time (36 h) for the gene to be induced to express after SA treatment, comparing to other elicitors such as UV and fungi treatment. The activities of SOD and POD were enhanced, while the CAT activity was inhibited to some degree. Consequently, H2O2 content was increased in SA treated pepper leaves. H2O2 accumulation was related to the integrated influences from antioxidant enzymes.

Capsicum↗

PubMed2002

[Effect of enhanced UV-B radiation on polyamine metabolism and endogenous hormone contents in rice (Oryza sativa L.)].

The results showed that the activities of Agrinine decarboxylase(ADC), Ornithine decarboxylase(ODC) and s-Adenosylmethionine decarboxylase(SAMDC) were increased by 165.74%, 104.60% and 89.60% in the leaves of Shan You63(Sy63) and by 59.91%, 41.30% and 23.68% in the leaves of Nancheum(NC). Only ADC and ODC activities were increase by 115.93%, 14.45%, but SAMDC activity was decreased by 33.01% in the leaves of IR65600-85 respectively in the exposure to enhanced UV-B radiation for 7-14 days. In late treatment time course(21-28 d), the activities of ADC and ODC were increased by 89.72% and 3.71% in the leaves of Sy63 exposed to UV-B radiation for 21-28 days and by 73.95% and 27.38% in the leaves of NC. The activity of ADC was also increased by 94.41%, but ODC activity was decreased by 13.57% in the leaves of IR65600-85 compared with the controls. As far as SAMDC was concerned, the enzymic activities in the leaves of Sy63, NC and IR65600-85 were reduced by 40.06%, 19.20% and 38.21% respectively in the exposure to enhanced UV-B radiation for 21-28 days. The reverse was true in the case of Polyamine Oxidase (PAO), this in turn resulted in increased contents of Polyamine(PA) especially putrescine(Put). In addition, the result also indicated that the contents of IAA and GA1/3 were significantly reduced in all rice cultivars used for this experiments with enhanced UV-B radiation treatments for 7-28 days, in which the contents of IAA and GA1/3 were decreased by 58.92% and 45.48% in the leaves of Sy63, by 43.31% and 56.20% in the leaves of NC, and by 38.60% and 47.33% in the leaves of IR65600-85. The contents of ZRs in the leaves of the three cultivars concerned were lower in earlier treatment time courses (7-14 d), but much higher in late courses(21-28 d) compared with the their counterparts. With regard to the endogenous hormone of ABA, the content was significantly increased by 14.4%, 99.6% and 56.7% respectively in the three rice cultivars concerned exposed to enhanced UV-B radiation for 7-28 days, thereby led to decreased values of IAA/ABA, GA1/3/ABA and ZRs/ABA, consequently suppressed growth and development of rice.

Adenosylmethionine Decarboxylase↗

PubMed2002

[Effects of enhanced ultraviolet-B radiation on growth development and yield formation in rice (Oryza sativa L.)].

Effect of enhanced ultraviolet-B radiation (280-320 nm) on growth, development and yield formation in the three rice cultivars (Oryza sativa L.) under pot conditions were investigated. The results showed that enhanced ultraviolet-B radiation decreased rice height, tiller number, total leaf area and biomass, but the inhibitory rate varied in different cultivars and developmental stages. Plant height was decreased by 9.4%-12.2% in seedling stage, plant shoot and root of dry matter were decreased by 45.3%-59.8% and 54.9%-59.0% respectively in tillering period. The leaf emergence delayed, resulting in delayed time of flowering in Shanyou 63, Nanchuan and IR65600-85 by 2d, 3d and 7d, prolonged total growth period by 3d, 4d and 9d. Net photosynthesis rate of Shanyou 63, Nanchuan and IR65600-85 were decreased by 11.9%, 12.8% and 29.7%, respectively. Attributed to decreased contents of chlorophyll a, b, carotenoid and induction kinetics parameters of Fv, Fv/Fm and Fv/Fo. Effective panicle per plant, total grain number per panicle, filled grain rate and 1000-grain weight were decreased by enhanced UV-B radiation. Consequently the grain yields were reduced by 25.2%-31.1%.

Biomass↗

PubMed2002

[Developmental genetic analysis of panicle dry weight of indica hybrid rice oryza sativa under different environmental conditions].

Four indica sterile lines (A) and corresponding maintainer lines (B) as well as five indica restorer lines, which varied in panicle dry weight, were used to create genetic populations of two generations according to incomplete diallel cross design (4 x 5). Analysis on panicle dry weight at different developmental stages based on tow-years experimental data was conducted by using additive-dominant developmental genetic models with genotype effects and genotype x environment interaction effects. The results showed that panicle dry weight was controlled by both genetic main effects and genotype x environment interaction effects in the whole developmental process. During the early-middle developmental periods (15 days after flowering), panicle dry weight was mainly governed by dominant effects, and dominant genes expressed with large amount. The meanwhile, positive effects produced by environmental factors appeared to be significant. Proper cultivation measure to create good external environment conditions for rice panicle was helpful to promote the expression of heterosis potential completely. Within the middle-late developmental periods (from the fifteenth day to the thirtieth days after flowering), additive effects played major role, and its genes expresed in the most active state. Genetic selection for panicle conducted in this period was expected to gain better genetic advancement.

Crops, Agricultural↗

PubMed2002

[Genetic ecology of rice allelopathy on receiver plant].

In this study, 5 parental rice lines with different allelopathic potential were employed in partial diallel cross (4 x 5) to get 10 groups of F1 seeds. After testing the inhibitory effects of 5 parents and 10 F1s under different environment at different leaf stage on the shoot length of receiver plant lettuce(Lactuca sativa L.), dynamic genetics of rice allelopathy and its genotype x environment effects were analyzed by using additive-dominant developmental genetic models. The results showed that additive and dominant effect genes expressed alternatively during 3-leaf stage to 8-leaf stage in rice seedling. As additive effect genes were pronounced at 7-leaf stage, dominant effect genes appeared to play the most important role at 3-leaf stage and 6-leaf stage but the two effect genes were equally important at 5-leaf stage and 8-leaf stage. Heritabilities analysis indicated that the general heritability in the narrow sense(HN2) was significant at 5-, 7- and 8-leaf stage, and decreased with increasing leaf stage. Rice allelopathy was significantly affected by genotype x environment (GE) interaction, suggesting that the environment of allelopathic rice development must be controlled for practical use.

Ecology↗

PubMed2002

[Screening methodology for rice (Oryza sativa) genotypes with high phosphorus use efficiency at their seedling stage].

Under hydroponic culture, the responses of rice (Oryza sativa) genotypes to low P stress were respectively evaluated by means of relatively-higher P concentration in a controlled system with insoluble phosphate source (Ca3 (PO4)2) and of relatively-lower concentration with 0.5 mg P/L in which NaH2PO4 was the soluble phosphate. Relative indices such as relative dry weight of tillers (RTW), total relative plant dry weight (RPW), relative number of tillers (RTN), relative dry weight of root (RRW), relative dry weight of shoot (RSW), relative leaf age (RLA) and relative plant height (RPH) were used to screen as the tolerant indices to P deficiency, and the correlations among screening criteria per se were analyzed. The results showed that there were significant differences of tolerant indices to P deficiency in the test rice genotypes. When the rice cultivars were exposed to low P stress with the relatively-higher P concentration to be screened, the relative tiller dry weight (RTW), relative shoot dry weight (RSW) and total relative plant dry weight (RPW) could be used as the better screening criteria, especially RTW was considered as a sensitive and reliable screening criterion because its coefficient of variation (CV) and the variable range of data among the test varieties should be large. However, when rice genotypes were grown in the stress condition with relatively-lower P concentration, the screening criteria were different, and it suggested that relative shoot dry weight (RSW) or total relative plant dry weight (RPW) was the best single screening criterion.

Genotype↗