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Lanzhou Alkaline Stretched Noodles (LASN) has introduced by Meng et al. in previous research paper (2007). In order to discover the LASN specialty wheat quality requirement for allelic variations at Glu-1 of northwest China spring wheats, 2 northwest China spring wheat cultivars and 39 elite F6 breeding lines were adopted to determine the high-molecular-weight glutenin subunits (HMW-GS) composition by one step one-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) based on the protocol of Singh et al. (1991). The results showed that the wheat quality and LASN quality were characterised by Glu-1 alleles significantly. Glu-A1 /1 correlated to high protein content and better extensibility (L) than other allelic variations. Glu-A1 /1, Glu-B1 /17+18 and Glu-D1 /5+10 were beneficial to dough strength (W), meanwhile Glu-A1 /2* and Glu-D1 /5+10 were good to dough tenacity (P). Glu-D1 /5+10 strongly correlated to high volume of SDS-sediment significantly. Allelic variations at Glu-A1 / (1, 2*), Glu-B1 /17+18 and Glu-D1 /5+10 were beneficial alleles for wheat quality as well as LASN quality. However, Glu-A1 /null and Glu-D1 /2+12 were inferior alleles for wheat quality and LASN quality.

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Small-scale vegetation patterns are frequently the results of plant-plant interactions such as facilitation and competition. Facilitation should be particularly pronounced when both abiotic and biotic stresses are high, but few studies were conducted in such habitats. In heavily-grazed pastures on the eastern Tibetan Plateau, an area with both high abiotic stress and strong biotic disturbance, we made relevés of herb species both beneath and outside canopies of three shrub species (Spiraea alpina, Sibiraea angustata and Potentilla fruticosa) differing in palatability and canopy structure. Herb species richness (S), pooled cover (PC) of all species, number of flowering species (FS) and number of inflorescences of all species (IN) were greater outside than beneath the shrub canopies. Evenness (J), in contrast, was smaller outside, while Shannon’s diversity index (H) was the same. Differences in S and J between plots beneath and outside the shrub canopies were greater in the case of P. fruticosa than in the cases of S. angustata and S. alpina, but differences in PC, FS or IN did not depend on the shrub species. Among the common species (frequency ≥6), 47–85% were equally frequent beneath and outside the shrubs, 13–39% were more frequent outside and 3–13% were more frequent beneath the shrubs. For the rarest species (frequency < 6), however, more species occurred beneath than outside the shrubs. The ordination diagram showed a clear separation between the relevés outside and beneath the shrubs and a gradient from P. fruticosa via S. alpina to S. angustata, accompanied by a distinct decrease in the extent of the difference between the vegetation beneath and outside the shrub canopies. In conclusion, the three shrub species facilitated some species in the herb layer and each shrub species had a specific impact, related to its canopy structure and palatability but also to the grazing pressure, which was greater around the P. fruticosa shrubs than around S. alpina and S. angustata.

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Uniformity in the height of main stem and tillers is a key factor affecting ideal plant type, a key component in super high-yielding rice breeding. An understanding of the genetic basis of the panicle layer uniformity may thus contribute to breeding varieties with good plant type and high yield. In the present study, a doubled haploid (DH) population, derived from a cross between indica rice variety Zhai-Ye-Qing 8 (ZYQ8) and japonica rice variety Jing-Xi 17 (JX17) was used to analyze quantitative trait loci (QTL) for panicle layer uniformity related traits. Six, four and three QTL were detected for the highest panicle height (HPH), lowest panicle height (LPH) and panicle layer dis-uniformity (PLD), respectively. qHPH-1-1 and qPLD-1 were located at the same interval on chromosome 1. The JX17 allele(s) of these QTL increased HPH and PLD by 2.57 and 1.26 cm, respectively. Similarly, qPLD-7 and qHPH-7 were located at the same interval on chromosome 7, where the ZYQ8 allele(s) increased HPH and PLD by 3.74 and 1.96 cm, respectively. These four QTL were unfavourable for panicle layer uniformity improvement because a decrease of the PLD was accompanied by decrease of the plant height. qPLD-6 and qLPH-6-1 were located at the same interval on chromosome 6, however here the JX17 allele(s) increased LPH, but decreased PLD, suggesting that this QTL was favourable for improvement of panicle layer uniformity. The markers identified in this study are potential for marker assisted breeding for the improvement of the panicle layer uniformity and ideal plant type.

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