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71.
Arabinoxylans (AX), xylanase, and xylanase inhibitors have an important role in many cereal food processing applications. The effects of genotype, growing location, and their interaction (G × L) on AX, apparent xylanase activity, and apparent xylanase inhibition activity of Triticum aestivum xylanase inhibitor (TAXI) and xylanase inhibiting protein (XIP) were investigated for six hard red and six hard white spring wheat genotypes grown at three locations. Difference in total AX level among genotypes was not determined to a significant level by genotype. Instead, variability in total AX content was largely dependent on G × L. However, total AX content was significantly different between the two wheat classes. For bran xylanase activity, 25% of the variability could be attributed to G × L interaction. Moreover, there was significant difference between the bran xylanase activities in the two wheat classes. Bran TAXI activity and XIP activity were significantly different among genotypes. Genotype contributed 72% to the variability in TAXI activity and 39% in XIP. However, no significant difference was observed among the two wheat classes for TAXI or XIP activity. These results indicate that TAXI might be a stable parameter in segregating wheat genotypes with varying xylanase activity.  相似文献   
72.
Yields of large-seeded Andean (A) common bean (Phaseolus vulgaris L.) cultivars of Chile and Nueva Granada races are 40 to 60% lower compared to their Middle American (M) counterparts of small-seeded Mesoamerica and medium-seeded Durango races. Our objective was to use the concept of congruity backcrossing between Andean x Middle American inter-gene pool [AM 11833 = A 483 (A)///// A 686 (M) //// PVA 800A(A)/// ‘Carioca’ (M)// Carioca (M)/ G 19833 (A)] and between races within Andean gene pool [i.e., intra-gene pool Andean, AA 11834 = A483 (A)//// ‘Cardinal’(A) /// ‘Blanco Español’(A) // BlancoEspañol (A) / ‘Taylor’ (A)] to compare selection for seed yield improvement of large-seeded Andean beans. Seven hundred sixty seven F2-derived F3 (F2:3) families were produced for each population. Visual appraisal for total plant performance, combined with seed yield from non-replicated plots was used for selection of 551 families in F2:3, 182 families in F2:4, and 91 families in F2:5 in each population. Eight hundred twenty three F5:6 lines were developed from the 91 F2:5 families in each population. Visual selection, combined with seed yield in non-replicated plots was again used to select 294 lines in F5:6 in each population. Similarly, 44 highest yielding F5:7 lines were selected in AM 11833 and 39 F5:7 lines in AA 11834. Thus, single plant selections were made in the F2 and F5, and plants within each plot were harvested in bulk in F3, F4, F6, and F7. Thirty nine F5:8 lines from AA 11834 and 44 lines from AM 11833, parents, and checks were evaluated at Popayán and Quilichao, Colombia in 1998 and 1999. Selected lines in both populations, on average, out-yielded the mean of their large-seeded Andean parents. Mean yield of the lines selected from AM 11833 was 50% higher than AA 11834 lines. Twelve F5:8 lines out-yielded the highest yielding Andean parents G 19833 and A 483 in AM 11833, whereas only one line yielded significantly higher (p < 0.05) than the highest yielding parent A 483 in AA 11834. However, none of selected lines out-yielded small-seeded Middle American parents used in AM 11833 (A 686 and ‘Carioca’). The mean 100 seed-weight of AA 11834 was 36 g compared to 28 G for AM 11833 F5:8 lines. Selected lines had similar days to maturity as parents in AM 11833, and matured 3 d later in AA11834. Correlation coefficients between yield and 100 seed-weight were negative in both populations. Yield and days to maturity were positively correlated in AA 11834.  相似文献   
73.
Genetic diversity within and between the maintainer (B) and restorer (R) lines used in hybrid breeding programs of the Philippine was investigated with information from analysis of pedigree record, quantitative traits and SSR assays. Mean coefficients of coancestry were calculated as 0.11 within R lines, 0.27 within B lines, and 0.04 between R and B lines, indicating greater diversity among R lines than among B lines, and the significant divergence between B and R lines. These results are consistent with those obtained from quantitative trait analysis and SSR marker assays. Relative gene diversity for 37 random SSR markers averaged 0.20 within B lines,0.28 within R lines, and 0.52 between two groups of lines. There were no consistent associations among various genetic diversity measures. Random sets of SSR marker and pedigree based diversity measures had no significant correlation with mid-parent heterosis for grain yield and biomass, indicating that prediction of heterosis for complex traits based on these two genetic diversity estimates is difficult. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
74.
ABSTRACT Information and Communication Technology (ICT) has become an important tool to promote a variety of public goals and policies. In the past years much attention has been given to the expected social benefits from deploying ICTs in different urban fields (transportation, education, public participation in planning, etc.) and to its potential to mitigate various current or emerging urban problems. The growing importance of ICTs in daily life, business activities, and governance prompts the need to consider ICTs more explicitly in urban policies. Alongside the expectation that the private sector will play a major role in the ICT field, the expected benefits from ICTs also encourage urban authorities to formulate proper public ICT policies. Against this background, various intriguing research questions arise. What are the urban policy‐makers’ expectations about ICTs? And how do they assess the future implications of ICTs for their city? A thorough analysis of these questions will provide a better understanding of the extent to which urban authorities are willing to invest in and to adopt a dedicated ICT policy. This study is focusing on the way urban decision‐makers perceive the opportunities of ICT policy. After a sketch of recent development and policy issues, a conceptual model is developed to map out the driving forces of urban ICT policies in cities in Europe. Next, by highlighting the importance of understanding the decision‐maker's “black box,” three crucial variables are identified within this box. In the remaining part of the paper these three variables will be operationalized by using a large survey comprising more than 200 European cities. By means of statistical multivariate methods (i.e., factor and cluster analysis), the decision‐makers were able to be characterized according to the way they perceive their city (the concept of “imaginable city”), their opinion about ICT, and the way they assess the relevance of ICT policies to their city. Next, a solid explanatory framework will be offered by using a log‐linear logit analysis to test the relationships between these three aspects.  相似文献   
75.
Quinoa is recently introduced to Pakistan as a salt‐tolerant crop of high nutritional value. Open field trials were conducted to evaluate its performance on normal and salinity/sodicity‐degraded lands at two locations of different salinity/sodicity levels, S1 (UAF Farm, Normal Soil), S2 (Paroka Farm UAF, saline sodic), S3 (SSRI Farm, normal) and S4 (SSRI Farm, saline sodic) during 2013–2014. Two genotypes (Q‐2 and Q‐7) were grown in lines and were allowed to grow till maturity under RCBD split‐plot arrangement. Maximum seed yield (3,062 kg/ha) was achieved by Q‐7 at normal field (S1) soil which was statistically similar with yield of same genotype obtained from salt‐affected field S2 (2,870 kg/ha). Furthermore, low yield was seen from both genotypes from both S3 and S4 as compared to S1 and S2. Q‐7 was best under all four conditions. Minimum yield was recorded from Q‐2 (1,587 kg/ha) at S4. Q‐7 had higher SOD, proline, phenolic and K+ contents, and lower Na+ content in leaves as compared to Q‐2. High levels of antioxidants and K+/Na+ of Q‐7 helped to withstand salt stress and might be the cause of higher yields under both normal and salt‐affected soils. Seed quality (mineral and protein) did not decrease considerably under salt‐affected soils even improved seed K+, Mg2+ and Mn2+.  相似文献   
76.
Even in the temperate climates of Europe, increasing early season drought and rising air temperature are presenting new challenges to farmers and wheat breeders. Sixteen winter wheat (Triticum aestivum L.) genotypes consisting of three hybrids, six line cultivars and two breeding lines from Germany as well as five line cultivars from France, Austria, Slovakia, Hungary and the Ukraine (referred to as “exotic” lines) have been included in this study. The genetic materials were evaluated over three growing seasons under a range of soil moisture regimes at the three North German sites Braunschweig (irrigated and drought‐stressed), Warmse (rainfed) and Söllingen (rainfed). The average grain yields in the twelve growth environments (water regime × season combinations) ranged from 6.1 to 13.5 t ha?1. The exotic lines showed little evidence of specific phenological adaptation to drought although they are frequently faced with water scarcity in their countries of origin. The hybrids and German lines exhibited higher regression coefficients (bi) to environmental means than the exotic lines, indicating particular adaptation to favourable growing conditions. The phenotypical correlations of grain yield between the various environments were high, ranging for instance from 0.6 to 0.8 for the irrigated and drought‐stressed environments at Braunschweig. It is thus expected that in the foreseeable future continued selection aiming at high yield potential will suffice as a means to counter the expected increase in droughts.  相似文献   
77.
78.
Direct seeding is increasingly being practiced in rice cultivation areas because it saves labour and reduces cost of production and management. In this study, four japonica‐type breeding lines were developed from a cross of a japonica cultivar and an AG‐tolerant donor, KHO, using marker‐assisted selection. Validation of the target genes AG1 and AG2 in the selected lines was examined by PCR analysis and the background recovery rate by the recurrent parent was confirmed by genotyping using a 6K SNP chip. Compared to the recurrent, the survival rates of the selected lines were improved in a range from 33% to 115% in three conditions; in particular, the survival rate was increased in more than twice that of the recurrent parent under the hypoxic condition. The main agronomic trait, yield and quality‐related traits were similar to those of the recurrent parent. The use of these lines will contribute to the expansion of the cultivation area due to the proven economic benefits of direct seeding in Korea.  相似文献   
79.
The aim of this paper is to evaluate the role that agglomeration may have on vertical boundaries in exchanges associated with high transaction costs. Transaction cost economics identifies the presence of specific assets in stages of the value chain as the main driver of vertical integration. However, under the trustworthy and shared social milieu that agglomerated spaces may confer, neighboring firms can enjoy lower opportunism risk and communication costs. Therefore, we assume that even in the presence of specific assets, physically proximate firms are more likely to remain specialized and establish market exchanges. Empirical evidence in 10,186 establishments from the Spanish meat industry confirms these hypotheses, although it is found that the moderating role of agglomeration in the relationship between asset specificity and vertical integration has a limited geographical reach.  相似文献   
80.
The purpose of this study was to investigate how Taiwanese high‐tech firms' foreign direct investment (FDI) leads to agglomeration and competition among cities in China. By using social network analysis to analyze 1,111 subsidiaries affiliated with 270 multinational corporations (MNCs) during the years between 1988 and 2006 in 30 major Chinese cities, this study finds that: 1) agglomeration in Chinese cities falls into three primary categories: the hub cluster, the communication‐extended cluster, and the computer‐extended cluster. Among the aforementioned clusters, the hub cluster is the most critical in terms of firm location, and therefore is often a high‐priority investment site for Taiwanese high‐tech firms. 2) Chinese cities fall into four primary groups, or “blocks”: the core block, the coast block, the inland block, and the periphery block; these groups were determined by applying a structural equivalence analysis of which members of each type are in competition with one another. By linking the findings of the urban network characteristics to Chinese regional economic policies, this study provides guidance to aid executives in determining the optimal location for future FDI. Implications and suggestions for host country governments in terms of firms' investment strategies are also discussed.  相似文献   
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