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Improvement in grain yield is an important objective in high-oil maize breeding. In this study, one high-oil maize inbred was crossed with two normal maize inbreds to produce two connected recombinant inbred line (RIL) populations with 282 and 263 F 7:8 families, respectively. The field experiments were conducted under four environments, and eight grain yield components and grain oil content were evaluated. Two genetic linkage maps were constructed using 216 and 208 polymorphic SSR markers. Quantitative trait loci (QTL) were detected for all traits under each environment and in combined analysis. Meta-analysis was used to integrate genetic maps and detected QTL in both populations. A total of 199 QTL were detected, 122 in population 1 and 87 in population 2. Seven, 11 and 19 QTL showed consistency across five environments, across two RIL populations and with respective F 2:3 generations, respectively. 183 QTL were integrated in 28 meta-QTL (mQTL). QTL with contributions over 15% were consistently detected in 3-4 cases and integrated in mQTL. Each mQTL included 3-19 QTL related to 1-4 traits, reflecting remarkable QTL co-location for grain yield components and oil content. Further research and marker-assisted selection (MAS) should be concentrated on 37 consistent QTL and four genetic regions of mQTL with more than 10 QTL at bins 3.04-3.05, 7.02, 8.04-8.05 and 9.04-9.05. Near-isogenic lines for 100-grain-weight QTL at bin 7.02-7.03, for ear-length QTL at bin 7.02-7.03 and for rows-per-ear QTL at bin 3.08 are now in construction using MAS. Co-located candidate genes could facilitate the identification of candidate genes for grain yield in maize. © 2011 Springer Science+Business Media B.V. Source

Cai C.,Northwest University, China | Li X.,Ningxia Academy of Agricultural science | Ma H.,Northwest University, China | Ren X.,Northwest University, China | And 2 more authors.
Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery | Year: 2013

Bioimpedance properties of Fuji apple fruit with different freshness were investigated. Fruit with weight loss of 0, 5%, 10%, 15% and core-browning under room temperature were chosen as samples corresponding to descending freshness grades of 1, 2, 3, 4, 5, respectively. 126 observations of 14 bio-impedance parameters under nine frequencies of total 424 fruit from each grade were measured fruit by fruit with LCR impedance meter. Data were computed by using the sparse principal component analysis-linear classifier (SPCA-LDC) model. Results indicated that classification accuracy reached to maximum stably when the ratio of training sample to test sample of 9:1 and former 39-45 principal component (PC) were adopted. The least 39 PCs were consisted of 44 from the 126 observations. Average rate of classification accuracy reached to 87.90% within 50 test repeats. Source

Sun J.-C.,Northwest University, China | Sun J.-C.,Chinese Academy of Agricultural Sciences | Sun J.-C.,Ningxia Academy of Agricultural science | Cao G.-L.,Chinese Academy of Agricultural Sciences | And 3 more authors.
Genetic Resources and Crop Evolution | Year: 2012

The genetic structure and diversity of eight pairs of rice landraces from in situ (collected in 2007) and ex situ (collected in 1980) conservation programs were studied using 20 pairs of microsatellite markers with high polymorphism. Each pair of rice landraces shares a name and origin and has similar seed and plant traits. The number of alleles detected in the populations from in situ conservation ranged from 43 to 88 with the mean number of alleles per locus ranging from 2.15 to 4.40, while the number of alleles detected in the populations from ex situ conservation ranged from 33 to 65, and the mean of alleles per locus ranged from 1.65 to 3.25. Compared to the ex situ populations, the number of alleles, the number of specific alleles and the genetic diversity index showed a significant increase in the in situ populations. Further, the numbers of specific alleles from in situ populations were 2.1-5.0 times greater than in ex situ populations except for rice landrace 'Qitougu'. An AMOVA showed that the within-landrace genetic structure differed significantly between in situ and ex situ conservation treatments with differences exceeding 20%. The analysis of genetic similarity reached similar conclusions to those of the AMOVA. Compared with ex situ conservation programs, the rice landraces under in situ conservation programs had more alleles and higher genetic diversity in Yunnan of China. © 2012 Springer Science+Business Media B.V. Source

Zhang S.,Northwest University, China | Zhang S.,Chinese Academy of Agricultural Sciences | Zhang S.,Ningxia Academy of Agricultural science | Xu Z.-S.,Chinese Academy of Agricultural Sciences | And 7 more authors.
Plant Molecular Biology Reporter | Year: 2013

Heat shock factors (HSFs) in plants regulate heat stress response by mediating expression of a set of heat shock protein (HSP) genes. In the present study, we isolated a novel heat shock gene, TaHSF3, encoding a protein of 315 amino acids in wheat. Phylogenetic analysis showed that TaHSF3 belonged to HSF class B2. Subcellular localization analysis indicated that TaHSF3 localized in nuclei. TaHSF3 was highly expressed in wheat spikes and showed intermediate expression levels in roots, stems, and leaves under normal conditions. It was highly upregulated in wheat seedlings by heat and cold and to a lesser extent by drought and NaCl and ABA treatments. Overexpression of TaHSF3 in Arabidopsis enhanced tolerance to extreme temperatures. Frequency of survival of three TaHSF3 transgenic Arabidopsis lines was 75-91 % after heat treatment and 85-95 % after freezing treatment compared to 25 and 10 %, respectively, in wild-type plants (WT). Leaf chlorophyll contents of the transformants were higher (0.52-0.67 mg/g) than WT (0.35 mg/g) after heat treatment, and the relative electrical conductivities of the transformants after freezing treatment were lower (from 17.56 to 18.6 %) than those of WT (37.5 %). The TaHSF3 gene from wheat therefore confers tolerance to extreme temperatures in transgenic Arabidopsis by activating HSPs, such as HSP70. © 2012 Springer Science+Business Media New York. Source

Zhu M.-M.,Ningxia Academy of Agricultural science | Cai F.-H.,Ningxia Entry Exit Inspection and Quarantine Bureau | Zhang R.,Ningxia Academy of Agricultural science | Zhang Y.,Ningxia Academy of Agricultural science | And 4 more authors.
Chinese Journal of Applied Ecology | Year: 2010

Based on geographic information system (GIS) and geostatistical analysis, this paper studied the spatial structure of Aphis gossipii Glover population in Xiangshan District of Zhongwei City, Ningxia Province, with the spatial distribution of the population simulated by ordinary Kriging interpretation. The spatial structure of A. gossipii population varied with its occurrence stage (initial, blossom, and final stage). The semivariograms of A. gossipii could be described by exponential or Gaussian model, indicating that A. gossipii had an aggregated spatial arrangement. The aggregation degrees at different occurrence stages were all beyond 45%, and the spatial correlation ranged from 10.37 km to 29.11 km. The spatial variance was greatly affected by spatial autocorrelation. The population dynamics of A. gossipii at its different occurrence stages could be easily analyzed and intuitively simulated from the two aspects of time and space by spatial distribution simulation, and thus, the occurrence position and degree of A. gossipii could be easily determined. Source

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