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61.
本文采用半姊妹与全姊妹轮回选择方法对玉米“沈综”群体实施了三轮次改良。结果表明,两种改良方案对“沈综”群体改良皆有显著效果,半姊妹方案取得产量每轮遗传增益为12.91%,明显大于全姊妹方案对农艺性状所取得的遗传进度也较大。三轮选择后,群体大多数农艺性状的遗传变异度没有下降。半姊妹方案实施过程中,更换测验种可扩大对被改良群体不同基因位点的选择压力。 相似文献
62.
戊二醛和季铵盐复合物对黄鳝的急性毒性作用 总被引:1,自引:0,他引:1
研究了戊二醛和季铵盐复合物对黄鳝(Monopterusalbus)的急性毒性作用,观察了黄鳝对2种药剂的毒性反应症状,得出了戊二醛对黄鳝的24h、48h、72h、96h的半致死浓度(LC50)分别为58.77、41.69、38.54、30.05mL/m3,季铵盐复合物对黄鳝的24h、48h、72h、96h的LC50分别为296.72、164.10、111.55、76.76mL/m3;2种药物对黄鳝的安全浓度分别为3.01mL/m3和7.68mL/m3;2种药物对黄鳝的毒性强弱顺序为:戊二醛>季铵盐复合物。 相似文献
63.
Limeng Zhang Runting Li Longxin Chen Zhenzhen Xing Yue Song Xiaoning Nie Linqing Wang Hongye Han Aiju Liu Xiaofei Ma Runlin Z. Ma Shujun Tian 《Reproduction in domestic animals》2020,55(6):737-746
Previous studies have shown that four and a half LIM domain protein 2 (FHL2) plays an essential role in the regulation of follicular development in mammals. Although the FHL2 genes of human and mouse have been well characterized, the expression and location of FHL2 in ovary and the biological functions of FHL2 on granulosa cells (GCs) of ovine are still not clear. In this study, full-length complementary DNA (cDNA) of FHL2 from ovine follicular GCs was amplified by real-time PCR (RT-PCR). The expression and location of FHL2 in ovary and GCs of ovine were studied by immunohistochemistry and immunofluorescence, and the biological effects of FHL2 on the cell proliferation, cell apoptosis, cell cycles and expression level of related genes of ovine GCs were also explored by overexpression or knockdown of FHL2. The results indicated that FHL2 was expressed in ovine follicular GCs and the sequence of the FHL2 cDNA was consistent with that predicted in GenBank, which did not cause an amino acid change. According to the results, FHL2 was expressed in ovine ovary and mainly located in the cytoplasm and nucleus of GCs. In addition, overexpression of FHL2 significantly reduced the cell viability, promoted the cell apoptosis and decreased the percentage of G0/G1 and S phase cells. RT-PCR showed that overexpression of FHL2 significantly increased the mRNA expression level of Bax and decreased the expression of Bcl-2 and the Bcl-2/Bax mRNA ratio compared with the control group. Besides, the knockdown of FHL2 gene in ovine GCs significantly improved the cell viability, suppressed the cell apoptosis, decreased the mRNA expression level of Caspase-3 gene, increased the Bcl-2/Bax mRNA ratio and increased the percentage of S and G2/M phase cells. Our results suggest that FHL2 may play an important role in the biological functions of GCs in ovine. 相似文献
64.
For a better understanding of the inheritance of seed yield traits in Quinoa (Chenopodium quinoa) Willd., a half-diallelic crossing experiment with six diverse but uniform breeding lines was conducted. True hybrid plants
were detected by means of differences in panicle colour in 14 out of the 15 crosses performed. The agronomic performance of
14 F2 populations and six parental lines was evaluated in field trials on fertile clay soil. General and specific combining ability
of the lines (GCA and SCA) were estimated. Highly significant differences in GCA effects were found between the lines for
plant height at maturity, early flowering, early maturity, seed yield and thousand seed weight. Significant SCA effects were
only found for plant height at maturity. However, SCA effects were rather small and accounted for 7% of the total variance.
The finding of large GCA effects and low SCA effects suggests that best selection results could be expected from crosses between
the agronomic best performing genotypes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
65.
根据六缸柴油机及双进口无叶涡轮增压器的特点,建立了工作过程数学模型;提出了半涡轮叶轮计算法,使双进口无叶涡轮增压器,可以像单进口无叶涡轮增压器一样进行模拟计算,从而解决了双进口无叶涡轮增压器的六缸柴油机工作过程模拟计算的理论问题。 相似文献
66.
67.
小麦新品种鄂恩4号种子愈伤组织的诱导 总被引:1,自引:0,他引:1
选取小麦新品种鄂恩4号成熟胚和带胚半粒种子为外植体,采用MS基本培养基,以6种浓度的植物生长素2,4-D和2种浓度的细胞分裂素6-BA配伍,组成12种不同浓度组合的培养基,研究了3种预处理种子、激素浓度及外植体对愈伤组织诱导的影响。结果表明,MS 2,4-D2~8mg·L-1均能有效地诱导愈伤组织,2,4-D浓度达到10mg·L-1时,对愈伤组织的形成起一定的抑制作用;带胚的半粒种子出愈率低于成熟胚;常温处理的种子其愈伤组织的诱导率比低温、CaCl2处理的种子出愈率高。 相似文献
68.
69.
以2个推广品种两优培九、T优207和2个新组合M175s/胜泰1号、M1s/9311等4个杂交稻品种(组合)为试验材料,在大田条件下进行了半期旱作(插秧至分蘖盛期保留水层而分蘖后期至成熟期旱作)栽培试验.结果表明:与常规水作比较,半期旱作节省后期灌溉用水16.79%;除T优207产量略低于对照外,其它3个品种的产量均略高于对照,但增减产均未达到显著水平;除两优培九的千粒重显著下降外,其它产量性状与对照无显著差异.米质分析结果表明,半期旱作可以降低稻米垩白粒率,提高蛋白质含量,除T优207外,其它品种的精米率及整精米率均有所提高. 相似文献
70.
Oulkar DP Banerjee K Patil SH Upadhyay AK Taware PB Deshmukh MB Adsule PG 《Pest management science》2009,65(2):183-188
BACKGROUND: This work was undertaken to determine the preharvest interval (PHI) of buprofezin to minimize its residues in grapes and thereby ensure consumer safety and avoid possible non‐compliance in terms of residue violations in export markets. Furthermore, the residue dynamics in three grapevine soils of India was explored to assess its environmental safety. RESULTS: Residues dissipated following non‐linear two‐compartment first + first‐order kinetics. In grapes, the PHI was 31 days at both treatments (312.5 and 625 g a.i. ha?1), with the residues below the maximum permissible intake even 1 h after foliar spraying. Random sampling of 5 kg comprising small bunchlets (8–10 berries) collected from a 1 ha area gave satisfactory homogeneity and representation of the population. A survey on the samples harvested after the PHI from supervised vineyards that received treatment at the recommended dose showed residues below the maximum residue limit (MRL) of 0.02 mg kg?1 applicable for the European Union. In soil, the degradation rate was fastest in clay soil, followed by sandy loam and silty clay, with a half‐life within 16 days in all the soils. CONCLUSION: The recommendation of the PHI proved to be effective in minimizing buprofezin residues in grapes. Thus, this work is of high practical significance to the domestic and export grape industry of India to ensure safety compliance in respect of buprofezin residues, keeping in view the requirements of international trade. Copyright © 2008 Society of Chemical Industry 相似文献