耐草甘膦大豆种质资源筛选的研究

通过田间试验结合室内生物测定的方法,对不同大豆品种(系)进行了耐草甘膦特性的筛选,以期获得耐草甘膦大豆育种的新种质资源。结果表明,在草甘膦常规剂量下,不同大豆品种(系)对草甘膦耐性程度有着较大差异。褐皮豆和绥无腥豆1号耐性程度较强;DS系列大豆对草甘膦的耐性明显高于其他品系。通过室内生物测定对耐性程度较高的品种(系)进行进一步研究发现,DS品系等4个品系的耐性程度较高,其耐性倍数分别为4.23、3.82、2.93、2.59和2.48。室内考种数据表明,草甘膦虽然对耐性品系的株高有不同程度的抑制;但耐性品系可以正常的成熟结实,在单株荚数、百粒重等重要指标上具有可利用价值。

耐草甘膦水稻种质资源的创制和鉴定

为培育耐草甘膦的水稻新品种,减少化学除草剂的使用,降低农药对环境的危害并提高水稻产量,本研究通过田间试验结合实验室鉴定的方法,对84份来自辐照+EMS诱变后再杂交选育而成的水稻材料进行耐草甘膦特性筛选鉴定。结果表明,水稻材料在三叶期喷1 mg·m L^(-1)草甘膦时都能存活,无明显药害症状,药害级别为1~2级;在草甘膦浓度为2 mg·m L^(-1)和3 mg·m L^(-1)时,这些材料对草甘膦的耐性程度有较大差异,其中CA11和CA21的存活率较高,为83.3%;草甘膦浓度为4mg·m L^(-1)和5mg·m L^(-1)时,植株大部分严重萎缩,甚至整株死亡,药害级别为5级。P15/浙粳//P12组合系列的水稻材料对草甘膦的耐性明显高于其它组合材料,可正常成熟结实,有一定的利用价值。本研究结果为耐草甘膦水稻育种提供了材料并奠定了理论基础。

The Effect on Germination and Seedlings of Wheat under Different Salt Stresses

[Objective] Wheat is the major grain crop in China. Salinization as an abi- otic stress has become an important limiting factor of wheat output. It has great sig- nificance to ensure the food security by improved the production of wheat in salin- ization of soil. [Method] This research is reference to previous study to be estab- lished by germination rate and seeding plants changes under salt stress to deter- mine the ability of salt tolerance of different wheat varieties. Under 300 mM NaCI to count germination rate and measuring the height, root length and root number of seeding in 200 mM and 400 mM NaCI to evaluated wheat varieties resistant to salt. [Result] Under this method, we found 3 grade-1 salt-tolerant varieties, 3 grade-2 salt-tolerant varieties, 5 grade-3 salt-tolerant varieties. [Conclusion] This study re- duced the work of salt-tolerance of wheat germplasm identification in salt pool. What＇s more, this study enriches the salt-tolerance of wheat germplasm resources, and provides a theoretical and technical support of wheat salt-tolerance breeding.

油菜响应水分胁迫的生理机制及栽培调控措施研究进展

油菜在整个生育期中对水分要求严苛,而随着全球气候变暖及强降雨事件的发生,油菜生产环境恶化,干旱和淹水交替发生,对油菜的生育进程及代谢过程产生了显著影响,使油菜产量降低、品质变劣。一播全苗是作物高产稳产的基础,油菜播种后的水分条件很大程度决定了成苗数量,而成苗后各生育期的水分条件在油菜生产中的作用同样不容小觑,决定了油菜最终的生产效益。在面临水分胁迫的过程中,油菜根系优先感应到干旱/淹水信号,同时地上部发生气孔关闭、光合作用减弱及渗透调节等一系列生理反应,地上部-地下部同时启动相应机制以对抗水分逆境,而现有的研究中尚未对油菜根-冠互作进行深入剖析。

Application of Clustering-based Decision Tree in the Screening of Maize Germplasm

[Objective] This paper aims to construct an improved fuzzy decision tree which is based on clustering,and researches into its application in the screening of maize germplasm.[Method] A new decision tree algorithm based upon clustering is adopted in this paper,which is improved against the defect that traditional decision tree algorithm fails to handle samples of no classes.Meanwhile,the improved algorithm is also applied to the screening of maize varieties.Through the indices as leaf area,plant height,dry weight,potassium（K） utilization and others,maize seeds with strong tolerance of hypokalemic are filtered out.[Result] The algorithm in the screening of maize germplasm has great applicability and good performance.[Conclusion] In the future more efforts should be made to compare improved the performance of fuzzy decision tree based upon clustering with the performance of traditional fuzzy one,and it should be applied into more realistic problems.

Thermal tolerance evaluation and related microsatellite marker screening and identification in the large yellow croaker Larimichthys crocea

Thermal tolerance to high temperature was evaluated in the large yellow croaker Larimichthys crocea. The survival thermal maximum for L. crocea was 33.0℃, the 50% critical thermal maximum （50% CTMax） was 35.5℃, and the critical thermal maximum （CTMax） was 36.0℃. Three microsatellite markers （LYC0148, LYC0200 and LYC0435）, associated with thermal tolerance were screened and identified using a Bulked Segregation Analysis （BSA） method. These markers have six amplified fragments in which four are related to thermal tolerance. These fragments were cloned and sequenced, and the results showed the core motif were all ＂AC＂ repeats. For LYC0148 and LYC0200, the lengths of fragments are 18l bp and 197 bp, respectively. For LYC0435, which has two fragments, the fragment lengths are 112 bp and 100 bp. The results provide useful molecular markers for thermal-tolerance breeding of large yellow croaker in the near future.

改良锰矿渣中木本植物筛选及锰的亚细胞分布和化学形态

针对锰矿矿渣土壤结构不良、养分少、重金属含量高的特点,及修复植物大多为草本植物的问题,在改良锰矿矿渣(对照CK:100%矿渣+0.1 kg磷肥;改良A:80%矿渣+20%泥炭土+0.1 kg磷肥;改良B:70%矿渣+30%泥炭土+0.1 kg磷肥;改良C:60%矿渣+40%泥炭土+0.1 kg磷肥)种植条件下,对湖南本土的14种木本植物进行耐性筛选,并对长势良好的耐性植物的亚细胞分布和化学形态进行了分析。结果表明:1)植物长势、生物量、株高增量、重金属的吸收量及转移量系数均呈现改良组>对照组的规律,但改良组之间不同的植物品种存在差异,总体上泡桐、夹竹桃、栾树、乌桕表现出较好的耐性。2)Mn在泡桐、夹竹桃各部位的亚细胞分布以细胞壁为主,在栾树、乌桕各部位以细胞壁和可溶性组分为主,两者共占总量的85%～99%,在线粒体、叶绿体和细胞核等细胞器中分布均很少。3)Mn在植物各部位的化学形态以氯化钠、水提取态为主,共占47%～81%,其次是醋酸态。相比于对照组,改良组对各部位Mn的化学形态的影响因植物品种不同而存在差异。

Variation in copper and zinc tolerance and accumulation in 12 willow clones： implications for phytoextraction

Willows （Salix spp.） have shown high potential for the phytoextraction of heavy metals. This study com- pares variations in copper （Cu） and zinc （Zn） tolerance and accumulation potential among 12 willow clones grown in a nutrient solution treated with 50 pmol/L of Cu or Zn, respectively. The results showed differences in the tolerance and accumulation of Cu and Zn with respect to different species/clones. The biomass variation among clones in response to Cu or Zn exposure ranged from the stimulation of growth to inhibition, and all of the clones tested showed higher tolerance to Cu than to Zn. The clones exhibited less variation in Cu accumulation but larger variation in Zn accumulation. Based on translocation factors, it was found that most of the Cu was retained in the roots and that Zn was more mobile than Cu for all clones. It is concluded that most willow clones are good accumulators of Zn and Cu.