冷诱导下毛百合甘油-3-磷酸酰基转移酶活性变化及其基因保守区的克隆

探讨了野生毛百合甘油-3-磷酸酰基转移酶活性在冷胁迫下的变化,用简并引物扩增了甘油-3-磷酸酰基转移酶基因保守区序列的结果表明,该保守区段长744 bp,推测编码247个氨基酸.在GPAT氨基酸序列中存在1个高度保守的区域(WIAPSGGRDRP),在NCBI上经过BLASTp比对分析,发现这段保守区序列为LPLAT基...     

基于GIS的生态脆弱区林地生态适宜性研究

为了探讨生态脆弱区林地生态适宜性评价机制,在对广西南丹县典型样地共41个作业区调查基础上,综合考虑与林地生态适宜性密切相关的地形地貌、土壤、植被等因素,利用ARCGIS分析方法对空间数据进行组织与计算,结合AHP方法研究各参评因子权重,并选择适当的隶属函数和模糊算法对南丹县林地生态适宜性进行模糊综合评判。结果表明：林地生态适宜性各等级比重排序为：III级（45.62%）＞IV级（27.84%）＞V级（17.61%）＞II级（8.93%）＞I级（0%）,整体隶属度值为3.5413,位于IV级水平;影响因子排序为：坡度＞石砾含量＞高程＞土层厚度＞郁闭度＞坡向＞灌木覆盖度＞草本覆盖度。同时,根据研究结果,分析了林地生态适宜性较差的主要原因及生态恢复重建的重点。     

草酸处理对库尔勒香梨黑斑病抑制效果的研究

分别采用50、100、400 mmol·L-1浓度的草酸溶液浸泡库尔勒香梨10 min,以蒸馏水处理为对照,晾干后,损伤接种黑斑病病原菌,分析香梨果实常温(25℃)贮藏9 d期间病斑及相关抗性生理指标的变化,研究不同浓度的草酸处理对库尔勒香梨黑斑病的抑制效果。结果表明,各组草酸处理可显著提高香梨果实的过氧化物酶(POD)、超氧化物歧化酶(SOD)、多酚氧化酶(PPO)、几丁质酶活性,增强抗病性,降低果实细胞渗透率,抑制接种后黑斑病面积与深度的扩展。综合各项指标,其中有效提高库尔勒香梨抗病性的最佳草酸处理浓度为100 mmol·L-1。     

基于SSR分子标记的Nicotiana tobacum–N.plumbaginifolia异源染色体植株的鉴定与筛选

以烟草(Nicotiana tabacum)品种云烟87的八倍体(2n=8x=96)和野生烟草N. plumbaginifolia (2n=2x=20)的基因组DNA为模板,对340对烟草SSR引物进行筛选以获得能扩增多态性条带的引物。利用多态性引物对种间杂交后代及190株回交后代的基因组DNA进行扩增,并对N.plumbaginifolia中的SSR标记的连锁情况进行简要分析。经筛选获得了多态性引物29对。结果显示,在190株后代中, 159株的基因组DNA能扩增出N. plumbaginifolia的特异SSR位点,可以判定该159株为N. tabacum的N. plumbaginifolia异源染色体植株,其余31株植株可能不含有N. plumbaginifolia的染色体。经UPGMA聚类分析,本群体中植株的遗传多样性较为丰富,部分分子标记在后代中的出现具有完全相关性。29个标记中14个可确定来源于5条不同染色体,N.plumbaginifolia的29个位点在回交后代中的扩增效率并不相同,且效率均较低(低于31.00%),说明该杂种中N. plumbaginifolia基因组的垂直传递效率较低。利用SSR分子标记可以判定云烟87八倍体与N.plumbaginifolia杂交获得的后代为真杂种,且自该远缘杂种回交后代中筛选获得大量异源染色体植株。这些结果和筛选获得异源染色体植株为进一步创制N.tabacum-N.plumbaginifolia抗黑胫病单体附加系以及易位系奠定了基础。     

水稻多基因型种群品种不同生态稻区的适应性研究

旨在探究水稻多基因型种群品种在不同生态稻区的适应性和稳定性,为多基因型种群品种的推广提供依据。选用参试品种‘尤群6号’、‘南八糯’和对照品种‘红优7号’开展田间试验,通过抗病性、农艺性状等指标进行综合评价。结果表明：参试品种‘尤群6号’(0.40~0.95 kg/m2)和‘南八糯’(0.81~1.04 kg/m2)在4个稻区产量显著高于对照品种（尤群6号在文山地区表现除外）;田间发病总体较轻,个别品种在局部试验点表现有差异,‘尤群6号’在文山稻瘟病发生 (DI=48.66)和粳稻区楚雄稻曲病发生相对较重,仍需继续种植综合观察;品种生育期随试验点海拔的升高而缩短,株高随月平均气温升高而增高,品种内株高变异系数介于1.97~6.13之间。研究表明参试品种在籼粳混栽区红河表现最佳,籼稻区德宏表现较好,在文山、楚雄田间表现有待继续评价;总体上,表现出较好适应性和稳定性。     

硝酸稀土对鲫鱼生长及营养状况的影响

在鲫鱼的饲料中添加不同浓度的硝酸稀土进行对比试验,研究稀土元素对鲫鱼生长性能和体内代谢的影响。结果表明,添加45mg/kg的硝酸稀土效果最为明显,可以大大提高鲫鱼的生长速度,显著降低饲料系数（p﹤0.01）、增强抗病力、降低死亡率,还可明显提高鱼体蛋白质和脂肪的含量（p﹤0.05）。     

重庆农村黑臭水体水质及底泥氮磷污染分析

对84个重庆市农村黑臭水体水质和底泥氮磷的监测数据进行统计及相关性分析,并利用综合污染指数法和有机指数法对水质和底泥污染状况进行评价。结果表明,87%的黑臭水体水质存在不同程度的氮磷污染,且50%的水体同时存在氮磷超标,河沟、沟渠较塘氮污染更为严重;底泥均受总氮、有机氮、总磷污染,70.2%的底泥存在有机污染。水质中总磷、总氮、氨氮3个指标之间存在显著正相关,底泥中有机质、总氮、总磷之间不存在显著相关关系。底泥中总磷与水质中总磷存在显著正相关关系,但相关性较弱,底泥中全氮与水质中总氮不存在显著相关关系。总体上重庆市农村黑臭水体氮磷污染以外源污染为主。     

小型植保无人机超低量喷雾对荒漠绿洲麦区小麦白粉病的防治效果

研究小型植保无人机超低量喷雾对小麦白粉病的防治效果,为科学使用小型植保无人机防控小麦病害提供指导。采用随机区组的方法,定点调查各处理小麦白粉病发生情况,评价供试药剂对小麦白粉病的防治效果。结果表明,240 g/L氯氟醚·吡唑酯SC 180 g/hm²、19%啶氧·丙环唑SC 199.50 g/hm²和 23%醚菌·氟环唑 SC 103.50 g/hm²添加增效剂迈飞对小麦白粉病具有较好的防效,防效分别为77.88%、74.23%和 73.26%。42%苯菌酮 SC 189.00 g/hm²、430 g/L戊唑醇悬浮剂SC 129.00 g/hm²、75%肟菌·戊唑醇 WG 202.50 g/hm²和 40%腈菌唑 WP 120.00 g/hm²添加增效剂迈飞对小麦白粉病防效在60.90%～65.72%之间。7 种药剂均可用于小型植保无人机超低量喷雾防治小麦白粉病,为了减缓抗药性的产生,建议在生产上轮换使用。     

Fine mapping of the gene for susceptibility to black spot disease in Japanese pear (Pyrus pyrifolia Nakai)

Black spot disease, which is caused by the Japanese pear pathotype of the filamentous fungus Alternaria alternata (Fries) Keissler, is one of the most harmful diseases in Japanese pear cultivation. We mapped a gene for susceptibility to black spot disease in the Japanese pear (Pyrus pyrifolia Nakai) cultivar ‘Kinchaku’ (Aki gene) at the top of linkage group 11, similar to the positions of the susceptibility genes Ani in ‘Osa Nijisseiki’ and Ana in ‘Nansui’. Using synteny-based marker enrichment, we developed novel apple SSR markers in the target region. We constructed a fine map of linkage group 11 of ‘Kinchaku’ and localized the Aki locus within a 1.5-cM genome region between SSR markers Mdo.chr11.28 and Mdo.chr11.34. Marker Mdo.chr11.30 co-segregated with Aki in all 621 F₁ plantlets of a ‘Housui’ × ‘Kinchaku’ cross. The physical size of the Aki region, which includes three markers (Mdo.chr11.28, Mdo.chr11.30, and Mdo.chr11.34), was estimated to be 250 Kb in the ‘Golden Delicious’ apple genome and 107 Kb in the ‘Dangshansuli’ Chinese pear genome. Our results will help to identify the candidate gene for susceptibility to black spot disease in Japanese pear.     

Karyotype analysis and physical mapping of 45S rRNA genes in Hydrangea species by fluorescence in situ hybridization

Detailed karyotypes of Hydrangea macrophylla, Hydrangea paniculata and Hydrangea quercifolia were constructed on the basis of arm lengths and centromeric index, together with 45S rDNA fluorescence in situ hybridization. Although the chromosomes were small, they were well distinguishable for all species. Chromosome morphology and karyotypes were different for the three species. H. macrophylla had six metacentric (M), eight submetacentric (SM) and four subtelocentric (ST) chromosomes. The karyotype of H. paniculata contained seven M, 10 SM and one ST chromosomes and H. quercifolia had six M, 10 SM and two ST chromosomes. The variability among three species also was expressed by 45S rDNA signals. H. macrophylla had a nucleolar organizing region on chromosome 2, H. paniculata had 45S rDNA signals on chromosomes 2, 5 and 11 and H. quercifolia on chromosomes 3 and 8. Hybridization signal always was distally on the short arm but the strength of the signals was different for the three species. The chromosome portraits made in this study will be used to trace chromosome behaviour in interspecific hybrids resulting from breeding work between the three species.