缓释肥类型与运筹对不同穗型水稻产量的影响

以大穗型品种甬优2640和多穗型品种南粳9108为材料,270 kg hm–2纯氮条件下,选用树脂包衣(PCU)、硫包衣(SCU)和脲甲醛(UF)3种缓控释肥类型,设置了缓控释肥与尿素均基施、缓控释肥基施后分蘖期施尿素2种施肥方式,以常规尿素定量分施为对照(CK)。结果表明,缓控释肥的应用对甬优2640无增产效应。主要因为甬优2640穗大粒多,群体颖花量大。与CK比,相对集中在前中期的肥效难以满足植株全生育期生长,中后期叶面积指数下降快,氮素积累少,光合势弱,物质生产量不足,不能实现群体大库容的有效充实。而对南粳9108,脲甲醛基施+尿素分蘖期施处理比CK增产5.2%~5.9%,树脂包衣基施+尿素分蘖期施和脲甲醛+尿素均基施处理与CK平产的同时可减少施肥2~3次。2种运筹方式中,以缓控释肥基施后分蘖期施用尿素处理能有效增加植株茎蘖数,提高成穗率和最终穗数,扩大叶面积指数,增强光合势,增加干物质和氮素的积累,获得高产。3种肥料类型中,产量呈现UFPCUSCU。脲甲醛基施+分蘖期施尿素处理之所以能使南粳9108获得比CK更高的产量,是因为UF的肥效在中后期依然能相对稳定释放,配合尿素的分蘖期施用,既保证了前期分蘖的发生,又能保证高峰苗后稳定的茎蘖数和群体叶面积指数,植株在拔节后的光合势和物质积累量大,氮肥利用率高,增产显著。由此可见,针对不同穗型和产量特性的水稻品种,优选缓控释肥类型基施的同时,分蘖期配合速效肥料的施用,可获得既省工又增产的效果。     

Effects of CENP-W down-regulation on human glioma U87 cells

AIM: To study the effect of centromere protein W (CENP-W) down-regulation on human glioma U87 cells.METHODS: Small interfering RNA (siRNA) was used to inhibit the expression of CENP-W in the U87 cells. The interference effect of siRNA was evaluated by RT-qPCR and Western blot. The proliferation of the cells was analyzed by MTT assay, BrdU staining and colony formation experiment. Transwell chamber assay was used to detect the invasion ability of the cells. The cell migration ability was measured by a scratch test. The changes of the cell cycle distribution and apoptosis were analyzed by flow cytometry.RESULTS: The results of MTT assay, colony formation experiment and BrdU staining showed that the cell proliferation and colony formation abilities in experimental group were significantly lower than those in control group and negative control group. The results of Transwell and scratch experiments showed that the migration and invasion abilities in experimental group were weaker than those in blank control group and negative control group. The results of flow cytometry analysis showed that the cell cycle distribution in experimental group was arrested in G₀/G₁ phase. The percentage of apoptotic cells in experimental group was higher than that in control group (P<0.05).CONCLUSION: Down-regulation of CENP-W expression inhibits the proliferation, migration and invasion of human glioma cells and promotes the apoptosis of the cells, suggesting that CENP-W may be a potential target of gene therapy for human glioma.     

Effect of antisense locked nucleic acid blocking translation initiation region of c-myc exon 2 on apoptosis of hepatocellular carcinoma cells

AIM: To observe the effect of antisense locked nucleic acid (anti-LNA) blocking the translation initiation region of c-myc exon 2 on the viability and apoptosis of hepatocellular carcinoma cells.METHODS: The anti-LNA that was complementary to the translation initiation region of c-myc exon 2 was designed, synthesized, and introduced into the HepG2 cells by cationic liposome-mediated transfection. The mRNA and protein levels of c-Myc in the cells were determined by RT-PCR and Western blot. The change of cell apoptosis was analyzed by flow cytometry, and the toxicity of anti-LNA to the cells was detected by MTT assay.RESULTS: Five days after transfection, the mRNA level of c-Myc in anti-LNA group was 0.335±0.016, and the protein level was 0.448±0.037, significantly lower than those in control group (both P<0.05). The ratio of apoptotic cells in anti-LNA group was 32%±6%, which was higher than that in control group (P<0.05).CONCLUSION: Antisense locked nucleic acid targeting at the translation initiation region of c-myc exon 2 shows strong inhibitory effects on the apoptosis of hepatocellular carcinoma cells.     

观赏荷花新品种‘首领’

‘首领’是从观赏荷花‘钗头凤’芽变中选出的新品种,重台,小株型。立叶高20~30 cm,叶径13.5~26.5 cm×11~20 cm。花色为复色,花瓣外被18~22枚,内被122~140枚,花冠直径15.0~17.5 cm。着花密度较高,7~13朵·m~(-2)。     

乌腺金丝桃ISSR反应体系的构建及其遗传多样性分析

以14份乌腺金丝桃为试材,采用L_(16)(4~5)正交实验设计,建立并优化乌腺金丝桃的ISSR-PCR反应体系,并利用优化的反应体系分析供试材料间的遗传多样性。结果表明:20μL ISSR-PCR反应体系中应含有Taq DNA聚合酶1.0U,dNTPs 0.2mmol·L~(-1),Mg~(2+)2.0mmol·L~(-1),模板DNA 45ng。从45条ISSR引物中筛选出11条多态性引物,利用筛选的多态引物对14份乌腺金丝桃材料进行了ISSR遗传多样性分析,共扩增出85条带,其中多态性条带57条,占67.06%;4个乌腺金丝桃居群的遗传相似系数介于0.375 1~0.725 2,平均值为0.541 6;通过UPGMA进行聚类分析表明,14份材料可分为3个类群4个亚群。乌腺金丝桃居群间遗传多样性水平明显高于居群内,其遗传距离与地理距离具有一定的相关性。     

杜鹃红山茶优良无性系遗传多样性的ISSR分析

以39个杜鹃红山茶优良无性系为试材,采用ISSR分子标记方法,研究杜鹃红山茶优良无性系遗传多样性。结果表明:杜鹃红山茶无性系遗传多样性较高,采用筛选的26个ISSR引物共扩增出211个位点,多态位点180个,多态位点百分率(PPB)为85.3%,有效等位基因数1.6,Nei′s基因多样性指数(H)为0.345 1,Shannon多态性信息指数(I)为0.510 6,相似性系数为0.488 2~0.815 2,平均为0.668 8。UPGMA聚类分析得出,在遗传距离为0.360时,所有供试材料可以分为两大类:第Ⅰ类群是由4号和5号无性系组成,其它无性系构成第Ⅱ类群;当遗传距离为0.304时,又可将第Ⅱ类群分为6组。     

我国本地假俭草的特性与应用

在简要介绍假俭草的生态分布及生境类型的基础上,详细介绍了假俭草的耐荫、抗病、抗虫、耐践踏、耐瘠薄、耐旱、耐寒、耐药、抗污染等特性,并与其它暖季型草种进行了比较。回顾了假俭草遗传多样性研究、育种等方面的进展及应用情况。提出假俭草新品种可实现草坪的"少修剪、不打药、不施肥、不灌溉"的低养护管理目标,其推广应用可最大限度地降低草坪的养护成本,为我国城市绿地及球场建设做出贡献。建议在广泛收集全国野生假俭草种质资源的基础上,加强新品种选育工作,培育优良品系,加大引种繁育力度,扩大其适应地域,以提高假俭草利用率,促进我国草业的发展。     

北京鹫峰国家森林公园蜡梅品种调查及其园林应用

以北京鹫峰国家森林公园为研究对象,采用全面调查与系统诊断的方法,对北京鹫峰国家森林公园现有蜡梅进行了品种调查与分类,以期摸清北京鹫峰国家森林公园的蜡梅品种情况。结果表明:北京鹫峰目前栽培的蜡梅品种有13个,按照内被片紫纹的多少分为3个品种群,分别为素心蜡梅品种群(Ch.praecoxConcolor Group)、乔种蜡梅品种群(Ch.praecoxIntermedius Group)和红心蜡梅品种群(Ch.praecoxPatens Group),并分别描述了其主要特征;同时,蜡梅在北京各类园林中的应用已日趋多样。     

不同灌溉方式对北京春茬露地生菜的影响

为了探索适宜于北京春茬露地生菜的灌溉方式,以生菜品种"雷达"为研究对象,设置3个灌溉处理,以常规灌溉为对照,研究不同灌溉方式对生菜生长、品质和产量的影响。结果表明:常规灌溉处理的株高和叶片数显著低于微喷带和边缝式滴灌带处理;边缝式滴灌带处理的单方水产出最高,且其植株硝酸盐显著低于微喷带处理,维生素C含量要显著高于微喷带处理和常规灌溉处理,果实营养价值和安全性相对较高。综合考虑植株生长、品质、产量和单方水产出率等要素,边缝式滴灌带相对适宜春茬露地生菜的生产,其产量667m~2达到了2 797kg,单方水产出率达到31.3kg·m~(-3),单方水产出率比微喷带处理和常规处理分别高20.8%和233.0%。试验还得出了春茬露地生菜各生育时期的作物系数,能够为实现春茬露地生菜的高效生产提供一定的参考依据。     

叶面喷施硝酸铵对两种黄瓜苗期生理指标的影响

以广泛种植的2个黄瓜品种"长春密刺"和"水果黄瓜"为试材,叶面喷施0.30%、0.60%、0.90%硝酸铵,研究了不同浓度硝酸铵对幼苗鲜质量、叶绿素含量、渗透调节物质及酶活性等生理指标的影响,为有效且合理地施用氮肥提供参考依据。结果表明:喷施硝酸铵可提高2种黄瓜幼苗的鲜质量,对叶绿素a含量影响不大,促进叶绿素b含量和叶绿素总量的增加;随着喷施硝酸铵浓度的增大,可提高2种黄瓜的游离脯氨酸含量,降低可溶性糖含量,对可溶性蛋白质含量影响不明显;随着喷施硝酸铵浓度的增大,2种黄瓜的超氧化物歧化酶(SOD)活性变化趋势均为先增后降,而过氧化氢酶(CAT)活性变化趋势则呈现出先降后升,但较对照差异均不显著;"长春密刺"和"水果黄瓜"的叶面喷施硝酸铵最适浓度分别是0.30%和0.60%。