New fossil hangingflies (Insecta: Mecoptera: Raptipedia: Cimbrophlebiidae) from the Middle Jurassic of Inner Mongolia,China

Abstract: Two new genera with six new species of hangingflies (Mecoptera: Raptipedia: Cimbrophlebiidae) are described. They were collected from the Middle Jurassic nonmarine sedimentary strata of the Jiulongshan Formation in Daohugou, Inner Mongolia, north‐eastern China. This report of Cimbrophlebiidae from the Yanliao Biota provides detailed morphological information and evidence of a broad diversity of Cimbrophlebiidae during the Middle Jurassic. A key to the known species of Cimbrophlebiidae is provided.     

Rhizospheric NO affects N uptake and metabolism in Scots pine (Pinus sylvestris L.) seedlings depending on soil N availability and N source

We investigated the interaction of rhizospheric nitric oxide (NO) concentration (i.e. low, ambient or high) and soil nitrogen (N) availability (i.e. low or high) with organic and inorganic N uptake by fine roots of Pinus sylvestris L. seedlings by ¹⁵N feeding experiments under controlled conditions. N metabolites in fine roots were analysed to link N uptake to N nutrition. NO affected N uptake depending on N source and soil N availability. The suppression of nitrate uptake in the presence of ammonium and glutamine was overruled by high NO. The effects of NO on N uptake with increasing N availability showed different patterns: (1) increasing N uptake regardless of NO concentration (i.e. ammonium); (2) increasing N uptake only with high NO concentration (i.e. nitrate and arginine); and (3) decreasing N uptake (i.e. glutamine). At low N availability and high NO nitrate accumulated in the roots indicating insufficient substrates for nitrate reduction or its storage in root vacuoles. Individual amino acid concentrations were negatively affected with increasing NO (i.e. asparagine and glutamine with low N availability, serine and proline with high N availability). In conclusion, this study provides first evidence that NO affects N uptake and metabolism in a conifer.     

Arabidopsis ROP‐interactive CRIB motif‐containing protein 1 (RIC1) positively regulates auxin signalling and negatively regulates abscisic acid (ABA) signalling during root development

Auxin and abscisic acid (ABA) modulate numerous aspects of plant development together, mostly in opposite directions, suggesting that extensive crosstalk occurs between the signalling pathways of the two hormones. However, little is known about the nature of this crosstalk. We demonstrate that ROP‐interactive CRIB motif‐containing protein 1 (RIC1) is involved in the interaction between auxin‐ and ABA‐regulated root growth and lateral root formation. RIC1 expression is highly induced by both hormones, and expressed in the roots of young seedlings. Whereas auxin‐responsive gene induction and the effect of auxin on root growth and lateral root formation were suppressed in the ric1 knockout, ABA‐responsive gene induction and the effect of ABA on seed germination, root growth and lateral root formation were potentiated. Thus, RIC1 positively regulates auxin responses, but negatively regulates ABA responses. Together, our results suggest that RIC1 is a component of the intricate signalling network that underlies auxin and ABA crosstalk.     

小钻‘白城杨2号’小孢子发生及花粉大小变异

利用醋酸洋红染色压片技术,以温室水培小钻‘白城杨2号’(Populus×xiaozhuanica W.Y.Hsu et Liangcv.‘Baicheng-2’)为材料,对其小孢子发生过程中染色体行为及花粉大小变异进行研究。结果表明:(1)‘白城杨2号’小孢子母细胞减数分裂过程中染色体行为存在一定比例的异常现象,包括终变期单价体、中期Ⅰ染色体提前分离、后期Ⅰ和Ⅱ落后染色体和染色体桥、末期Ⅰ和Ⅱ微核、中期Ⅱ纺锤体定位异常以及胞质分裂异常等,这些异常现象的发生与‘白城杨2号’杂种起源有密切关系。(2)‘白城杨2号’小孢子母细胞减数分裂过程中核仁数目存在动态变化,末期Ⅰ和Ⅱ的子核中最多可看到8个小核仁,可能与杨属树种的多倍体起源有关,其染色体组中可能包含8对具核仁组织者区的染色体。(3)‘白城杨2号’产生空瘪花粉率为3.67%,饱满花粉直径在21.3～52.2μm之间,频率分布总体呈近似高斯分布,0.69%的花粉直径超过37μm,表明其可能产生少量未减数的2n花粉。     

盐胁迫下施肥对棉花生长及氮素利用的影响

利用海水配制不同含盐量(0、0.15%、0.3%)的土壤盆栽棉花,在可移动遮雨棚内研究了不同施肥(N、NK、NP、NPK)处理对棉花生长、氮素吸收与利用的影响.结果表明: 盐胁迫和施肥均影响棉花生物产量、棉株氮素农学利用效率、氮素生物利用效率和氮素积累量,且两者存在显著的互作效应.施肥能提高盐胁迫下棉株氮素利用效率及氮素积累量,并显著增产,不同施肥处理中以N、P、K肥料配合施用的效果最好;施肥效果受盐胁迫程度的影响,低盐胁迫(0.15%)下的施肥效果好于中度盐胁迫(0.3%).     

元宝草中一个新的二苯甲酮

为了研究元宝草(Hypericum sampsonii Hance)全草的化学成分,利用硅胶柱层析、Sephadex LH-20等色谱技术对元宝草三氯甲烷部位进行分离和纯化,共得到6个化合物,通过1H NMR、13C NMR、HMQC、HMBC等波谱技术分别鉴定为2,6-二羟基-4,3’,5’-三甲氧基二苯甲酮(1)、1,3,6-三羟基-2-甲基蒽醌(2)、山奈酚(3)、木犀草素(4)、3,4-二羟基苯甲酸乙酯(5)、β-谷甾醇(6),其中化合物1为新化合物,化合物2和5首次从该植物中分离得到。     

绵地花菌(Albatrellus ovinus)中的grifolin及其衍生物

本文对高等真菌绵地花(Albatrellus ovinus)进行了化学成分的研究。利用各种柱色谱方法(包括正相硅胶、反相硅胶、Sephadex LH-20凝胶色谱、中压液相色谱、半制备HPLC等),分离得到grifolin及其它的5个衍生物。分别为grifolin(1)、neogrifolin(2)、grifolinone A(3)、grifolinone C(4)、confluentin(5)和4-O-methylgrifolic acid(6)。这些化合物的结构通过波谱学方法以及与文献数据对照进行确定。化合物3～6为首次从该种高等真菌中分离得到。化合物4为一个真菌色素,它是一个由一分子的grifolin和一分子苯醌化的grifolin以头对头的方式聚合而成的二聚体。     

胎次、性别对成年小鼠海马齿状回神经发生及学习记忆的影响

目的探讨胎次、性别是否对成年小鼠海马齿状回神经发生及学习记忆产生影响。方法运用Morris水迷宫系统检测第1～3胎成年小鼠的学习记忆能力,腹腔注射BrdU,标记神经干细胞,检测不同胎次、性别小鼠海马齿状回中的神经发生的差异。结果 （1）在同性别、不同胎次成年小鼠间,第2胎的学习记忆能力（LMA）均显著地高于第1、3胎的,其影响规律为LMA2〉LMA1〉LMA3,且P〈0.05;在同胎次、不同性别成年小鼠间,雌性小鼠的LMA均高于雄性小鼠的,但其差异无显著性（P〉0.05）。（2）在同性别、不同胎次成年小鼠间,第2胎海马DG新生神经细胞的数量（N）均高于第1、3胎的,其影响规律分别为NF2〉NF3〉NF1和NM2〉NM1〉NM3,但其差异无显著性（P〉0.05）;在同胎次、不同性别成年小鼠间,雌性小鼠的N均高于雄性小鼠的,但其差异无显著性（P〉0.05）。结论胎次、性别对实验动物神经发生及学习记忆等方面产生的影响是肯定的。因此,在使用实验动物时,应予以充分考虑,尽量使用胎次、性别相同的。