施用锌肥和遮阴互作对花生生长发育、抗病性及产量的影响

采用大田裂区试验，研究了施用锌肥和不同遮阴程度互作对花生生长发育、抗病性及产量的影响。结果表明，与不施锌肥相比，施用锌肥能提高花生不同部位锌含量、增加叶片SPAD值，提高花生叶片中可溶性糖、蛋白质和生长素含量，减少花生病害的发生，平均降低7.1个百分点，花生产量平均增加19.4%。相同施锌水平下，随着遮阴程度的增加，花生不同部位锌的含量和不同生育期叶片SPAD值以及花生叶片中可溶性糖、蛋白质和生长素含量呈增加趋势，花生的发病率比不遮阴对照增加4.8、10.2个百分点，花生产量平均降低16.5%、10.0%。在30%、70%的遮阴条件下，施用锌肥的花生产量比不施锌的分别提高21.1%、25.0%。本试验条件下，施用七水硫酸锌30 kg/hm2，使花生具有较强的抗低温寡照能力及抗病性能，增产显著，可在花生产区推广应用。     

朝鲜黄杨种源试验苗期效果初报

利用引进的锦州、沈阳、大连、鞍山4个产地朝鲜黄杨(Buxus microphylla var.koreana)种源进行播种试验,对幼苗出苗率、保存率、苗高、地径、分枝数、冠幅调查测量。结果表明:4个种源的出苗率、当年苗高、分枝数、冠幅均存在显著差异,地径差异不显著。沈阳种源播种出苗率最高,为75.48%;沈阳、大连种源当年苗高14.53 cm、14.08 cm,分枝数9.43条、9.21条,冠幅12.02 cm、10.00 cm,显著高于鞍山、锦州种源;苗木越冬保存率均在90%以上。沈阳种源表现最好。鞍山和锦州种源表现较差。     

Early stages of Margaritifera margaritifera glochidiosis in Atlantic salmon: Morphopathological characterization

Freshwater mussels of the order Unionida encyst into the fish mucosa to metamorphose and complete their life cycle, causing a parasitic disease known as glochidiosis. This parasitic stage represents a bottleneck for the survival of naiads, particularly for critically endangered species as Margaritifera margaritifera; however, little is known about the events occurring during this critical stage. Therefore, this study aimed to histologically characterize the development of M. margaritifera glochidiosis in Atlantic salmon to get insight into the pathogenesis of this interaction. Fish exposed to glochidia were sampled during the first 44 days post-exposure, and organs were observed by stereomicroscopy and light microscopy. Glochidia attached to the gills by pinching the lamellar epithelium, whereupon an acute proliferative branchitis engulfed most of the larvae. However, during the first 14 days, a severe detachment of unviable glochidia occurred, associated with the presence of pleomorphic inflammatory infiltrate and epithelial degeneration. In the cases where larvae remained attached, a chronification of the lesions with none to scarce inflammation was observed. These results provide key information to better understand the complex host–parasite interaction during the early stages of glochidiosis and provide valuable information to optimize artificial rearing of naiads in conservation of threatened freshwater mussel populations.     

氮磷钾用量对小麦冠层不同层次光截获和干物质分配的影响

为明确不同氮、磷、钾用量对小麦冠层不同层次光截获和干物质分配的影响，以济麦22为供试材料，设置F0（不施肥）、F1（N 180 kg·hm^-2，P₂O₅ 75 kg·hm^-2，K₂O 60 kg·hm^-2）、F2（N 225 kg·hm^-2，P₂O₅ 120 kg·hm^-2，K₂O 105 kg·hm^-2）和F3（N 270 kg·hm^-2，P₂O₅ 165 kg·hm^-2，K₂O 105 kg·hm^-2）4个施肥量处理，比较分析开花后不同氮、磷、钾用量对小麦叶面积指数、冠层不同层次光截获特性和成熟期干物质分配的影响。结果表明，F1处理下叶面积指数显著高于F0处理，而与F2和F3处理间无显著差异；开花后15 d，F1处理下小麦冠层不同层次及总PAR截获率和截获量均显著高于F0处理，而与F2和F3处理间无显著差异。F1处理下成熟期干物质在小麦冠层不同层次营养器官中的分配量、籽粒中的分配量及总干物质积累量显著高于F0处理，而与F2和F3处理间无显著差异。成熟期干物质在小麦冠层不同层次营养器官和籽粒中的分配量以及总干物质积累量与冠层上层（顶部至株高2/3）、中层（株高2/3至株高1/3）和总PAR截获率均呈显著正相关。F1处理（N 180 kg·hm^-2，P₂O₅ 75 kg·hm^-2，K₂O 60 kg·hm^-2）为本试验条件下的最优处理。     

Basal internode elongation of rice as affected by light intensity and leaf area

Short basal internodes are important for lodging resistance of rice(Oryza sativa L.).Several canopy indices affect the elongation of basal internodes,but uncertainty as to the key factors determining elongation of basal internodes persists.The objectives of this study were(1)to identify key factors affecting the elongation of basal internodes and(2)to establish a quantitative relationship between basal internode length and canopy indices.An inbred rice cultivar,Yinjingruanzhan,was grown in two split-plot field experiments with three N rates(0,75,and 150 kg N ha−1 in early season and 0,90,and 180 kg N ha−1 in late season)as main plots,three seedling densities(16.7,75.0,and 187.5 seedlings m−2)as subplots,and three replications in the 2015 early and late seasons in Guangzhou,China.Light intensity at base of canopy(Lb),light quality as determined from red/far-red light ratio(R/FR),light transmission ratio(LTR),leaf area index(LAI),leaf N concentration(NLV)and final length of second internode(counted from soil surface upward)(FIL)were recorded.Higher N rate and seedling density resulted in significantly longer FIL.FIL was negatively correlated with Lb,LTR,and R/FR(P<0.01)and positively correlated with LAI(P<0.01),but not correlated with NLV(P>0.05).Stepwise linear regression analysis showed that FIL was strongly associated with Lb and LAI(R2=0.82).Heavy N application to pot-grown rice at the beginning of first internode elongation did not change FIL.We conclude that FIL is determined mainly by Lb and LAI at jointing stage.NLV has no direct effect on the elongation of basal internodes.N application indirectly affects FIL by changing LAI and light conditions in the rice canopy.Reducing LAI and improving canopy light transmission at jointing stage can shorten the basal internodes and increase the lodging resistance of rice.     

华北地区夏玉米生产中磷素利用特征研究

为评估当前中国华北地区夏玉米生产中的磷素利用效率和影响因素,促进磷肥资源高效利用和降低损失和污染,本研究通过收集1980年以来公开发表的夏玉米田间试验的文献,对华北地区夏玉米磷肥试验数据进行收集、整理和分析,获得了夏玉米的籽粒与秸秆产量及其比例,以及施磷量与籽粒和秸秆磷含量的关系模型。研究发现,随着施磷量的增加,土壤-夏玉米作物系统的磷素表观盈亏量呈线性增加,在施磷达到75 kg/hm ²时,磷素表观盈亏量为0。华北地区的夏玉米磷肥平均利用效率约为15%;增加氮肥施用量以及与磷合理配施有利于提高磷肥利用效率。整体上,夏玉米对磷酸二铵的利用效率高于过磷酸钙;有机肥和化肥配施可以有效提高磷肥利用效率。夏玉米‘天泰60’品种的磷肥利用效率最高。在华北地区夏玉米生产中,选用磷酸二铵以及适合的氮肥水平、有机肥与化肥配施,可以提高磷肥利用效率,降低磷肥损失和环境污染风险。     

厚皮甜瓜新品种红宝玉的选育

红宝玉是以10R15 为母本、10R8 为父本选育而成的中熟厚皮甜瓜一代杂种。植株长势稳健，抗病抗逆性强。全生育期95～110 d（天），果实发育期30～35 d（天）。果实短椭圆形，成熟后果面乳白色，单果质量约1.5 kg，果肉橘红色，肉厚3.5～4.0 cm，腔小不发酵，中心可溶性固形物含量17.5%，肉质紧脆，不脱蒂，耐贮耐运。平均每667 m²产量3 600 kg 左右。适宜在山东、河北、陕西、安徽等地春季保护地设施栽培。     

Up-regulation of miR-181a attenuates releases of CSE-induced pro-inflammatory factors and expression of collagen IV,fibronectin and α-SMA in human bronchial epithelial cells

AIM: To investigate the effect and potential mechanism of microRNA-181a (miR-181a) on cigarette smoke extract (CSE)-induced the productions of pro-inflammatory factors and the expression of collagen IV, fibronectin and α-smooth muscle actin (α-SMA) in human bronchial epithelial cells (HBECs). METHODS: CSE-induced miR-181a expression was detected by RT-qPCR in the HBECs. After tansfected with miR-181a mimic, the releases of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6 and transforming growth factor-β1 (TGF-β1) were measured by ELISA, the protein expression of collagen IV, fibronectin and α-SMA was determined by Western blot. The activation of NF-κB/TGF-β1/Smad3 pathway was also evaluated by Western blot. RESULTS: CSE increased the levels of TNF-α, IL-1β, IL-6 and TGF-β1 and the expression of collagen IV, fibronectin and α-SMA, and decreased the expression of miR-181a in the HBECs (P<0.05). However, transfected with miR-181a mimic partially prevented the releases of TNF-α, IL-1β, IL-6 and TGF-β1, and inhibited the expression of collagen IV, fibronectin and α-SMA (P<0.05). Additionally, the activation of NF-κB/TGF-β1/Smad3 evoked by CSE was attenuated after transfected with miR-181a mimic. CONCLUSION: Up-regulation of miR-181a prevents the releases of CSE-induced pro-inflammatory factors and expression of collagen IV, fibronectin and α-SMA in the HBECs, and its mechanism may be related to the inhibition of NF-κB/TGF-β1/Smad3 pathway.     

Effect of miR-29b-mediated TGF-β/Smad signaling pathway on progression of hepatic fibrosis in rats

AIM: To investigate the role of microRNA-29b (miR-29b)-mediated TGF-β/Smad signaling pathway in the activation of hepatic stellate cells (HSC) and its effect on the progression of hepatic fibrosis in rats.METHODS: Hepatic liver fibrosis rat model was established, and its HSC were isolated. Normal rat HSC were also obtained and identified in vitro. RT-qPCR and Western blot were used to detect the alterations of miR-29b, TGF-β/Smad signaling pathway-related proteins and liver fibrosis marker proteins in the acquired cells. Finally, the direct targeting binding of miR-29b to TGF-β1 was identified by dual-luciferase reporter assay system.RESULTS: With the activation of HSC, the expression of miR-29b gradually decreased (P<0.01), while the expression of collagen type I and α-smooth muscle actin gradually increased (P<0.01). At the same time, the expression of Smad2/3/4 was significantly increased, and the expression of Smad7 was significantly decreased (P<0.01). Dual-luciferase reporter assay showed that miR-29b bound directly to "UCUCUCCGU" in the 3'UTR of TGF-β1, indicating that TGF-β1 was a downstream target gene of miR-29b.CONCLUSION: miR-29b may be involved in the inhibition of HSC activation and migration, thereby inhibiting the process of liver fibrosis. The biological function of miR-29b may be through the direct targeting of TGF-β1, thus regulating and inhibiting the TGF-β/Smad signaling pathway.     

豫北山区“粮—草—羊”高效平衡养羊模式现状

从粮食作物、经济作物及饲草的种植,饲草料的加工调制与利用,全舍饲肉羊的养殖及杂交繁育,以及羊粪尿的资源化利用等方面介绍了豫北山区“粮—草—羊”高效平衡养羊模式发展现状,以期为促进豫北山区资源可持续利用、山区生态环境良性循环和社会经济可持续发展提供思路。