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。     

朱顶红幼嫩花梗胚性愈伤组织诱导和高效植株再生

为建立高效的朱顶红植株再生和种苗繁育技术体系,以幼嫩花梗为外植体开展胚性愈伤组织诱导和植株再生研究。对2,4-D和噻苯隆（TDZ）浓度、外植体发育时期及大小进行了筛选,结果表明：将切片厚度为1 mm的幼嫩花梗外植体置于添加0.5 mg ? L-1 TDZ 和2.0 mg ? L-1 2,4-D的MS固体培养基上培养8周,胚性愈伤组织诱导率最高,达85.3%。将胚性愈伤组织转移至相同的培养基上,每月继代1次,平均每月增殖10.6倍。在不含任何生长调节剂的MS培养基上,胚性愈伤组织的植株再生率达98.0%,平均每块愈伤组织可再生出12.3个小植株。经过36次（3年）继代培养后,胚性愈伤组织的增殖和植株再生效率没有显著变化。幼苗移栽至温室驯化,成活率达97.5%。再生植株移栽到田间,没有发现明显的表型变异。对随机选择的再生植株和母株进行简单序列重复区间（ISSR）扩增分析,证实再生植株没有发生DNA水平变异。     

辣椒遗传育种研究进展

对近年来辣椒遗传育种研究进展,从种质资源、基因组、遗传机制、育种方法、育成品种等几个方面进行了综述,并根据目前产业现状和国际研究热点对今后发展进行了展望。     

Roles of protein phosphatase 4 in down-regulation of eNOS Ser633 phosphorylation induced by palmitic acid in human umbilical vein endotheli?al cells

AIMTo investigate the roles of protein phosphatase 4 (PP4) in down-regulation of endothelial nitric oxide synthase (eNOS) Ser633 phosphorylation induced by palmitic acid (PA). METHODSHuman umbilical vein endothelial cells (HUVECs) were treated with PA at 25 μmol/L, 50 μmol/L, 100 μmol/L and 200μmol/L for 36 h, or treated with PA at 100 μmol/L for 12 h, 24 h, 36 h and 48 h. Protein phosphatase 2A (PP2A) family inhibitor fostriecin (FST, 20 nmol/L) or okadaic acid (OA, 5 nmol/L) was selected to pretreat the HUVECs for 30 min. Protein phosphatase 4 catalytic subunit (PP4c) siRNA or protein phosphatase 2A catalytic subunit (PP2Ac) siRNA was transfected into the HUVECs. The protein expression levels of of eNOS, PP4c and PP2Ac, as well as the level of eNOS Ser633 phosphorylation, were detected by Western blot. The intracellular nitric oxide (NO) content was measured by DAF-FM DA. RESULTS(1) Compared with control group, the levels of eNOS Ser633 phosphorylation were decreased in PA groups in which the HUVECs were treated with 25 μmol/L, 50 μmol/L, 100 μmol/L and 200 μmol/L PA for 36 h (P<0.05) and 100 μmol/L PA for 24 h, 36 h and 48 h (P<0.05). No significant difference in the level of total eNOS protein expression among all the groups was observed. (2) Compared with control group, both FST and OA pretreatment reversed the reduction of eNOS Ser633 phosphorylation (P<0.05) and the decrease in intracellular NO content (P<0.05) induced by PA. No significant difference in the level of total eNOS protein expression among all the groups was observed. (3) Compared with si-Control group, the PP4c protein expression was significantly reduced (P<0.05), while the level of eNOS Ser633 phosphorylation was significantly increased in si-PP4c group (P<0.05). Although the levels of PP2Ac protein expression declined significantly (P<0.05), the level of eNOS Ser633 phosphorylation remained unchanged in si-PP2Ac group. No significant differencein the level of total eNOS protein expression among all the groups was found. CONCLUSION PA significantly reduces the level of eNOS Ser633 phosphorylation and the content of NO in the HUVECs, which may be due to PA inducing the activation of the PP2A family member PP4 rather than PP2A.     

Role of endoplasmic reticulum stress in trimethylamine N-oxide-induced oxidative stress in human umbilical vein endothelial cells

AIM: To investigate whether endoplasmic reticulum stress is involved in trimethylamine N-oxide (TMAO)-mediated oxidative stress in human umbilical vein endothelial cells (HUVECs). METHODS: The cell viability was examined by CCK-8 assay. The cells were stained by DCFH-DA, and the intracellular level of reactive oxygen species (ROS) was observed by phase-contrast microscopy and detected by flow cytometric analysis. The protein levels of phospho-IRE-1α, IRE-1α and GRP78/BiP were detected by Western blot. RESULTS: TMAO exerted no significant effect on the viability of HUVECs. For a long period (>24 h), even a low concentration (10 μmol/L) of TMAO increased the oxidative stress level in the HUVECs (P<0.05). TMAO increased the phosphorylation level of IRE-1α and significantly up-regulated the protein level of GRP78/BiP in HUVECs (P<0.01). Pretreatment with STF-083010, an inhibitor of IRE1α, for 1 h reduced TMAO-induced oxidative stress in HUVECs (P<0.05). CONCLUSION: Endoplasmic reticulum stress is involved in TMAO-induced oxidative stress in HUVECs.     

Effect of forsythiaside A on immune function in rats with ulcerative colitis

AIM To investigate the effect of forsythiaside A (FA) on immune function in rats with ulcerative colitis and its related mechanism. METHODS Healthy SD rats were randomly divided into 5 groups: control group (no treatment, normal feeding), model group (establishment of rat ulcerative colitis model), and low, medium and high doses of FA groups (treatment of the model rats with FA at 5 mg/kg, 20 mg/kg and 80 mg/kg, respectively). The malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in rat colon tissues were measured by colorimetry, and the serum levels of tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2) and IL-4 were detected by ELISA. The spleen index and thymus index, the percentages of CD3⁺, CD4⁺ and CD8⁺ T-lymphocytes in peripheral blood mononuclear cells （PBMC）, the serum IgA and IgG levels, and the serum complement C3 and C4 levels were also determined. RESULTS The colon tissues of the rats in model group showed obvious inflammation and ulceration, indicating that the animal model was successfully established. Compared with model group, the colonic inflammation and ulceration were significantly attenuated in FA groups, among which the high dose had the best effect. Compared with control group, the spleen index and thymus index of the rars in model group were decreased (P<0.05), MDA content in colon tissues was increased (P<0.05), and SOD activity in colon tissues was decreased (P<0.05). The levels of CD3⁺, CD4⁺, CD8⁺ and CD4⁺/CD8⁺ T-lymphocytes in PBMC, and the serum levels of C3, C4 and IL-4 were decreased (P<0.05), while the serum levels of IgA, IgG, TNF-α, and IL-2 were increased in model group as compared with control group. Furthermore, the spleen index and thymus index of the rats in FA groups were increased (P<0.05), the MDA content in the colon tissues was decreased (P<0.05), and the SOD activity in the colon tissues was increased (P<0.05). The levels of CD3⁺, CD4⁺, CD8⁺ and CD4⁺/CD8⁺ T-lymphocytes in PBMC, and the serum levels of C3, C4 and IL-4 were increased (P<0.05), while serum IgA, IgG, TNF-α and IL-2 levels were decreased in FA groups as compared with model group (P<0.05). CONCLUSION Forsythiaside A effectively attenuates the colonic lesions in rats with ulcerative colitis, and its mechanism may be related to reinforcement of oxygen free radical scavenging power, alleviation of inflammatory response, and enhancement of immune function.     

CD36/Src/ERK pathway is involved in process of monocyte differentiation into macrophages

AIM To investigate the role of fatty acid translocase (FAT/CD36) on differentiation of monocytes to macrophages. METHODS Human monocyte THP-1 cells were treated with phorbol 12-myristate 13-acetate (PMA) at 0, 100 and 200 μg /L. Small interfering RNA (siRNA) targeting CD36 (siCD36) was employed to knock down the expression of CD36 in THP-1 cells. The CD36 over-expression (CD36OE) cell line was constructed by transfection with a recombinant lentivirus containing CD36 cDNA. Optical microscopy and crystal violet staining were used to detect the monocyte morphological changes and adhesion ability. The protein expression of CD36 was measured by flow cytometry and Western blot. The mRNA levels of CD36, CD11b and CD80 were detected by real-time PCR. The protein levels of extracellular signal-regulated kinase (ERK） and Src tyrosine kinase were determined by Western blot. RESULTS The cellular adhesiveness of THP-1 cells was elevated in the process of monocytes differentiation, and the expression of CD36 was increased in this process as well (P<0.01). siCD36 was transfected into the THP-1 cells (CD36i group) and the silencing efficiency was approximately 80%. The cell surface area and cellular adhesiveness were significantly decreased in CD36i group compared with scrambled siRNA (NCi) group (P<0.01). The mRNA levels of CD11b and CD80 were decreased in CD36i group compared with NCi group (P<0.01). The cell surface area and cellular adhesiveness were increased in CD36OE group compared with empty vector (vector) group (P<0.05). The mRNA levels of CD11b and CD80 were increased in CD36OE group compared with vector group (P<0.01). The phosphorylation levels of ERK and Src were decreased in CD36i group compared with NCi group (P<0.05). CONCLUSION CD36 promotes the differentiation of human monocyte THP-1 cells to macrophages by increasing the phosphorylation of Src and further activating ERK.     

ROCK promotes high glucose-induced cardiomyocyte apoptosis by inhi-biting PI3K/Akt signaling pathway

AIMTo investigate whether Rho-associated coiled-coil kinase (ROCK) is involved in high glucose-induced apoptosis of primary cardiomyocytes by regulating PI3K/Akt signaling pathway. METHODSPrimary Wistar rat cardiomyocytes were cultured and identified by α-sarcomeric actin (α-SCA) immunohistochemistry. Cardiomyocytes were treated with 5.5, 33 and 40 mmol/L glucose for 48 h. The cell viability was measured by MTT assay, and the mRNA expression of ROCK1 and ROCK2 in the cardiomyocytes was detected by RT-qPCR. Flow cytometry was used to analyze the apoptosis of the cardiomyocytes. The protein levels of ROCK1, ROCK2, cleaved caspase-3, Bcl-2, PI3K, Akt and p-Akt were determined by Western blot. In order to confirm the regulatory effect of ROCKs on PI3K/Akt signaling pathway, the cells were divided into control group (5.5 mmol/L glucose), high glucose group (33 mmol/L glucose) and high glucose+Y27632 (ROCK inhibitor) group. Western blot was used to detect the protein levels of ROCK1, ROCK2, PI3K, Akt and p-Akt. RESULTSAfter 48 h of high glucose exposure, the values of relative cell viability in 33 and 40 mmol/L glucose groups were (79.71±2.43)% and (68.41±7.49)%, respectively, both of which were significantly decreased compared with normal control group (P<0.05). After 48 h of high glucose exposure, the relative mRNA levels of ROCK1 and ROCK2 in 33 and 40 mmol/L glucose groups were significantly increased compared with normal control group (P<0.05). Compared with normal control group, the apoptotic rate in 33 and 40 mmol/L glucose groups was increased significantly (P<0.05). Compared with normal control group, the protein expression of ROCK1, ROCK2 and cleaved caspase-3 in 33 and 40 mmol/L glucose groups was increased (P<0.05), while the protein expression of Bcl-2 was decreased (P<0.05). No significant difference in the protein levels of PI3K and Akt among the 3 groups was observed, while the protein level of p-Akt in 33 and 40 mmol/L glucose groups was decreased compared with normal control group (P<0.05). Compared with high glucose group, the expression of ROCK1 and ROCK2 was decreased in high glucose+Y27632 group. No significant difference in the protein levels of PI3K and Akt among the 3 groups was observed. Compared with normal control group, the protein level of p-Akt in high glucose group was decreased, and the protein level of p-Akt in high glucose+Y27632 group was increased significantly compared with high glucose group. CONCLUSION Under high glucose environment, ROCK may reduce the level of p-Akt by inhibiting the PI3K/Akt signaling pathway, thus promoting the apoptosis of cardiomyocytes.     

小冠开心形和细型主干形‘玉露香’梨光能截获与光合作用差异

小冠开心形和细型主干形是黄土高原梨树生产中的主要树形模式。为阐述这两种树形对冠层光能截获和叶片光合功能的影响,以山西芮城县4年生的‘玉露香’梨为试材,2017年和2018年连续两年测定了冠层截获的光合有效辐射PAR、叶片光合的光响应特性、荧光淬灭动力学特性以及光午休期间叶片的热耗散特性和光呼吸。结果表明：小冠开心形冠层不同方位和不同时刻截获的PAR均高于细型主干形,平均提高47.6%;与细型主干形相比,小冠开心形叶片光响应的最大净光合速率Pnmax,p与光饱和点LSP显著升高;光合碳同化过程的3个限制因子中,磷酸丙糖利用速率Vtpu对冠层光环境变化最敏感。正午强光胁迫下,小冠开心形叶片光呼吸速率Pr与总光合速率Pg的比例（Pr/Pg）比细型主干形叶片提高58.5%,NPQ中可恢复组分r(qE)提高了8.9%,而不可恢复组分r(qI)降低了75.0%。两种树形相比,小冠开心形梨树冠层可截获更多的光能,叶片的光合能力更强,强光胁迫时能够通过更高效的热耗散和光呼吸进行自我保护,可作为黄土高原产区梨树适宜树形。     

抗根肿病秋大白菜新品种‘CR京秋新3号’

大白菜‘CR京秋新3号’是由分子标记辅助饱和回交转育获得的抗根肿病的细胞质雄性不育系CMS84427CR和自交系832172CR配制而成的中晚熟一代杂种。生育期80 ~ 85 d,植株半直立,株高44 cm左右,开展度75 cm左右。外叶绿色,叶球直筒、叠抱,球高约34 cm,宽约18 cm,净菜质量约4 kg,净菜产量约90 t • hm-2。抗根肿病2号生理小种,抗病毒病、霜霉病。适合北方地区秋季种植。