Synergistic effects of ginseng stem and leaf-extracted ginsenoside and choline on improving learning and memory in rats Association verification experiment in animals with multiple learning and memory disorders

BACKGROUND： Ginsenoside extracted from the stem and leaf of ginseng （GSL） and choline have both been shown to improve learning and memory functions; however, further studies are needed to understand the synergistic effects of a combination of both. OBJECTIVE： To verify the combined improved synergistic effects of GSL and choline on learning and memory disorders in rats. DESIGN： Control observation. SETTING： Taishan Medical College. MATERIALS： A total of 150 male Kunming mice weighing （204-2） g and 40 healthy male Wistar rats weighing （2204-20） g were provided by the Experimental Animal Department of Jilin University. Animal experimentation received confirmed consent from the local ethic committee. GSL was provided by the Department of Chemistry, Norman Bethune Medical University, and choline was provided by the Third Experiment Factory, Shanghai. METHODS： This study was performed at the Life Science Institute, Taishan Medical College from October 2006 to February 2007. ① Scopolamine-induced learning and memory disorders in rats： Forty rats were randomly divided into control group, model group, combination group （400 mg/kg GSL ＋ 200 mg/kg choline）, GSL （400 mg/kg） group, and choline （200 mg/kg） group, 8 rats/group. Rats were perfused and administrated in the morning, once a day for 14 successive days. Rats in the control group and model group were perfused with 20 mL/kg distilled water and underwent Morris water maze spatial resolution test 1 hour after perfusion on the 10m, 11m, and 12m days after administration. Rats also underwent passive step-down avoidance test 1 hour after reperfusion on the 13m and 14m days after administration. Thirty minutes prior to experimentation, rats in the remaining three groups were intraperitoneally （i.p） injected with 2 mg/kg scopolamine, and rats in the control group were i.p. injected with 2 mL/kg saline. ② Scopolamine-induced learning disorder and memory acquired disorder in mice： Fifty mice were randomly divided into control group, model group, combination group （400 mg/kg GSL ＋200 mg/kg choline）, GSL （400 mg/kg） group, and choline （200 mg/kg） group, with 10 mice/group. Mice were perfused and administrated in the morning, once a day for 9 successive days. Mice in the control group and model group were perfused with 20 mL/kg distilled water and underwent passive step down avoidance test 1 hour after reperfusion on the 8th and 9th day after administration. Twenty minutes prior to training, mice in the remaining three groups were i.p. injected with 2 mg/kg scopolamine, and mice in the control group were i.p. injected with 10 mL/kg saline. ③ Sodium nitrite-induced memory consolidation disorder in mice： Grouping, administration, and testing were the same as mentioned above. After training, mice in the remaining three groups were immediately subcutaneously injected with 120 mg/kg sodium nitrite, and mice in the control group were subcutaneously injected with 20 mL/kg saline. ④ Ethanol-induced memory reconsolidation disorder in mice： Grouping, administration, and testing were the same as mentioned above. At 24 hours after training and 20 minutes before retraining, mice in the remaining four groups were perfused with 10 mL/kg ethanol （0.3 volume fraction）, and mice in the control group were perfused with 10 mL/kg saline. MAIN OUTCOME MEASURES： Synergistic effects of GSL and choline on learning and memory deficits induced by scopolamine, sodium nitrite, and ethanol in experimental animals. RESULTS： All 40 rats and 150 mice were included in the final analysis. ① Synergistic effects of GSL and choline on learning and memory disorders induced by scopolamine in rats： During passive step-down avoidance and Morris water maze spatial resolution tests, the number of error responses and length of maze training in the model group were significantly greater than in the control group （P 〈 0.01）; while the number of error responses and length of maze training in the combination group were significantly less than in the model group, GSL group, and choline group （P 〈 0.05-0.01）. The Q value was 〉 1 after combining administration, which suggests that the combination of GSL and choline had synergistic effects. ② Synergistic effects of GSL and choline on learning disorder and memory-acquired disorder induced by scopolamine in mice： During passive step-down avoidance test, the number of error responses in the model group were significantly greater than in the control group （P 〈 0.01 ）; while the number of error responses in the combination group were significantly less than in the model group, GSL group, and choline group （P 〈 0.05-0.01）. The Q value was 〉 1 after combining administration, which suggests GSL and choline had synergistic effects. ③ Synergistic effects of GSL and choline on memory sodium nitrate-induced consolidation disorder in mice： During passive step down avoidance test, the number of error responses in the model group were significantly less than in the control group （P 〈 0.01 ）; while the number of error responses in the combination group were significantly less than in the model group, GSL group, and choline group （P 〈 0.05-0.01）. The Q value was 〉 1 after combined administration, which suggests GSL and choline had synergistic effects. ④ Synergistic effects of GSL and choline on ethanol-induced memory reconsolidation disorder in mice： During passive step down avoidance test, the number of error responses in the model group were significantly greater than in the control group （P 〈 0.01）; while the number of error responses in the combination group were significantly less than in the model group, GSL group, and choline group （P 〈 0.05-0.01）. The Q value was 〉 1 after combined administration, which suggests GSL and choline had synergistic effects. CONCLUSION： GSL and choline have synergistic effects on learning and memory functions.

Pretreatment with scutellaria baicalensis stem-leaf total flavonoid prevents cerebral ischemia-reperfusion injury

Pretreatment with scutellaria baicalensis stem-leaf total flavonoid has protective effects against ischemia and attenuates myocardial ischemia-reperfusion injury. In this study, rats were given scutellaria baicalensis stem-leaf total flavonoid intragastrically at 50, 100, and 200 mg/kg per day for 7 days before focal cerebral ischemia-reperfusion injury models were established using the suture method. We then determined the protective effects of scutellaria baicalensis stem-leaf total flavon- oid pretreatment on focal cerebral ischemia-reperfusion injury. Results showed that neurological deficit scores increased, infarct volumes enlarged, apoptosis increased and Bcl-2 and Bax protein expression were upregulated at 24 hours after reperfusion. Pretreatment with scutellaria baicalensis stem-leaf total flavonoid at any dose lowered the neurological deficit scores, reduced the infarct volume, prevented apoptosis in hippocampal cells, attenuated neuronal and blood-brain barrier damage and upregulated Bcl-2 protein expression but inhibited Bax protein expression. Doses of 100 and 200 mg/kg were the most efficacious. Our findings indicate that pretreatment with scutel- laria baicalensis stem-leaf total flavonoid at 100 and 200 mg/kg can improve the neurological func- tions and have preventive and protective roles after focal cerebral ischemia-reperfusion injury.

Pretreatment with scutellaria baicalensis stem-leaf total flavonoid protects against cerebral ischemia/reperfusion injury in hippocampal neurons

Previous experimental studies have shown that cerebral infarction can be effectively reduced following treatment with scutellaria baicalensis stem-leaf total flavonoid （SSTF）. However, the mechanism of action of SSTF as a preventive drug to treat cerebral infarction remains unclear. In this study, Sprague-Dawley rats were pretreated with 50, 100, 200 mg/kg SSTF via intragastric ad- ministration for 1 week prior to the establishment of focal cerebral ischemia/reperfusion injury. The results showed that pretreatment with SSTF effectively improved neurological function, reduced brain water content and the permeability of blood vessels, ameliorated ischemia-induced morphology changes in hippocampal microvessels, down-regulated Fas and FasL protein expression, elevated the activity of superoxide dismutase and glutathione peroxidase, and decreased malondialdehyde content. In contrast to low-dose SSTF pretreatment, the above changes were most obvious after pretreatment with moderateand high-doses of SSTF. Experimental findings indicate that SSTF pretreatment can exert protective effects on the brain against cerebral ischemia/reperfusion injury. The underlying mechanisms may involve reducing brain water content, increasing microvascular recanalization, inhibiting the apoptosis of hippocampal neurons, and attenuating free radical damage.

Scutellaria baicalensis stem-leaf total flavonoid reduces neuronal apoptosis induced by amyloid beta-peptide (25-35)

Scutellaria baicalensis stem-leaf total flavonoid might attenuate learning/memory impairment and neuronal loss in rats induced by amyloid beta-peptide. This study aimed to explore the effects of Scutellaria baicalensis stem-leaf total flavonoid on amyloid beta-peptide-induced neuronal apoptosis and the expression of apoptosis-related proteins in the rat hippocampus. Male Wistar rats were given intragastric administration of Scutellaria baicalensis stem-leaf total flavonoid, 50 or 100 mg/kg, once per day. On day 8 after administration, 10 pg amyloid beta-peptide （25-35） was injected into the bilateral hippocampus of rats to induce neuronal apoptosis. On day 20, hippocampal tissue was harvested and probed with the terminal deoxyribonucleotidyl transferase-mediated biotin-16-dUTP nick-end labeling assay. Scutellaria baicalensis stem-leaf total flavonoid at 50 and 100 mg/kg reduced neuronal apoptosis induced by amyloid beta-peptide （25-35） in the rat hippocampus. Immunohistochemistry and western blot assay revealed that expression of the pro-apoptotic protein Bax, cytochrome c and caspase-3 was significantly diminished by 50 and 100 mg/kg Scutellaria baicalensis stem-leaf total flavonoid, while expression of the anti-apoptotic protein Bcl-2 was increased. Moreover, 100 mg/kg Scutellana baicalensis stem-leaf total flavonoid had a more dramatic effect than the lower dosage. These experimental findings indicate that Scutellaria baicalensis stem-leaf total flavonoid dose-dependently attenuates neuronal apoptosis induced by amyloid beta-peptide in the hippocampus, and it might mediate this by regulating the expression of Bax, cytochrome c, caspase-3 and Bcl-2.

Study on the Relationship of Seedling Density and Line Spacing to Leaf-stem Ratio, DW/FW Ratio and Grass Yield of Forage Sweet Sorghum

[ Objectives ] The aim was to optimize the configuration of seedling density and line spacing of forage sweet sorghum （ Sorghum blcolor （ L. ） Moench） and explore its high-yield cultivation techniques. [ Methods] Effects of such two influencing factors as line spacing and seedling density on the leaf-stem ratio, DW/FW ratio and grass yield of forage sweet sorghum were analyzed by using split-plot experiment design experiment method and LSD method of IBM. SPSS. Statis- tics. v22 stati, stics software. [ Results ~ Seedling density and line spacing had no obvious effect on the leaf-stem ratio and DW/FW ratio of forage sweet sorghum but had obvious influences on the grass yield. Moreover, the optimal combination of seedling density and line spacing for high yield of forage sweet sorghum was A2 B4, that is, seedling density was 225 000 plants/hm2, and line spacing was 40 cm. [ Conclusions] The results provided a theoretical basis and technical support for high-yield cultivation techniques of forage sweet sorghum.

Antibacterial Activity of Psidium guajava Leaf and Stem Bark Extracts on Selected Bacteria in Ugbokolo, Benue State, Nigeria

Aim: In recent years, there has been a growing interest in researching and developing new antimicrobial agents from various sources to combat microbial resistance. The study was aimed at determining the phytochemical constituents and in vitro antibacterial activity of methanol and aqueous extracts of Psidium guajava leaves and stem bark on Escherichia coli, Salmonella typhi, Staphylococcus aureus and Proteus sp. in Ugbokolo, Nigeria. Materials and Methods: The phytochemical screening of the plant materials for various bioactive components was conducted between July and December, 2019 using standard laboratory techniques. The extracts were purified using column chromatography. The identity of the test isolates were confirmed using morphological characteristics, gram stain, motility and appropriate biochemical tests such as indole, catalase, coagulase, triple sugar iron agar. The susceptibility of the isolates to each bioactive component was determined using the agar well diffusion method. The broth dilution method was employed for the determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts. Results: The result of the study showed the presence of phenol, tannins, flavonoids and saponins as bioactive compounds. The antibacterial susceptibility of the isolates to aqueous and methanol extracts of leaf and stem bark of Psidium guajava varied significantly (P Staphylococcus aureus was the most susceptible isolate at 200 mg/ml concentration with average zone of inhibition of 13.05 mm for leaf extract and 15.34 mm for stem bark extract. Proteus sp. is the least susceptible with average zone of inhibition of 8.88 mm for the leaf extract and 12.36 mm for the stem bark extract respectively. Minimum Inhibitory Concentration and Minimum Bactericidal Concentration of aqueous and methanol extract of P. guajava leaf and stem bark showed that dilutions of various concentrations of aqueous and methanol extracts can inhibit and/or kill the isolates. Lower MIC (3.125 mg/ml) was shown by methanol extract than aqueous extract. MBC of methanol extract ranges between 6.25 - 25.0 mg/ml. Statistical analysis of the result showed methanol extract is more effective than aqueous extract while the stem bark of the plant showed higher efficacy than the leaf. Conclusion: The findings of the study imply that the extract of Psidium guajava has shown promising properties against tested microorganisms. Further study of the extract is therefore recommended.

Determination of the Photoperiod-Sensitive Inductive Phase in Maize with Leaf Numbers and Morphologies of Stem Apical Meristem

It is vital to determine the effective photoperiods of maize for making full use of tropical germplasm, which is the foundation for determining the effect of latitude and planting date on the development of photoperiod-sensitive maize cultivars. The objective of this study is to determine the photoperiod-sensitive inductive phase using reciprocal transfer between long- day （LD） （15 h d^-1） and short-day conditions （SD） （9 h d^-1）. For Huangzao 4 and CML288, days to tassel and pollen shedding were recorded, and stem apical meristems （SAM） were observed by a laser scanning confocal microscope. The results show that the seedlings are insensitive to photoperiod when they are very young （juvenile）. However, after this period, LD delays flowering and increases the leaf numbers below the inflorescence, and the length of the interval of the photoperiod-sensitive inductive phase is longer under LD conditions than under SD conditions. Transferred from SD to LD, plants show a sudden decrease in leaf numbers once sufficient SD has been received for flower commitment. While transferred from LD to SD, plants have a continuous increase in leaf numbers during the photoperiod sensitive inductive phase under LD conditions. At the same time, when plants are competent to flowers, the obvious morphology is the elongation of maize SAM. There is an obvious variance of the photoperiod sensitive phase under LD and SD conditions in different maize.

The Variety Screening of Green-stem Non-heading Chinese Cabbage and Dark-green-leaf Non-heading Chinese Cabbage Tolerant to Heat

[Objectives] Introducing and screening leaf vegetable varieties tolerant to heat and humidity has great significance to ensure balanced supply of vegetables in summer and autumn in Hainan Province. [Methods] On the basis of the introduction of green-stem non-heading Chinese cabbage and dark-green-leaf non-heading Chinese cabbage varieties, the varieties tolerant to heat and humidity were identified by the investigation of agronomic traits and evaluation of heat injury index. [Results] The data analysis results showed that four green-stem non-heading Chinese cabbage varieties including Huaguan Qingcaigeng F_1, Zhongguan Qinggeng, Hanshen No. 1 Qinggengcai F_1 and Huaxiawang Piaocai have the characteristics of strong tolerance to heat and high yield, and four dark-green-leaf non-heading Chinese cabbage varieties including Baimeigui, Heijingang, Xiaxue Naibaicai and Siji Baicai have the characteristics of strong tolerance to heat and high yield. [Conclusions] These eight leaf vegetable varieties are suitable for popularization in summer and autumn in Hainan Province.

Stem Population and Tissue Replacement of <i>Urochloa</i>in Different Phenological Stages

The objective of the present investigation was to evaluate the Urochloa Insurgent, Piata and Signal grasses by varying the phenology in the attributes: stem population dynamics, tissue replacement, leaf:stem relation and weight per stem. The data were analyzed using a completely randomized block design with arrangement in divided plots and four replications, the procedure used was PROC GLM from SAS. The Signal grass presented higher stem density with an average of 450 m?2 stems, while the meadow with Insurgent grass registered the lowest stem density throughout the investigation, with an average of 320 m-2 stems;furthermore, in this treatment, the stem density tended to increase slowly over time (P = 0.05). The Insurgente and signal grasses showed rapid leaf elongation from day 21 of regrowth with 123 and 104 cm stem?1, while in Piata the accelerated leaf elongation was on day 14 with 113 cm stem?1 where it remained active its growth until day 56 (P > 0.05). As the regrowth age was increasing, the population dynamics of stems and weight per stem were increasing;in Insurgent and signal the leaf elongation and net growth increased to a maximum point to start declining;however, in Piata grass was increasing without decreasing. The trend of the leaf:stem relation was decreasing as the test progressed and senescence increased from day 21 of regrowth.

Effect of Rhizobium Inoculation and Supplementation with Phosphorus and Potassium on Growth and Total Leaf Chlorophyll (Chl) Content of Bush Bean <i>Phaseolus vulgaris</i>, L.

The study was conducted to investigate the effect of Rhizobium inoculation and supplementation of phosphorus and potassium on growth and total leaf chlorophyll content to the three released bush bean varieties in northern Tanzania. To achieve this aim, the glasshouse experiment was conducted at Nelson Mandela African Institution of Science and Technology while field experiment were carried out at Tanzania Coffee Research Institute, in Kilimanjaro, Tanzania between April-July 2014. The experiment was laid out in factorial arrangement. Factor I comprised of three bush bean varieties. Factor II involved two inoculation treatments viz 1) inoculation with Rhizobium spp. and 2) without inoculation. Factor III included four fertilizer levels (0 Kg·ha-1 20 Kg K ha-1, 30 Kg P ha-1 and 20 kg·K + 30 Kg P ha-1). Both screen house and field experiments were replicated four times. Plant growth parameters (plant height (cm), number leaves per plant, stem girth (mm)) were measured at 2, 4 and 6 weaks after planting (WAP). The chlorophyll was extracted by using Dimethylsulphoxide (DMSO) and absorbance was determined at 645 and 663nm using UV/Visible spectrophotometer. Results showed that Rhizobium application significantly improved the number of leaves per plant, plant height, pant girth and total leaf chlorophyll content. Furthermore, compared with the zero treatment control, potassium fertilization significantly increased the number of leaves per plant, plant height, pant girth and total leaf chlorophyll content of the three varieties. In general, these parameters were significantly increased with phosphorus supplied at 30 kg/ha. The combination of these supplies at different levels resulted in significant interactions in some parameters and thus indicating need for these inputs in the study area.

鱼腥草叶斑病及茎斑病病原菌的分离与鉴定

为了明确引起四川省广汉市鱼腥草新型叶斑及茎斑类病害的病原菌种类,为该病的科学防治提供理论依据,对采自广汉市的鱼腥草病茎叶通过组织消毒分离、离体接种、形态学观察与基于核糖体转录间隔区(ITS)、延长因子(tef1)、钙调蛋白(cal)和组蛋白(his3)基因的分子鉴定进行病原菌的分离鉴定。结果表明,病原菌菌丝呈灰白色到浅褐色,其分生孢子器可产生纺锤形到椭圆形的α型分生孢子以及丝状或钩状β型分生孢子。多基因联合系统发育分析表明,病原菌在大豆间座壳(Diaporthe sojae)和菜豆间座壳(D.phaseolorum)分枝外单独聚为一枝,并且3枝一起聚为一个大枝,因此建议成立一个新种—鱼腥草间座壳(D.houttuynia)来容纳此类病菌。结合形态学和分子鉴定结果,将引起广汉市鱼腥草新型叶斑及茎斑类病害的病原菌鉴定为鱼腥草间座壳(D.houttuynia)。

银州柴胡茎叶的发育解剖学研究

以伞形科柴胡属植物银州柴胡(Bupleurum yinchowense)为研究对象,采用石蜡切片结合组织透明法对银州柴胡茎和叶的结构发育进行研究,以期为柴胡属植物的分类和鉴定提供科学依据。结果显示,银州柴胡茎的发育可分为原分生组织、初生分生组织、初生生长以及次生生长4个阶段,茎尖顶端分生组织分为原套和原体;茎的初生分生组织包括原表皮、基本分生组织和原形成层,原表皮发育为表皮,基本分生组织发育为皮层、髓射线和髓,原形成层发育为维管束(由初生韧皮部、形成层和初生木质部组成);茎的初生结构包括表皮、皮层和维管柱,维管柱包括维管束、髓射线和髓;银州柴胡茎有微弱的次生生长,髓射线位置细胞的细胞壁常明显加厚。叶的发育分为原分生组织、初生分生组织和初生生长3个阶段;叶为异面叶,上下表皮由一层细胞组成,有气孔分布,为无规则型;栅栏组织由1层细胞组成,海绵组织由6~8层细胞组成;叶脉维管束为外韧维管束,其上下方均未观察到纤维分布;茎棱角的皮层、初生韧皮部、髓周围以及叶脉韧皮部均分布有分泌道;叶脉维管束木质部上方的组织中,分泌道有或无;银州柴胡茎和叶分泌道均为裂生型。结果表明,银州柴胡茎和叶的结构特点明显,有别于其他柴胡属植物,可为柴胡属药用植物的分类和鉴定提供科学依据。

黄芪茎叶提取物对仔猪生长性能、养分表观消化率及免疫指标的影响

文章旨在探究添加不同水平黄芪茎叶提取物对断奶仔猪生长性能、养分表观消化率及免疫机能的影响。试验将120头健康的体重(25±0.5)kg的“杜×长×大”三元杂交仔猪随机分成4组,每组3个重复,每个重复组10头,试验分别在基础日粮中添加0(1组)、1.0%(2组)、1.5%(3组)、2.0%(4组)黄芪茎叶提取物,预饲期10d,整个试验为期56d。结果表明:(1)试验3、4组平均日增重较1组分别显著提高11.6%、10.1%(P <0.05),其料重比较1组分别显著降低9.4%、7.0%(P <0.05);(2)试验3、4组粪便中的粗蛋白质、粗脂肪、粗纤维的养分表观消化率较1组分别显著提高10.9%、10.8%、10.8%、11.2%、16.5%、15.9%(P <0.05);(3)试验3、4组血清中IgA、IgG、IL-2含量较1组分别显著提高10.8%、11.7%、12.0%、13.7%、22.9%、25.1%(P <0.05),其血清中TNF-α含量较1组分别显著降低20.8%、22.1%(P <0.05)。综上所述,添加1.5%黄芪茎叶提取物可以提高“杜×长×大”二元杂交仔猪的生长性能、养分表观消化率及免疫机能。

不同微生物添加剂对辣木茎叶青贮感官评价、营养成分及发酵品质的影响

试验旨在研究不同微生物添加剂对辣木茎叶青贮感官评价、营养成分及发酵品质的影响。试验以辣木茎叶为底物,对照组中不添加微生物制剂,试验组分别添加植物乳杆菌(A组)、酵母菌(B组)、枯草芽孢杆菌(C组)、植物乳杆菌+酵母菌(D组)、酵母菌+枯草芽孢杆菌(E组)、植物乳杆菌+枯草芽孢杆菌(F组)、植物乳杆菌+酵母菌+枯草芽孢杆菌(G组),每组3个重复,青贮30 d,测定辣木茎叶青贮的感官、营养成分及发酵品质。结果显示:对照组辣木茎叶青贮感官评价分数最低,为12分,D组、E组、F组、G组辣木茎叶青贮得分为18~19分,等级为一级优良。与对照组比较,除A组外,其余微生物添加剂组辣木茎叶青贮的粗蛋白(CP)含量均显著升高(P<0.05),D组、E组、F组和G组中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量显著降低(P<0.05),所有微生物添加剂组木质素(ADL)含量均显著降低,相对饲喂价值(RFV)显著升高(P<0.05)。与对照组比较,所有微生物添加剂组辣木茎叶青贮的pH值均显著低于对照组(P<0.05),且低于4.2,D组、E组、F组和G组青贮饲料的氨态氮(NH3-N)含量显著降低(P<0.05),所有微生物添加剂组辣木茎叶青贮的乳酸(LA)含量均显著升高(P<0.05);所有微生物制剂组辣木茎叶青贮中的植酸含量均显著降低(P<0.05)。研究表明,辣木茎叶青贮过程中添加植物乳杆菌、酵母菌及枯草芽孢杆菌均可不同程度地改善感官评分、营养品质及发酵品质,且以植物乳杆菌+酵母菌+枯草芽孢杆菌组效果最好。

Effect of Leafy and Leafless Greenwood, Softwood and Hardwood Cuttings Success of <i>Garcinia kola</i>(Heckel)

Garcinia kola Heckel, called “petit cola” in Côte d’Ivoire and “bitter kola” in Nigeria, is a Non-Timber Forest Product of great socioeconomic importance. Unfortunately, this species is threatened due to overexploitation and deforestation. This study tested the effect of leaf area on stem cuttings to regenerate vegetatively in a non-mist poly-propagator without using exogenous hormones. Three stem cuttings types: greenwood, softwood and hardwood (12 - 15 cm in length) were collected from 24-month years old seedlings. The two top leaves of each cutting type were conserved at different leaf area: 0 cm2, 28.25 cm2, 56.5 cm2, 84.75 cm2 and 113 cm2 (entire leaf area). Observations were made on rooting, sprouting and leafing abilities of cuttings depending to treatments applied. Results showed that all cutting types have presented good ability to shooting and rooting. Cuttings with 113 cm2 leaf areas presented the best rooting (94.44% ± 2.42%) and shouting (95.55% ± 2.42%) percentage and longest primary root length (12.03 ± 0.50 cm). Hardwood, softwood and greenwood cuttings with 113 cm2 leaf area had the best rooting percentage (96.66% ± 3.33%, 96.66% ± 5.77% and 90.00% ± 5.77% respectively). The longest primary root length (13.50 ± 0.97 cm) was observed to greenwood cuttings with 113 cm2 leaf area. Regenerated plants in the forest presented well survival percentage (96.66%). This study shows that it is possible to regenerate entire plants by cuttings without using external hormones in non-mist poly-propagator.

西番莲茎叶提取物对热应激下蛋鸡产蛋性能、蛋品质和抗氧化性能的影响研究

试验旨在了解西番莲茎叶提取物对夏季热应激下蛋鸡产蛋性能、蛋品质和抗氧化性能的影响。试验于夏季选取210日龄海兰褐蛋鸡240只,随机分为对照组、低剂量组、中剂量组和高剂量组4组,对照组饲喂基础日粮,低、中、高剂量组分别在基础日粮中添加250、500、1000 mg/kg的西番莲茎叶提取物,试验期42 d。结果显示,低、中、高剂量组蛋重均显著高于对照组(P<0.05),高剂量组产蛋率显著高于对照组(P<0.05),高、中剂量组平均日采食量显著高于对照组(P<0.05),高剂量组料蛋比显著低于对照组(P<0.05)。高、中剂量组鸡蛋的蛋白高度和哈夫单位显著高于对照组(P<0.05),高剂量组鸡蛋的蛋壳厚度显著高于对照组(P<0.05);各组蛋黄重、蛋黄比例、蛋形指数和蛋黄颜色无显著差异(P>0.05)。高、中剂量组血清中谷胱甘肽过氧化物酶活性显著高于对照组(P<0.05);低、中、高剂量组血清中丙二醛(MDA)含量显著低于对照组(P<0.05);各组间血清中超氧化物歧化酶、总抗氧化能力和过氧化氢酶活性差异不显著(P>0.05)。说明西番莲茎叶提取物可提高夏季热应激条件下海兰褐蛋鸡产蛋性能、蛋品质和抗氧化性能。

机器学习结合高光谱植被指数与SPAD值估算冬小麦氮含量

冬小麦叶片氮含量与叶片光合作用和营养状况密切相关,直接影响植株生长发育,而茎秆中的氮含量与茎秆中纤维素、半纤维素和木质素的比例和含量密切相关,直接影响茎秆质量及植株的抗倒伏能力。然而,有关对冬小麦茎秆氮含量估算研究较为有限,限制了从氮含量角度判断茎秆质量及对倒伏的预测能力。为精准估算冬小麦不同器官(叶片、茎秆)氮含量,该研究通过2年田间试验,获取冬小麦4个关键生育期(拔节期、抽穗期、开花期、灌浆期)和3种施氮水平条件下(N1、N2和N3)的冠层光谱反射率、叶片、茎秆氮含量及叶片SPAD(soil and plant analyzer development,SPAD)值。分析了不同生育期和施氮水平条件下高光谱植被指数对叶片和茎秆氮含量的敏感性,并结合5种常用的机器学习算法:随机森林回归(random forest regression,RFR)、支持向量回归(support vector regression,SVR)、偏最小二乘回归(partial least squares regression,PLSR)、高斯过程回归(gaussian process regression,GPR)、深度神经网络回归(deep neural networks,DNN)构建冬小麦叶片和茎秆氮含量估算模型。结果表明:高光谱植被指数对叶片和茎秆氮含量的敏感性受到生育期和施氮水平的影响。在灌浆期,最佳植被指数双峰冠层植被指数DCNI(double-peak canopy nitrogen index)对叶片氮含量的敏感性最高,R^(2)为0.866。对茎秆氮含量,在抽穗期的敏感性最高,最佳植被指数归一化叶绿素比值指数NPQI(normalized phaeophytinization index)与氮含量决定系数R^(2)=0.677。施氮水平的提升增加了光谱植被指数对茎秆氮含量的敏感性。结合SPAD值的机器学习算法提升了氮含量的估算精度,对叶片氮含量,在不同生育期和施氮水平条件下估算精度提升了1%~7%,其中在全生育期的归一化均方根误差NRMSE从0.254降低到0.214,抽穗期的NRMSE提升最大,从0.201降低到0.128。对茎秆氮含量,全生育期的NRMSE从0.443降低到0.400,抽穗期的NRMSE变化最大,从0.323降低到0.268。在全生育期,结合SPAD值的DNN模型对叶片(R^(2)=0.782、NRMSE=0.214)和茎秆(R^(2)=0.802、NRMSE=0.400)氮含量的估算精度最佳。研究说明,SPAD值与光谱植被指数结合有利于提升冬小麦不同生育期和施氮水平条件下叶片和茎秆氮含量的估算精度。

590份燕麦种质资源营养器官表型性状遗传多样性分析

为明确燕麦(Avena sativa)种质资源营养器官表型性状的遗传多样性和各性状之间的相关关系,进而为燕麦育种和种质资源创新利用提供理论依据,本研究以国内外收集的590份燕麦种质资源为研究对象,在青海省西宁市湟中区对其从地上器官质量性状、茎部性状、叶部性状和分蘖性状的遗传多样性进行评价分析,并利用相关性分析和聚类分析方法,评价其营养器官表型性状的遗传变异水平。结果表明:590份燕麦种质资源质量性状遗传多样性指数以茎节绒毛最高(1.026),苗期株型最低(0.162);数量性状的遗传多样性指数以第三茎节茎粗最高(2.09),旗叶叶面积最低(1.87);变异系数以无效分蘖数(54.92%)最大,茎节数最小(12.20%);茎部性状和倒二叶长、倒二叶叶面积是影响燕麦种子和饲草产量的重要因子。590份燕麦资源可分为4大类群,其中类群Ⅲ可作为饲草型育种目标的亲本材料,类群IV可作为抗倒伏育种材料。

马铃薯茎叶还田对土壤理化性质及细菌群落结构的影响

【目的】探究马铃薯茎叶还田对土壤理化性质和细菌群落结构的影响。【方法】基于土壤理化分析和Illumina高通量测序技术,对比分析马铃薯茎叶还田(处理组R)与不还田(处理组NR)土壤理化指标和细菌群落结构的差异。【结果】与处理CK相比,马铃薯茎叶还田提高土壤pH及有机质、碱解氮、有效磷、速效钾含量,其中速效钾含量增幅最大,达42.36~141.53 mg/kg。马铃薯茎叶还田显著影响土壤细菌群落结构,在第45、90天时,还田处理土壤中12个细菌类群丰度显著提高,且还田处理较不还田处理土壤细菌群落的物种多样性显著提高。各处理土壤细菌群落的种间互作关系主要发生在酸杆菌门、放线菌门(Actinobacteriota)和变形菌门,且马铃薯茎叶还田处理较不还田处理,土壤细菌群落种间互作强度显著提高。相关性分析表明,Latescibacterota、脱硫菌门(Desulfobacterota)与有效磷含量呈极显著负相关,与碱解氮、有机质含量呈显著正相关;粘球菌门(Myxococcota)、Bdellovibrion⁃ota、髌骨菌门(Patescibacteria)、肠杆菌门(Entotheonellaeota)、芽单胞菌门(Gemmatimonadota)、硝化螺旋菌门(Nitrospirota)、变形菌门(Proteobacteria)与速效钾含量呈显著正相关。【结论】马铃薯茎叶还田处理可以提高土壤养分含量,显著提高土壤细菌群落的物种多样性及群落物种互作强度,土壤速效钾、有效磷、碱解氮及有机质含量等理化指标与土壤细菌群落物种组成存在显著的相关关系。

茎段和穴盘大小对北方叶用甘薯越冬育苗的影响

为探索北方叶用甘薯越冬穴盘育苗,设置4个茎段大小(4、6、8、10 cm,用D1、D2、D3、D4表示)和5种穴盘规格(32、50、72、105、128孔),搭配14个处理,研究不同搭配对种苗成活率、幼苗长势(茎粗、株高等)和鲜重等指标的影响。结果表明:相同穴盘下,随着茎段增长,幼苗的成活率、叶片数、基部茎粗和株高呈现增加的趋势,进而地上部鲜重和整株鲜重也随之增加,以D4处理最高。相同茎段下,随着穴盘孔数增加,幼苗的叶片数、基部茎粗、株高、地上部鲜重和全株鲜重减少,源于穴盘对地下部的影响,以32孔处理最高。不同茎段和穴盘搭配下,D4-32处理的生长情况最好,3月中旬,对于地上部鲜重而言,D2-72处理(9.79 g)可达到与D4-32处理相同的效果(两者间无显著性差异),其叶片数、基部茎粗和株高等指标满足移栽水平;对于整株鲜重而言,D2-105处理(10.21 g)可达到与D4-32处理相同的效果,且可节省228.1%的育苗面积,参考其重量,1月中旬,D3-72处理下的地上部和整株鲜重接近上述两个处理的水平,可节省125.0%的育苗面积。综合秧苗生长情况与经济效益,3月中旬移栽时,推荐D2-105,即含2个腋芽茎段与105孔穴盘的搭配,如有生产条件在1月中旬移栽,推荐D3-72,即含3个腋芽茎段与72孔穴盘的搭配。