江苏仪征低丘岗地营林开发模式优化选择研究

总结江苏省仪征低丘岗地开发的经济林、用材林等7种营林模式和5种纯板栗与农作物间作模式，评估其生产和经济效益，优化选择出了板栗与茶复合林模式、纯梨园、纯茶园、纯桃园等4种开发营林模式；板栗与山芋 雪菜、板栗与芝麻 胡罗卜、板栗与花生 苕子等3种板栗与农作物间模式。其中板栗与茶，并期板栗与山芋 雪菜等间作模式，可形成高效复合经营开发模式。文内还提出了该市低丘岗地综合治理与开发试点试区的建设原则，发展模式及应实施的集约组装技术。     

山杨复合胶合板的制作

本文描述了利用山杨材制和复合胶合板的研究，研究结果表明，以其优质材料旋切的单板为表层材料，以劣质木材制作的刨花板为芯层材料制作和复合胶合板的主要物理力学性能指标与传统的胶合板板基本相同。     

紫花苜蓿人工草地施肥试验

在辽宁西部坡地上进行紫花苜蓿不同施肥处理试验，经过1年的研究结果表明，在苜蓿人工草地上无论是单一施用氮肥还是复合肥，均可有效地提高牧草产量并取得较为明显的经济效益，其中以每亩施用尿素15 kg和25 kg效果最好，效益最高，每亩可增经济效益分别是40.74元和40.63元。     

Study on Liver-protective Effect of Chinese Herbal Compound Probiotics on Acute Liver Injury Layers

This experiment was conducted to investigate the liver-protective effect of Chinese herbal compound probiotics (CHCP) on acute liver injury layers.One hundred and eight 1 day old hens were divided into 4 groups with 3 replicates in each group and 9 layers per replicate in trial 1.The layers in model groups Ⅰ to Ⅲ were gavaged with 10% (V/V) soybean oil solution of carbon tetrachloride (SCCl₄) according to 1,2 and 4 mL/(kg·BW) at 14,28 and 35 d,respectively.The layers in control group were gavaged with 2 mL/(kg·BW) soybean oil.In trial 2,sixty 1 d layers were divided into 5 groups:Control group (soybean oil),model control group(SCCl₄)and low-dose,middle-dose and high-dose CHCP group (SCCl₄+1‰ CHCP,SCCl₄+2‰ CHCP and SCCl₄+4‰ CHCP respectively).CHCP were used by drinking water since 7 days.SCCl₄ were gavaged according to 2 mL/(kg·BW) at 14 and 28 d.The results showed as follows:The model of layers liver damage could be built by intragastric administration of 2 mL/(kg·BW) 10%(V/V) SCCl₄ at 14,28 d respectively,with the signs of hepatic steatosis,severe vacuolar degeneration,nuclear condensation and necrosis.Compared to the model control group,the serum AST levels in low,medium and high dose CHCP groups were decreased by 4.35% (P > 0.05),7.57% (P > 0.05) and 9.79% (P < 0.05),the serum ALT levels in medium and high dose CHCP groups were decreased by 34.92% (P < 0.01),36.51% (P < 0.01),the serum total bilirubin content in medium and high dose CHCP groups were decreased by 25.49% (P < 0.01),27.45% (P < 0.01).The liver cell congestion was reduced to varying degrees in different dose CHCP groups,and the liver cell had no vacuoles,arranged in neat rows,abundant cytoplasm and uniform in different dose CHCP groups.In conclusion,2‰,4‰ CHCP could reduce hepatocyte necrosis,decrease the serum activities of ALT,AST and total bilirubin levels,and had protective effect on hepatic injury induced by SCCl₄.     

Improvement of growth performance,water quality and disease resistance against Vibrio harveyi of postlarval whiteleg shrimp (Litopenaeus vannamei) by administration of mixed microencapsulated Bacillus probiotics

The objective of this study was to investigate the effects of mixed Bacillus on growth, water quality and disease resistance against Vibrio harveyi in whiteleg shrimp (Litopenaeus vannamei). Postlarval shrimp (PL₃₀) were fed with (a) a basal diet (the control), (b) a diet containing mixed freeze‐dried Bacillus probiotics (FB) and (c) addition of mixed microencapsulated Bacillus probiotics (MB) in culture water. Addition of FB and MB probiotics improved (p < .05) growth, feed efficiency, survival and culture water quality (ammonia and nitrite) compared to the control group although there was no difference (p > .05) between the two treated groups. Bacillus numbers in gastrointestinal tracts and culture water of FB‐ and MB‐administrated shrimp were higher (p < .05) than in the control. After a 30‐day culture, shrimp were infected with V. harveyi and monitored for 10 days. A significant reduction (p < .05) in cumulative mortality was observed in FB‐ and MB‐supplemented shrimp (43.24% and 45.05%, respectively), compared to the control (63.06%). This finding demonstrated that administration of microencapsulated probiotics was as effective as freeze‐dried probiotics for improving growth, feed efficiency, survival, Bacillus in gastrointestinal tracts, water quality (ammonia and nitrite) and conferring disease resistance to V. harveyi.     

Effects of fish origin probiotics on growth performance,immune response and intestinal health of shrimp (Litopenaeus vannamei) fed diets with fish meal partially replaced by soybean meal

This study was conducted to evaluate the application of four fish origin probiotics to relieve the side effects induced by SBM in shrimp. Shrimps were fed with high fish meal diet (C0, positive control containing 500 g/kg FM and 0 g/kg SBM), low fish meal diet (C, control containing 250 g/kg FM and 340 g/kg SBM) or the control diet (C) supplemented, respectively, with 1.0 × 10⁸ CFU/g Bacillus pumilus SE5 (T1), Psychrobacter sp. SE6 (T2), Enterococcus faecium MM4 (T3) or Bacillus claussi DE5 (T4). After 6 weeks of feeding, the growth performance, hepatopancreatic digestive enzymes, intestinal histological structure and immune parameters were determined. The results showed that compared with high FM group (C0), significantly lower WGR and SGR as well as higher FCR were observed in the low FM group (C) (p < .05). Compared with the control, significantly lower FCR was observed in treatment T1 (p < .05), but not in treatments T2–T4. Protease, amylase and lipase activities in all the treatments (T1‐T4) were significantly higher than the control (p < .05). GOT and GPT activities in the control were significantly lower than the C0 (p < .05), while higher MDA level was recorded in the control (p < .05). Meanwhile, higher GPT activities were observed in treatments T1‐T4 compared with the control (p < .05). Compared with the C0, lower SOD, ACP and AKP activities were observed in the control. Significantly improved SOD and AKP activities were observed in all probiotic feeding groups compared with the control (p < .05). The control diet led to significant reduction of intestinal wall thickness and villus height compared with the C0 (p < .05), while significantly higher intestinal wall thickness and villus height were exhibited in all the probiotic groups compared with the control (p < .05), except intestinal wall thickness in treatment T3. Thus, these results demonstrated that the four fish origin probiotic strains could relieve the side effects induced by high level of SBM in shrimp, while probiotic B. pumilus SE5 showed the best performance.     

Biocontrol of saprolegniosis in rainbow trout (Oncorhynchus mykiss Walbaum) using two bacterial isolates (LE89 and LE141) of Pseudomonas fluorescens

The probiotic activity of 15 bacterial isolates that inhibit Saprolegnia parasitica in vitro was tested for the biocontrol of saprolegniosis in rainbow trout (Oncorhynchus mykiss Walbaum), adding the bacteria to tank water for 14 days at a concentration of 10⁶ bacteria ml^?1 water. Pseudomonas fluorescens LE89 and Pseudomonas fluorescens LE141 were effective in controlling experimental infection with S. parasitica since of the fish treated with LE89, 24.5% ± 16.27% (p < 0.05) became infected, as did 42.8% ± 8.41% (p < 0.05) of those treated with LE141. Given their protective effect when administered in water, their effect was also studied when administered in feed before and after experimental infection. Both bacterial isolates survived low pH levels and the action of bile, grew in skin and intestinal mucus, were resistant to several antibiotics and survived in feed; however, neither of the two isolates prevented S. parasitica infection when administered in feed.     

有机生态栽培基质配比对生菜生长及品质的影响

以传统基质草炭、蛭石及腐熟羊粪和玉米秸秆为原料,配制成12种不同配比的栽培基质,以商品叶菜类栽培基质作为对照,研究不同基质配方对生菜生长的影响,以期获得最适合生菜栽培的基质配比组合。结果表明,不同组合基质配比均能满足生菜的正常生长,所有处理的株高、叶面积、单株鲜重和单株干重都较对照组(CK)有着不同程度提高,其中T11(草炭∶腐熟羊粪∶玉米秸秆∶蛭石=1∶4∶3∶4)条件下各指标表现最好,分别较CK提高了31.80%、47.15%、59.43%和79.53%;从生理生化指标来看,T11处理的Vc含量最高,是CK的2.5倍;T10(草炭∶腐熟羊粪∶玉米秸秆∶蛭石=3∶1∶4∶4)的根系活力是所有处理中最高的,达到CK的2.02倍;T12(草炭∶腐熟羊粪∶玉米秸秆∶蛭石=3∶4∶1∶4)处理的叶绿素含量最高,是CK的1.41倍,硝酸盐含量最低,较CK降幅达到74.59%。通过隶属函数进行综合比较分析,我们认为T11是所有供试处理中最适合生菜栽培的基质配比。     

改性尿素硝酸铵溶液调控氮素挥发和淋溶的研究

为了提高肥料的利用率,以尿素硝酸铵溶液为原料、聚氨酸为保护剂,复合抑制剂NBPT(N-丁基硫代磷酰三胺)和DMPP(3,4-二甲基吡唑磷酸盐)为材料,开发出改性尿素硝酸铵溶液(YUL1和YUL2),研究其对华北平原夏玉米追肥过程中的氨挥发和淋溶损失的调控效果。田间试验设置6个处理:不施氮肥(CK)、农民习惯追施尿素(CN)、优化追施尿素(CNU)、优化追施尿素硝酸铵溶液(UAN)、优化追施改性尿素硝酸铵溶液(YUL1)和优化追施改性尿素硝酸铵溶液(YUL2)。采用扫描电镜和能谱仪分析相关指标变化,在夏玉米喇叭口期追施氮肥后15d内进行田间原位连续动态观测氨挥发和土壤铵态氮和硝态氮变化,并在玉米成熟期测定产量,计算经济效益。结果表明,改性尿素硝酸铵溶液清澈无杂质,流延后成膜表面光滑、致密,抑制剂在膜表面分布均匀;能谱测试膜层表面磷硫含量增高,证明复合抑制剂与尿素硝酸铵溶液达到有效融合。在同等优化施氮量下:与CNU相比, YUL1氨挥发总量显著降低19.3%, YUL2增加9.6%;与UAN相比, YUL1、YUL2分别显著降低57.3%和42.0%。与其他施氮处理相比, YUL1和YUL2夏玉米季生长中后期0～20 cm土层依然保持相对较高的氮素含量水平,夏玉米收获后土壤硝态氮含量分别比CNU高46.0%和43.4%,比UAN高45.6%和44.7%;180～200cm土层硝态氮含量显著低于其他处理。在保证产量和净收益的同时,改性尿素硝酸铵肥料显著降低了氮素的氨挥发和淋溶损失浓度,尿酶抑制剂含量相对较高的YUL1抑制氨挥发的效果更好,硝化抑制剂含量相对高的YUL2硝态氮向下淋失的风险更小。     

东北“三大硬阔”叶片和叶轴质量分配比较

以3个树种健康复叶为试材,研究了叶内光合构件和支撑构件的生物量投资的种内种间变化规律。结果表明:水曲柳、胡桃楸和黄檗叶轴质量占复叶质量的比例分别为0.18、0.26和0.17,胡桃楸显著大于其它2个树种。跨物种尺度上,复叶大的树种需要更多的叶内支撑结构投资。但物种水平上,水曲柳叶片投资随叶增大而增大,胡桃楸则降低,黄檗基本稳定,表现出与跨物种水平上的叶片投资随叶增大而降低的普遍规律不同。今后需要加深物种水平上叶内生物量分配的异速生长的了解。