黄蔷薇嫩枝扦插育苗技术试验研究

黄蔷薇嫩枝扦插育苗的成活率受很多因素的影响。通过试验研究表明,在以蛭石为扦插基质,用IAA、IBA、NAA处理插穗时,以IBA30mg/L,NAA20mg/L的浓度成活率较高,扦插后,加强扦插苗的水分、光照、温度、病害和施肥管理,可以进一步促进插穗的生根和生长。     

THE DISCUSSION ON THE MEASURES OF INCREASING NURSERY STOCK QUALITY IN FRIGID REGION OF CHINA

Through several years seedling-growing experiments in nursery in Daxing‘anMountains forest region,the author posed that the seedling cultivated for the region mustpossess the characteristics of being suited to thin and meager soil and having strongresistance to adverse conditions.For this purpose,the cultivation regime ought to bedirectization,standardization and programmatization;seedling growth ought to be promotedby regulating ecological conditions;and the mursery stock quality ought to be tested usingvigor index.     

5种木兰科树种育苗技术及苗木生长规律研究

木兰科中的金叶含笑、野含笑、木莲、毛桃木莲、观光木均为树形优美、树冠宽广、花大美丽的常绿乔木，对5个树种的种子主要参数及育苗方法进行了观测试验，对苗木物候、苗高生长规律进行初步研究，结果表明：5树种1年生苗根系发达．可出圃造林。其中毛桃木莲在国内尚无育苗技术及生产规律的研究报道。     

AutoCAD在苗圃规划设计中的应用

通过AutoCAD在苗圃规划设计中应用的实践,阐述了AutoCAD在苗圃规划设计中的使用方法,展示了其应用实例及效果,总结了AutoCAD应用在苗圃规划设计中提高绘图速度的方法,得出了AutoCAD在苗圃规划设计制图中有修改方案方便、定位精确度高、图面效果整洁统一、提高图纸绘制速度、总平面放样定位图一步到位的优点和着色力不强的缺点,并提供了相应的解决办法。     

深圳市横岗红棉路苗圃规划设计

以深圳市横岗红棉路闲置用地苗圃美化建设为例,从闲置用地概况、规划目标及指导思想、规划原则等几个方面进行探索,提出了闲置用地苗圃基地建设的具体规划方案,以期对同类型苗圃的规划设计起到借鉴作用。     

GCC技术在森林苗圃建设中的应用研究

文章介绍了GCC技术在森林苗圃建设中的应用,包括坐标定位、设计元素测算、图形解析等。     

不同基质对扶芳藤扦插育苗的影响

[目的]研究扶芳藤扦插育苗的最佳基质配比。[方法]采用5种基质配比,分别为M1(50%泥炭+50%珍珠岩)、M2(40%泥炭+60%珍珠岩)、M3(50%泥炭+50%栗钙土)、M4(40%泥炭+60%栗钙土)、M5(100%泥炭)对扶芳藤进行容器扦插育苗试验,对不同基质引起的扶芳藤愈伤率、生根率、根长、单株根系数目、新生枝数及新生枝生长量进行调查分析,[结果]结果表明,基质M1中扦插的扶芳藤生根率、愈伤率最高,分别为87%和88%;根长最长,为68.0 mm;平均新生枝数最多,为4.6条,效果最佳。基质M5中扦插的扶芳藤,其单株根系数目最少,为43.1条;新生枝生长量最高,为12.7 cm;基质M4最差。[结论]基质M1与M5比较适合扶芳藤插穗的生长。     

Dietary xylanase and live yeast supplementation influence intestinal bacterial populations and growth performance of piglets fed a sorghum-based diet

This study was to evaluate the effect of xylanase supplementation and the addition of live yeast, Saccharomyces cerevisiae, on growth performance and intestinal microbiota in piglets. One hundred and eighty commercial crossbred 23-d-old piglets (PIC 417) were sorted by initial BW and allocated to 3 treatments: control (CTR) diet, CTR diet supplemented with xylanase at 16,000 birch xylan units/kg (XYL) and XYL diet supplemented with live yeast (2 × 10¹⁰ CFU/g) at 1 kg/t (XYL + LY). Each treatment had 10 replicates, with 6 animals each. A sorghum-based diet and water were available ad libitum for 42 d of the study. Average daily gain (ADG) and average daily feed intake (ADFI) were measured from 0 to 42 d (23- to 65-d-old) and feed conversion ratio (FCR) calculated. At the end of the study, bacterial identification through 16S rRNA (V3 to V4) sequencing of the ileal and caecal digesta from one piglet per replicate was performed. No treatment effects were observed on ADFI. Pigs offered the live yeast in addition to the xylanase had increased ADG compared with those supplemented with xylanase alone (XYL + LY vs. XYL; P = 0.655). FCR was improved with XYL and XYL + LY compared with CTR (P = 0.018). Clostridiaceae counts in the ileum tended to reduce by 10% with XYL and 14% with XYL + LY compared to CTR (P = 0.07). XYL and XYL + LY increased the counts of Lactobacillaceae in the caecum compared with CTR (P < 0.0001). Dietary supplementation of live yeast combined with xylanase improved growth performance and microbial balance of piglets during the nursery phase.     

一例猪瘟混合感染副猪嗜血杆菌和猪蛔虫的案例诊治

2019年11月底,湖北某商品猪场保育猪只出现厌食、消瘦、呼吸困难、咳嗽等症状,偶有病猪急性死亡,为查找病因,控制疫情,减少损失,依次通过流行病学调查、病理剖检和实验室检测,最终确定该发病猪场为感染猪瘟病毒,进而继发感染Hps-4混合感染,并伴随蛔虫感染导致。通过筛选敏感药物治疗,优化生产管理,成功控制了此次疫情。该案例对此次疫情进行了分析总结,就加强生物安全建设,优化养殖管理,实现生产质量可控提供了参考建议。也为猪瘟混合感染呼吸系统细菌性疾病的防控提供参考。     

Intensive production of juvenile tiger shrimp Penaeus monodon: An evaluation of stocking density and artificial substrates

Tiger shrimp Penaeus monodon were intensively grown from PL₁₅ for 56 d in tank systems at stocking densities of 1000 and 2000 shrimp m^− 3, with and without the addition of artificial substrates (AquaMat® (buoyant and non-buoyant) and polyethylene mesh) at each density. Shrimp growth was significantly greater at the lower density and when substrates were added. Mean shrimp weight at harvest ranged from 0.64 ± 0.06 g (2000 shrimp m^− 3, no added substrate) to 1.17 ± 0.01 g (1000 shrimp m^− 3, added substrate). Survival was high and averaged 79.5 ± 2.7% across all treatments. The addition of substrates significantly increased survival at both stocking densities; however, survival was not significantly affected by stocking density. A maximum harvest density of 1645 shrimp m^− 3 and biomass of 1.27 kg m^− 3 were produced at a stocking density of 2000 m^− 3 with added substrates. Both harvest density and biomass significantly increased with stocking density and addition of substrates. The feed conversion ratio (FCR) of formulated feed was significantly lower when substrates were added. The results show that growth of P. monodon juveniles was inversely related to stocking density during intensive production. However, production output was significantly increased by addition of artificial substrates, which enhanced both growth and survival.