Seasonal changes in carbohydrate storage and regrowth in rhizomes and stems of four boreal forest shrubs: Applications in picea glauca understorey regeneration

Understorey scarification methods are used to enhance regeneration of Picea glauca; however, understorey shrubs have been identified as major competitors for regenerating tree species. To investigate the resprouting potential of rhizomes of four boreal forest shrub species in the understorey, rhizome segments (30, 15, and 10 cm in length) of Corylus cornuta, Cornus stolonifera, Rosa acicularis, and Viburnum edule were planted in five boreal mixed‐wood sites in northern Alberta at four times during the 1994 growing season. Sugar and starch concentrations in rhizome and stem pieces of these shrubs and Epilobium angustifolium were determined for each date. The segments and their regrowth were excavated in the autumn of 1995. Rhizome length had no effect on regrowth but there was a marked increase in regrowth for segments planted late in the growing season. The cryptophyte, E. angustifoUum, accumulated large amounts of carbohydrates during the growing season, i.e. 28% of dry weight compared with 6–14% of dry weight for the phanerophytic shrubs. All four shrubs had lowest regrowth when total non‐structural carbohydrate concentrations were at their lowest levels.     

低影响开发与绿色雨水基础设施的植物选择与设计

目的研究5种热带花灌木在不同水分胁迫处理下生理及形态指标的变化,以揭示植物对旱涝胁迫的响应规律。方法以黄蝉(Allemanda schottii)、栀子(Gardenia jasminoides)、斑叶鹅掌藤(Schefflera arboricola ‘Variegata’)、钟花蒲桃(Syzygium campanulatum)和狗牙花(Tabernaemontana divaricata) 5种热带花灌木为试验材料,对其进行正常供水(CK)、干旱(CD)、水淹(CF)、旱涝交替(FD) 4个水分胁迫处理,观察不同水分胁迫处理下植物的形态变化并测定各项生理指标,并用模糊隶属函数法进行植物抗逆性的综合评价。结果干旱胁迫下钟花蒲桃叶片受害最严重(VI级),5种花灌木的SOD活性均下降、丙二醛含量均上升,斑叶鹅掌藤叶绿素含量显著下降(P<0.05);淹水胁迫显著影响植物的外部形态,栀子长出新根,黄蝉形成肥大皮孔并长出大量新根和新叶,斑叶鹅掌藤大量叶片萎蔫、根部严重腐烂,狗牙花大量落叶,淹水胁迫下5种花灌木的叶绿素含量显著下降(P<0.05)、可溶性蛋白含量下降、丙二醛含量上升,斑叶鹅掌藤和狗牙花的SOD活性显著下降(P<0.05);旱涝交替胁迫下黄蝉和钟花蒲桃的叶片形态分别表现为I级和II级,5种花灌木的叶绿素含量均下降,除狗牙花SOD活性上升外,其他4种植物均下降。结论综合隶属函数和植物形态分析,5种花灌木耐旱性从强到弱依次为斑叶鹅掌藤、狗牙花、黄蝉、栀子、钟花蒲桃;耐涝性从强到弱依次为栀子、钟花蒲桃、黄蝉、斑叶鹅掌藤、狗牙花;对旱涝交替胁迫的适应性从强到弱依次为黄蝉、钟花蒲桃、斑叶鹅掌藤、狗牙花、栀子。黄蝉可配置于雨水花园和滨水河岸带等环境,斑叶鹅掌藤和狗牙花是建设屋顶花园、节水型绿地的优良植物材料,栀子和钟花蒲桃可配置于滨水绿地、淡水湿地或土壤较为湿润的环境。     

复合处理秸秆全价成型饲料饲喂肉牛的试验研究

以育成期淘汰母牛(15~18月龄)和架子牛(18~20月龄公牛)为对象,采用复合处理秸秆全价成型饲料饲喂肉牛与精、粗饲料分饲的传统饲喂模式作短期育肥比较试验.结果表明,无论育成期淘汰母牛还是架子公牛,其日增体质量皆以采食成型料组高于精、粗饲料传统饲喂组,且差异均达到显著(P<0.05)水平.初步结论:用成型饲料育肥肉牛可简化饲养程序,便于实现饲喂机械化、自动化,适宜规模化、集约化饲养,育肥效果显著.     

Productivity of deciduous woody and fodder species in relation to air temperature and precipitation in a Mediterranean environment

Productivity and its relation to air temperature and precipitation of 11 deciduous woody fodder species was studied in a semi-arid Mediterranean environment with cold winters in Macedonia, Greece. The species studied included six shrubs: Amorpha fruticosa L., Carpinus orientalis Mill, Colutea arborescens L., Corylus avellana L., Fraxinus ornus L. and Ostrya carpinifolia Scop.; and four trees: Pirus amygdaliformis Vill., Quercus pubescens Wild., Quercus sessiliflora Salish. and Robinia pseudoacacia L., with two accessions, common and spineless. Fodder species were established as one-year-old seedlings in 1987 and studied through 1994. Productivity was measured by clearcutting of the aboveground annual biomass (DM) at the end of each growing season. Samples of biomass were hand separated to determine the grazeable material (leaves and twigs). In addition, monthly values of air temperature and precipitation were correlated with annual biomass through a multiple linear regression analysis. It was found that annual biomass was statistically different among species in all the study years with Robinia being the most productive of all the species tested followed by the other two legumes Colutea and Amorpha. Proportion of grazeable material ranged widely among species and years with an overall mean of 50%. Robinia produced grazeable biomass more than 1000 kg/ha followed by Amorpha and Colutea with about 800 and 700 kg DM/ha, respectively, while all the other species produced less than 500 kg DM/ha. Yearly variation in annual biomass was found to be affected much more by air temperature, especially during the beginning of the growing season (March), than by precipitation. Coefficients of determination (r ²) were found to be high (0.50–0.80) in Amorpha, Pirus, Quercus and Robinia but only in the latter two species they were high enough (>0.70) so that the relations produced can be used for predictive purposes. This revised version was published online in June 2006 with corrections to the Cover Date.     

基于灌木林碳储量估算的植被含碳率取值

利用内蒙古东部3种灌木各器官含碳率的实测数据,探讨评估灌木林碳储量的含碳率取值问题。结果表明,1)各灌木林叶、枝和根的生物量分别占树种生物量的10%~20%、40%~60%和30%~40%,表明枝生物量占总生物量1/2左右,而根系生物量占1/3左右。2)天然山杏(Prunus sibirica)、人工山杏、人工柠条(Caragana korshinskii)和虎榛子(Ostryopsis decne)的叶、枝、根含碳率的范围分别为0.428 7~0.456 7、0.445 9~0.462 8、0.397 3~0.431 3g C·g~(-1),根的含碳率均与地上器官含碳率差异较大,叶和枝含碳率之间的差异较小。3)当天然山杏、人工山杏、虎榛子和人工柠条的地上部分和根系含碳率分别取值0.45和0.42时,其地上碳密度分别为1.370 7、1.167 7、198.873 0和2.157 3t·hm~(-2),根系碳密度分别为0.941 6、0.401 5、100.908 8和0.721 1t·hm~(-2),与实测碳密度相比,其相对误差均在6%以内。     

塔额垦区新甜饲4号高产种植技术

从选地、播种和田间管理等种植流程综述了饲用甜菜新品种“新甜饲4号”在塔额垦区高产种植技术.     

论国有良种基地建设

本文结合陕西省良种基地建设的实践经验,提出良种基地建设在良种培育工程、繁育生产及设备工程、附属工程三个方面主要的设计和建设内容、建设方式和规模及投资重点。     

鄂尔多斯高原藏锦鸡儿（Caragana tibetica）个体层次对干旱的生态适应性

藏锦鸡儿（Caragana tibetica）群落是草原与荒漠过渡带上的一个地带性植物群落类型,分布面积大,是牧草地重要的环境保护屏障。通过野外观察,对藏锦鸡儿地上部分和地下部分的形态特征以及沙堆内外的土壤水分进行了测定;采集藏锦鸡儿的根和茎的样品,在室内分析根和茎的劈裂现象。结果显示：研究区藏锦鸡儿个体平均长57 c...     

北方地区半冬性优质杂交油菜制种技术

就半冬性优质油菜的制种技术进行了陈述,提出了培育优质种子的参考建议。     

野生稻（Oryza rufipogon）新质源雄性不育恢复系的研究

发掘野生稻（O. rufipogon）新型雄性不育细胞质源,育成新质源优质米不育系的基础上进一步研究新质源雄性不育恢复系的育种技术—FA型细胞质雄性不育恢复系定向育种。用野生稻（非轮回亲本）与籼稻品种明恢63（轮回亲本）杂交和多次回交,后代再经过自交,将野生稻中的可育基因分离、转移、重组、整合到明恢63遗传背景中,获得农艺性状似明恢63,花粉和小穗全可育不分离的野生稻新质源恢复系金恢1号。用新质源不育系与金恢1号组配两个组合,其花粉和小穗育性都恢复到正常可育水平,产量高,米质优,实现了新质源不育系三系配套应用和大幅度提高杂交稻稻米外观品质的目的。这项育种新技术可以将水稻可育基因（恢复基因）转移到任一水稻品种中育成细胞质雄性不育恢复系,突破了新质源恢复系育种的技术瓶颈,极大地提高了恢复系利用稻种资源的育种潜力,为FA型新质源优质米不育系的杂交稻育种开辟了一条崭新的途径。新型（FA）细胞质源杂交稻可能对丰富杂交稻细胞质遗传多样性、提高杂交稻亲本对稻种资源的利用潜力、以及实质性提高杂交稻的稻米品质和产量水平都将产生积极和深远的影响。