棉花幼苗侧根发生的化学诱导研究 Ⅲ.Ca~(2+)对棉花幼苗侧根发生和根系IAA含量的影响研究初报

清水或 DPC 200ppm 溶液浸种培养的棉花幼苗在移栽时用含 Ca~(2+)30ppm 的 CaCl_2溶液漫根2小时处理,栽后8天观察发现,两种浸种方式,Ca~(2+)均能促进棉苗侧根的发生,并提高根系 IAA 含量。但 Ca~(2+)处理 DPC 降低根对棉酚含量的效应无明显影响。上述试验结果显示出 Ca~(2+)与诱导棉苗侧根发生和调节根系 IAA 水平之间存在着某些内在的联系,这可能涉及到 Ca~(2+)·CaM系统(胞内第二信使系统)与植物激素效应之间的关系。     

栽培防病措施对防治小麦白粉病的重要作用

为了解栽培措施对防治小麦白粉病的作用,通过不同栽培措施对病情产生不同影响的大量田间调查,明确了小麦早播、密播,过量水、肥条件下的旺苗和种植高度感病品种,都会加重小麦秋苗带菌量。短期播种、合理密植、视墒灌水、配方施肥、培育小麦壮苗及避免种植高感品种等均能减轻小麦秋苗带菌量。小麦秋苗带菌量大,则翌春病菌越冬菌源量也大。种植高感品种在田间有发病中心的作用。应把栽培防病措施规范化、科学化、制度化,以充分发     

An analysis of structure of tree seedling populations on a Lahar

The structure of a tree seedling population is dependent on the interaction of several processes including seed dispersal, germination, survival, and competition on a physical landscape. Structural components (composition, size distributions, spatial distributions, age distributions, density, and history) of a tree seedling population on the Muddy River Lahar on the east side of Mount St. Helens were examined over a range of extents (1/10 m to 1000 m). Many of these component have rarely been examined at the larger extents listed here. Composition reflected distances to seed source and seed morphology. Seedling sizes are inversely proportional to depth to a buried soil if one existed. Spatial patterns indicated that seedling are clustered for tree seedlings less than 200 m apart, random for tree seedling from 200 m to 400 m and uniform for seedling greater than 400 m apart. This was confirmed by two measures of multidimensional spatial point pattern. Age distributions did not reflect the size distributions; old seedlings could be almost any size, young seedlings were constrained to be small in size. Densities appear to be typical for forests in the area. History of disturbance events (the lahar establishment, and successive ash, pumice, and erosion) has strongly influenced this tree seedling community.     

陕北地区垂柳大苗的快速培育

通过柳杆扦插以及嫁接方法而快速繁育垂柳大苗的具体方法和技术措施,对缓减陕西省榆林地区当前市场垂柳大苗的供需矛盾具有比较重要的意义。     

Tissue Culture Response from Seedling Explants of Commercial Barley Cultivars Grown in Bulgaria

Abstract

Only a few studies have been conducted in which regenerability of barley has been examined. In the current study, 17 barley genotypes (nine two-row malting type: Aster, Emon, Ruen, Jubiley, PV101, Körten, Krassi 2, Perun and Igri, and eight six-row feed types: Karnobat, Hemus, Jerun, Veslets, Aheloi 2, Diana, Panagon, and Izrgev) were evaluated for tissue-culture response from seedlings during a three-year period. Regenerable calli were obtained from all tested genotypes. Although there was much variation in regeneration capacity among the cultivars, plants were obtained from all cultivars. The majority of green plants grown to maturity were fertile and normal in appearance. The frequency of embryogénie callus induction and regenerability was influenced by genotype and growth conditions of the donor plants. Genotype was the most important determinant of the in vitro response. The best in vitro performance, based on ability to form regenerable calli and to regenerate plants was observed for Ruen, Aster, and Emon.     

落叶松播种苗使用钼酸铵根外追肥试验报告

通过对落叶松播种苗根外追施钼酸铵液，促进苗高，地径生长，较明显地提高了苗木整体质量，对苗木木质化和提高苗木对不良环境的抵抗力有着积极的促进作用。     

Enhancement in Nutrient Accumulation and Growth of Oil Palm Seedlings Caused by PGPR Under Field Nursery Conditions

Abstract

Plant growth promoting rhizobacteria (PGPR) (e.g., Azospirillum and Bacillus spp.) have been reported to enhance growth and fix N₂ with several nonleguminous crops. These rhizobacteria have the potential to be applied to oil palm seedlings and, consequently, reduce the cost of nitrogenous fertilizer. The rhizobacteria are also known as a bioenhancer for the ability to increase root growth and enhanced water and nutrient absorption by the host plants. An experiment was carried out in the field nursery station, Federal Land Development Authorities (FELDA), Bukit Mendi, Pahang, Malaysia, to observe the effects of PGPR inoculation on enhanced nutrient accumulation and plant growth (tops and roots) of oil palm seedlings under field nursery conditions. The inoculation process showed positive response in enhancing higher accumulation of nitrogen (N), phosphorus (P), and potassium (K) in the plant tissues, enhanced root dry weight and top growth (dry matter and leaf chlorophyll content) of the host plants under field nursery conditions.     

2006年贵州省赫章县秋季小麦条锈病调查

为了解中国新发现的小麦条锈病菌越夏区贵州省赫章县小麦条锈病秋季发生情况,2006年秋季笔者主要对该县古基乡、野马川镇、六曲河镇进行了调查,共调查119块地,自生麦病田率为55%,秋播小麦病田率为20.20%。古基乡发病较多,自生麦苗上有多个发病中心,有的秋播小麦田块亦呈现病叶较集中现象。在海拔1660-1910m范围内,都有小麦条锈病发生,说明当地越夏菌源能够为本地区秋苗发病提供充足菌量。对进一步研究内容进行了讨论并提出了赫章县小麦条锈病治理措施。     

不同轻型基质对湿地松容器苗生长影响的研究

采用5种基质培育1年生湿地松容器苗，对不同基质培育的苗木地径、高度、鲜干重等指标进行了测定。结果表明，不同轻型基质配方对湿地松容器苗质量影响明显，表现较好的配方是Ⅳ号、Ⅱ号、Ⅲ号基质；同时，容器大小选择B型较好：     

宜昌楠苗木繁育技术初步研究

通过对宜昌楠(Machilus ichangensisRehd.Et)进行种子育苗、幼苗移栽和定植苗的修剪等试验,结果表明:宜昌楠种子宜在元旦前后播种并覆盖发酵草,出苗率可达到98%;每年3月幼苗根部打泥浆后移栽,幼苗成活率达到95%;对定植苗进行修剪,特别是春剪有利于侧芽的增长和主茎基部的增粗。