适应湖北地区的优良草坪草——草地早熟禾

草地早熟禾原产欧洲、亚洲东部和非洲北部,我国东北、华北、西北等地也有野生。我所于1980年从中国农科院畜牧所引进一批国外栽培的草地早熟禾优良品种进行试种观察。1982年,荷兰尼瓦兹(NIVAZ)种子中心牧草种子专家来我省考察,向我所赠送的35个早熟禾品种,也进行了试种观察。近年来除在武昌试行栽培外,还在钟祥、襄樊等地进行适应性试种观察。结果表明,此草应性广,草质好,耐萌性强,易于栽培,是一种颇有发展前途的优良草坪草。在春末,深秋各刈割一次。

草坪建植新法

一、坪床工程 1.清理对欲建草坪的场地,挖除树木、树桩和树根,清除坪床面以下 60厘米层内的石头、瓦砾,其土壤过筛.清除杂草,可用物理防除,即手工或土壤翻耕机具清除杂草 ; 或用化学防除,即用除草剂茅草枯、磷酸甘氨酸、草甘膦等喷雾 10厘米高的杂草,7～ 30天以后可翻耕.土壤病虫害防治,用熏杀剂,如将溴甲烷或氯化苦毒气注入聚乙烯薄膜覆盖的坪床进行土壤消毒,24～ 48小时后可播种,或用棉隆和威百亩以灌水的方式与土壤混合,3周后方可播种 .

Effects of Different Light Qualities on Activity and Gene Expression of Caspase-like Proteases in Tobacco Leaves

[Objective] The study aimed to investigate the activity and gene expression of caspase-like proteases in tobacco leaves growing under different light qualities. [Method] By covering tobacco plants with white, red, yellow, blue and purple films to obtain different light quality, the changes of chlorophyll content, activity and gene expression of caspase-like proteases in the tobacco leaves were studied. [Results] Compared with treatments of white, red and yellow film, blue and purple films delayed the decrease of chlorophyll content and senescence of tobacco leaves at the late growth stage, and relatively lowered the activity and gene expression of caspase-like proteases during growth, development and senescence periods. [Conclusion] Different light qualities exhibited various effects on the growth, development and senescence of tobacco leaves, possibly by affecting the activity and gene expression of caspase-like proteases to some extent.

草坪草种资源引种开发研究初报——以哈尔滨市绿化为例

一、引种的目的和经过 草坪是城市绿化的重要组成部分,随着我市国民经济的不断发展,城市不断扩大,以及人民物质生活和文化生活的不断提高,对草坪建设的需要就越来越迫切。

Effects of Exogenous Abscisic Acid and Water Stress on the Growth Response of Subterranean Clover of Different Genotypes

The response of subterranean clover ( Trifolium subterraneum L.) to different abscisic acid (ABA) concentrations (10 -6 , 10 -5 , 10 -4 mol/L) in nutrient solution and to water stress were studied in growth room. Six cultivars of contrasting yield capacity were compared. Plants remained growing in Hoagland solution or pots until at least four full_developed leaves appeared. The ABA was then applied and the fresh weight, leaf number and length of the largest root were measured at 1, 4, 7 and 11 d after ABA treatment. The above parameters were also measured at 15 d under water stress. In all the tested genotypes ABA caused similar reduction in these growth parameters, as well as a significant decrease of leaf water potential which was dependent on ABA concentration. The average growth reduction after 11 d under 10 -4 mol/L ABA coincided with the range of these crops under water stress in pot experiments. On average of the different genotypes, leaf number, area of full_developed leaf and the dry weight per plant decreased by about 50% whereas the root/shoot ratio increased by 80%.The genotype variation and ranking for this treatment were rather similar to the same genotypes in pot experiments. The genotypes, Clare, Nuba and Seaton Park, showed the best results under both control and ABA treated conditions and water stress conditions. The similarity between the response to ABA in nutrient solution and to water stress opens the possibility to use this approach as a way to quantify the drought resistance of subterranean clover genotypes.

Uptake of Organic Phosphorus by Arbuscular Mycorrhizal Red Clover

The capacities of two arbuscular mycorrhizal (AM) fungi, Glomusmosseae and Glomus versiforme, to mineralize added organic P werestudied in a sterilized clacareous soil. Mycorrhizal (inoculated witheither of the AM fungi) and non-mycorrhizal red clover (Trifoliumpratense L.) plants were grown for eight weeks in pots with upperroot, central hyphal and lower soil compartments. The hyphal and soilcompartments received either organic P (as Na-phytte) or inorganic P(as KH_2PO_4) at the rate of 50 mg P kg^-1. No P was added to theroot compartments.

Effects of Nitrogen Deposition on Tundra Vegetation Undergoing Invasion by Deyeuxia angustifolia in Changbai Mountains

In recent years, herbaceous species such as Deyeuxia angustifolia （Kom.） Y. L. Chang has invaded alpine tundra regions of the western slope of the Changbai Mountains. Because atmospheric nitrogen deposition is predicted to increase under a warming climate and D. angustifolia is sensitive to nitrogen addition, field experiments were conducted from 2010 to 2013 to determine the effect of increased nitrogen deposition on the mechanisms of D. angustifolia invasion. The goal of this study is to evaluate the impact of increased nitrogen deposition on the changes in alpine tundra vegetation （consisting mostly of Rhododendron chrysanthum Pall. and Vaccinium uliginosum Linn.）. The results showed that： 1） simulated nitrogen deposition affected overall characteristics and structure of R. chrysanthum and E uliginosum communities and had a positive impact on the growth of tundra vegetation invaded by 1）. angustifolia; 2） R. chrysanthum was more resistant to invasion by D. angustifolia than V.. uliginosum; 3） simulated nitrogen deposition could improve the growth and enhance the competitiveness of D. angustifolia, which was gradually replacing R. chrysanthum and V. uliginosum and might become the dominant species in the system in future, transforming alpine tundra into alpine meadow in the Chanebai Mountains.

Foliar modifications induced by inhibition of polar transport of auxin

The effects of auxin polar transport inhibitors, 9-hydroxy-fluorene-9-carboxylic acid (HFCA); 2, 3, 5-triiodobenzoic acid (TIBA) and trans-cinnamic acid (CA)on leaf pattern formation were investigated with shoots formed from cultured leaf explants of tobacco and cultured pedicel explants of Orychophragmus violaceus, and the seedlings of tobacco and Brassica chinensis. Although the effective concentration varies with the inhibitors used, all of the inhibitors induced the formation of trumpet-shaped and/or fused leaves. The frequency of trumpet-shaped leaf formation was related to the concentration of inhibitors in the medium.Histological observation of tobacco seedlings showed that there was only one main vascular bundle and several minor vascular bundles in normal leaves of the control, but there were several vascular bundles of more or less the same size in the trumpet-shaped leaves of treated ones.These results indicated that auxin polar transport played an important role on bilateral symmetry of leaf growth.

White Mulberry （Morus alba） Foliage as a Feeding Supplement for Growing Calves

The aim of this study was to evaluate the feed consumption and weight gain in calves fed with a nutritional block made of white mulberry （Morus alba） for a 90-day-period, involving dry season months （March-May） in Tuxpan, Veracruz, Mexico. A total of 45 growing Zebu x Swiss calves with an average weight of 200 kg were assigned randomly in three groups of 15 animals, and the following treatments of nutritional block were offered to each group： grazing animals （To）, grazing animals plus nutritious block with white mulberry （T1）, and grazing animals plus nutritious block without white mulberry （T2）. A consumption of 0.545 kg/d from block in treatment T1 was observed, significantly improving calves growing and showing a weight gain of 0.933 kg/d. Use of white mulberry in nutritional blocks is a good alternative for growing calves, as a feeding strategy given the seasonality of pasture production in the tropics.

Predicting Compensatory Growth and Reproduction in Agricultural Weeds Using a Plant＇s Growth Rate Trajectory： A Test with Defoliation of Abutilon theophrasti

A plant＇s capacity to compensate for pest damage as a function of resource availability needs to be predictable in order to apply biocontrol agents effectively. In this research, it was hypothesized that a weedy plant species＇ capacity to compensate for defoliation is related to how resource availability affects a plant＇s growth trajectory. Growth rate trajectory is defined as the percent change in relative growth rate or the slope of a plant＇s relative growth rate. 90 Abutilon theophrasti, a common weed species, in cultivated fields of corn and soybean, grew in a greenhouse for 70 d under three nitrogen （N） fertilization treatments. ＂Unfertilized＂ plants were not fertilized, ＂bulk＂ fertilized plants received 0.6 g N on day 15 and ＂exponential＂ fertilized plants received a total of 0.6 g N supplied at an exponential rate of 10% per day with a starting concentration of 0.02 g N on day 15. On day 25, 15 plants in each N treatment had 75% of total leaf area removed. Biomass and reproductive compensation were determined after 50 d and 70 d of growth. Results showed that bulk plants had the greatest absolute growth, but also the greatest decline in growth rates and the least capacity for compensation. Unfertilized plants had the lowest absolute growth, but declines in growth rates were similar to bulk plants with only a slightly greater compensatory capacity. Exponential plants had intermediate absolute growth, but the least decline in growth rates and the greatest capacity for compensation. This experiment indicates that a plant＇s growth rate trajectory, and not high or low relative growth rates or N availability per se, can be used to predict a weedy plant＇s capacity to compensate for herbivory, and has implications for biocontrol of weedy species.

辽南地区草坪建植技术

草坪是现代城市绿化的重要组成部分,其覆盖面积是评价现代化城市建设水平的重要标志之一。绿色的草坪不仅可减轻太阳辐射、净化空气、吸滞尘土,还能防止噪音、保持水土、调节小气候环境,且具有较强的观赏性,是人类生活不可缺少的场地。

Growth,phenology and N-utilization by invasive populations of Gunnera tinctoria

Aims Gunnera tinctoria is an unusual N-fixing plant species that has become invasive worldwide,generally in environments with a low evaporative demand and/or high rainfall.Amongst the many mechanisms that may explain its success as an introduced species,a contrasting phenology could be important but this may depend on an ability to grow and utilize nutrients under sub-optimal conditions.We examined whether G.tinctoria has an advantage in terms of a contrasting phenology and N-fixing capability,in comparisons with Juncus effusus,the native species most impacted by G.tinctoria invasions.Methods We made phenological assessments on a weekly or bi-weekly basis on long-established populations on Achill Island,Ireland,during 2016-2017.Data on leaf and inflorescence number,total leaf area,light interception and above-ground biomass were collected alongside measurements of soil temperature,moisture and oxidation-reduction potential.The significance of N-fixing ability for supporting seasonal growth was assessed usingδ15N isotopic assessments,together with in situ acetylene reduction measurements.Important Findings The timing of the initiation of growth of G.tinctoria and J.effusus varied between 2016 and 2017,with the earlier emergence and expansion of leaves of G.tinctoria,and the largest above-ground biomass associated with higher water availability.The early growth of G.tinctoria was dependent on preformed structures,with maximum canopy development occurring in late May,prior to that of J.effusus.Whilst N-fixation was observed in March,this made a more significant contribution to growth during the later stages of canopy development.Based onδ15N isotopic analyses,early growth was predominantly associated with N-remobilization from the rhizomes,whilst seedlings were largely reliant on N-fixation.This emphasizes the importance of nutrient mobilization for early growth and shows that the importance of an N-fixing capability may vary developmentally,as well as during different stages of the invasion process.