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1.
树体自动滴输微肥对果树生理和果实品质的影响   总被引:3,自引:0,他引:3  
研究了树体自动滴输技术在苹果树、核桃树及柿树上的应用.结果表明:通过输施微肥可以促进树体营养生长和发育,提高核桃树花粉生活力及坐果率.节果树经输施后,果实着色显著增加,微量元素含量显著提高,铁(Fe)、锌(Zn)元素可分别比对照提高13.28%~22.90%、42.54%~43.22%,处理果实中硒(Se)及锗(Ge)的增幅较大,分别是对照的9.545倍及4.7173倍.该技术是提高我国果树生产力和改善苹果营养价值的有效方法.图1表7参18  相似文献   

2.
籼稻单倍体绿芽无性系二倍化的研究   总被引:4,自引:0,他引:4  
以籼稻单倍体绿芽无性系为材料,研究秋水仙碱等处理对水稻植株染色体二倍化的影响.结果显示:(1)以500mg/L秋水仙碱溶液振荡处理籼稻单倍体绿芽48h,其二倍化率达60%~75%,处理时间过长或处理浓度过高.虽植株染色体二倍率有所提高,但二倍体植株的得率下降;(2)秋水仙碱在愈伤组织阶段处理,其染色体二倍率远高于非愈伤组织化的绿芽二倍率,高达96%~100%,其实未经处理的绿芽愈伤组织再生植株也能获得较高的加倍率;(3)在培养基中添加多效唑(2.5mg/L)也能增加籼稻植株染色体二倍率,由原来的3.3%提高到6.6%.  相似文献   

3.
对富水型农业植物废物和其他典型城市植物固废进行了好氧堆肥实验.结果表明,富水型农业植物废物的有机质降解率最高,达到了69%.富水型农业植物废物和其他植物固废混合堆肥时能明显提高其他植物固废的降解率.富水型农业植物废物和其他典型城市植物固废混合物的质量比为2:1时,最高降解率39.1%.研究发现这与它们的组分有关,富水型农业植物含水率高达80%以上,含有的有机物质主要为易降解的蛋白质、脂肪、纤维和其他碳水化合物,C/N比在10:1~35:1之间.在堆肥物料中加入富水型农业植物废物可使堆肥的腐熟期缩短至20d,最低C/N比为18.5:1.图4表2参21  相似文献   

4.
UASB反应器高温处理酒精废液的研究   总被引:7,自引:0,他引:7  
在θ=53±1℃条件下,采用UASB用1mo培养出颗粒污泥,到运行结束时,污泥ρ(TS)为65·0g·L-1,SVI为14.0,Umax(CH4)为603.9mL·g-1·d-1,对颗粒污泥微生物类群数量和微观结构的分析表明,颗粒污泥具有活性和结构上的高效性;反映在处理效果上,使UASB具有高效稳定的运行结果:当t(HRT)24.0~18.4h,容积负荷大于20g·L-1·d-1时,甲烷含量约60%,COD去除率约91%,出水ρ(COD)1400~2000mg·L-1,厌氧生物降解的产能和治污效果良好  相似文献   

5.
序批式生物膜法同步除磷脱氮特性研究   总被引:6,自引:0,他引:6  
对淹没序批式生物膜法去除有机物和磷及同步部分脱氮的特性进行了研究。其适合的载体装填密度为30%,水力停留时间为9h,其中厌氧3h,好氧6h,进水COD负荷从0.27kg/(m^3.d)到1.32kg/(m^3.d)均可使除磷率达90%以上,脱氮率达50%-60%。淹没式生物膜法除磷脱氮工艺中的优势菌属为假单胞菌属,其次依顺序为气单胞菌属,芽孢杆菌属,微球菌属,硝化矸菌属,生物膜具有生物量大(MLVSS达5531.7mg/L),脱落污泥含磷量高(达5.67%),沉降性好(SVI为101.7)的特点,污泥产率为0.1996kg干泥/kgCOD。  相似文献   

6.
建立了香花槐组培苗快繁无性系.在改良MS培养基中添加ρ(6-BA)/mg L^-1=0.35~0.5、ρ(NAA)/mg L^-1=0.05~0.08,ρ(GA3)/mg L^-1=0.07~0.1作为生长培养基.在丛生芽诱导培养基中,ρ(6-BA)/mg L^-1=0.8~1.4,其余成分同生长培养基.两种培养方法同时使用,保证了组培苗繁殖系数为5左右.生根培养基中大量元素为MS基本培养基的1/4,ρ(IBA)/mg L^-1=0.1~0.5、ρ(IAA)/mg L^-1=1.7~2.5,香花槐组培苗的生根率为90%.炼苗后组培苗的移栽成活率为85%,且植株表型未见变异.将MS基本培养基中硝酸钾的含量由1.9g/L提高至2.199~2.931g/L,可满足每代香花槐试管苗生长25~35d期间对钾的需求.将培养基中6-BA的含量降至0.4mg/L,并采用合适的组培容器,在连续培养2、3代后,可将超度含水态苗的发生频率控制在10%以下,在6mo内生产100万株香花槐组培移栽苗.图1表1参16  相似文献   

7.
三价钇对紫露草的遗传毒性研究   总被引:5,自引:0,他引:5  
用紫露草四分体微核试验法和紫露草雄蕊毛细胞突变法研究了稀土元素三价钇的遗传毒性.结果表明:Y3+能引起紫露草四分体微核率显著升高,提示Y3+是诱变剂或纺锤丝毒剂;Y3+能引起雄蕊毛细胞突变率显著升高,进一步明确Y3+是诱变剂.  相似文献   

8.
采用气相色谱法研究了35%苄·丁可湿性粉剂中丁草胺在2006年和2007年湖北省、广东省2年两地水稻田土壤和水中的残留降解动态和最终残留量。研究结果表明丁草胺在土壤和田水添加回收率分别为82.78%~93.20%和90.31%~93.51%,丁草胺在稻田土壤和田水中降解动态符合一级动力学指数模型,在湖北省和广东省水稻田土壤中的半衰期分别为3.21~3.83d、2.49~3.66d,水稻田水中的半衰期分别为1.20~1.66d、1.13~1.48d。861g(a.i.)·hm^-2和高剂量1292g(a.i.)·hm^-2两个剂量施药后丁草胺在稻田土壤中的最终残留量为0.0010-0.0029mg·kg^-1。  相似文献   

9.
稻草快速腐熟及盆栽试验初报   总被引:1,自引:0,他引:1  
采用实验室培养发酵、谱学分析、盆载试验的方法,研究了化学前处理、化学-生物联用处理对稻草腐熟效果的影响。结果表明,稻草经化学熟化剂A、B预处理24h后,其IR结晶指数从1.105分别下降到1.046、1.079;经化学-生物联用技术处理,大大加速稻草腐热,其中化学熟化剂A-生物熟化剂A联用处理,可使稻草在14d内腐熟。水稻增产10%以上。  相似文献   

10.
亚硝酸盐氮对草鱼种耗氧率的影响及适应性研究   总被引:1,自引:0,他引:1  
通过测定全血红蛋白和高铁血红蛋白及耗氧率,研究了草鱼种在NO-N作用下的生理变化和对NO-N的适应性,结果表明:ρ(NO-N)在O~4mg·L-1范围内可使草鱼种耗氧率增加,并于1mp·L-1和4mg·L-1处出现峰值和次峰值;经暴露处理的鱼种在恢复21d后,显示出对NO-N的适应性.  相似文献   

11.
Bumblebees can avoid recently depleted flowers by responding to repellent scent-marks deposited on flower corollas by previous visitors. It has previously been suggested that avoidance of visited flowers for a fixed period would be a poor strategy, since different plant species vary greatly in the rate at which they replenish floral rewards. In this study, we examined the duration of flower repellency after an initial bumblebee visit, using wild bumblebees (Bombus lapidarius, B. pascuorum and B. terrestris) foraging on four different plant species (Lotus corniculatus, Melilotus officinalis, Phacelia tanacetifolia and Symphytum officinale). We constructed a model to predict flower visitation following an initial visit, based on the nectar secretion pattern of the different plant species, the insect visitation rate per flower, and the search and handling times of bumblebees foraging on the plant species in question. The model predicts an optimal duration of flower avoidance which maximises the rate of reward acquisition for all bees. However, this optimum may be open to cheating. For two plant species, the evolutionary stable strategy (ESS) is a shorter duration of flower avoidance than the optimum. We found the duration of flower avoidance was markedly different among flower species and was inversely related to nectar secretion rates. The predicted ESSs for each plant species were close to those observed, suggesting that the key parameters influencing bumblebee behaviour are those included in the model. We discuss how bees may alter the duration of their response to repellent scents, and other factors that affect flower re-visitation.  相似文献   

12.
马齿苋有性繁殖特性研究   总被引:1,自引:0,他引:1  
马齿苋有性繁殖特性研究结果表明,马齿苋的第1朵花在播种后44d开始开放,以后不断地形成花蕾和开花,并且边开花边结籽、种子成熟后即自行开裂、散落,这种特性给种子收集和生产大量用种带来许多困难,成为制约马齿苋规模化栽培的重要因子.因此,如何找到一套简单易行、操作方便、省时省力、能用于大量生产马齿苋种子的方法,是需要继续在生产实践中探索的问题.  相似文献   

13.
Bee-pollinated plants are frequently dichogamous: e.g. each flower has a discernable male and female phase, with only the male phase offering a pollen reward. Pollen-collecting bees should therefore discriminate against female-phase flowers to maximise their rate of pollen harvest, but this behaviour would reduce plant fitness due to inferior pollination. Here, we test the hypothesis that flowers use pollen-mimicking floral guides to prevent flower-phase discrimination. Such floral guides resemble pollen in spectral reflection properties and are widespread among angiosperm flowers. In an array of artificial flowers, bumblebees learned less well to discriminate between flower variants simulating different flowering phases when both flower variants carried an additional pollen-yellow guide mark. This effect depended crucially on the pollen-yellow colour of the guide mark and on its spatial position within the artificial flower. We suggest that floral guides evolved to inhibit flower-phase learning in bees by exploiting the innate colour preferences of their pollinators.  相似文献   

14.
This paper is the first of three on the coffee production system consisting of (1) the coffee plant, (2) coffee berry borer (CBB) and (3) the role of CBB parasitoids. A previous simulation model of the coffee plant was developed using data from Brazil where coffee phenology is characterized by distinct seasonal flowering (Gutierrez et al., 1998). In contrast, flowering in Colombia is continuous with low seasonality. To capture the differences in coffee phenology and growth in the two climatic regions, the Gutierrez et al. (1998) model was modified using new data from Colombia.The modifications to the model include:
(1)
The effect of solar radiation on floral buds initiation;
(2)
An age structure population model to track the daily input and development of the floral buds;
(3)
The effect of leaf water potential on breaking dormancy in flower buds, and hence on the timing and intensity of flowering;
(4)
The incorporation of both the vegetative and the reproductive demands to predict the photosynthetic rate.
(5)
The effect of low temperature on photosynthesis and defoliation.
Other aspects of the model were re-interpreted and refinements made to generalize its structure for use across coffee varieties and geographic areas. The model, without modification, realistically simulates field data from Brazil and two Colombian locations having different varieties, patterns of rainfall and hence flowering phenology.The model will be used as the base trophic level for incorporating CBB and high tropic levels effects, and for the analysis of management options in the coffee production system.  相似文献   

15.
A field study was conducted to measure the dislodgeable residues of profenofos applied to jasmine (Jasminum sambac) and risk assessment was done for laborers engaged in picking of flower buds. Profenofos was applied at 0.10, 0.15, and 0.20% concentration and the jasmine bud samples were analysed for residues using GC. The initial deposit of 1.6–3.8, 3.8–7.1, and 5.2–7.6 µg cm?2 was detected on jasmine buds at 0.10, 0.15, and 0.20% concentration, respectively. At the recommended dose of 0.10%, the half-life was 1–2 days and the dislodgeable residues disappeared within 7 days. The results indicate faster disappearance of dislodgeable residues on jasmine buds. Risk assessment was done based on dislodgeable foliar residues and exposure estimates based on surrogate data and expressed as Margin of Exposure (MOE). The entry restrictions for exposure of jasmine flower pickers to profenofos, would be at least, 1 day following application, for the recommended concentration of 0.10% (MOE = 106) and 3 days, at higher concentrations of 0.15% (MOE = 156) and 0.20% (MOE = 115).  相似文献   

16.
Effects of salicylic acid (SA) on seed germination, seedling growth, flowering and biochemical activities were studied out in four cowpea (Vigna unguiculata) genotypes in control environments. The results revealed that both germination and seedling growth were negatively affected by 0.02%. SA application, however did not affect the size of full expanded buds, time of 50% flowering and date of flower initiation. A maximum increase in peroxidase (EC1.11.1.7) activity was observed in UPC 4200 over other genotypes. No significant change in the content of total soluble and intercellular fluid proteins was observed except in UPC 4200 genotype. SA induced accumulation of total soluble sugars more at flowering stage than at seed setting stage. It is evident from the present study that UPC 4200 genotype was more responsive to salicylic acid both in terms of increased peroxidase activity and less negative effect on morphological attributes, thus suggesting its wider use without negative impact on environment as salicylic acid has been reported in plants.  相似文献   

17.
Experimental Demonstration of an Allee Effect in American Ginseng   总被引:6,自引:0,他引:6  
Abstract: Harvesting of wild American ginseng (   Panax quinquefolius ) for the herbal trade has lowered natural population sizes. We tested for reproductive limitation due to small population size (a form of the Allee effect) by experimentally planting "natural" populations numbering 4, 16, and 64 using 4-year-old cultivated plants. Plant size traits and reproductive traits ( bud, flower, green fruit, and mature fruit) were recorded through the ensuing summer. Fruit production per flower and per plant increased in proportion to flowering population size (  p = 0.0063 and p = 0.0017, respectively), strongly suggesting that an Allee effect occurs in very small populations. The increase in fruit production was not explained by either plant or inflorescence size differences. Although population size-dependent pollination, through insufficient pollinator visitation rate or pollen transfer rate, seems the most likely cause of the observed effects, our limited observations of pollinators were not sufficient to demonstrate a change in pollination rates as a function of population size. Knowledge of the presence as well as the mechanism underlying this Allee effect may be especially useful for management and determination of minimum viable population size of the species in the wild.  相似文献   

18.
Photosynthesis and sink activity of wasp-induced galls in Acacia pycnantha   总被引:1,自引:0,他引:1  
Dorchin N  Cramer MD  Hoffmann JH 《Ecology》2006,87(7):1781-1791
Although insect galls are widely known to influence source-sink relationships in plants, the relationship between photosynthesis and gall activity has not been extensively studied. In this study we used 14CO2, photosynthesis, and respiration measurements to examine the capacity of bud galls induced by the wasp Trichilogaster signiventris (Pteromalidae) as carbon sinks in Acacia pycnantha. Galls of this species develop either in vegetative or reproductive buds, depending on the availability of tissues at different times of the year, and effectively eliminate seed production by the plant. Photosynthetic rates in phyllodes subtending clusters of galls were greater than rates in control phyllodes, a result we attributed to photosynthesis compensating for increased carbon demand by the galls. Contrary to previous studies, we found that photosynthesis within galls contributed substantially to the carbon budgets of the galls, particularly in large, mature galls, which exhibited lower specific respiration rates allowing for a net carbon gain in the light. To determine the sink capacity and competitive potential of galls, we measured the proportion of specific radioactivity in galls originating from either vegetative or reproductive buds and found no difference between them. The proportion of the total amount of phyllode-derived 14C accumulated in both clustered and solitary galls was less than that in fruits. Galls and fruits were predominantly reliant on subtending rather than on distant phyllodes for photosynthate. Solitary galls that developed in vegetative buds constituted considerably stronger sinks than galls in clusters on inflorescences where there was competition between galls or fruits for resources from the subtending phyllode. Wasps developing in solitary vegetative galls were correspondingly significantly larger than those from clustered galls. We conclude that, in the absence of inflorescence buds during summer and fall, the ability of the wasps to cause gall formation in vegetative tissues tempers intraspecific competition and substantially increases the availability of plant resources for the development of wasps in such galls.  相似文献   

19.
Caper is an important plant because of its high adaptability to marginal agriculture fields that are not suitable for agricultural crops. Different parts of caper such as roots, fruits, flowers and buds can be used to increase the inhabitant's income. The goal of this research is to determine germination rate and percentage of caper according to different duration of cold stratification (10, 20, 30, 40, 50 and 60 days) treatments. Cold stratification procedures under greenhouse condition were applied for eliminating seed dormancy to find the most suitable germination conditions because the presence of seed dormancy causes difficulties in seedling production. The seed germination started and stopped 21 and 57 days after sowing, respectively. While the highest germination percentage (46.6%) was obtained in seeds that were cold stratified for 60 days, the lowest germination percentage (3.6 7%) was determined in control seeds.  相似文献   

20.
丝瓜对食品废水的净化功能及经济效益   总被引:14,自引:0,他引:14  
本文研究了丝瓜(Luffacylindrica)在水面上的水培技术,对食品工业废水(啤酒废水)的净化功能及其经济效益。其试验结果表明:采用水培技术将丝瓜栽种在水面上是完全成功的。该法已经被应用到无锡市酿酒总厂食品工业废水净化处理。在5月份,丝瓜对啤酒废水中污染物TN的净化率为78.6%,TP78.0%,NH+_4-N99.6%,COD22.5%,浊度80.9%。在6月份,丝瓜的净化率为TN89.1%,TP90.4%,NH+_4-N99.2%,COD44.1%和浊度86.4%。由此可见,丝瓜是一种对食品废水净化的优良植物,其经济效益也很显著,每亩水面丝瓜(果实)可达2000kg~2500kg,经济价值达2000元~2500元。  相似文献   

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