影响蓖麻种子萌发因子的研究

对蓖麻种子萌发进行温度、水分、播种深度、种皮等处理试验，结果表明，温度和播种深度显著影响蓖麻种子萌发，其中土壤温度低和覆土厚是导致蓖麻种子萌发缓慢的主要因子;种皮的存在有利于菌麻种子萌发;土壤水分含量在10％以上能满足蓖麻种子萌发。     

5个苹果品种花粉发芽力观察

在室内对5个苹果品种花粉发芽力进行镜检观察。结果表明,不同苹果品种花粉发芽力不同,红星>金冠>富士>祝光>国光。多数品种边花比中心花的花粉发芽力高。相同花粉用GA 150ppm 和2,4-D 10ppm 处理,能显著提高花粉发芽力。多品种混合花粉比单品种花粉发芽力强。花粉密度大,有利于发芽力的提高。     

浸种时间对莴笋种子萌发的影响

对浸种不同时间的莴笋种子的发芽率、吸水量、电导率进行测定 ,试验结果表明 :未经浸种而直接催芽的莴笋种子 ,与浸种 8、10h的种子发芽率差异不显著 ;无论是浸种还是直接置床 ,莴笋种子经10h均能达到充分吸胀状态     

H_2O_2浸种对提高陈年种子发芽率的研究

适当浓度的H_2O_2液浸种陈年番茄、萝卜种子,能显著提高发芽率。其中,番茄以0.25％H_2O_2浸种4天,萝卜以0.5％H_2O_2浸种3天的效果最佳。应用垂直平板聚丙烯酰胺凝胶电泳法,分析番茄种子和萝卜种子萌发过程中的过氧化物酶同工酶,结果表明,处理组的酶带数目与酶活性强弱跟发芽率的提高相一致。说明采用一定浓度的H_2O_2浸种陈年种子,可使某些同工酶提前出现,种子的生理生化代谢增强,并能破坏抑制物质的抑制作用,从而提高种子萌发率。     

镧对大豆种子活力的影响研究

实验用不同浓度镧液处理大豆种子,研究镧对大豆种子萌发的影响。结果表明:低浓度的镧对大豆种子的萌发有明显的促进作用,其中以5m l/L为优;高浓度的镧对大豆种子的萌发有抑制作用,甚至有毒害作用。     

论凯丰宣传思想的形成过程

凯丰同志是一位优秀的宣传家,他的宣传思想在革命战争年代尤其是抗日战争时期和解放战争时期对发动和组织全国各界人士参与抗战起到了一定的促进作用。凯丰同志的宣传思想也是随着革命的深入不断地发展、成熟起来的。以时间顺序对凯丰同志宣传思想形成过程进行梳理,具体阐述了其宣传思想在萌芽、发展和成熟等各个时期的主要内容。     

中国新闻体裁演进问题新探

新闻作为一种文体,其出现、变革、演进,有其历史渊源和发展规律可循。新闻写作理论,多从横的方面来讲各种体裁的写作原理和方法,本文专门从纵的方面探讨新闻体裁的来龙去脉及其演进。     

The role of the brown-eared bulbulHypsypetes amaurotis as a seed dispersal agent

The role of the brown-eared bulbul,Hypsypetes amaurotis, as a dispersal agent for seeds of fruiting plants was studied by field observations for two years, in parallel with laboratory experiments on seed germination. Bulbuls consumed fruits of 53 species from 24 plant families. The fruits of these plants had similar color and size, and these characteristics were likely to enhance the feeding efficiency of the frugivore. Laboratory experiments on 20 food plant species demonstrated that: (1) no seeds were injured by passing through the bulbul's gut; (2) seeds that had passed through the bulbul's gut were still able to germinate and (3) fruit pulp reduced germination ability. When pulp was removed by passing through bulbul's gut, or by hand, germination was improved. An estimate of the home range of six bulbuls suggested that they may transport seeds for at least 300 m.     

Fitting and comparing seed germination models with a focus on the inverse normal distribution

This paper reviews current methods for fitting a range of models to censored seed germination data and recommends adoption of a probability‐based model for the time to germination. It shows that, provided the probability of a seed eventually germinating is not on the boundary, maximum likelihood estimates, their standard errors and the resultant deviances are identical whether only those seeds which have germinated are used or all seeds (including seeds ungerminated at the end of the experiment). The paper recommends analysis of deviance when exploring whether replicate data are consistent with a hypothesis that the underlying distributions are identical, and when assessing whether data from different treatments have underlying distributions with common parameters. The inverse normal distribution, otherwise known as the inverse Gaussian distribution, is discussed, as a natural distribution for the time to germination (including a parameter to measure the lag time to germination). The paper explores some of the properties of this distribution, evaluates the standard errors of the maximum likelihood estimates of the parameters and suggests an accurate approximation to the cumulative distribution function and the median time to germination. Additional material is on the web, at http://www.agric.usyd.edu.au/staff/oneill/ .     

蓖麻种子萌发过程中主要物质变化

利用哲蓖三号蓖麻品种，在田间栽培条件下，对蓖麻种子萌发过程中干物质重量、吸水量、脂肪含量和蛋白质含量进行测定分析，结果表明，干物质和脂肪含量呈递减趋势，吸水量和蛋白质含量呈递增趋势。