Acclimation abilities of three tropical rainforest seedlings to an increase in light intensity

Current practices in many nurseries involve the germination of tropical rainforest seedlings in shaded conditions and transferral, at a later date, to environments with greater light intensities. Determination of the ability of these seedlings to acclimate to increased light intensities will allow seedling stock to be processed with maximum efficiency within the nursery. The acclimation abilities of three species, Agyrodendron actinophyllum, Cardwellia sublimis, and Flindersia brayleyana, commonly found in north Queensland's rainforests were investigated in this study. These particular species are highly valued for their cabinet timber qualities and are being reared in nurseries for use in reforestation trials and programs in north Queensland. Seedlings were initially raised in greenhouse conditions under two layers of shade cloth (16% of full sunlight) and then transferred into full sunlight at three different ages (3 weeks, 10 weeks, 14 weeks). Upon transfer, organ ratios and the direction of dry matter distribution was determined for each species and age group. Approximately 3 months after the seedlings were transferred, the acclimation ability of each species and age group was then determined. Dry matter distribution was found to change with age, irrespective of light environment. Individuals within a species with larger root systems and thicker or more dense leaves had a greater acclimation ability than those with smaller root systems and thinner or less dense leaves. Furthermore, individuals within a species whose dry matter distribution upon transfer was directed towards developing a large root system, and a small photosynthetic area and mass, had a greater acclimation ability than those whose dry matter distribution was directed away from such morphologies. Awareness of these relationships allows a better understanding of seedling response to gap formation in natural forests, and also allows plant nursery operators to make a more informed decision about when to move seedlings to environments with a higher light intensity.     

杏花器官组织抗寒性研究

通过人工模拟霜害试验,研究了杏花抗寒性与花器官组织结构的关系,并统计了冻害率。结果表明:4个仁用杏品种的抗寒性由强到弱为优一、白玉扁、一窝蜂、龙王帽;在同一朵花中,抗寒性强弱为花瓣>雄蕊>雌蕊;未接种冰核细菌的花比接菌的抗寒性强。-3℃低温处理后,各品种的子房显微结构均受到不同程度的破坏。     

罹患口腔炎乌苏里蝮的相关生理学指标分析

口腔炎是人工养殖蛇类的常见病之一,为了深入了解和尽早做好预防工作,对罹患口腔炎的成年雄蛇乌苏里蝮(Gloydius ussuriensis)进行解剖观察,并检测了相关器官的系数、血液学指标和激素等。结果表明:整体肥满度、躯体肥满度、肾系数等数值罹患口腔炎蛇略高于健康蛇;而肝系数、精巢系数和脂肪体系数等罹患口腔炎的蛇低于健康雄蛇,且前两者呈显著性差异,后者呈极显著性差异。性激素检测结果显示罹患口腔炎的蛇血液睾酮和雌二醇含量均低于健康蛇,且均具极显著性差异。血细胞指标中,红细胞数量、红细胞分布均差、白细胞总数、淋巴细胞数量和淋巴细胞比率等均为罹患口腔炎的蛇高于健康雄蛇,且具显著性差异,但嗜中性粒细胞和淋巴细胞的比值(NLR)、中性粒细胞数量和比率、中间细胞数量及其比率均为患口腔炎的雄蛇低于健康蛇,且具显著性差异。结论:口腔炎不仅影响了主要代谢器官的器官系数的变化,而且血液多项指标和性激素水平也有明显差异。性激素含量的变化将对乌苏里蝮的正常生殖繁育产生不可忽视的影响。另外,NLR和红细胞分布宽度2个血常规指标可作为早期诊断炎症发生的首选参数。     

盐胁迫下栽培大豆黑农40不同器官中抗氧化酶活性的变化

通过对盐胁迫下栽培大豆黑农40的根、茎、叶等不同器官中主要的抗氧化酶活性的测定与分析,探讨了大豆耐盐性的机理.结果表明,黑农40叶片中的SOD、POD和APX活性水平明显高于根部和茎部.叶片中的POD和APX在高盐胁迫下的应答反应都比在低盐时快速.盐胁迫时间的延长引起根、茎、叶中的SOD和POD活性发生明显的下降,在高盐胁迫下这种下降比在低盐时更为急剧.     

高产小麦氮素积累及其与产量和蛋白质含量的关系

利用８个高产小麦品种,通过定期取样测定生育期各器官氮素含量,研究其氮素动态变化,进而探讨不同品种各器官氮素含量与产量和蛋白质含量的关系。结果表明,除籽粒外,不同品种各器官的氮素含量均随生育期进程而降低。其中茎秆的降低幅度最大,其次为叶片,再次为根系。叶片、茎秆及颖壳在收获时的含氮量与籽料产量呈负相关,而与籽粒蛋白质含相相关不显著。     

浉河流域不同来源鸭组织中硒和重金属元素的测定分析

对氵师河流域不同来源鸭组织样品中Se和Cd、Pb、Hg、Cr重金属元素的残留水平进行研究分析 ,结果表明 ,重金属元素在 3种鸭体内的残留量大小为 :野鸭 >放养麻鸭 >圈养麻鸭。并发现Cr与Se在各组织中的残留量相对较高 ,而Cd的残留量最低。从分布特征来看 ,Pb和Cd在羽毛中的残留水平最高 ,Se和重金属Hg、Cr在肝脏中的残留水平最高。羽毛和肝脏是重金属富集的主要目标器官 ,Hg和Cd等重金属残留水平与Se含量有一定相关性。     

豚草(Ambrosia artemisiifolia)不同器官与不同发育期中过氧化物酶同工酶分析

本文用凝胶电泳法测定了豚草根、茎、叶不同器官过氧化物酶同工酶酶谱,按其酶带相对迁移率(R_m),可分为11条酶带.豚草植株过氧化物酶同工酶与其他植物一样,有明显的器官特异性和阶段发育特异性.结果表明豚草茎叶中过氧化物酶酶谱在开花前后有明显的变化:(1)开花期较开花前酶带明显地增多;(2)开花期在主茎或叶片中,都会出现一条颜色较浅的,该器官花期特有的酶带;(3)豚草株体内一条主酶带(E 带)在开花期明显变浅.上述过氧化物酶同工酶的三种变化,为判断豚草植株体内开花前后生理生化变化提供了一种生化指标.     

不同条件巴山冷杉枝叶精油含量比较

运用传统的水蒸气蒸馏法,分析了巴山冷杉(Abies fargesiiFranch)不同种源、同一种源不同器官和不同年龄的针叶和枝条中精油的含量。结果表明,岷山地区巴山冷杉精油含量较高,3 a生的针叶和枝条精油含量最高,而且相互之间差异显著,同一年龄的针叶精油含量远远高于枝条。     

育成蛋鸡大肠杆菌病的病理组织学观察

[目的]深入了解鸡大肠杆菌病的病理组织学变化.[方法]试验采用流行病学调查、临床症状观察、病理剖检观察、实验室诊断和石蜡组织切片制作等方法对昌黎县某鸡场发生的一起蛋鸡以心包炎、肝周炎为主要特征的疾病进行诊断和病理组织学观察.[结果]试验分离到的病原菌为大肠杆菌;患病蛋鸡的病理组织学变化表现为:心脏呈心肌细胞变性、炎性细胞浸润;肝脏呈纤维素性肝周炎和坏死性肝炎;脾脏呈淋巴细胞减少、炎性细胞浸润;肺脏呈充血、淤血,肺房内存在红细胞;肾小球毛细血管透明变性;小肠粘膜上皮细胞脱落.[结论]该研究为鸡大肠杆菌病的诊断和防治提供了科学依据.     

Effect of Different Plant Growth Regulators on Callus Induction and in vitro Rapid Propagation of Wild Petunia Juss.

In this study,the seeds of wild Petunia Juss.were used as explants to investigate the optimal condition for tissue culture.Several different kinds and concentrations of growth regulators were adopted to produce more multiple bud clumps,callus or roots in this study.The experiments may provide experimental foundation for the rapid propagation technology and establishment of tissue culture system for wild Petunia Juss.