松嫩平原林缘草地羽茅无性系构件结构与生长分析

以分蘖丛为单位,在生长季末期,采取大样本(n=30)随机取样的测定方法,定量分析了松嫩平原人工林缘草地的羽茅无性系构件结构及其数量特征之间的变化规律,为丛生型无性系植物生长策略的深入研究提供了科学积累。结果表明,在分株总数[(34.0±11.05)分株]中营养株占优势(83.3%)并显著高于生殖株(16.7%);在分株总生物量[(21.51±10.28)g]中生殖株占优势(66.9%)并显著高于营养株(33.1%)。羽茅无性系构件数量性状均存在较大变异。其中,变异系数最大的为生殖株分蘖节芽数达76.4%,最小为丛径27.6%;单株生产力生殖株是营养株的9.6倍,单株营养繁殖力营养株显著高于生殖株。羽茅无性系构件组分数量及其生物量均随着丛径的增加呈极显著的(P<0.01)幂函数异速生长,具有内、外部空间兼顾的补充和拓展策略。     

青稞品种(系)主要性状的聚类分析

为了发掘青稞的优异种质资源,考察了来自西藏各地区100份青稞品种(系)的主要农艺性状,以田间调查数据的平均值作性状比较进行数据统计分析和聚类分析。结果表明:全生育期的变异系数较低,株高、千粒重、穗长的变异系数中等,单穗粒重受环境影响的变异系数大;100份青稞品种(系)可分为3大类,第Ⅰ类共2份材料,其特点是株高较高,千粒重较高,穗长中等,单穗粒重较高,全生育期中熟的品种(系);第Ⅱ类共11份材料,植株矮小,千粒重中等,穗长最小,单穗粒重最小,全生育期较早的品种(系),第Ⅲ类中的87份品种(系)大多是株高中等,千粒重较小,单穗粒重中等,穗长最高,全生育期最晚的品种(系)。西藏地区青稞的农艺性状存在丰富的遗传变异,具有矮秆、穗数多、千粒重偏低等特点,可为今后的高产栽培提供理论依据。     

冬小麦形态特征与抗麦长管蚜的关系研究

1985—1986年在北京西郊利用23个冬小麦品种,研究了叶色、叶上绒毛、旗叶长和宽、旗叶长×宽、旗叶着生角度、株高、芒长等形态特征与抗麦长管蚜的关系。相关分析结果表明,叶色与感蚜性有极显著的正相关关系,但在时间序列上,相关关系减小,并在蚜虫发生高峰时消失;旗叶长及长×宽与感蚜性呈显著的正相关,且在蚜虫发生的前期作用较大;小麦叶上绒毛与感蚜性的关系不显著;芒长和株高都与感蚜性呈显著的正相关,但芒长作用在蚜虫发生前期,而株高则作用在蚜虫发生后期;旗叶着生角度在后期也与感蚜性呈显著的正相关。逐步回归分析的结果基本上与相关分析的结果一致,山此可揭示出形态特征综合决定抗蚜性的结论。     

罗曼褐父母代产蛋前期产蛋规律的分析

对1249只健康的23周龄的罗曼褐父母代种母鸡的产蛋情况进行观察,试验期67 d(至32周龄),目的在于了解产蛋前期,蛋用种鸡产蛋性能的变化规律。试验结果表明,随鸡群日龄的增大蛋壳颜色逐渐变浅,产蛋率和种蛋合格率逐渐上升,鸡群的死淘率在开始人工授精的前2周最高,双黄蛋率随产蛋率的上升而逐渐减小,双黄蛋平均重随产蛋率上升逐渐增大,到产蛋率达最高峰时开始变小,软壳蛋率和破蛋率随鸡群日龄的增大而逐渐减小,总蛋重及种蛋平均重随鸡群日龄的增大而逐渐增大。     

镉胁迫对茭白生长及产品残留量的影响

以茭白单季茭蒋墅茭和双季茭葑红早为试材,在土壤栽培条件下进行Cd2+浓度为25、50、100、200 mg?L-1的胁迫处理,测定了茭白生长过程中部分生理指标、形态指标及产品器官肉质茎中Cd2+残留量的变化。结果表明：分蘖前期和中期的生理生化指标及分蘖后期的形态指标,均表现为较低浓度的Cd2+胁迫促进生长、较高浓度则抑制生长;Cd2+胁迫浓度为25 mg?L-1时葑红早肉质茎中Cd2+残留量超标,但蒋墅茭在Cd2+胁迫浓度达50 mg?L-1时仍未超过无公害蔬菜产品国家标准的限量值。表明茭白对Cd2+的耐性较强,但品种间存在较大差异。     

不同品种沙棘种子特性的比较

通过对6个品种沙棘种子特性的比较,并对种子形态指标与千粒重的关系进行了统计分析。结果表明:(1)供试的6个品种中,千粒重的变化范围比较大,李沙4号最大(19.32g),明显高于其它品种。(2)6个品种种子的长度、宽度、厚度之间存在显著差异,辽阜1号和李沙4号的特征值明显高出其它品种。(3)沙棘种子的比重因品种不同而异。实优2号的比重最大,为1.057 3,实优1号的比重最小,比重与发芽率的大小顺序基本一致。     

Change of allometry between coarse root and shoot of Lodgepole pine (Pinus contorta DOUGL. ex. LOUD) along a stress gradient in the sub-boreal forest zone of British Columbia

Abstract

This transect study in 41–178 year-old stands of Lodgepole pine (Pinus contorta DOUGL. ex. LOUD.) in the southern boreal forest of British Columbia, Canada, analyses how site conditions modify the coarse root–shoot dynamics of trees. The allometric relationship between diameter growth of coarse roots and trunk is scrutinised for long-term site dependence, and short-term reactions to periodic climate conditions. Along a gradient from poor to rich sites, we analysed 54 trees. The sampling scheme provided two increment cores each from the three main roots and the shoot at breast height per tree. From the year-ring series, we calculated diameter time series for each shoot and each root. With these data, we show (1) that the trees’ coarse root diameter and shoot diameter are linearly related in a double-logarithmic coordinate system, thus representing constant allometry on the long run. Statistical analysis of these long-term trajectories reveals that (2) the relative allocation to coarse roots versus shoot is much higher on poor sites compared to rich sites. A closer look at the short-term reaction to stress events in the period from 1995 to 2000, where several dry years occurred, underpins that (3) a lack of water supply triggers biomass allocation in favour of coarse roots at the expense of shoot growth most pronouncedly on poor sites. Implications of this morphological plasticity for allometric theory, method development, tree and stand dynamics and carbon storage assessment are discussed.     

Effect of morphological traits of plant, head and seed of sunflower hybrids on house sparrow damage rate

Birds are important key pests of sunflower crops in many countries. In this study, 615 heads and 5429 seeds of 31 sunflower hybrids (single cross, three-way cross and introduced hybrids) were randomly selected and rates of bird damage were estimated at the Plant Breeding Research Institute of Karaj during the summer of 2004-2005. The Spearman correlation test showed a significant relationship between bird damage rate and some plant characteristics such as height of plant head above the ground (r = 0.100), inter-head distance or distance of heads from stems (r = −0.195), distance of petiole (nearest leaf) from head (cm) (r = −0.113), head diameter (r = −0.213), head angle to the horizon (r = 0.217) and seed density in sunflower heads (r = 0.320) (p < 0.01), but there was no significant correlation between bract length (r = 0.047), the sterile area to head surface ratio (r = −0.020), achene length (r = 0.267) and hull thickness (r = −0.002) and the rate of bird damage (p > 0.05). The Kruskal-Wallis non-parametric test showed significant differences of bird damage rate to hybrid plants, for head shapes, bract orientation in relation to the head surface and achene colors (p < 0.01) but no significant for stem hanging forms and degree of striping on the achene (p > 0.05). In conclusion, the sunflower heads suffering lower bird damage rates had traits such as greater diameter, flat and convex shape (edges curled outside), fewer angles to the horizon, more down-faced heads, open and longer bracts, longer distances between adjacent stems or heads, longer distance of petiole from head, and lower seed density. In considering the results of the present and previous studies, there was a degree of inconsistency of findings across all studies, but not for each sunflower trait. Future studies are still necessary for height of head above the ground surface, stem hanging form, head shape, bract length and orientation, sterile area ratio, seed density, achene length, color and striping, and hull thickness. Nevertheless, plant breeding trials should bear in mind these results to pursue the understanding of relevant characteristics in morpho-genetic studies in relation to bird damage.     

Mapping Spatial Patterns with Morphological Image Processing

We use morphological image processing for classifying spatial patterns at the pixel level on binary land-cover maps. Land-cover pattern is classified as ‘perforated,’ ‘edge,’ ‘patch,’ and ‘core’ with higher spatial precision and thematic accuracy compared to a previous approach based on image convolution, while retaining the capability to label these features at the pixel level for any scale of observation. The implementation of morphological image processing is explained and then demonstrated, with comparisons to results from image convolution, for a forest map of the Val Grande National Park in North Italy.     

猪前体脂肪细胞与肌卫星细胞体外联合培养

利用差速贴壁法分别纯化前体脂肪细胞与肌卫星细胞,按1∶10的浓度比接种混合培养。以单独两类细胞培养作对照,采用油红O染色和Desmin免疫组化染色鉴定,通过形态学观察和MTT比色绘制生长曲线研究细胞生长规律。结果表明,Desmin免疫组化染色观察肌细胞阳性率达97%以上,油红O染色计数诱导分化细胞比率大于60%;形态学观察发现,联合培养细胞接触汇合前形态呈梭形,接触后不规则重叠交织生长;充脂细胞呈现较晚,且数量稀少;HE染色可见多核细胞融合成肌管样结构;测定2～9d细胞生长曲线显示,联合细胞组增殖比率大于对照组,经历2～3d潜伏期、3～7d指数生长期后,并未与对照组同步进入平台期,而呈持续缓慢上升趋势。实验初步实现了体外猪前体脂肪细胞与肌卫星细胞的直接联合培养,并显示其与对照组生长特性存在差异。