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1.
为了解褐飞虱Nilaparvata lugens (Stål)侵害后水稻耐虫性与植物体内源激素关系,应用酶联免疫吸附法(enzyme-linked immunosorbent assay, ELISA)研究褐飞虱若虫侵害分蘖期超级培矮64S/E32和TN1,灌浆期协优963和TN1后根及叶片脱落酸(abscisic acid, ABA)含量变化.结果表明:褐飞虱侵害分蘖期超级培矮64S/E32和TN1后3 d,叶片ABA含量显著上升,ABA含量根冠比(根ABA/叶片ABA)显著下降;侵害后6 d,超级培矮64S/E32叶片ABA含量显著下降,根冠比显著上升;但TN1叶片ABA含量在褐飞虱侵害后3 d和6 d显著上升,根冠比显著下降.褐飞虱侵害灌浆期协优963与分蘖期超级培矮64S/E32变化一致,TN1在褐飞虱侵害后3 d叶片ABA含量显著上升,根冠比显著下降;侵害后6 d,叶片ABA含量、ABA含量根冠比均显著上升.由ABA含量变化百分比可见,分蘖期ABA含量变化幅度较灌浆期大;耐虫品种变化幅度较感虫品种大,持续期较感虫品种短;叶片变化幅度较根部大.褐飞虱侵害后,两种不同生育期两种抗性不同的水稻品种比较,耐虫品种叶片ABA含量先上升(3 d)后下降(6 d),ABA含量根冠比先下降(3 d)后上升(6 d);感虫品种叶片ABA含量持续上升(3 d和6 d),分蘖期ABA含量根冠比持续下降(3 d和6 d),灌浆期ABA含量根冠比先下降(3 d)后上升(6 d);耐、感虫水稻品种根部变化规律不明显.这些差别表明不同水稻(耐虫和感虫)品种受褐飞虱侵害后体内ABA含量变化规律不同.本研究结果对深入阐明水稻耐虫品种的机制具有重要参考价值.  相似文献   

2.
萨拉乌苏河流域化石智人的身高   总被引:1,自引:0,他引:1  
尚虹 《人类学学报》2004,23(3):196-199
采用股骨骨干下部横径等,根据中国汉族男女性长骨碎骨的身高推断回归方程推测有比较明确地层记载的萨拉乌苏河流域化石智人的身高。据此计算复原股骨长。采用一系列身高推测公式,得出该标本可能的身高范围并比较。该化石的身材比北京直立人高。与晚更新世智人相比,该流域化石智人的身材比山顶洞化石人类矮,比柳江化石人类高。  相似文献   

3.
水稻光合作用对加富CO_2的响应   总被引:2,自引:0,他引:2  
整个生育期经高Co(600μl/L)处理的5种水稻的PSⅡ原初光化学效率(Fv/Fm)与空气CO2(350μl/L)中生长的对照无明显的差异。高CO2下绿黄占3号,特三矮2号和普通野生稻叶片的平均光合放氧速率分别比各自的对照有所提高,而Ⅱ优4480和药用野生稻的光合速率低于对照。高CO2下生长的水稻叶片叶绿素含量和类胡萝卜素含量降低,生长后期的降解加快,并抑制了水稻的暗呼吸。绿黄占3号、特三矮2号和普遍野生稻的干物重在高CO2下较对照均有所增加,而Ⅱ优4480和药用野生稻的则下降。表明水稻不同种之间和种内的光合作用和生物量对高CO2的响应有一定的差异。  相似文献   

4.
温度对双低两用核不育水稻96-5-2S与培矮64S育性的影响   总被引:5,自引:0,他引:5  
在自然变温、人工控温及冷水灌溉条件下,比较研究了温度对双低两用核不育水稻96-5-2S与两用核不育水稻培矮64S育性影响的差异。结果表明:(1)当它们在雄性育性转换温敏感期1-12d平均自然日均温23.0-23.8℃的低温时,96-5-2S表现不良,套袋自交结实率为0,而培矮46S可育,套袋自交结实率为0.1%-4.5%;(2)在它们雄性育性转换温敏感期用22℃恒温处理5d,96-5-2S败育彻底,套袋自交结实率为0,而培矮64S可育,套袋自交结实率为10.7%;用17℃恒温处理6d,96-5-2S与培矮64S均可育,但96-5-2S套袋自交结实率(6.8%)显著高于培矮64S(2.5%);(3)在它们雄性育性转换温和不同温度的冷水串灌15d,水深维持在20cm左右,当水温为22-22.5℃时,96-5-2S不育,结实率为0,而培矮64S可育,结实率为18.5%;当水温为19.5-21.5℃时,96-5-2S与培矮64S均可育,但96-5-2S结实率(2.5%-45.1%)显著或极显著低于培矮64S(50.4%-56.9%)以上结果说明:导致双低两用核不育水稻96-5-2S雄性不育的起点温度与导致其生理不育的下限温度均低,其不育性比培矮64S更稳定,耐寒性比培矮64S更强,即可确保制种安全,又可确保自身繁殖,对加快两系法杂交水稻的发展步伐将起到重要的促进作用。  相似文献   

5.
用计算机为工具对32种生物钙调素(CaM)的四个钙结合区和两个疏水穴一级结构的保守性和变异性进行了数量分析。结果表明第一、二钙结合区(N端)比第三、四钙结合区(C端)更保守;即大多数物种CaM的第一、二钙结合区的同源性大于它们全序列间的同源性。而第三、四钙结合区则因亲缘关系和高低等生物而异,情况较复杂。N端疏水穴比C端疏水火保守,前者的同源性高于它们全序列间的同源性;而后者亦因亲缘关系及高低等生物而异规律不明显。  相似文献   

6.
用计算机为工具对32种生物钙调素(CaM)的四个钙结合区和两个疏水穴一级结构的保守性和变异性进行了数量分析。结果表明第一、二钙结合区(N端)比第三、四钙结合区(C端)更保守;即大多数物种CaM的第一、二钙结合区的同源性大于它们全序列间的同源性。而第三、四钙结合区则因亲缘关系和高低等生物而异,情况较复杂。N端疏水穴比C端疏水火保守,前者的同源性高于它们全序列间的同源性;而后者亦因亲缘关系及高低等生物而异规律不明显。  相似文献   

7.
四个籼稻(Oryza sativa L.)品种幼苗经1℃黑暗或光照250 μm ol·m - 2·s- 1处理后,抗冷的“桂山矮选3”比不抗冷的“青华6 号”幼苗存活率高,其子代是以“桂山矮选3”为母本的比“青华6 号”为母本的存活率较高。抽穗期剑叶经光照低温处理12、24 和36 h 后,光合作用是“桂山矮选3”和以“桂山矮选3”为母本的子代比“青华6 号”和以“青华6 号”为母本的子代下降较少。呼吸作用是前者比后者在处理12 h 时有明显升高现象。荧光参数Fv/Fo和Fv/Fm比值在处理24 h 时前者比后者下降明显,但在常温下恢复则是前者比后者明显较快。自然低温(寒露风)对叶绿素荧光的影响亦有相似的规律。对水稻后代的抗冷性倾向于母本进行了讨论  相似文献   

8.
矮岩羊夏季活动节律、时间分配和集群行为   总被引:3,自引:0,他引:3  
采用扫描取样法(每隔10 min进行一次扫描纪录,记录时间为5 min)对36只矮岩羊夏季昼间节律与时间分配进行了观察和研究,将矮岩羊行为划分为取食、移动、站立、卧息和其他行为等5类。结果表明,矮岩羊在夏季有3个取食高峰(6:00-9:00、10:00-11:00和16:00-20:00);1个卧息高峰(11:00-15:00)。在时间分配上,用于取食的时间最多(30.14±3.32)%,其次是卧息(26.44±3.59)%,站立(24.90±4.27)%,移动(15.73±1.26)%,而用于其他行为的时间,仅占(2.82±1.00)%。通过不同个体的比较,发现成年雄性用于取食和站立的时间最多,幼体用于移动和其他行为的时间最多,成年雌性用于卧息的时间最多。在矮岩羊集群方面,其集群类型有:混合群、母仔群、雄性群、雌性群和独羊,在夏季集群平均大小为(7.81±8.42)只,2~8只的羊群,占总群数的54.05%;不同集群类型的大小差异极显著(χ2=13.197,dƒ=3,P=0.004),混合群群体最大,而雄性群最小;雌雄比为1∶0.54,雌幼比为1∶0.26,成幼比为1∶0.17。这些都说明矮岩羊这类独特的行为和种群特征是长期适应金沙江干热河谷的结果。  相似文献   

9.
黄生 《生物多样性》1994,2(2):68-75
在台湾北部淡水河河口沼泽地带的秋茄(水笔仔),依其林冠高度略可分成高、矮两个亚种群(Subpopulation)。矮生秋茄长在地面较高的河边,高生秋茄则沿着一条潮溪,长在较低处。使用淀粉凝胶方法研究同功酶组合型式,判断这个地区的区域种群的遗传结构,发现生长在沼泽区内较干燥地带的秋茄和长在潮湿地带的秋茄遗传上的分化程度很低(Fst= 0.043)。这可能是因为区内的基因流传很顺畅,抵消了可能发生的种群分化。  相似文献   

10.
柳江化石智人的身高   总被引:3,自引:2,他引:1  
作者将柳江人的右侧股骨残段作了复原。根据华南人由肢骨测量身高的公式,如果柳江人股骨属男性,其身高为156.69±3.74厘米,比现代当地居民的平均身高偏矮。  相似文献   

11.
研究目前中国蒙古族主要族群身高情况。对中国蒙古族共13个族群4410例(男43%,女57%)成人身高进行了测量,分析蒙古族身高分型情况,探讨不同年龄组之间、不同族群之间的身高变化趋势。中国蒙古族男性为超中等身材,女性为中等身材。在13个族群中,男性是额济纳土尔扈特部身高最高,云南蒙古族身材最矮。女性是鄂尔多斯部身材最高,云南蒙古族身材最矮。3个年龄组间身高差异均具有统计学意义。男性、女性都以高型出现率最高,过矮型出现率和很高型出现率都很低。中国蒙古族身高与中国其他北方族群接近,高于7个中国南方族群,低于北方汉族,但高于南方汉族,低于日本人、韩国人。中国蒙古族13个族群间身高差异均具有统计学意义,在中国族群中蒙古族属于身材较高的族群。  相似文献   

12.
哈萨克族中小学生体质发育资料及身体发育指数分析   总被引:3,自引:2,他引:1  
本文报告了新疆阿勒泰地区7—18岁哈萨克族中小学生体质发育的调查结果。重点分析3456名城镇哈萨克族学生的体质发育资料。体质发育调查指标包括身高、体重、胸围、坐高、肩宽、骨盆宽六项,其增长幅度及变异度皆以体重为大。哈萨克族学生的身高不论男女,在多数年龄组小于国内同龄汉族学生,而体重则多数年龄组大于国内同龄汉族。本文还分析了哈萨克族学生的六项身体发育指数。  相似文献   

13.
To determine if there were consistent differences in growth, mortality, and recruitment on slopes and ridge crests in tropical montane forests, which could explain the (frequent but not universal) low stature of trees in the ridgetop forests, we analyzed data from long‐term plots in Jamaica (1990–1994; sixteen 200‐m2 plots, six on ridge crests and five each on north and south slopes). Mortality was higher on north slopes, while growth and recruitment rates were not significantly different among positions. Soil pH and effects of recent disturbance by Hurricane Gilbert were positively correlated with growth and recruitment, while slope angle and disturbance effects were the best predictors of mortality. The patterns we found in Jamaica, that growth and recruitment were not higher on ridge crests than slopes, are different than those found by Herwitz and Young in Australia where growth and turnover were greater on a ridge crest. Therefore, it is not possible at present to make simple generalizations about dynamics of ridge crest versus slope forests in the montane tropics.  相似文献   

14.
This paper analyzes the variation in the mean stature of adult males of a variety of population groups in India and examines the influence of geographical, climatic and ethnic factors on it. A considerable variation in mean stature has been found with respect to these three attributes. Variation "between" ethnic groups compared with "within" ethnic groups was found to be much more than that of geographical and climatic zones. Scheduled Castes (SC) and Scheduled Tribes (ST) populations have much low average height than that of General Castes (GC). Climatically dry and semiarid zones have a tendency to have higher stature than in the Monsoon areas. The mean height has been found to be the highest in north India. It is closely followed by west India. An interesting feature is that as one goes towards east and south the mean height gradually decreases. It is the lowest in islands. The mean heights have been regressed on geographical, climatic and ethnic factors, after converting these factors into binary variables. The regression analysis has strengthened the findings, that there is a highly significant relationship between height and geographical, climatic and ethnic factors.  相似文献   

15.
The co‐existence of very short stature due to poor chronic environment in early life and obesity is becoming a public health concern in rapidly transitioning populations with high levels of poverty. Individuals who have very short stature seem to be at an increased risk of obesity in times of relative caloric abundance. Increasing evidence shows that an individual is influenced by exposures in previous generations. This study assesses whether maternal poor early life environment predicts her child's adiposity using cross sectional design on Maya schoolchildren aged 7–9 and their mothers (n = 57 pairs). We compared maternal chronic early life environment (stature) with her child's adiposity (body mass index [BMI] z‐score, waist circumference z‐score, and percentage body fat) using multiple linear regression, controlling for the child's own environmental exposures (household sanitation and maternal parity). The research was performed in the south of Merida, Yucatan, Mexico, a low socioeconomic urban area in an upper middle income country. The Maya mothers were very short, with a mean stature of 147 cm. The children had fairly high adiposity levels, with BMI and waist circumference z‐scores above the reference median. Maternal stature did not significantly predict any child adiposity indicator. There does not appear to be an intergenerational component of maternal early life chronic under‐nutrition on her child's obesity risk within this free living population living in poverty. These results suggest that the co‐existence of very short stature and obesity appears to be primarily due to exposures and experiences within a generation rather than across generations. Am J Phys Anthropol 153:627–634, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   

16.
This paper offers new evidence on human stature in south China during the second half of the 19th century and early part of the 20th. It is based on the records kept by the Government of Canada of 97,123 Chinese immigrants who were required to pay an entry tax between 1885 and 1949. While the study population included both sexes and all ages from infancy to old age, it was largely male, with most ages falling between 12 and 50. The data reveal an increase of over 4 cm in the adult heights of both sexes between 1850 and 1930. They also indicate an upward trend of over 5 cm in the heights of adolescent males. The mean heights of male immigrants fall in the lower range of those reported in other studies of stature in south China. The rising trends contrast with a pattern of stagnation and decline reported in other recent findings but are consistent with other recent evidence of increasing economic growth, real wages, and life expectancy in south China during this period. One likely cause of improved well-being is the influence of the migrants’ remittances on socioeconomic change in south China.  相似文献   

17.
北京与重庆地区成人身高变化的研究   总被引:10,自引:3,他引:7  
1983年对北京、重庆两地市区和农村汉族685对父子和667对母女的身高和坐高进行了测量。结果表明,两地市区与农村的子女比其父母分别高2.4至4.0厘米(P<0.01)。在28.5年中,一代人平均增高3.35厘米。市区男女两代人都比农村的要高,而且市区年青人身高增加比农村的多。女青年身高增加比男青年的更多。北京人比重庆人高,而且北京年青一代身高增加比重庆人更多。重庆年青人上身增长比下肢多,而北京年青人则下肢增长多。结果还表明,身高相关系数为0.37—0.45,遗传力h~2值在0.6665—0.8217之间。  相似文献   

18.
肖瑜 《植物生态学报》1990,14(3):237-246
 本文初步研究了陕西省3个气候区域内7个地区的油松人工林生物量和生产力。根据55块标准地的295株伐倒木资料,建立了油松各器官生物量的估计方程。经研究比较不同区域油松人工林的生物量、年平均净初级生产量、现实生产量和叶片的干物质生产效率,结果表明,秦岭山地的油松林一般优于陕西北部的油松林,北亚热带和暖温带的油松林各项指标相差不大,但明显高于温带油松林。树干(带皮)生物量比例从南向北逐渐降低,树冠生物量比例从南向北逐渐增大。各调查区油松林分的林下植物种类不多,生物量约占群落总生物量的1%。林地凋落物重量在各地区之间差异很大,未分解层比例从南向北逐渐减小。经比较发现,陕西省大部分地区的油松人工林具有较高的生产力水平。  相似文献   

19.
Height and weight data for varsity football players from 1899 to 1970 were analyzed for evidence of a secular trend in such a specialized sample. Recent football teams ('61–'70) are, on the average, 2.6 inches (6.6 cm) taller and 35.3 pounds (16.05 kg) heavier than the teams at the turn of the century (1899–1910). The estimated trend over the 70 year span was 0.37 inches (0.94 cm) per decade for stature and 5.04 pounds (2.29 kg) per decade for weight. Unfortunately, it is not possible to partition these trends and obtain separate estimates for the “secular” effects and for those effects that might be attributed to “recruiting practices.” The observed trend for stature in football players corresponds with the upper limit of the estimated range for adult secular trend data for stature from Western European countries, and is greater than that reported for American young adult males both in college and in the general population.  相似文献   

20.
云南玉溪地区人口的性比   总被引:1,自引:1,他引:0  
对云南玉溪地区1982年人口普查时的性比(男:女100)进行了分析,发现:(1)玉溪地区总人口的性比(99.22)比全国的(106.3)低,0—4岁与5—9岁儿童的性比(103.45与102.9)也比全国的(107.15与106.24)低。(2)傣族的性比特别低,其0—14岁儿童的性比为98.54;回族的性比也较低,其0—14岁儿童的性比为101.22;汉族0—14岁儿童性比则为104.16。(3)“大跃进”与“国民经济暂时困难”时期出生的人(20—24岁)性比特别低,仅为92.30,而且按民族,县,及城、乡分别统计时均有同样趋势。这一情况在全国人口性比统计中也得到证实。作者估计,这可能是当时自然流产增多造成的。(4)玉溪地区解放以来总人口性比不断增高,1953年为88.70,1964年为94.94,1982年则为99.22。(5)城镇人口的性比(156.48)比农村的(95.86)高得多,这与全国各地区相同。  相似文献   

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