An endogenous growth inhibitor, 3-hydroxy-β-ionone. III. Its longitudinal gradients in the first internode of Phaseolus vulgaris

Dark-grown, 10-day-old bean seedlings (Phaseolus vulgaris L. cv. Morocco) were transferred to continuous light, and the resulting changes in growth rate and concentration of 3-hydroxy-β-ionone, an endogenous growth inhibitor, were monitored. The growth rate of the first internodes of the seedlings decreased rapidly and leveled off 20 h after onset of light. This plateau value was about 25% of the growth rate of the non-irradiated control. The concentration of 3-hydroxy-β-ionone in the internodes of the irradiated seedlings increased rapidly and reached a plateau value after 16 h. This increased level of the inhibitor was about 5 times the level in the non-irradiated control. The changes in the levels of the inhibitor in the internodes reflected the light-induced growth inhibition of the internodes. The longitudinal distribution of the growth inhibitor along the first internodes of the seedlings was closely correlated with the light-induced growth inhibition of the corresponding region of the internodes. The present results suggest that the endogenous growth inhibitor 3-hydroxy-β-ionone may play an important role in the inhibition by light of internode growth of bean seedlings.     

Pattern of spatial distribution of the common cabbage butterfly,Pieris rapae in a cabbage farm

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Contributions from the Entomological Laboratory, Kyoto University, No. 203.     

BODY SIZE DECLINES DESPITE POSITIVE DIRECTIONAL SELECTION ON HERITABLE SIZE TRAITS IN A BARNACLE GOOSE POPULATION

Analyses of more than 2000 marked barnacle geese (Branta leucopsis) in the largest Baltic colony, Sweden, showed that structurally large females generally produced larger clutches and larger eggs, hatched their broods earlier in the season, and produced more and heavier young than smaller females. In males, the corresponding relationships between reproductive parameters and structural body size were weaker or nonsignificant. Because structural body size traits have previously been found to be significantly heritable and positively genetically correlated, an increase in mean structural body size of individuals as a response to selection might have been expected. By contrast, we found that the mean adult head length and mean adult tarsus length decreased significantly in the largest colony by approximately 0.7 and 0.5 standard deviations, respectively, in both males and females during the 13-year study period. Environmental factors, such as the amount of rain in different years, were found to affect the availability of high-quality food for growing geese. As a consequence of this temporal variability in the availability of high-quality food, the mean adult structural body size of different cohorts differed by up to 1.3 standard deviations. Comparisons of mean body size of cohorts born in different colonies suggest that the most likely explanation for the body-size decline in the main study colony is that a density-dependent process, which mainly was in effect during the very early phase of colony growth, negatively affected juvenile growth and final size. We conclude that large environmental effects on growth and final structural body size easily can mask microevolutionary responses to selection. Analyses of environmental causes underlying temporal and spatial body size variation should always be considered in the reconstruction and prediction of evolutionary changes in natural populations.     

大明绿系选后代遗传多样性与高产特征分析

以内蒙古中东部地区61份绿豆品种大明绿系选后代为研究材料,通过对农艺性状的多样性及通径分析,明确了后代品系遗传类型及高产群体性状特征。结果表明,大明绿后代品系间性状差异显著,单株荚数变异系数最大为31.61%,其次为单株粒重28.05%,遗传多样性较丰富,多样性指数为单株荚数2.02,每荚粒数2.01,百粒重1.89,单株粒重1.96。后代品系主要有6种类型,各性状对单株粒重影响大小依次为:单株荚数>每荚粒数>百粒重>节数>株高。高产类型品系主要特征指标为单株粒重超过15 g,单株荚数超过30荚,每荚粒数8~10粒,株高48~60 cm,节数9~10节,百粒重可根据不同需求制定标准。     

小豆品种形态特征研究及综合评价

对30个小豆品种的11个形态性状进行了因子分析及聚类分析。结果表明,11个形态性状的变异系数在5.66%~26.38%之间,最大的为主茎分枝,最小的为荚长;将11个形态性状简化成生育期因子、单株荚数因子和粒重因子3个相互独立的主因子,这3个主因子提供了原始性状81.574%的信息;经综合评价优劣排序,来源于唐山本地的2个品种排在前2位,来自东北的材料位居最后;经聚类分析,30个小豆品种划分为4大类群,类群的划分与材料的地理来源有着密切的联系。因此在育种过程中,应把主茎分枝、单株荚数和生育后期作为首要目标性状进行选择,同时兼顾百粒重、株高等性状,选育出综合性状优良的新种质。     

利用微卫星标记分析我国13个地方灰羽鹅品种的遗传多样性

我国地方鹅品种具有很多优良性状,但长期以来由于没有形成科学的选育制度和培育方法,品种的遗传多样性没有得到完整保存。为了深入了解我国地方鹅品种的遗传结构,使之得到更好的保护和利用,作者选用31个多态性较高的微卫星标记(其中19个是首次用磁珠富集法从AFLP片段中分离),检测了我国13个地方灰羽鹅(An-sercygnnoides)品种的遗传多样性。利用等位基因频率计算出各群体的平均遗传杂合度(H)、多态信息含量(PIC)和群体间的遗传距离(DA)。结果表明:13个地方灰羽鹅品种中,平均多态信息含量为0.323–0.398,平均杂合度为0.4985–0.6727,各品种的杂合度都较高,最高的是狮头鹅(0.6727),最低的是雁鹅(0.4985)。用UPGMA法进行聚类分析的结果显示,13个品种被聚为4类:丰城灰鹅、武冈铜鹅、兴国灰鹅、狮头鹅、乌棕鹅、阳江鹅、马冈鹅、钢鹅、雁鹅聚为第1类;伊犁鹅自聚为第2类;长乐鹅、右江鹅聚为第3类;永康灰鹅自聚为第4类。本研究为鹅遗传育种提供了参考资料。