Genetic Variation in Morphophysiological Characters of Seeds of Ceratoides arborescens,a Species Endemic to China

[Objective] The research aimed at investigating the variation in morpho-physiological characteristics of Ceratoides arborescens seeds from Inner Mongolia grassland.[Method] The seeds of six wild C.arborescens populations were collected from Siwangziqi,Xilinhaote,Keshiketengqi and Wengniuteqi in Inner Mongolia grassland;then a total of eight indicators of seed morphology and germination traits were determined,respectively.[Result] There was wide variation in seed traits among different populations of C.arborescens.The variation within the populations was higher than that among the populations,which meant that C.arborescens had a strong adaptability to environment pressure.The seed traits shared a significant positive correlation with each other（r0.931,P0.01）.The three germination-related indices including seed germination rate,germination index,vitality index had significant positive correlations with each other（r 0.836,P0.01）and with seed setting rate（r0.896,P0.01）,but shared weak correlations with morphological traits.There were significant correlations between pappus length and longitude,rainfall,as well as between seed width and temperature,rainfall（r0.801,P0.01）.[Conclusion] The research will provide reference for the seed breeding and collection of germplasm resource.We suggest that collecting seeds from various individuals from each populations will be the preferred strategy to initiate plant improvement program of the species and for gene conservation in seed banks.

Chemical Composition and Ruminal Digestibility of Ceratoides, a Salt-tolerant Perennial Plant,at Different Years

It has been proposed that salt-tolerant plant could be used as a feed resource for ruminants whereby salt would be removed from salinized land (Asian -Aust. J. Anim. Sci. (2002) 15:998 -1001). Ceratoides arborescens (Losinsk.) Tsien et C. G. Ma is known as a drought-and salt-tolerant plant,a kind of shrubs, growing in semi-arid land of Inner Mongolia. Because the covering effect of the perennial plant as a mulch over the soil might be expected, the optimum covering effect would be obtained after the growth period.The perennial plant produces seeds around summer and end its growth thereafter. Nutrient value of the perennial salt-tolerant plant, however,had not been reported in flowering period at different year. It is necessary to know the ruminal degradability of the plants of each growing year in order to determine the regimen to diet for ruminants. The present experiment,therefore,was undertaken to analyze the digestibility and chemical composition of Ceratoides arborescens as feed for ruminants.

新疆莫索湾南缘沙漠四种灌木空间异质性的对比

应用地统计学原理和方法,以莫索湾南缘沙漠为研究区,对心叶驼绒藜(Ceratoides ewersmanniana)、梭梭(Haloxylon ammodendron)、琵琶柴(Reaumuria soongorica)、沙拐枣(Calligonum leucocladum)4种优势灌木的空间分布格局进行定量研究。结果表明:心叶驼绒藜主要分布于丘底和丘坡,分布介于集群分布和均匀分布,变程31.44 m,各向同性;梭梭主要分布于丘坡和丘顶,呈自相关性很强的集群分布,变程89.03 m;琵琶柴主要分布在丘底,为中等程度的集群分布;沙拐枣在该区分布频度较低,各向异性,属于随机分布。该地区灌木分布受沙漠与绿洲环境的共同作用,心叶驼绒藜和梭梭在该地区适应良好,分布环境的互补性强,搭配建植防风固沙的生态效益明显。