Hybridization in Acacia nilotica (Mimosoideae) complex

The variability in the Acacia nilotica complex is explained in terms of hybridization between A. nilotica subsp. indica and A. nilotica subsp. hemispherica . This is substantiated by the study of phenolic constituents, pollen fertility and intra-plant fruit variability. The hybrid populations may backcross with A. nilotica subsp. indica and A. nilotica subsp. hemispherica producing plants similar to A. nilotica subsp. adstringens and A. nilotica subsp. subalata respectively. The role of humans in directly and indirectly distributing the seeds of hybrid plants over vast areas and in creating the disturbed habitats suitable for plants of hybrid origin is discussed. Phenolic constituents of A. nilotica subsp. hemispherica and A. nilotica subsp. leiocarpa are shown to be distinctive. Probable hybridization between A. nilotica subsp. indica and A. nilotica subsp. cupressiformis is also discussed.     

Legal and Policy Dimensions of Coastal Zone Monitoring and Control: The Case in Ghana

Ghana is implementing a monitoring control and surveillance (MCS) system, which works within the network of the global position system (GPS), and is intended to provide an integrated ocean-monitoring regime and to enhance the capacity of the nation to effectively protect and utilize its ocean resources. This article reviews the need for and importance of the MCS system for Ghana. In addition, this article looks at the issues raised by the implementation of a MCS system in the context of coastal states' rights and the rights of other users of the sea.­     

Development of microsatellite markers for bambara groundnut (Vigna subterranea L. Verdc.) — an underutilized African legume crop species

Bambara groundnut is an indigenous African legume crop plant. It is largely grown by subsistence farmers, but can also be used as a cash crop to supplement family income. The fact that it is highly drought tolerant means that it has considerably potential to provide part of food security in regions of the world where water availability is a serious issue. As one part of the international effort to understand and improve this species, we report here the first 10 microsatellite markers derived from bambara groundnut.     

塔克拉玛干沙漠腹地冬季土壤呼吸及其驱动因子

利用Li-8150系统测定了塔克拉玛干沙漠腹地冬季(1月)土壤呼吸,分析了环境驱动因子对极端干旱区荒漠生态系统土壤呼吸的影响。结果表明:(1)冬季土壤呼吸日变化呈现出显著的单峰曲线,土壤呼吸速率最大值出现在12:00,为0.0684μmol CO2m-2s-1,凌晨04:00附近出现最小值,为-0.0473μmol CO2m-2s-1;(2)土壤呼吸速率与各层气温,0cm地表温度均存在着极其显著或显著的线性关系,且都具有正相关性;(3)土壤呼吸速率与5cm土壤湿度存在着较为明显的线性关系,该层湿度能够解释土壤呼吸的69.5%;(4)0cm地表温度对土壤呼吸贡献最大,其次是5cm土壤湿度;(5)以0cm地表温度、5cm土壤湿度为变量,通过多元回归分析表明:土壤温度-湿度构成的多变量模型能够解释大于86.9%的土壤呼吸变化情况;(6)研究时段内土壤呼吸速率的平均值是-1.45mg CO2m-2h-1。     

Identification of a component of the trail pheromone of the ant Pheidole pallidula (Hymenoptera: Formicidae)

ABSTRACT The poison gland of minor workers of P.pallidula. Nyl. contains 3-ethyl-2,5-dimethylpyrazine which induces trail-following in other workers, but does not account for the full trail-following effect of one worker's poison gland. No pyrazines were detected in major workers and their glands do not contain the pheromone.