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1.
The following new species are described: Chamaecrista dunensis (Somalia), Acacia densispina (Somalia), A. flagellaris (Somalia), Tephrosia karkarensis (Somalia), T. scopulata (Somalia), Indigofera ancistrocarpa (Kenya), I. curvirostrata (Ethiopia), I. hiranensis (Somalia), I. karinensis (Somalia), I. kucharii (Somalia), I. nugalensis (Somalia), I. pellucida (Kenya, Somalia), I. sabulosa (Ethiopia, Somalia), I. sessilis (Somalia), I. ienuirostris (Somalia), Rhynchosia megalocalyx (Somalia), Crotalaria allophylla (Somalia), C. intricata (Somalia), C. warfae (Somalia), and Coronilla somalensis (Somalia). 2n = 22 is reported in Tephrosia karkarensis. Cassia somalensis, Acacia puccioniana, Sophora somalensis , and Crotalaria sennii are reduced to synonyms of respectively Senna hookeriana, Dichrostachys kirkii, Millettia usaramensis and Crotalaria boranica subsp. trichocarpa . Thirty-seven taxa are reported from Somalia for the first time, including Ptycholobium biflorum , known previously only from Southern Africa. Crotalaria pieropoda , known previously only from Socotra, is reported from Somalia and Oman. Neptunia oleracea and Vatovaea pseudolablab are new generic records for respectively Ethiopia and Oman. The fruits of Indigofera boranica are described. Vigna somaliensis and an allied species are discussed. Rhynchosia gansole is lectotypified and its flowers and fruits are described.  相似文献   

2.
Long-term climate–growth relationships, were examined in tree rings of four co-occurring tree species from semi-arid Acacia savanna woodlands in Ethiopia. The main purpose of the study was to prove the presence of annual tree rings, evaluate the relationship between radial growth and climate parameters, and evaluate the association of El Niño and drought years in Ethiopia. The results showed that all species studied form distinct growth boundaries, though differences in distinctiveness were revealed among the species. Tree rings of the evergreen Balanites aegyptiaca were separated by vessels surrounding a thin parenchyma band and the growth boundary of the deciduous acacias was characterized by thin parenchyma bands. The mean annual diameter increment ranged from 3.6 to 5.0 mm. Acacia senegal and Acacia seyal showed more enhanced growth than Acacia tortilis and B. aegyptiaca. High positive correlations were found between the tree-ring width chronologies and precipitation data, and all species showed similar response to external climate forcing, which supports the formation of one tree-ring per year. Strong declines in tree-ring width correlated remarkably well with past El Niño Southern Oscillation (ENSO) events and drought/famine periods in Ethiopia. Spectral analysis of the master tree-ring chronology indicated occurrences of periodic drought events, which fall within the spectral peak equivalent to 2–8 years. Our results proved the strong linkage between tree-ring chronologies and climate, which sheds light on the potential of dendrochronological studies developing in Ethiopia. The outcome of this study has important implications for paleoclimatic reconstructions and in restoration of degraded lands.  相似文献   

3.
The new species Acacia harala and A. mahrana , both from southern Yemen, are described and illustrated. A. harala belongs to A. subgen. Acacia and is known from the Abyan and Shabwah Regions, whereas A. mahrana belongs to A. subgen. Aculeiferum and is known only from the Mahrah Region.  相似文献   

4.
广西高峰林场相思树的真菌病害调查   总被引:1,自引:0,他引:1  
相思树是从澳大利亚引进的速生丰产林种,在广西以高峰林场为主要种植基地。经初步调查,不同相思树上发生的真菌性病害不同,马占相思树、厚荚相思树、直干相思树、纹英相思树、杂交相思发生炭疽病,其病原茵为胶孢炭疽菌(Colletotrichum gloeosporioides),在马占相思、直干相思、纹荚相思和杂交相思的叶片上只产生病原菌的无性阶段,而在厚荚相思叶片上可同时出现无性阶段和有性阶段;马占相思树和杂交相思树上发生的白粉病菌为白粉菌Oidium sp.,其中杂交相思白粉病发生普遍而严重,发病期多在3-5月;黑木相思树发生叶尖枯病,病原为异色拟盘多毛孢(Pestalotiopsis versicolor),一年四季均可发病;马占相思树干基部心腐病发生严重,造成木材的大量损失,病原尚未得到确定。本文对病害的症状特点、病原菌形态特征进行了描述。  相似文献   

5.
Lourdes Rico 《Brittonia》1987,39(1):130-132
A new species,Acacia sousae, from the states of Guerrero and Puebla is described and illustrated. A key for determination of the related species is given.  相似文献   

6.
The sinorhizobia isolated from root nodules of Acacia species native of Mexico constitute a diverse group of bacteria on the basis of their metabolic enzyme electromorphs but share restriction patterns of the PCR products of 16S rRNA genes and a common 500 kb symbiotic plasmid. They are distinguished from other Sinorhizobium species by their levels of DNA-DNA hybridization and the sequence of 16S rRNA and nifH genes. nolR gene hybridization patterns were found useful to identify sinorhizobia and characterize species. A new species, Sinorhizobium americanus, is described and the type strain is CFNEI 156 from Acacia acatlensis.  相似文献   

7.
A new species from Ethiopia and the northern Kenya, Plectranthus minutiflorus is described and illustrated.  相似文献   

8.
A new species from southern and Eastern Ethiopia, Plantago annua is described and illustrated.  相似文献   

9.
The new species Maytenus eritreana Sebsebe is described from northern Ethiopia. The new combination M. addat (Loes.) Sebsebe is made; this species occurs in the central and southern highlands of Ethiopia. The distribution of the two species is mapped.  相似文献   

10.
A new species of the genus Erythrochlamys is described: E. frulicosa from Somalia and Ethiopia. An interesting variation in E, leucosphaera is also discussed.  相似文献   

11.
James W. Grimes 《Brittonia》1992,44(2):266-269
A new variety, Acacia tenuifolia (Linnaeus) Willdenow var. producta is described and illustrated. The typification of the species is discussed. Acacia paniculata Willdenow and A. multipinnata Ducke are lectotypified and placed in synonomy of Acacia tenuifolia.  相似文献   

12.
Pešić V  Smit H 《ZooKeys》2011,(86):1-10
A new species of Atractides Koch, 1837 (Acari, Hydrachnidia) is described from Ethiopia. The world number of Atractides now tallies 297 species. The diversity of the genus Atractides in the Afrotropical region is briefly discussed.  相似文献   

13.
KORDOFANI, M. & INGROUILLE, M., 1991. Patterns of morphological variation in the Acacia species (Mimosaceae) of northern Sudan. A numerical taxonomic review has been carried out on the morphology of northern Sudanese Acacia species. Fifty-one characters were scored from 12 species sampled at 12 sites. There is evidence of large scale population variation. Within a single site species are distinct but a comparison of plants between different sites may obscure species differences. Each species has a peculiar local variant in each sampled site, even when sites are separated by only a few kilometres. The possible significance of this pattern of variation is discussed. Species complexes are delineated and useful species diagnostics described.  相似文献   

14.
Southwestern Saudi Arabia is described by a unique ecosystem and composed of apicultural landscapes where nearly 70% of the beekeeping activities are concentrated. However, this economically important resource is under continuous degradation threat urging restoration. Besides, profound information on the possible major biological components of future restoration; nursery level performances of the native plants, Acacia species is lacking. Hence, the study was aimed at evaluating performances of selected native Acacia species at nursery level as candidate biological tool for apicultural landscape restoration. For this, nine native Acacia species’ seedlings were prepared in accordance to appropriate techniques of nursery operations recommended for arid areas. Meanwhile, species were evaluated and compared based on some performance parameters. Accordingly, significant (P < 0.005) variations were observed among the species in shoot height, collar diameter, height to collar diameter ratio, number of leaves and seedling survival. Acacia origena Hunde, A. gerrardii Benth., and A. johnwoodii Boulos. were superior over the others in most parameters while A. etbaica Schiweinf. and A. asak (Forssk.) willd. were less vulnerable to chanced pathogens. Generally, nursery level performances of all Acacia species under experimentation were within the acceptable range and showed a remarkable score which may lead them to be considered as competent biological tools in the incorporation of the genotypes in apicultural landscape restoration efforts.  相似文献   

15.
Two new species of Violaceae are described: Rinorea friisii from the forests of SW Ethiopia and Hybanthus puberulus from the Borena bushland of S Ethiopia. The position of Viola erythraea within the V. cinerea complex is discussed.  相似文献   

16.
Six new species of Indigofera are described: I. eremophila Thulin from E Ethiopia, I. mooneyi Thulin from the highlands of SW Ethiopia, I. boranica Thulin from SE Ethiopia and NE Kenya, I. gyrata Thulin and I. ammophila Thulin from NE Kenya, and I. cana Thulin from north–central Ethiopia. I. cavallii Chiov., previously known only from the type from S Somalia, is reported also from NE Kenya.  相似文献   

17.
Three new species of Portulaca sect. Neossia are described: P. constricta from SE Ethiopia and Somalia; P. commutata , widespread in the Somali-Masai phytochorion of east and northeast Africa, and P. bulbifera from S Ethiopia and N Kenya.  相似文献   

18.
中国金合欢属植物的分类,分布及其区系的起源   总被引:7,自引:1,他引:7  
孙航  陈介 《云南植物研究》1990,12(3):255-268
本文对中国金合欢属(Acacia Miller)的分类、分布及其区系的起源进行了初步的研究;初步确立了本地区金合欢属植物约13种,3变种,其中包括2个新记录种,2个新变种;它们主要分布在西南及华南热带亚热带地区,尤以云南为最多。中国的金合欢届种类较贫乏,主要属Subgen. Aculeiferum,且几乎都是较原始的“A. pennata”体态,大都处于其分布区的边缘,种间关系较密切,区系比较年轻。该区系是中南半岛金合欢区系的一部分,除Subgen. Heterophyllum是来自澳洲外,其余最终通过印度板块来自非洲。  相似文献   

19.
The first species of Isoglossa known from Somalia, I. congesta is described om material from central Somalia and SE Ethiopia. It is related to I. parvifolia Rendle, occurring in E Ethiopia, but differs in the contracted inflorescences and long calyx lobes with long glandular hairs.  相似文献   

20.
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