EFFECTS OF THE ABUNDANCE OF PARTHENIUM HYSTEROPHORUS ON THE COMPOSITION AND DIVERSITY OF OTHER HERBACEOUS PLANT SPECIES IN SIMANJIRO RANGELAND, TANZANIA

Parthenium hysterophorus is an annual herbaceous plant native to tropical America; and an invasive plant in Africa causing distressing effects on natural flora. This study investigated the effects of P. hysterophorus on the composition and diversity of native herbaceous plant species in Simanjiro rangeland, Tanzania. Plant species count data were collected from 60 (1m2) quadrats. Using generalized linear models (GLM), the abundance of P. hysterophorus was regressed against the abundance and diversity of the native herbaceous plants. Also, Jaccard’s similarity index was used to compare species composition. Results showed that there were 14 herbaceous plant species belonging to 13 genera and 10 families in the study area. Parthenium hysterophorus was the most dominant species recorded. The abundance of P. hysterophorus has a substantial negative effect on the abundance and diversity of other herbaceous plant species. Moreover, Jaccard’s similarity index showed a slightly significant difference between the infested and non-infested areas. This finding suggests that P. hysterophorus has a substantial potential threat on other herbaceous flora which are sources of food and nutrients to livestock and wild animals in the area. Thus, integrated management strategies are required to control the weed from spreading to other nearby rangelands.

Molecular diversity analysis and DNA fingerprinting of cotton varieties of India

Genetic diversity was assessed in 48 popular varieties of tetraploid cotton from each cultivated zone of India using 68 SSR markers distributed across linkage groups. The markers produced a total of 144 alleles with an average of 2.19 per locus. The polymorphism information content (PIC) ranged from 0.04 to 0.57 with a mean of 0.23 indicating lesser diversity in the studied material. Jaccard’s similarity index based neighbourhood joining cluster analysis grouped the genotypes into three major clusters, each of which was further classified into sub-groups. Inconsistencies were observed between the clusters and known pedigree of the cultivars. A narrow genetic base was also revealed among the cotton cultivars. The SSR markers revealed a genetic similarity of 73% among the varieties studied. The DNA fingerprint developed using a selected set of 14 markers showed a probability of identical match of 2.47×10-3 with high goodness of fit (r2=0.86). The identified markers have great potential in DNA fingerprinting in cotton which in future could be integrated with DUS data descriptors for effective cultivar identification and differentiation.

A Study of Zooplankton Community in Dukan Lake, Kurdistan Region-Iraq, with a New Record of Craspedacusta sowerbii Lankester (1880) Medusa (Cnidaria: Hydrozoa)

A study of Zooplankton community has been carried out at four selected sites on Dukan Lake. Samples of water and zooplankton were collected monthly for the period from July 2015 to February 2016. Some physical and chemical properties of water were studied and the results showed that the air temperature were ranged from 0 to 36.16 °C, water temperature ranged from 2.83 to 34.66 °C, hydrogen ion concentration of studied sites were found to lie in alkaline side, it was ranged between 6.87 to 8.57, electrical conductivity ranged from 190.79 to 850.08 µs.cm­¹, turbidity ranged from 0.9-7.7 NTU, and dissolved oxygen from 3.3 to 6.8 mg.l-¹ while BOD5 were ranged from 0.53 to 34.66 mg.l-¹. Concerning to the zooplankton, 37 species were identified which belonged to Cladocera (48.38%), Copepod (43.28%), Rotifera (8.23%), Targigrada (0.08%) and Cnidaria (0.1%). The medusa of Craspedacusta sowerbii Lankester (1880) was recorded for the first time in Iraq. Regarding to zooplankton community, rotifer were ranged between 0 to 690.91 ind.m-3, Copepoda from 54.55 to 5927.27 ind.m-3 and Cladocera ranged from 18.18 to 6072.73 ind.m-3. According to Shanon-Weiner index, species diversity for zooplankton invertebrates was ranged from 0.325 to 1.091 bits/ind. Jaccard’s similarity index showed that the highest similarity was recorded between site (1) and site (4) with 40.74%.

FITOSSOCIOLOGIA DE DOIS TRECHOS DE FLORESTA OMBRÓFILA DENSA ALUVIAL EM SOLOS HIDROMÓRFICOS, PARANÁ, BRASIL

ResumoO presente estudo teve por objetivo caracterizar a estrutura de dois trechos de Floresta Ombrófila Densa Aluvial localizados no município de Guaraqueçaba, Paraná. Os aspectos vegetacionais foram relacionados a características ambientais como solos, relevo e profundidade do lençol freático. Para o levantamento fitossociológico foram alocadas 16 parcelas de 10 x 10 m em cada trecho estudado e amostradas todas as árvores com Perímetro à Altura do Peito > 15 cm. Ambas as áreas apresentaram uma associação entre Gleissolo Háplico e Gleissolo Melânico. No total foram identificadas 81 espécies, incluídas em 59 gêneros e 31 famílias. Myrtaceae foi a família de maior riqueza em ambos os compartimentos. O índice de similaridade de Jaccard foi de 29,6%. O índice de diversidade de Shannon (H’) foi maior para o trecho de menor saturação hídrica (H’= 3,13). Para o trecho de maior saturação hídrica H’ foi igual a 2,86 visto que poucas espécies são bem adaptadas aos solos temporariamente ou permanente saturados por água. Em razão da proximidade geográfica e das similaridades climáticas e pedológicas existentes entre os sítios estudados, concluiu-se que as diferenças estruturais e florísticas constatadas estão associadas às condições hídricas do substrato.AbstractPhytosociology analysis of two sites in the Dense Alluvial Ombrophilous Forest with hydromorphic soils, Paraná, Brazil. In the present study, we characterize the structure in two sites of Dense Alluvial Ombrophilous Forest, Guaraqueçaba, State of Paraná, Brazil. Aspects of the vegetation were associated to environmental conditions such as soils, topography and water table depth. For the phytosociological study, 16 plots of 10 x 10 m were established in each site and all trees with Perimeter at breast height > 15 cm were sampled. Both sites presented a mixture of Haplic Gleisoil and Melanic Gleisoil. A total of 81 species were identified, belonging to 59 genera and 31 families. Myrtaceae was the family of greatest richness in both areas. The Jaccard’s similarity index was 29,6%. The Shannon’s diversity index was lower in the site of greater water saturation (H´=2,86). However, few species are well adapted to environmental constraints associated with excess water in the substrate. Due to geographical proximity and similarities of climate and soil between the communities, the main factor determining the structure and floristic composition seems to be closely related to the condition of drainage of the soil.Keywords: Atlantic Forest; coastal plain; caxeta; water saturation.

Temporal and between-site variation in helminth communities of bank voles (Myodes glareolus) from N.E. Poland. 1. Regional fauna and component community levels

SUMMARYHelminth infections were studied in bank voles (Myodes glareolus) from 3 woodland sites in N.E. Poland in the late summers of 1999 and 2002, to assess the temporal stability of derived statistics describing the regional helminth fauna and component community structure, and spatial influence on the latter. Regional helminth fauna changed dramatically between the two years, primarily due to a fall in the abundance ofSyphacia petrusewiczibut was partially compensated for by an increase inMesocestoides lineatusandCladotaenia globifera. It was dominated by nematodes overall, but more so in 1999 than in 2002 when larval cestodes were more frequent. Most derived parameters for component community structure varied considerably between sites and the two surveys, the hierarchical order for sites not being maintained between surveys. They were susceptible to the disproportionate influence of three relatively rare, unpredictable species with the greatest overall aggregated distribution among hosts. Jaccard's similarity index was less influenced by the rare species, showing greater stability between sites and across years. In conclusion, temporal variation confounded any site-specific characteristics of the summary measures quantified in this study and their usefulness is therefore restricted to the years in which the surveys were conducted.