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In this study, the success of single and combined releases of Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae) and Macrolophus melanotoma (Costa) (Hemiptera: Miridae) aganist Bemisia tabaci (Gennadius) (Hemiptera: (Aleyrodidae) were determined on greenhouse grown tomato plants that planted in net cages. The studies were conducted in spring growing seasons of the years 2009 and 2010. Experiments were established with four different treatments namely B. tabaci single (control), M. melanotoma single, E. mundus single, M. melanotoma+E. mundus combined releases with 3 replications (cage). In both years the B. tabaci, E. mundus and M. melanotoma were released 20, 6 and 0.5/plants, respectively. In order to determine population development of B. tabaci and E. mundus, leaf samples were taken at weekly intervals. In addition, numbers of immature and adult stages of M. melanotoma were counted by using visual control method on whole parts of 15 plants in each predator released cages. In the parasitoids released cages, the mean numbers of immature B. tabaci were not reached higher than 0.56 and 2.82 individuals/cm2 in 2009 and 2010, respectively. These numbers were found to be lower than control and M. melanotoma single releases. The highest immature B. tabaci numbers were determined in control treatments as 51.10 and 31.12 per cm2 in both years. Although M. melanotoma single release treatment reduced the whitefly numbers statistically compared to control treatment, it was not succeed as much as E. mundus. The results of this study showed that B. tabaci populations could be control without any insecticide treatments in greenhouse by using biological control programs that will be consisted with E. mundus and M. melantoma in Turkey. Source

The aim of this study was to determine biotypes of Bemisia tabaci (Gennadius 1889) (Hemiptera:Aleyrodidae) collected from different host plants in 2008 and 2009 growing seasons from Adana (Balcali) by using molecular identification methods. Samples were collected from cucumber, eggplants, cotton and soybean grown in Balcali at different dates. RFLP and SCAR-PCR methods were used to determine B. tabaci biotypes. All samples collected form cotton was determined as Q biotype. B biotype was determined only from four samples of totally collected 18 samples in 2008 while from one sample of totally collected 13 samples in 2009. Q type was determined as dominant in Balcali. Source

Mohamed M.Y.,Agricultural Research Corporation ARC

Sunflower (Helianthus annuus L.) is a new edible oil crop in Sudan. Many production constraints are responsible for fluctuation in its production and productivity. The main constraint is a lack of adapted, improved, highyield sunflower varieties. Farmers depend on imported seeds, which are usually unavailable and expensive. To reduce the cost of the seed and ensure seed supply at the optimum time, ten single-cross sunflower hybrids (SFH32, SFH36, SFH37, SFH310, SFH313, SFH314, SFH341, SFH345, SFH302 and SFH325) and the hybrid Hysun-33 (the check) were evaluated for yield potential and yield components. The experiment was laid-out in a randomized complete block design with three replications carried over five irrigated locations during the winter season of 2008/2009. There was considerable variation for yield and its components among the hybrids and locations. Significant differences were observed for hybrids (G), locations (E) and G × E interaction. All the genotypes gave high seed and oil yields under irrigated conditions. Three hybrids, SFH310, SFH313 and SFH341, performed better than Hysun-33 and the other genotypes across five environments. Stability analysis identified SFH310, SFH313 and SFH341 as the most stable hybrids for seed and oil yields, since their regression coefficients were close to the value of one (bi=1) and had the lowest deviation from regression (S-2di). In contrast, hybrids such as SFH32 and SFH37, with regression coefficients greater than one, were regarded as sensitive to environmental changes for seed and oil yields. The three promising hybrids were released last June for commercial production. Source

Abdelhalim T.S.,Agricultural Research Corporation ARC | Abdelhalim T.S.,University of Kassel | Finckh M.R.,University of Kassel | Babiker A.G.,Sudan University of Science and Technology | Oehl F.,Ecological Systems
Archives of Agronomy and Soil Science

A survey was conducted in 13 selected crops in the White Nile state, Central Sudan, to assess root colonization, spore densities and species richness of arbuscular mycorrhizal fungi (AMF) based on morphological aspects. For each crop, four samples were taken from one field. Additionally, an attempt was made to study the relationship between soil physico-chemical properties and AMF colonization rates, spore densities, species richness and other selected AMF diversity indices. The mean percentage of AMF colonization across all crops was 34%, ranging from 19% to 50%. The spore densities retrieved from the different rhizospheres were relatively high, varying from 344 to 1222 spores per 100 g dry soil with a mean of 798. There was no correlation between AMF spore densities in the soil and the root colonization rates. A total of 42 morphologically classifiable species representing 14 genera of AMF were detected without correlation between species richness in the soil and the spore densities. A hierarchical cluster analysis based on the similarity among AMF communities with respect to crop species overall showed that species compositions were relatively similar to the highest dissimilarities of about 25% dividing three of the four mango samples and the four sorghum samples from all other samples. © 2013 Taylor & Francis. Source

Malik A.A.Y.,Agricultural Research Corporation ARC | Karut K.,Cukurova University
Turkiye Entomoloji Dergisi

Populations changes of Bemisia tabaci (Gennadius 1889) (Hemiptera: Aleyrodidae) and its parasitism status were monitored on different host-plants in the Çukurova Region (Yüreǧir and Karataş districts) in 2008 and 2009. Samples were taken from cotton, cucumber, eggplant and soybean and pest numbers were counted in the laboratory. Each year, lower numbers of B. tabaci occurred in early July and increased to higher densities in August and September. Likewise, low parasitism rates by Eretmocerus mundus Mercet 1931 and Encarsia lutea (Masi 1909) (Hymenoptera: Aphelinidae) occurred in July and peaked in August and September. Er. mundus was observed to be more efficient on cotton, eggplant and soybean, but less on cucumber. The parasitism rates by Er. mundus on all host-plants were higher than those of En. lutea. While the highest parasitism rate of Er. mundus was found on soybean (73.94%) in the Yüreǧir district, that of En. lutea was on eggplant (24.3%) in the Karataş district in 2008. In 2009, while the highest parasitism rate by Er. mundus was on cotton (50.0%) in the Yüreǧir district, that of En. lutea was found on eggplant (20.0%) in the same district. These parasitism levels confirmed that Er. mundus and En. lutea are important parasitoids of B. tabaci in the Çukurova Region. Source

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