https://repository.sustech.edu/handle/123456789/16865 2026-04-06T08:25:25Z https://repository.sustech.edu/handle/123456789/16878 Title: Effectiveness of Timber Solar Dryers in Reducing Drying Time and Drying Defects in Comparison to Air Drying Authors: Nasroun , Tageldin Hussein; Elamin , Elamin Elhadi; Mohammed , Tagelsir Elnaim Abstract: An air drying shed and two green-house type of solar dryers of different designs were constructed at the Forest National Corporation sawmill at Suki town, Sennar State. Timber stacks in all three dryers consisted of 120 sunt (Acacia nilotica ) boards each stacked in 15 rows with 8 boards in each row..Three sample boards were selected in each stack for periodic measurement of moisture content (M.C.) and following the progress of drying in the three dryers. The three sample boards were placed at different levels of each stack. Each sample board was taken out at two days interval, weighed and returned to the stack. The dry-blub and wet-bulb thermometer readings were recoded and relative humidity worked out for each dryer. The moisture content was also calculated at two days interval. The results obtained showed that the average temperatures in the two solar dryers were significantly higher than that of the air dryer (ambient temperature). This resulted in a lower average final M.C. and lower equilibrium M.C. in solar dryers than in the air dryer. Solar dryer with high collector (SH) was the most efficient of the three dryers, with average final M.C. of 10.7% and equilibrium M.C. of 6.7%. This was followed by the solar dryer with low collector (SL) with average final M.C. of 11.9% and equilibrium M.C. of 7.5%, and lastly the air dryer with average final M.C. of 13.8% and equilibrium M.C. of 9.2%... The drying defects observed included minor warping incidents in the form of bowing which was more pronounced in air drying than in the solar dryers. Description: article 2013-01-01T00:00:00Z https://repository.sustech.edu/handle/123456789/16879 Title: Provenance Variation in seed germination, early seedling growth and water consumption of Hashab (Acacia senegal) on Clay Soils of Sudan Authors: Babiker , Imad-eldin A. Ali; Ahmed , Abdelgabar S.; Mahmoad , Abdelatief. E.; Warrag , Essam Ibrahim Abstract: The aim of this study is to assess the variability and differences in seed germination, early seedling growth and water efficiency among Acacia senegal provenances from the central clay plains of Sudan. Twelve locations throughout the clay part of the gum belt were identified as seed sources according to geographical discontinuity and differences in annual rainfall. Three irrigation intervals (every three, six and twelve days) were applied. To estimate the transpiration rate three bags in each cemented bed were kept without seedling and treated like the other bags in the same bed containing seedlings. All bags were weighed before and after irrigation allowing 5 minutes for drainage of excess irrigation water. Transpiration was calculated according to the irrigation treatments schedules from the differences in water loss between the bags with plants and those without plants. The irrigation interval had significant effect on germination percentage and seedling growth. The root/shoot ratio increased with the prolonged irrigation schedule. This indicated that the seedlings have tendency to allocate more dry matter to the root system and increase its growth and biomass as an adaptation against the dry soil conditions. However, there were some significant differences on the growth parameters in the interactions between the irrigation treatments and the hashab provenances. Most of the provenances showed close transpiration rate with some exceptions. The water use efficiency of the seedlings from the different provenances also varied and showed significant differences. This study concludes that seedlings of Acacia senegal have variability in growth performance. Also the seedlings growth is checked by the moisture availability in the soil and seedlings with high drought tolerance maximize the use of the moisture to build their biomass. Description: article 2013-01-01T00:00:00Z https://repository.sustech.edu/handle/123456789/16877 Title: The Effects of Farm Yard Manure (FYM) on Sodic Soil in Gezira-Sudan (Triticum aestivum L.) Production in Gezira-Sudan Abstract: On farm experiment was conducted at Istrihna block in the Gezira Scheme for two seasons (2003-04 and 2005-06) in a heavy sodic clay Vertisol to study the effect of farmyard manure, (FYM) and planting methods to improve water infiltration aeration, and yield of wheat. The experimental design used was a split plot design with three replicates. The sowing methods treatments (Flat and Ridge) were assigned to the main plots and the levels of FYM (0, 5, 10, 20 tonsha-1) to the sub plots. The infiltration test was measured using double ring infiltrometer method. Data on number of head per m2, thousand seed weight, plant height, biomass and grain yield were collected at harvest. The addition of the farmyard manure (FYM) improved the physical properties of the soil; it increased the depth of wetting front, cumulative infiltration and infiltration rate. Results of the study indicated no significance differences for planting methods on yield and yield components although the ridge sowing gave higher grain yield as compared to the flat sowing. The use of different levels of the FYM significantly increased biomass, grain yield, thousand seed weight, number of head per m2 and a plant height. The interactions of the planting methods and the manures showed significance differences for the grain yield. The highest grain yield (4.3 t ha-1) was obtained from the combination of 20 t ha-1 FYM with ridge planting method and the lowest grain yield (3.8 t ha-1) from the combination of 20 t ha-1 FYM with flat planting method. Description: article 2013-01-01T00:00:00Z https://repository.sustech.edu/handle/123456789/16876 Title: Prevalence and Etiology of Branch Wilt Disease (Nattrassia mangiferae) on Tree Species in Wad Medani Area, Sudan Authors: Abbasher , Abbasher A.; Husian , Majdolin M.; Zaroug , Mohamed S.; Zahran , Eldur B. Abstract: Branch wilt disease caused by Nattrassia mangiferae (Nattrass) has very wide host range. It attacks trees in forests, orchards, ornamental, and shade trees. It is one of the most hazardous diseases that spread in Wad Medani province, Gezira state, Sudan. In Sudan there is limited information about the disease occurrence. This study is therefore, conducted to study the prevalence of the branch wilt disease in Wad Madani and to study the pathogenicity and host range of the common N. mangiferae isolates in Wad Medani area. The results of the survey revealed that 29 tree species belonging to 15 families were found to be naturally infected. The highest magnitude of the disease was found in ficus (Ficus nitida Thunb.), cassia (Cassia nodosa Roxb.), and baobab (Adansonia digitata L.), where the disease incidence was 100% and the disease severity ranged from 55% to 60%.While the lowest magnitude of the disease was reported in Acacia spp. with 20 % disease incidence and 30% severity. The disease occurrence was confirmed in the different habitats surveyed with the highest disease incidence and severity reported from Attra with 100% and 53%, respectively. Whereas, the lowest incidence (30%-35%) and severity (20%) were recorded from Bankae forest and Hantoub. The laboratory studies revealed that there were 2 different isolates of N. mangiferae. The 1st one was isolated from ficus (Ficus nitida) and the 2nd was isolated from lime (Citrus aurantifolia Swingle.). In host range experiments using seedlings of 12 different tree species artificially inoculated by each isolate, the lime isolate successfully showed symptoms on 11 tree species. Only the seedling of Balanites aegyptiaca remained uninfected. While ficus isolate attacked only two tree species namely F. nitida and Eucalyptus citriodora Hook. Description: article 2013-01-01T00:00:00Z