Elsadig A. Elhadi

Effect of incorporation of some wastes on a wheat-guar rotation system on soil physical and chemical properties

BackgroundImproving levels of organic matter in desert soils is necessary for their cultivation. A two-year study (2008 to 2010) was conducted on a sandy clay loam soil at the experimental research farm of the Omdurman Islamic University, Sudan to determine the effect of application of crop residue, sewage sludge, and humentos on selected soil properties in wheat-guar crop rotation system. Treatments were recommended inorganic fertilizer (125 kg N ha−1 and 92 kg P ha−1), recommended inorganic fertilizer with crop residues, crop residue, sewage sludge (10 t ha−1), humentos soil conditioner (200 L ha−1), and control.ResultsResults showed that soil physical properties were not significantly changed except soil water holding capacity. Application of crop residues with recommended fertilizer and sewage sludge for three seasons significantly increased cation exchange capacity and organic carbon by 57.15 % to 60.95 % and 61.0 % to 65.2 %, respectively. Moreover, combined application of crop residues with recommended inorganic fertilizer and sewage sludge had significantly decreased topsoil pH.ConclusionsThe results showed that judicious combined application of organic wastes with inorganic fertilizers could be a useful practice in sustaining fertility of poor sandy soils.Competing interestsThe authors declare that they have no competing interests.Authors’ contributionsRezig F.A.M she is the main author and did the field and laboratory job and drafted the manscript. Elhadi, E.A particpate in some field work, statstical analysis and participate in correction of the manscript. Mubarak, A. R He is the main supervisor and draft the proposal and participate in the correction of the manscript. All authors read and approved the final manuscript.

Effect of Growth Regulators on In Vitro Morphogenic Response of Boscia senegalensis (Pers.) Lam. Poir. Using Mature Zygotic Embryos Explants

The percent study describes the in vitro responses of mature zygotic embryos of Boscia senegalensis to different concentrations (0.0–5.0 mg/L) of 6-benzyladnine (BA), Thidiazuron (TDZ), α-Naphthalene acetic acid (NAA), and 2, 4-Dichlorophenoxyacetic acid (2, 4-D) supplemented on Murashige and Skoog medium (MS). The plant growth regulators (PGRs) were considerably affected the morphogenetic responses. BA produced adventitious shoots through two ways: direct organogenesis and auxiliary shoot formation. Both 2, 4-D and TDZ tend to produce callus, whereas NAA improve the development of embryos to seedlings. Maximum number of shoots/explant (14.8 ± 0.6) was obtained on MS medium supplemented with 3.0 mg/L BA. 67.0% of excised shoots were rooted either on 1/2 MS medium augmented with or without 0.25 mg/L IBA. The highest number of roots (1.2 ± 0.4) and root length (0.5 ± 0.2 cm) was produced on 0.25 mg/L IBA-containing medium. Regenerated plants were successfully acclimatized and transferred to the green house with 70% survival rate. All the plants appeared morphologically uniform with normal growth pattern. A rapid (30 days), efficient and without subculturing protocol for in vitro regeneration of B. senegalensis was developed.

Impact of organic residues and mineral fertilizer application on soil–crop systems I: yield and nutrients content

A five-season experiment was initiated to study the effects of the recycling of some organic residues on a soil–crop system of a guar–wheat rotation in a sandy clay loam soil located in the semi-arid tropics of Sudan. Treatments included: incorporation of crop residues alone after harvest (Cr+), with (FCr+) or without (FCr−) inorganic fertilizer, sewage sludge (SS) and humentos (H). Grain yield of wheat in FCr+ and Cr+ treatments was significantly higher than that obtained in FCr− and control plots by ∼22−62% and 116−119%, respectively. When crop residues were incorporated with inorganic fertilizer, the priming effect of crop residues on straw yield (106%) was almost double that of the priming effect of inorganic fertilizer (56%). The sustainable yield index of wheat straw dry matter for the control, crop residue, humentos, inorganic fertilizer, combined fertilizer and crop residue and sewage sludge was 28, 27, 8, 35, 21 and 38%, respectively. In general, N, P and K of straw dry matter (SDM) was in the order of FCr+ > FCr− > SS > Cr+> H > C. The findings suggest that repeated incorporation of crop residues with inorganic fertilizer and applications of SS could both sustain wheat performance in the dryland ecosystems.