Soil Chemical Analysis

Plant roots perform a myriad of functions right from the anchorage of plants to storage of reserve food material for the adverse weather. Roots forage around the soil for acquisition of ions and water and continually develop new branches. However, very little is known about the molecular mechanisms regulating root development and differentiation. We have endeavoured to decipher the genetic regulation of root formation in tomato by screening mutants defective in root development. We have isolated several mutants with altered morphology of roots. These mutants have been characterized for their phenotypes throughout the life cycle. In this report we show that for few of the mutants the vigour of plant is directly related to modification in the root structure. The potential utility of these mutants in understanding root development and also improving yield of tomato is discussed.

The International Atomic Energy Agency

The knowledge of environmental hazards resulted from natural radioactivity and human activities is very important for monitoring of environmental contamination. In this study, the environmental hazards due to the natural radioactivity and human activities in Tuban delta in Yemen were discussed and evaluated using gamma ray spectroscopy. Thirty soil samples were collected from the study area. The results showed that the mean activity concentrations of 238U series (226Ra), 232Th, and 40K were 16.83 ± 2.3, 24.76 ± 2.3, 646.48 ± 13 Bq kg-1 and 15.22 ± 1.5, 21.99 ± 2.1, 472.58 ± 10 Bq kg-1 for farm soil samples treated with organic and urea fertilizer and farm soil samples treated with urea fertilizer, respectively. The corresponding values were 19.53 ± 1.5, 24.46 ± 3, and 500.76 ± 17 Bq kg-1 for uncultivated soil samples. The activity concentrations of 137Cs showed a significant value in some uncultivated soil samples. Also, physical and chemical properties of some soil samples were discussed and evaluated. A Radiological parameter, an absorbed dose rate in air, and an annual effective dose were calculated and evaluated. The results were compared with those of literature.

Emran Eisa Saleh

Papers

Evaluation of Environmental Hazards Resulted from Human Activities andNatural Radioactivity in Tuban Delta in Yemen