Effect of Casuarina Crushed Nodules, Rhizospheric Soil and Leaves Compost on Salt Tolerance of <i>Casuarina equisetifolia</i>L. and <i>Casuarina obesa</i>Miq.

Soil salinization is one of the major causes of land degradation. In Senegal, this phenomenon continues to grow, making soils unsuitable for agriculture. To rehabilitate salty lands, one of the recommended strategies is the use of salt-tolerant plants. Among them, plants of Casuarinaceae family form a relationship with symbiotic microorganisms such as arbuscular mycorrhizal fungi and nitrogen fixing bacteria. It has been shown that symbiotic microorganisms play an important role in the establishment of tolerant plants in saline conditions (Djighaly et al., 2018). They improve plant performance and reduce transplant shock under salt stress conditions (Diagne et al., 2014). These microorganisms can be used as biofertilizers. However, inocula containing symbiotic microorganisms are either too expensive or unavailable in many developing countries. The aim of this study is to test alternatively affordable and low-tech solutions to promote symbiotic interactions such as Casuarina crushed nodule, Casuarina rhizosphere soil and Casuarina leaves compost that may contain symbiotic microorganisms and also nutrients such as N and phosphorus. Two species of Casuarina (Casuarina equisetifolia L. and Casuarina obesa Miq.) were grown in the greenhouse on sterile soil to which an amendment was added (Casuarina crushed nodules, Casuarina Rhizospheric soil or Casuarina leaves compost). Plants were subjected to saline stress. After four months of cultivation, they were harvested and morphological and physiological parameters were determined. Results showed that inoculation with Casuarina crushed nodules, Casuarina rhizospheric soil and Casuarina leaves compost improved growth, total dry biomass, total chlorophyll and proline contents of C. equisetifolia and C. obesa plants in salt stress condition. These positive effects were more important in C. obesa plants amended with Casuarina leaves compost. This study shows that Casuarina leaves compost can play an important role in the rehabilitation of saline soils by improving Casuarina trees performance in saline conditions.

Opportunities and Challenges of Rehabilitating Degraded Land in the Case of Cheha Woreda, Gurage Zone, SNNP Region, Ethiopia

The research was conducted in chaha wereda gurage zone SNNP region of Ethiopia.The aim of the study was to assess opportunity and challenges of degraded land rehabilitation.From the total population of the study area 20%(73)respondents were selected in order to achieve the objective of the study at hand,for the study both primary and secondary data was generated.The primary data collection was started with a preliminary survey followed by a key informant interview,focus group discussion,and household survey with questionnaires.The secondary data were collected from books,unpublished thesis,project report,and workshops,open ended questionnaire and checklists for interview.The households were selected using stratified sampling technique(Cochran)sample size formula the process of analysis of the study was carried out using qualitative description and quantitative analysis.The collected data were analyzed using descriptive statistics,the quantitative data were analyzed frequency and percentage when appropriate the qualitative data were discussed to substantiate the study.And the results were expressed in the form of tables and graphs.The findings of the study indicated that limited labor availability,high cost of maintenance.Lack of knowledge,soil conditions,high surfaces runoff,poor vegetation coverage,poor monitoring and evaluation,poor implementation and poor training on the technology use are major challenges.