Common bean (Phaseolus vulgaris) was domesticated ∼8000 years ago in the Americas and today is a staple food which has been consumed worldwide for its edible seeds and pods. In Ethiopia, it is one of the most important cash crops and source of protein in many areas. However, the national average yields are by far below the average yield reported in different countries. This low national average yield is due to poor soil fertility management and low nutrient availability associated with acidic soils. Most of the major common bean producing areas in Ethiopia is characterized by high rainfall and acidic soils which resulted in high nutrient fixation and low nutrient availability. Acidic soils are suggested as one of the most important soil factors which limit crop production and it is also phytotoxic which result in nutritional disorders and deficiencies of different soil nutrients for crop production. To cope with these production constraints, using of compost and lime are recommended. Lime is suggested to enhance soil health status through improving soil physic-chemical properties and neutralize the acid produced in the soil. In addition to this, it reduces Al+3 and Mn+2 toxicity and increases both P uptake in high P fixing soil and plant rooting system and improves common bean nitrogen fixation. Compost is also suggested as an option for improving soil fertility and increasing yield of common bean for poor farmers. The use of Compost in sustainable agriculture benefits farmers, growers, consumers and the environment in many ways. The proper combination of lime and compost application also has the potential of contributing to an overall increase of common bean yields due to the change in soil physio-chemical properties and enhance soil biological N fixation. This study sought to review the Effect of lime and compost application on the growth and yield of common bean in Ethiopia.

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Starch degrading bacteria are important for different industries such as food, fermentation, textile, and paper. The aim of this study is to isolate and characterize bacteria able to degrade starch from the rhizospheres of various plants at four sites located in Jimma University main campus. Collected soil samples were labeled as kobo (AJUMC), Avocado (BJUMC), Banana (CJUMC), and Cana indicia (DJUMC) respectively. Soil samples were serially diluted in sterilized peptone water; poured on sterilized starch agar plates, and incubated at 32 º C for 48h. The representative colonies shown different morphology was randomly picked up using the streaking method on nutrient agar. A total of 53 bacterial isolates were obtained from the soils rhizospheres. Microscopic characteristics showed that, among the 53 isolates 38 (72%) were Gram-positive bacteria, rod shaped, while 15(28%) were Gram-negative rod shaped bacteria. Based on the biochemical tests, the results revealed that, the 38 isolates were belonging to the genera Bacillus while the remaining isolates were belonging to the genera Pseudomonas. All isolates were catalase positive and only 15 isolates (Pseudomonas) were KOH positive and were negative to grow at 80 º C, while the 38(Bacillus) isolates have positive growth at 80 º C. The highest values of starch degrading index were the Gram positive bacteria isolates. The amylase activity was also carried with respect to time, temperature and pH of the media. The maximum activity of amylase at different temperatures from 35 to 45°C was recorded at 35°C(0.94 U/ml) within 24 h, while maximum activity at different pH from 5 to 9 was recorded at pH 7 (1 U/ml).

A convectional plant breeder faces the challenge of how to more effectively and efficiently perform selection and accelerate breeding progress to satisfy the requirements of changing demands for crop cultivars. However, with the development and advancement of molecular marker technology, the fate of plant breeding has shifted from year to year. Recently, different types of molecular markers have been developed, and advancements in sequencing technologies have greatly increased plant improvement. To further our understanding of molecular markers, several reviews have been published in recent decades. However, with the advancement of newly emerging technologies and techniques, the reviewers did not discuss several recently emerged technologies and techniques in plant breeding. Therefore, this article is intended to be reviewed as an overview of recent breakthroughs in DNA markers and their applications in breeding of crops for early and senior researchers with little or no experience with molecular markers. The progress made in molecular plant breeding, genetics, genomic selection, gene pyramiding, MAS, and gene mapping has contributed to a deeper understanding of molecular markers, provided deeper insights into the variability available for crops, and considerably supplemented current breeding techniques. Next-generation sequencing technologies assist in the identification of novel molecular markers for complex and unstructured populations through genotyping-by-sequencing, gene mapping, QTL mapping, and association mapping. Altogether, the classification of molecular markers and their potential application in plants are discussed.

Starch degrading bacteria are important for different industries such as food, fermentation, textile, and paper. The aim of this study is to isolate and characterize bacteria able to degrade starch from the rhizospheres of various plants at four sites located in Jimma University main campus. Collected soil samples were labeled as kobo (AJUMC), Avocado (BJUMC), Banana (CJUMC), and Cana indica (DJUMC) respectively. Soil samples were serially diluted in sterilized peptone water, poured on sterilized starch agar plates, and incubated at 32ºC for 48 h. The representative colonies showing different morphology was randomly picked up using the streaking method on nutrient agar. A total of 53 bacterial isolates were obtained from the soils rhizospheres. Microscopic characteristics showed that among the 53 isolates, 38 (72%) were Gram-positive rod shaped bacteria, while 15 (28%) were Gram-negative rod shaped bacteria. Based on the biochemical tests, the results revealed that the 38 isolates belonged to the genera Bacillus while the remaining isolates belonged to the genera Pseudomonas. All isolates were catalase positive and only 15 isolates (Pseudomonas) were KOH positive with negative growth at 80°C, while the 38 (Bacillus) isolates have positive growth at 80ºC. The highest values of starch degrading index were the Gram positive bacteria isolates. The amylase activity was also carried out with respect to time, temperature and pH of the media. The maximum activity of amylase at different temperatures from 35 to 45°C was recorded at 35°C (0.94 U/ml) within 24 h, while maximum activity at different pH from 5 to 9 was recorded at pH 7 (1 U/ml).