American Journal of Biotechnology and Bioscience

  • Influence of mercuric chloride and sodium hypochlorite on apical and axillary buds regeneration of Colocasia esculenta in tissue culture

    Taro (Colocasia esculenta L. SCHOTT) is a staple food in many southern countries and an ancient starchy crop consumed by more than 400 million people. It is treated by diseases and pests that affect seed availability. Thus, the techniques of in vitro culture mostly used to overcome the problem of seeds production meet enormous difficulties of infection and necrosis of the explants. This study aims to determine the optimal use of mercuric chloride and sodium hypochlorite for disinfection of apical and axillary buds of taro. For this purpose, three doses of sodium hypochlorite (8%, 10% and 12%) and mercuric chloride (0.08%, 0.1% and 0.15%) were used with three immersion times ( 25 min, 30 min and 45 min) for sodium hypochlorite and (5min, 7min and 10min) for mercuric chloride. A binary logistic analysis was performed to understand or predict the effect of different doses of NaOCl and HgCl2 on the behavior of apical and axillary buds of taro. The results showed that 8% sodium hypochlorite with immersion time of 25 minutes is favorable for the disinfection of both apical and axillary explants of taro. For mercuric chloride, only the dose of 0.15% is effective for apical bud survival. The present study offers an opportunity to make available the seed of taro through the organogenesis of the species without any risk of infection.

  • Effects of system benzylaminopurine-adenine sulphate in combination with naphthalene acetic on in vitro regeneration and proliferation of pineapple (Ananas comosus (L.) Mill var. comosus)

    In vitro micropropagation is now used in the production of healthy and homogenous pineapple planting materials. In order to increase the in vitro proliferation of pineapple, the synergetic effect of adenine sulphate (AdS) and benzylaminopurine (BAP) in presence or not of naphthalene acetic acid (NAA) was evaluated. Median axillary buds of crowns bursted 6 to 8 weeks old were cultured on Murashige and Skoog medium supplemented with BAP (0, 1 and 2 mg/l), NAA (0 and 0.5 mg/l) with or without AdS (40 mg/l). Five buds per treatment with four replicates were used. The addition of BAP to the medium stimulated regeneration (65 to 82%) and multiplication (3.04 to 6.13 plantlets/explant) which were further enhanced by the addition of NAA (98%; 6.42 plantlets/explant). AdS highly stimulated proliferation in presence of 2 mg/l BAP and NAA (14.96 plantlets/explant), plantlet mass (1.143g) but limited plantlet growth in height which was more induced in the absence of regulators (4.88 cm) and with AdS alone (5.63 cm). Thus, BAP is necessary for the proliferation of pineapple and the addition of 0.5 mg/l NAA to 2 mg/l BAP and 40 mg/l AdS optimizes the multiplication and growth parameters of pineapple plantlets. These results allow the mass propagation of pineapple’s homogeneous healthy planting materials.

  • Enhanced Expression of Dermal Aquaporins by Polysaccharide from Camellia sinensis

    The green tea polysaccharide was extracted from leaves of Camellia sinensis and hydrolyzed with enzyme. Skin moisturization effect of green tea polysaccharide was studied with 2D- PAGE analysis of epidermal hydration factors. Among up-regulated proteins extracted from Hacat cell treated with Green tea polysaccharide on 2DE gel, 5 aquaporins were observed. Among them the aquaporin 5 and 8 were increased 3.4 and 5.3 times respectively. The green tea polysaccharide was found to be effective for skin moisturization by enhanced expression of aquaporins.

  • Pre scaling up of bread wheat technology at Meket and wadla districts, North wollo zone

    In Ethiopia where the livelihood of the people is highly dependent on agriculture improving the production and productivity of wheat will be one of the important agenda for the agricultural sector. The national average of wheat in the country, which is 14 Qt/ha, is 24%, is still below the average of South Africa yield and 48% below that of the world’s (FAO, 2004). Demonstration on farmers’ fields at Jama and Meket districts in 2014 cropping season showed that the improved variety sora had a better yield advantage over warkaye, Tossa and local with a better resistance to yellow rust. Having this pre scaling up of bread wheat variety sora with it full package had been started at Meket and wadla districts of north wollo zone, Amhara region. A total of 15 Qt seed had been provided for 25 farmers on 10 ha of land. Two clusters have been organized at the respective districts. 295 qt of seed had been produced and promoted for local seed system on established seed producer cooperatives. Farmers and development agents had invited to visit clustered farms through inviting on field days and experience had been shared. Thus further scaling up and out should be carried out on the study areas and similar agro ecological zones. Capacity building and continuous follow up should be done for the established cooperatives for sustaining seed production.

  • Performance of Sesame Variety in moisture-deficit areas of Wollo, Ethiopia

    The field experiments was conducted at Kobo, Mersa and Chefa testing sites of Sirinka Agricultural Research Center in1999 and 2000 seasons for varieties adaptation and 2004 and 2005 seasons for genotypes selection. The experiments were conducted in randomized block design using three replications with the objectives of selecting adaptable variety for the lowland areas of Wollo. Analysis of variance for each environment revealed significant differences across the tested environments and from adaptation experiment variety Abasina is high seed-yielder (12.33 qt ha-1) and had low deviation from linear regression coefficient implying its stability for different environments. Therefore, Abasina was recommended for the lowland areas of northeastern Ethiopia and from genotype selection, Pungun yonggae showed stable performance and gave high seed and oil yield across the tested environments providing a seed and oil yield advantages of 99.0% and 94.9%, respectively over the standard check, while Kelafo 74 x C-22 sel 4 had specific adaptation to more favorable environments with a seed and oil yield advantages of 106.3 and 116.7%, respectively over the standard check. Therefore, based on their performances, Pungun yonggae and Kelafo 74 x C-22 sel 4 were officially released for production with the name of Borkena, and Ahadu respectively.

  • Demonstration of pearl millet technology at Raya kobo and Gubalafto districts, North wollo zone

    Pearl millet [Pennisetum glaucum (L.) R.Br.] locally known as “Bajra” is a nutritious course grain cereal. Globally, it is grown on an area of 34.6 million ha with annual production of 28.8 million tons. Demonstration of improved variety kola 1 was conducted in 2016/17 cropping season at Gubalafto and Raya kobo districts to create demand on the pearl millet technology to farmers and development agents and thereby to assess their reactions towards the introduced technology. It was conducted on two FTC’s from kobo and Gubalafto districts. Though all agronomic practices were employed equally at both locations the performance of the variety varies significantly. The variety Kola 1 gave mean grain yield of 3.2 ton/ha and 1.8 ton/ha at Kobo and Hara respectively. The study indicated that cultivating pearl millet in moisture deficit areas can be an alternative for sustaining food security. Farmers have shown great interest and promised to adopt the technology from their neighbor farmers. Therefore technology promotions and popularization on the study and similar agro ecological areas should be carried out in collaboration with stake holders.

  • Development of Rainfall Runoff Modeling in Matlab Environment

    The aim of this study is to understand the basic concept and parameters of rainfall-runoff model, and how that concept applies in model as well. And familiar with how to build/develop the models of rainfall-runoff, with more about the practical situations by considering corresponding different parameters according to the seasonal conditions (for example snowfall in winter season and its role according to the temperature), hydrological conditions of site also. Matlab is used as a tool for the developing this model. This type of models are very much useful to calculate the, how much water will enter in to deeper layers of sub-soil surfaces, when rainfall occurs and to calculate the total amount water losses in different forms (for example evaporation from land and transpiration from vegetation and trees) also. Get good experience while working with Matlab to develop the individual group model and while observing the already given scrip for example model to understand as well. While working with this exercise, got good questions about concept and parameters concerned for model development and had good discussion with in the working group and with available assistance/staff.

  • Orobanche Species distribution and severity of infested areas in south and north Wollo zones of Amhara region, Ethiopia

    Broomrapes (Orobanche species) are obligate holoparasitic flowering plant. Orobanche species are root parasite which can damage the crops underground before the weed emerged. Complete faba bean yield loss by this weed forced farmers to replace faba bean by cereal crops. The distribution of the weed is increasing annually. To obtain relevant information on the introduction and distribution of the weed, survey was conducted on randomly selected 72 farmers’ fields in 12 woredas in two zones, south and north Wollo. Four woredas, Kutaber, Dessie-zuria, Tenta and Mekidela are out of legumes production in south Wollo. In this survey, information was also gathered regarding farmers attitude and local control practices. Farmers practice is hand weeding but Orobanche shoots were emerged again in doubling and tripling. We cannot stop the dissemination of the weed due to the nature of dispersed agents such as wind, flood, farm machinery, crop seeds, animals, humans etc and the undulating features of the areas are all favorable agents to disperse the minute seeds of the parasitic weed and are beyond our capacity to control them, but we may bring a solution by multi-sector approach through developing resistant varieties using molecular breeding and with chemical control measures.

  • Different statistical methods to collect information about the adverse effects of climatic factors on cotton production

    This study investigates the statistical relationship between various climatic factors and overall flower and boll production. Also, predicting effects of climatic factors during different convenient intervals (in days) on cotton flower and boll production compared with daily observations. Further, collects information about the nature of the relationship between various climatic factors and cotton boll development and the 15-day period both prior to and after initiation of individual bolls. And, provide information on the effect of various climatic factors and soil moisture status during the development stage on flower and boll production in cotton. Evaporation, sunshine duration, relative humidity, surface soil temperature at 1800 h, and maximum air temperature, are the important climatic factors that significantly affect flower and boll production. The five-day interval was found to be more adequately and sensibly related to yield parameters. Evaporation; minimum humidity and sunshine duration were the most effective climatic factors during preceding and succeeding periods on boll production and retention. There was a negative correlation between flower and boll production and either evaporation or sunshine duration, while that correlation with minimum relative humidity was positive.