Plant gene technology: social considerations

The genetic modification of plants by gene technology is of immense potential benefits, but there may be possible risks. The advantages and social concerns of plant gene technology are discussed. Key Words: Gene technology, genetically modified plant, agriculture. African Journal of Biotechnology Vol.3(3) 2004: 156-15

Efficacy of cactus pear (Opuntia ficus-indica) varieties as a source of food and feed in Endamehoni district, Northern Ethiopia

Cactus Pear (Opuntia ficus-indica) serves as a source of food, feed, as well as a means of additional income to the people in northern Ethiopia. The species has different varieties with varied rate of productivity and palatability. This study was conducted to assess the food and feed value of the Cactus Pear varieties in Endamehoni District, northern Ethiopia. It was carried out in three “Tabias” (small administrative sub-districts) and nine sub-Tabias (also known as “Kushets”). These areas were purposively selected as they are well known for their good diversity of Cactus varieties. A total of one hundred and twenty households (n = 120) were randomly selected for interviews using a semi-structured interview. This was supplemented by information obtained through key informants’ interviews and field visits. The local farmers made the identification and characterization of cactus varieties traditionally based on the outstanding phenotypes like fruit characteristics, seed size and content, cladode descriptors and plant height. A total of 13 Cactus varieties were identified and recorded. To assess the food and feed value and to select the best used varieties in the area, preference rankings were made. It was found that not all varieties were equally edible and palatable. The most serious constraints in palatability were associated with fruit taste, fruit size, presence of spines, and hardness of seeds. The ethnobotanical study on palatability was supplemented by chemical analysis on Dry Matter (DM), Ash, Organic Matter (OM) and Crude Protein (CP) content from two-year-old young cladodes of four Cactus varieties (Kille, Wadwada, Magalla and Limo) that are more preferred for food and feed. The analysis of variance (ANOVA) showed significant differences in DM, OM and Ash content at p<0.05 (not at p<0.10). There was no variation in crude protein content amongst the varieties tested. From the results, it is concluded that propagation and use of varieties Kille, Limo, Magalla and Wadwada by farmers of the area is advisable.Keywords: Characterization, Cladode, Community, ethnobotany, fruit, palatability, preference, propagation, traditional knowledg

Metabolism of [14C]GA19 and [14C]GA53 by ecotypes of Betula pendula: the role of photoperiod

In many temperate woody species, short days (SDs) induced growth cessation has been shown to be prevented by the application of gibberellins (GAs). Evidence has also been forwarded for the influence of photoperiod on the metabolism of applied GAs. Continuing with this line of research, we studied the metabolism of 14C-labelled GA19 and GA53. [14C]GA19 and [14C] A53 were applied to the apices of the northern ecotype (67º N) and to the leaves of the southern ecotype (64º N) of Betula pendula Roth. under different photoperiods and at different times in order to compare metabolism during day and night periods. Assay of metabolites was made 10 h after application. Less than half of each applied GA was taken in by the plants and most of the activity was recovered from the application points. There was no clear effect of photoperiod on uptake of the GAs. After the HPLC analysis, most of the absorbed radiolabelled GAs were eluted as unmetabolised forms. However, significant levels of gibberellins A20, A29, A1, and A8 were recovered as metabolites of [14C]GA19 both in apical stems and leaves. In 1SD and 4SD-treated plants, there was less metabolism of [14C]GA19 compared to LD-treated plants. The difference was due to reduced metabolism of 14C]GA19 by SD-treated plants during the night period. On the other hand, metabolism of [14C]GA53 was very limited in all day-length treatments and during both, day and night periods. The most abundant metabolite was [14C]GA19 (10% of the activity in the samples). Key words/phrases: Conjugation, ecotype, gibberellins, metabolism, radioactivity SINET: Ethiopian Journal of Science Vol. 28 (1) 2005: 33–4

Global, regional, and national cancer incidence, mortality, years of life lost, years lived with disability, and disability-Adjusted life-years for 29 cancer groups, 1990 to 2017 : A systematic analysis for the global burden of disease study

Importance: Cancer and other noncommunicable diseases (NCDs) are now widely recognized as a threat to global development. The latest United Nations high-level meeting on NCDs reaffirmed this observation and also highlighted the slow progress in meeting the 2011 Political Declaration on the Prevention and Control of Noncommunicable Diseases and the third Sustainable Development Goal. Lack of situational analyses, priority setting, and budgeting have been identified as major obstacles in achieving these goals. All of these have in common that they require information on the local cancer epidemiology. The Global Burden of Disease (GBD) study is uniquely poised to provide these crucial data. Objective: To describe cancer burden for 29 cancer groups in 195 countries from 1990 through 2017 to provide data needed for cancer control planning. Evidence Review: We used the GBD study estimation methods to describe cancer incidence, mortality, years lived with disability, years of life lost, and disability-Adjusted life-years (DALYs). Results are presented at the national level as well as by Socio-demographic Index (SDI), a composite indicator of income, educational attainment, and total fertility rate. We also analyzed the influence of the epidemiological vs the demographic transition on cancer incidence. Findings: In 2017, there were 24.5 million incident cancer cases worldwide (16.8 million without nonmelanoma skin cancer [NMSC]) and 9.6 million cancer deaths. The majority of cancer DALYs came from years of life lost (97%), and only 3% came from years lived with disability. The odds of developing cancer were the lowest in the low SDI quintile (1 in 7) and the highest in the high SDI quintile (1 in 2) for both sexes. In 2017, the most common incident cancers in men were NMSC (4.3 million incident cases); tracheal, bronchus, and lung (TBL) cancer (1.5 million incident cases); and prostate cancer (1.3 million incident cases). The most common causes of cancer deaths and DALYs for men were TBL cancer (1.3 million deaths and 28.4 million DALYs), liver cancer (572000 deaths and 15.2 million DALYs), and stomach cancer (542000 deaths and 12.2 million DALYs). For women in 2017, the most common incident cancers were NMSC (3.3 million incident cases), breast cancer (1.9 million incident cases), and colorectal cancer (819000 incident cases). The leading causes of cancer deaths and DALYs for women were breast cancer (601000 deaths and 17.4 million DALYs), TBL cancer (596000 deaths and 12.6 million DALYs), and colorectal cancer (414000 deaths and 8.3 million DALYs). Conclusions and Relevance: The national epidemiological profiles of cancer burden in the GBD study show large heterogeneities, which are a reflection of different exposures to risk factors, economic settings, lifestyles, and access to care and screening. The GBD study can be used by policy makers and other stakeholders to develop and improve national and local cancer control in order to achieve the global targets and improve equity in cancer care. © 2019 American Medical Association. All rights reserved.Peer reviewe

Ethnoveterinary medicinal plants in rural settings of Bahir Dar district, Ethiopia

Most Ethiopian farmers and pastoralists rely on locally available plants to treat diseases of their domestic animals. Such knowledge needs to be recorded and transmitted to generations before it is eroded. In this study, the ethnoveterinary medicinal plants and the associated ethnoveterinary knowledge of farmers in Bahir Dar City Administrative Zone, Ethiopia, was documented. Seventy two informants were purposively selected from six study sites (kebeles). Semi-structured interviews, field observations and focus group discussions were used to collect ethnoveterinary information. Data were analyzed using quantitative approaches. A total of 69 plant species were used in the treatment of 36 livestock ailments. Plant species belonging to families Fabaceae and Solanaceae were frequently used. Roots of 32 species followed by leaves of 29 species were often utilized for remedy preparation. The majority of medicinal plants (72.5%) were harvested from the wild. Herbs constituted the dominant growth form used accounting for 40.6%. Most remedies were prepared in concoction/blend form. The majority of preparations (64.4%) were orally administered. Knowledge of medicinal plants is positively correlated with age of informants. In this study, Phytolacca dodecandra was found to be the most frequently used medicinal plant followed by Cucumis ficifolius. However, Cucumis ficifolius and Ipomoea simonsiana were the best and equally preferred species in the treatment of the most frequent disease locally known as “Kumegna.” It could be concluded that indigenous knowledge and the practice of using medicinal plants was still the major animal health care system in Bahir Dar rural community.

Studies on the Biology and Eco Physiology of Sesame Seed Bug, Elasmolomus Sordidus Fabricius, at Kafta - Humera Sesame Fields

The experiment was conducted in the plant protection laboratory of the Humera Agricultural Research Center to study the biology of sesame seed bug, Elasmolomus sordidus (Fabricius), Hemiptera: Lygaeidae. E.sordidus is considered as the most important harvest and post-harvest insect pest of sesame in North western Ethiopia. The rearing and other tests were conducted in the laboratory at 28-330C and 50 to 65% RH. The result of this laboratory investigation indicated that the mean egg incubation period was 5.4± 0.05 days while the total mean nymphal duration took 18.44±0.10. A mean adult lifespan of 20.24±0.19 days was recorded. The mean lifespan from egg to adult death was 44.08 days, which range from 32-54 days. The reproductive period was 7.08 ± 0.26 days and the peak laying period was on the first and second day of its reproductive days. Even though E.sordidus was present the whole year high outbreak was recorded at harvest (October) and continued up to January, which afterward declined until the next harvest time. &nbsp

Effect of red and far red light on inhibition of hypocotyl elongation in ecotypes of Betula pendula Roth.

Plants sense the quality, quantity, and duration of light signals and use them to optimise their growth and development. These signals are perceived by special light receptors of which the phytochrome pigment system is one of the most important for photo-morphogenetic responses. Using special diodes that emit monochromatic light, we studied the effect of red (R), far-red (FR) and R+FR combinations on hypocotyl elongation of latitudinal ecotypes of Betula pendula . Continuous R and FR inhibited hypocotyl elongation equally, but inhibition was higher when seedlings were irradiated by continuous R+FR. In all cases, inhibition increased with increasing irradiance, from 0.75 μmol m-2 s-1 to 76 μmol m-2 s-1. Moreover, seedlings treated by R or R+FR synthesised more anthocyanins than those exposed to FR. Accumulation of anthocynins increased with increasing irradiance up to about 19 μmol m-2 s-1

Woody Plant Diversity in an Afromontane Agricultural Landscape (Debark District, Northern Ethiopia)

Woody plants serve a wide range of economic, sociocultural, and ecological functions within traditional farming systems. Conservation of woody plant diversity within agricultural landscapes is therefore critical to farmers livelihoods. We studied the conservation status of woody plant species and associated indigenous knowledge of small-holder farming communities in the Debark District of northern Ethiopia. We conducted interviews with 60 informants and ran free-listing, preference ranking and direct matrix ranking exercises to measure the use of woody plants by farming communities. To compare farmers ranking of plants with their abundance in the landscape, we measured plant frequencies, densities, and diversity by undertaking a vegetation survey. Compared with 55 woody plants named by farmers during interviews, only 14 species were encountered in the vegetation plot data; most of the remaining species were rare and therefore located by targeted searches. We found relatively low indices of species diversity (H′ = 0.58) and evenness (J′ = 0.21), indicating the low conservation status of most woody plants. Trees and shrubs indigenous to the Debark landscape have been recently replaced by an exotic tree species (Eucalyptus globulus) with a more competitive growth rate, which is valued by farmers as an economic species. The most preferred indigenous tree species (e.g. Olea europaea ssp. cuspidata and Juniperus procera) have become increasingly rare, as reported in interviews and confirmed by direct field observation and vegetation plot data. Households have started planting some indigenous woody species; however, the vast majority of new plantings are E. globulus. Swift coordinated actions are necessary to prevent the rapid replacement of indigenous woody plant diversity by a monoculture of non-native trees. A community-based program for integrated ecological restoration of indigenous woody plant diversity would require support from local government agencies and non-governmental organizations

Traditional use of botanicals in reducing post harvest loss at crop stacking stage in Ethiopia: A case of Farta district

534-541Insect pests, rodents, and microorganisms comprise the larger proportion for the causes of post-harvest loss. The use of insecticidal/pesticidal and insect repellent plants is a deep-rooted tradition and cultural heritage in Ethiopia. This study was conducted to gather information on traditional botanical-based pest control practices by farmers of Farta district, northern Ethiopia. The study identified plants traditionally used as pesticides/insecticides during stacking crops at harvest time. The survey showed farmers are using about 31 species of plants for bottom layering during stacking of their crops. These plants are used as pesticides and insecticides although their level of utilization varied. The most commonly used and effective plant species were Croton macrostachyus Del., Eucalyptus globules Labill., Calpurnia aurea (Ait.) Benth., Vernonia myriantha Hook. f. and Laggera tomentosa (Sch. Bip. ex A.Rich) Oliv. & Hiern, of which C. macrostachyus is the most effective. The insecticidal effect of these botanicals was compared to the synthetic insecticide diazinon (0.1 %). Twelve hours after application of powders of C. macrostachyus, E. globulus, C. aurea and L. tomentosa, the mean mortality rate of termites was equivalent to that caused by diazinon. Further, the insecticidal effect of different parts of C. macrostachyus was compared. Leaves were the most effective. This calls for further identification and adoption of cost-effective and environmental-friendly indigenous/traditional botanical based pest control methods. Identification of active principles from these plants is highly desirable

Evaluation of morphological characteristics, yield and nutritive value of Brachiaria grass ecotypes in northwestern Ethiopia

Abstract Background A study was conducted to evaluate the effect of altitude and harvesting dates on productivity and nutritive value of three Brachiaria brizantha grass ecotypes (Eth. 13726, Eth. 13809 and Eth. 1377) in northwestern Ethiopia. A factorial arrangement of treatments was employed with a combination of three altitudes and three harvesting dates. The data collected consisted of plant height (PH), number of tillers, number and length of leaves and fresh yield. The yield and chemical analysis of forage samples were analyzed for dry matter yield, ash, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and acid detergent lignin. All data were subjected to analysis of variance procedures, with significance tested at P < 0.05. Results Results indicated that the highest plant height (PH) was recorded in all sites (low, mid- and high altitudes) by Eth. 1377 ecotype followed by Eth. 13726 ecotype (low and mid-altitudes) and in high altitude by Eth. 13809 ecotype. The highest DM yield was recorded by Eth. 13809 ecotype (7.26, 5.98 and 4.50) which was followed by Eth. 1377 ecotype (6.28, 4.68 and 4.30) at low, mid- and high altitudes, respectively. There was significant difference (P > 0.05) in DM yield with increasing harvesting dates for all ecotypes. CP content declined with increased harvesting date in all ecotypes [Eth. 13726 (16.33, 10.63 and 6.72), Eth. 13809 (13.87, 10.60 and 9.57) and Eth. 1377 (14.80, 10.15 and 7.86)] for 60, 90 and 120 harvesting dates, respectively. All ecotypes had the highest CP content at day 60 harvesting stage. Conclusions Although all ecotypes had potential as an alternative ruminant feed in all altitude areas in Ethiopia, highest CP and lowest NDF and ADF concentrations were recorded by Eth13809 ecotype. Its capability to grow at low rainfall maintaining high yields is an additional advantage over the other two. Thus, among the tested ecotype grasses Eth13809 showed outstanding potential as a forage plant especially in low altitude area of northwestern Ethiopia