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Drought resistance indices for screening of potato (Solanum tuberosum L.) genotypes
2019
Beyene, Z.K. | Mekbib, Firew | Abebe, T. | Asfaw, A.
In breeding for drought tolerance, availability of precise, cheap and easy to apply selection tool is critical. The aim of the present study was to identify potential screening tools that are useful for selection of drought tolerant genotypes in potato and select drought resistant potato genotypes. The study assessed sixty clones arranged in a 10×6 alpha lattice design with two replicates in a managed stress experiment. Two irrigation treatments were applied: fully watered non-stress and terminal drought, where the irrigation water supply to the crop was withheld after 50 % flowering to induce post-flowering stress. Stress indices were calculated based on tuber yield of genotypes in both stressed and non-stressed conditions. Identification of drought tolerant genotypes based on a single index was less informative as different indices identified different genotypes as drought tolerant. Hence, to determine the most desirable drought tolerant clones rank sum of indices, correlation, and bi-plot display of the principal component analysis was employed. The indices modified stress tolerance index based on non-stressed yield, Men productivity, Geometric mean productivity, Stress tolerance index, Harmonic mean, modified stress tolerance index based on stressed yield and Yield index exhibited strong association with both yield under stressed and non-stressed yield. These indices discriminated drought tolerant genotypes with higher tuber yielding potential both under stress and non-stress conditions. Genotypes CIP-398180.612, CIP-397069.5, and CIP-304371.67 were identified as drought tolerant. These genotypes could be potentially grown both under drought prone and potential environments and these selection attributes could help to develop climate resilient potato varieties.
Mostrar más [+] Menos [-]Fungicide Management of Faba Bean Gall (Olpidium viciae) in Ethiopia
2019
Wondwosen, Wulita | Dejene, Mashilla | Tadesse, Negussie | Kemal, Seid Ahmed
Various biotic, abiotic and socio-economic factors negatively affect the productivity of the crop. Among these, a new disease known as Faba bean galls (Olpidium viciae) has become a serious threat to faba bean production and productivity in highland areas of central and northern Ethiopia. Thus, field experiment was conducted in Lay Gorebela and Mush to assess the efficacies of fungicides for the management of faba bean gall under natural infection. Six fungicides were evaluated alongside control in randomized complete block design in three replications. Fungicides showed different levels of efficiency at both locations in both seasons. In 2014/15, the highest percent severity index and area under disease progress curve were calculated from control plots at both locations. At Lay Gorebela, higher grain yields were recorded from Metalaxyl 8% + Mancozeb 64% WP and Triadimefon 250 g/L sprayed plots whereas plots sprayed with Metalaxyl 8% + Mancozeb 64% WP gave higher yield at Mush. Similar trends in percent severity index and grain yield were observed with control treatment in 2015/16. Percent severity index and area under disease progress curve were negatively correlated with grain yield and positively correlated with each other at both locations and seasons. Partial budget analysis indicated as Triadimefon 250 g/L and Metalaxyl 8% + Mancozeb 64% WP were cost-effective. The chemical treatment could be used as a short-term control strategy, and a component in integrated management of faba bean galls
Mostrar más [+] Menos [-]Toprak Kökenli Bitki Patojeni Funguslarla Mücadelede Biofumigasyonun Kullanım Olanakları
2019
Sevilay Saygı | Muharrem Türkkan | İsmail Erper
Fusarium, Rhizoctonia, Sclerotinia, Verticillium, Armillaria ve Rosellinia gibi toprak kökenli bitki patojeni funguslar, birçok bahçe ve tarla ürününde bitki ölümlerine ve verim kayıplarına sebep olan kök çürüklüğü hastalıklarına neden olmaktadır. Kök çürüklüğü hastalıklarının kontrolünde dayanıklı çeşit kullanımı, ürün rotasyonu, solarizasyon, fungisit uygulamaları ve toprak fumigasyonu gibi çeşitli mücadele yöntemleri uygulanmaktadır. Metil bromide ve kloropikrin gibi fumigantlarla yapılan toprak fumigasyonu toprak kökenli fungusların kontrolü için kullanılan en etkili yöntemlerden biridir. Ancak bu kimyasalların çevre ve insan sağlığına olumsuz etkilerinden dolayı dünyada ve ülkemizde kullanımı yasaklanmıştır. Bu nedenle, yeterli hastalık kontrolü sağlayan ve ticari fungisitlerle rekabet edebilen alternatif yöntemlerin araştırılmasına ihtiyaç vardır. Biofumigasyon kimyasal mücadeleye alternatif yöntemler arasında değerlendirilmekte nematodlar, yabancı otlar ve bazı fungusların neden olduğu hastalıkların mücadelesinde oldukça etkili olup, entegre mücadelenin bir parçası olarak kabul edilmektedir. Toprak kökenli fungusların kontrolünde örtücü bitkiler, organik gübre ve biyokatı atıklar biyofumigant olarak değerlendirilmektedir. Bu çalışmada toprak kökenli fungusların kontrolünde biyofumigasyon uygulamaları ve biyofumigantların funguslar üzerindeki etki şekilleri değerlendirilmiştir.
Mostrar más [+] Menos [-]Economics of Maize and Bean Production: Why Farmers need to Shift to Conservation Agriculture for Sustainable Production
2019
Hillary Moses Omondi Otieno | George N. Chemining’wa | Charles K. Gachene | Shamie Zingore
Maize and dry bean are the most important food crops that feed over 85% of Kenyan households. However, the productivity of these crops is low due to the high costs of land preparation and weed control, soil infertility and limited soil moisture under the current conventional tillage system of production. A study was carried in Embu County and Kirinyaga County to determine the economic returns of a maize-bean rotation system under different tillage systems and fertilizer regimes. Maize was produced during the long rains under no-till with crop residue retention (NT+CR) and conventional tillage with no crop residue retention (CT-CR) and inorganic fertilizer regimes (NK, NP, PK, NPK, and NPK+CaMgZnBS). Dry bean was planted in the short rains in the same plots where maize under different nutrient management regimes and tillage systems had been grown and harvested. The trial was laid out in a split-plot design with the tillage method as the main plot and fertilizer as sub-plot. Economic performance was assessed using partial budget analysis based on labor data and prices of all inputs used during the production period. Grain yields were reduced by 10% to reflect farmers’ yield levels. Maize and dry bean grains were sold at the prevailing farm gate prices. Results showed that maize-bean rotation was KE 22,718 cheaper under no-till with crop residue retention (NT+CR) than under conventional tillage with no crop residue retention (CT-CR). On average, NT+CR recorded KE 29,569 higher net benefit than CT-CR. The NT+CR tillage recorded a benefit to cost ratio of 3.7 compared to 2.7 recorded under CT-CR tillage system. The NT+CR with NK combined was the most profitable treatment with a benefit to cost ratio of 4.92 for maize and 4.33 for maize-bean rotation system. Based on this research, combination of no-till with crop residue retention has the potential to improve economic status and alleviate poverty among resource-constrained farmers.
Mostrar más [+] Menos [-]Effect of Spirulina Biomass Fortification for Biscuits and Chocolates
2019
Oya Irmak Şahin
Microalgae can be regarded as an alternative and promising ingredient for food fortification or enrichment. Due to their nutritional composition, especially protein-high composition, they considered as a sustainable protein source for food. The aim of this work was to evaluate the Arthrospira platensis (Spirulina) dry biomass which is knowns as the greater protein and amino acid source in blue-green microalga, as innovative ingredient for newly formulated and produced biscuits and chocolates, for baby and children diets. All samples with Spirulina biomass showed significantly higher protein and amino acid content.
Mostrar más [+] Menos [-]Investigation of The Effect of Carvacrol Addition on The Change of Some Physicochemical and Bioactive Properties of Apple Juice Contaminated with Zygosaccharomyces bailii
2019
Kevser Karaman | Osman Sağdıç
In this study, the effects of carvacrol addition which is a natural preservative to apple juice samples contaminated with Z. bailii which is an osmotolerant yeast and shows resistance against high sugar concentration, low acidity, ethanol content and pasteurization process, were investigated on some physicochemical and bioactive properties and also changes in yeast numbers during storage period. For this purpose, the response surface methodology was applied and storage time (1-41 days), storage temperature (4-20°C), sodium benzoate amount (0-0.1%) and carvacrol amount (0-750 ppm) were selected as processing variables. Significant changes in physicochemical properties were observed due to yeast viability occurred during the storage of apple juice samples. The increase in the amount of carvacrol caused a decrease in the number of yeasts about 7 log level and prevented the spoilage of fruit juices. However, the brix value of the samples without carvacrol showed a decrease of 50% as a result of yeast activity and the fruit juice could not be consumed. Total phenolic content of the sample was in the range of 136.7-645.7 mg GAE/L and the lowest total phenolic content was determined for the run 11 having no carvacrol while the highest total phenolic content was for the sample added with the highest carvacrol level. As a result of the optimization process, it was observed that the deterioration activities of Z. bailii could be prevented to a great extent by the addition of maximum amount of carvacrol.
Mostrar más [+] Menos [-]Effects of Seasonal Factors in The Goats’ Reproductive Efficiency
2019
Usman Mir Khan | Ali Murad Khan | Umar Murad Khan | Zeliha Selamoğlu
Interest in goat farming is at its peak since the last decade of 20th century because the role of goat is well established in animal protein as well as in economic uplift of poor masses in the tropics and subtropics, but also constitutes an important component of traditional farming systems. Goat is a better option as farm animal in the tropics and subtropics as it can withstand dehydration and has better browsing habit which enables it to survive where cattle and sheep farming is difficult. Reproductive performance of does is of immense importance as contributing factor towards increased meat production and in finding out more prolific animals. This is the main factor affecting productivity of goats. Therefore, an improved reproduction rate will be an approach to increase in numbers. Reproductive seasonality represents a natural adaptation that provides important advantages for birth and offspring survival and development, as lambing/kidding coincides with good weather and maximum availability of forage. It is believed that photoperiod is the environmental factor other than food availability that determines the sexual activity in sheep and goat. This review paper focuses on the general aspects of seasonal factors influencing the goat’s reproductive efficiency.
Mostrar más [+] Menos [-]Antioxidant Activities of Eucheuma sp. (Rhodophyceae) and Laminaria sp. (Phaeophyceae)
2019
İlknur Ak | Gülen Türker
In this study, antioxidant activities of two macroalgae, Eucheuma sp. J.Agardh and Laminaria sp., J.V.Lamouroux used as food supplements were investigated. The antioxidant activity, free radical scavenging activity, the total content of phenolics, flavonoids and condensed tannins in extracts were determined. The IC50 values of the extracts of Eucheuma sp. and Laminaria sp. on DPPH scavenging activity was 2.26±0.03 mg/g and 2.63±0.03 mg/g of extract, respectively. The maximum total phenolic (5.31±0.04 mg GAE/g Ext.) were determined. According to our results, all extracts exhibited low radical scavenging activity when compared to the standards used, i.e. -tocopherol and butylated hydroxytoluene (BHT) with the inhibition percentage in the range of 48.45±0.06% (Eucheuma sp.) – 58.49±0.03% (Laminaria sp.). The highest flavonoid content was measured as 18.78±0.10 mg rutin/g of extract in Laminaria sp. The condensed tannins were not detected in Eucheuma sp. However, this value was measured as 6.24±0.60 mg CE/g of extract for Laminaria sp. According to our results, Eucheuma sp. and Laminaria sp., which are commercially sold in medicinal herb stores, are good sources of antioxidant components because of their phenolic and flavonoid contents.
Mostrar más [+] Menos [-]Affinity of Propofol to Human Serum Albumin and Cardiovascular Effects
2019
Betül Özaltun | Zeliha Selamoğlu
Propofol is used in general anesthesia and sedation. İt is an lipofilic agent and metabolize to inactive form in liver then excreted in the urine. In body it is turnover changes by human serum albumin amount. >97% of propofol is bound to serum albumin. So that hypoalbunemia changes propofol effects. Free form of propopol can pass all membrans such as the blood-brain barrier and the cellular membrane of the cardiac endothelium. Propofol may cause significant myocardial depression, decrease blood pressure and cause life threatining arytmias. Changes in the ratio of free and bound forms of propofol and albumin depending on the dose and duration of administration, the effects of this ratio on cardiac profile are discussed in this study. According to the findings, it was determined that the albumin affinity of propofol decreased in all dose groups in time. Since free HSA and free propofol ratio will increase, this situation is thought to affect the cardiac profile negatively.
Mostrar más [+] Menos [-]Çiftçinin Organik Tarıma Geçişinde Bilgilendirme Faktörünün Rolü: Kadirli Örneği
2019
Nermin Bahşi | Hasan Kurt
Bu çalışmada, çiftçilerin organik tarım bilgi düzeylerinin öğrenilmesi ve çiftçilerin organik tarıma geçme istekleri, organik tarıma başlamama nedenlerinin tespit edilmesi, organik tarıma yönelişe etkili olabilecek bilgilendirme konularının öğrenilmesi ve organik tarıma geçilmesindeki bilgilendirmenin önemini ortaya koymak amaçlanmıştır. Bu amaçla, Osmaniye ili Kadirli ilçesinde Çiftçi Kayıt Sistemine kaydı olan çiftçilerden tabakalı örnekleme yöntemine göre belirlenen 85 çiftçi ile yüz yüze görüşme yöntemi ile anket çalışması yapılmıştır. Yapılan çalışmada, çiftçilerin büyük oranda organik tarım kavramını bilmedikleri, genellikle gübresiz tarım ve doğal tarım olarak ifade ettiği belirlenmiştir. Üreticiler tarımsal uygulamalar konusunda bilgi kaynağı olarak ilaç bayilerini kullanırken, en rahat bilgi alabildikleri kaynağın ise kitle iletişim araçları olduğunu ifade etmektedirler. Çiftçilerin organik tarım konusundaki bilgilendirmeleri yetersiz buldukları da elde edilen önemli bulgulardandır.
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