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Investigation of Supported Producers within the Scope of Policies to Prevent Environmental Destruction Originated by the Agricultural Sector in Türkiye (Case of Cereal Producers in the Seyfe Lake Region) Full text
2022
Hasan Gökhan Doğan | Hüseyin Karaaslan
Environmental destruction is dimensioned as one of the most important issues that the whole world is dealing with in the third millennium. For this reason, various policy instruments are developed and put into practice, both internationally and nationally. Although these policies cover all production and consumption areas, they also come to the forefront in terms of the agricultural sector due to their strategic importance. Environmental Agricultural Land Protection Program (ÇATAK), which came into effect in 2006, has been implemented in order to prevent environmental damage in the agricultural sector in Türkiye. In this framework, the production practices of grain producers benefiting from ÇATAK program supports in the Seyfe Lake region of Kırşehir province were examined in environmental terms. For this purpose, 100 producers were drawn into the sample and a survey study was conducted. The obtained data set was made into cross tables, interpreted and suggestions were made. The results were statistically supported by chi-square analysis. Accordingly, although it was determined that the producers did not implement practices that would cause environmental destruction intensively, it was observed that they needed to adopt the right methods from the right sources in the use of fertilizers and pesticides. In addition, it has been determined that the state does not have comprehensive knowledge about the agricultural policy instruments it has implemented. For this reason, it is considered important to implement training-extension activities frequently and dynamically.
Show more [+] Less [-]Seroprevalence, Identification, and Pathology of Salmonellosis in Selected Poultry Farms at Barishal District of Bangladesh Full text
2022
Shampa Rani | Khondoker Jahengir Alam | Shib Shankar Saha | Md. Mostafizur Rahman | Md. Shah Alam
Salmonellosis is a critical challenge in commercial poultry farming. This study aimed to calculate seroprevalence, identify Salmonella spp., and its pathological investigation from January to December 2019. One hundred fifty (150) serum samples and fifty (50) cloacal swabs from apparently ill and healthy birds were collected in this study. Seroprevalence was observed by serum plate agglutination (SPA) tests. The tentative diagnosis of salmonellosis was made based on history, clinical signs and bacteriological studies. Salmonella spp. was further confirmed using an automated microbiological method (VITEK®2). Post mortem examination was done in apparently sick birds, and gross and microscopic pathological lesions were investigated and recorded in a datasheet. The overall seroprevalence of salmonellosis was 42.67% in commercial chickens. Age wise prevalence of avian salmonellosis showed significantly highest infection rate in adult layers (≥ 45 days old) 65.31%, then 40.74%up to 45 days. In case of broiler, the prevalence rate in 0-10 days, 11-20 days, and 21-35 days were 13.63%, 44.12%, and 16.67%, respectively. Seasonal influence showed significantly highest proportionate prevalence of salmonellosis during summer 66.15%in comparison to winter 25.00% and rainy 24.44% seasons respectively. In bacteriological study, 12 samples were positive for Salmonellae among 50 cloacal samples. Out of 12 positive samples 5 samples were selected for the automated microbiology system VITEK® 2, and only two samples were confirmed as Salmonella gallinarum. Gross pathology of representative organs revealed bronze-colored enlarged liver, hemorrhages in the spleen and lungs, and hemorrhages in the ovary with stalk development. Microscopically, multifocal nodule formation and infiltration of inflammatory cells in the liver parenchyma and marked congestion with inflammatory cells in the spleen, hemorrhage and congestion in the lungs and intestine.
Show more [+] Less [-]Prospects of Kiwi Production and Marketing in the Advancement of Household Economy in Dolakha District Full text
2022
Santoshi Malla | Lal Bista | Rojina Sapkota
This study entitled was conducted in 3 places of Dolakha district namely Boach, Jiri and Bigu. The study was conducted during 20thjuly to 6th September 2017. The main aim of this study was to find out whether kiwi farming is improving household economy of people living there (i.e. Boach, Jiri and Bigu) using various tools such as questionnaire, discussion, direct observation and review of literature. A total of 60 households were randomly selected for the study. Both male and female were found to be involved in kiwi cultivation. About 60 percent and 40 percent of respondents were male and female respectively. 20 percent respondent were illiterate, 38 percent people have primary level education, 17 percent were people having secondary and S.L.C. level education respectively, similarly, the respondent completing Inter were 8 percent. Kiwi was the major cash crop in the study area and the widely used variety in the study site was Monti. Agriculture is the major occupation followed by Government job, Business and others. 47 percent were involved in agriculture, 30 percent were involved in government job, 13 percent have Business and 10 percent follow other jobs like (Teaching, Driving, Abroad). Among 60 respondents 50 percent were cultivating kiwi in 1-5 ropani of land and minimum was 12 percent who cultivated kiwi in above 15 ropani area. Training related to kiwi cultivation was also given to the respondent. 47 percent respondents were trained in kiwi cultivation and 53 percent were not trained about it. Training was organized and conducted by DADO and some other organization who were concerned about agriculture. Kiwi was mostly sold to nearest local market by the farmers themselves. Kiwi cultivation was also helping farmers in economic part. The study shows that there is an improvement of household economy and livelihood by kiwi farming.
Show more [+] Less [-]The Solution of Multicollinearity Problem via Biased Regression Analysis in Southern Anatolian Red Cattle Full text
2022
Hatice Hızlı
The aim of this study is to investigate the effectiveness of biased estimation methods, principal component regression (PC) and ridge regression (RR) methods, according to unbiased the least squares (LS) method, against the multiple linearity problem (multicollinearity) encountered in regression methods. For this purpose to fit a model on account to predict body weight from some body measurements of 32 South Anatolian Red Kilis (SAR) cattle of different ages. R2, RMSE, MSE, and CV were used as the goodness of fit criteria for the performance of the models. According to these criteria respectively, 0.9970, 0.0224, 0.0005, 0.0099 for LS; 0.9970, 0.0224, 0.0005, 0.0099 for PC; and 0.9876, 0.0455, 0.0021, 0.0201 of k=0.02 for RR gave the best fit values. According to these results, LR and PC showed the best fit. But RR and PC techniques from biased prediction techniques provided more consistent, valid, stable, and theoretical expectations than LS technique, since LR did not provide the necessary assumptions.
Show more [+] Less [-]Evaluation of The Visual Landscape Quality of Parks: The Case of Serik/Antalya Full text
2022
Rifat Olgun
The visual perception of landscapes is expressed as seeing the qualities of the landscape. This level of perception varies depending on the socio-cultural and economic structure of the people and the environment in which they live. The fact that the environment in which people live has a variable visual structure also constantly affects their landscape perception. Parks are one of the important urban landscape areas in cities. The existing structure of the parks located in the urban landscape areas affects the visual perception value of these areas on the users. The aim of the research is to evaluate the visual landscape quality value of the parks in the city of Serik in the direction of user opinions. In this context, the photographs of the selected parks within the boundaries of the research area were taken from certain points. The questionnaire form prepared with these photographs was applied to the park users on a voluntary basis. The data obtained from the questionnaire forms were digitized and analyzed. Within the scope of the analysis, the data belonging to the socio-demographic structure of the participants and the answers they gave to the propositions about the parks were determined by descriptive analysis (frequencies and descriptives). Whether there was a statistically significant difference between the sociodemographic structure of the participants and their answers to the propositions was analyzed with parametric tests (independent sample t-test and one-way analysis of variance). At the same time, the relationship between the visual landscape quality assessment criteria of the parks was examined by Pearson Correlation Analysis. The results of the analysis show that the features of the parks due to their planning, design and maintenance affect the visual landscape quality values. In this direction, suggestions have been developed to increase the visual landscape quality value of the parks.
Show more [+] Less [-]Determination and Evaluation of Field Adequacy by Ankara Göksu Park Users Full text
2022
Elif Nur Doğan | Sertaç Güngör
It is one of the biggest city parks of Ankara, which people can easily reach in daily use, walking, jogging, sitting, picnicking, playing etc. Göksu Park, which provides opportunities for activities such as, is built on the old Susuz pond in Eryaman. The park was opened in 2003. In this study, a 3-stage method was applied to determine and evaluate the area adequacy of the park. In the first stage, the first picture selection was made with the team of landscape architects in the park, using the nominal group technique, among the photographs taken in the area, obtained from the municipality and received the most likes from social media accounts with many followers. In the second stage, the criteria for the evaluation of field adequacy with the Delphi technique were determined by consulting the faculty members in the Department of Landscape Architecture, Faculty of Agriculture, Ankara University, who were selected as experts on the subject. Then, using the observation and comparison tables, the survey questions were prepared and after the application of the survey to the visitor group and park staff, as the third step, the survey data was based on whether the difference between the observed frequencies (OF) and expected frequencies (EF) was statistically significant with the help of SPSS 25 statistical program. Chi-square independence analysis, which is a test, and linear regression analysis were performed. By counting the frequencies, the relevant photographs will be examined and the relationship between density and field adequacy has been interpreted. With this study, it will contribute to the plans and designs of new projects so that the green areas and parks that people need due to the increasing population and urbanization can be used adequately in the future.
Show more [+] Less [-]Some Morphologic Characteristics of Central Anatolian Merino Sheep Full text
2022
Selçuk Seçkin Tuncer | Sedat Behrem | Yunus Arzık | Mehmet Kızılaslan
This study aimed to investigate the body weight and some body measurements in Central Anatolian Merino sheep regarding ages and to carry out a comparative analysis between them. The study included a total of 60 animals aged 2, 3 and 4 years. The sheep were fed daily with hay, vetch, alfalfa and limited amount of concentrated feed (400 g head-1) until the pasture period, and pasture grass and mixed grass-clover hay during the pasture period. The live weights of the sheep of different ages in the farms were measured with a digital scale, and some body size were measured using a measuring tape and a measuring stick. When the live weight and chest circumference values of the 4-year-old sheep were compared with the data obtained in the other age groups (2 and 3 years old), and it was statistically significant, chest width and rump height values were found to be similar to those in the 3-age group. There were significant correlations between live weight and chest circumference, between withers height and rump height and significant correlations between live weight and chest width, body length with rump height, chest width with chest depth. In addition, significant correlations were found between live weight and chest depth, and between withers height, body length, and chest depth. Present findings revealed that the Central Anatolian Merino sheep can be beneficial in the development of meat-type sheep breeding.
Show more [+] Less [-]Changes That May Occur in Temperature, Rain, and Climate Types Due to Global Climate Change: The Example of Düzce Full text
2021
İsmail Koç
Changes That May Occur in Temperature, Rain, and Climate Types Due to Global Climate Change: The Example of Düzce Full text
2021
İsmail Koç
Global climate change is defined as a process that affects all living things and ecosystems globally and is claimed as the most critical problem of the current century. Turkey, which is shown as one of the most affected countries by this process, is among the “countries at risk.” It is stated that the temperature will increase throughout the country until 2100, and this increase may reach 6 ºC. In order to determine the possible effects of global climate change, it is necessary to predict how the climate structure and basic parameters may change. From this point of view, this study is aimed to determine the change of temperature and precipitation, climate types (according to De Martonne, Lang, and Emberger climate classification) which are the most critical climate parameters until 2050 and 2070 in Düzce, one of the important cities of our country. The current situation and possible changes in 2050 and 2070 have been compared using RCP 4.5 and RCP 8.5 scenarios. As a result of the study, the temperature, precipitation, and related climate types would change significantly throughout the province of Düzce, and this change will show itself as a significant temperature increase and change in precipitation regime. In addition, a shift in climate types towards continental climate types is predicted until 2070. In order to avoid the destructive effects of global climate change, it is recommended to take measures on a sectoral basis.
Show more [+] Less [-]Características de la caña de azúcar asociadas con toneladas de caña por hectárea y sacarosa (% caña) Full text
2015
Viveros Valens, Carlos Arturo(Centro de Investigación de la Caña de Azúcar de Colombia, CENICAÑA) | Baena Garcia, Diosdado(Universidad Nacional de Colombia, Sede Palmira Facultad de Ciencias Agropecuarias) | Salazar Villareal, Fredy(Centro de Investigación de la Caña de Azúcar de Colombia, CENICAÑA) | López, Luis Orlando(Centro de Investigación de la Caña de Azúcar de Colombia, CENICAÑA) | Victoria K, Jorge I(Centro de Investigación de la Caña de Azúcar de Colombia, CENICAÑA)
En las etapas iníciales del proceso de selección clonal en caña de azúcar (Saccharum spp.) se realiza la selección indirecta para las variables toneladas de caña por hectárea (TCH) y porcentaje de sacarosa. Esta selección indirecta puede aumentar su eficiencia en la medida que se precise mejor el conocimiento acerca de la naturaleza y la magnitud de las asociaciones existentes entre las características de interés y entre éstas y los indicadores de productividad. El objetivo del presente trabajo fue estimar las correlaciones genéticas entre las variables de tipo agronómico (factores causales) y las de rendimiento (variables de respuesta), además descomponer su magnitud mediante análisis de sendero. Se evaluaron cinco caracteres de interés en caña de azúcar (altura, diámetro de tallos, población de tallos por metro, TCH y sacarosa (% caña)) en cinco localidades de la zona semiseca del valle del río Cauca para 17 variedades y dos testigos (CC 85-92 y MZC 74-275) en plantilla utilizando un diseño experimental Latice. Para estimar los coeficientes de correlación genética y de sendero (‘path coefficient’) se utilizó el software GENES. El análisis mostró que para obtener variedades con alto TCH y alta sacarosa (% caña), primero se deben seleccionar clones con altura superior que la variedad testigo CC 85-92 (334 cm) para asegurar un contenido alto de sacarosa y posteriormente hacer un segundo tamizado por tallos gruesos de diámetro mayor que el testigo (32 mm) y alta población de tallos igual o superiores que el testigo (14 tallos/m) | In the initial stages of clonal selection, indirect selection for variables tons of sugar cane per hectare (TCH) and sucrose (% cane) is used, based on some agronomic traits associated with TCH and sucrose (% cane). This indirect selection can increase efficiency to the extent that better knowledge about the nature and magnitude of the associations among the characteristics of interest required and, between the latter and productivity indicators. The aim was to estimate genetic correlations between agronomic traits (causal factors) and performance variables (response variables), also decompose its magnitude by path analysis. Five characters of interest, cane length, diameter, stalk population per meter, TCH and sucrose (% cane) were evaluated in five locations in the geographic area of the semi-dry valley of the Cauca River to 17 varieties and two witnesses (CC 85-92 and MZC 74-275) on plant-cane using Latice experimental design. To estimate the genetic correlation coefficients and path coefficients (path coefficient) the GENES software was used. The analysis showed that for high TCH varieties and sucrose (% cane) must first be selected clones carried high above the control range 85-92 CC (334 cm) to ensure a high sucrose content, and then you can make a second screening by thick stems of larger diameter than the control (32 mm) and high stalk population equal to or higher than the control (14 stems/m)
Show more [+] Less [-]Farklı Gübre Uygulamalarının Buğday Bitkisinin SPAD Değerleri, Yeşil Aksam Kuru Madde Verimi ve Azot Konsantrasyonu Üzerine Etkisi Full text
2021
Kemal Yalçın Gülüt
Farklı Gübre Uygulamalarının Buğday Bitkisinin SPAD Değerleri, Yeşil Aksam Kuru Madde Verimi ve Azot Konsantrasyonu Üzerine Etkisi Full text
2021
Kemal Yalçın Gülüt
Son yıllarda gerek tarımsal ilaçların gerekse kimyasal gübrelerin bilinçsizce kullanımı bitkisel üretimde artışın yanında kalitesiz ve insan sağlığını tehdit edecek ürünlerin ortaya çıkmasına neden olmuştur. Söz konusu sorunlara karşı sürdürebilir tarım ve değişik tarım alternatifleri konusunda çalışmalara ihtiyaç olduğu görülmektedir. Bitkilerin farklı tarım uygulamaları altında en yaygın sorununun azot (N) kullanım şekli olduğu görülmektedir. Bitkinin N kullanım etkinliğinde, uygulanan gübrenin N dozu ve formunun önemli olduğu düşünülmektedir. Bu amaçla, sera koşullarında artan dozlarda (0 (kontrol), 100, 200, 400 ve 800 mg N kg-1) ve farklı formlarda (mineral, organik) N uygulamalarının buğday bitkisinin büyüme, yeşil aksamda klorofilin bir ifadesi olan SPAD değeri, yeşil aksam kuru madde verimi ve yeşil aksam N konsantrasyonu üzerine etkisi belirlenmiştir. Denemeden elde edilen bulgulara göre, N noksanlığından kaynaklı verim kayıplarının olduğu buna karşılık N uygulamasının söz konusu verim kayıplarının önüne geçtiği saptanmıştır. Azot uygulamasından kaynaklı verim artış oranları üzerine uygulanan N formunun da önemli olabildiği belirlenmiştir. Özellikle mineral gübre uygulamasında verim artış oranlarının %58 ile %87 arasında değiştiği buna karşılık organik kaynaklı gübre uygulamalarının verim değerlerinde kısmen düşüşe neden olduğu görülmüştür. Farklı formlardaki N uygulamaları, bitkinin yeşil aksam kuru madde veriminin aksine yeşil aksam N konsantrasyonunu arttırmıştır. Bu artışlarda, N uygulama dozunun önemli olduğu buna karşılık uygulanan gübre formunun önemli bir farklılık yaratmadığı belirlenmiştir. Sonuçlar genel olarak değerlendirildiğinde en etkin N uygulama dozunun 200 mg kg-1 olduğu, bunun dışında N formları içinde bitkinin büyümesinde ve N kullanım etkinliğinde en etkin formun organik kaynaklı gübre olduğu görülmüştür.
Show more [+] Less [-]Habilidad combinatoria general y específica de líneas endogámicas de maíz tolerantes a bajo fósforo Full text
2008
Salazar Villarreal, Fredy Antonio | Narro León, Luis Alberto | Vallejo Cabrera, Franco Alirio
Los cruzamientos dialelos de 12 padres contrastantes en la toma y uso de fósforo se evaluaron en dos niveles de fósforo (4 y 15 ppm) usando un diseño experimental de alpha lattice con tres repeticiones. Se usó el diseño genético propuesto por Hallauer y Miranda. En bajo y alto fósforo se encontraron diferencias altamente significativas entre los genotipos, i.e. cruzamientos (C), padres (P) y PvsC. En alto fósforo, PvsC explicaron 58% de la suma de cuadrados de los genotipos y los cruzamientos 66% en bajo fósforo. En bajo fósforo se encontraron diferencias altamente significativas para el contraste de tolerantes (T) vs susceptibles (S). Los cruzamientos de padres TxT, SxS y TxS fueron estadísticamente diferentes, lo que sugirió que el carácter es poligénico. HCG y HCE fueron altamente significativas en los dos ambientes y HCE fue tres veces más grande, lo que sugirió que en la tolerancia a bajo fósforo son más importantes los efectos genéticos no aditivos. | Twelve corn inbreeds contrasting in P use efficiency available at CIMMYT collection of CIAT, Colombia were studied. The inbreeds and their diallel crosses were evaluated under 2 P levels (4 and 15 ppm) using the alpha lattice design. The genetic design was performed according to Hallauer and Miranda (1986). Highly significant differences were found among parents (P), crosses (C) and P vs C in both environments (low and high P levels). At low P, crosses sum of squares (SS) accounted for 66% of genotype SS while at high P, P vs C accounted for 58% of genotype SS, meaning that heterosis was more important at high P. At low P, significant differences were found for tolerant (T) parents vs susceptible ones (S). Crosses among TxT, SxS and TxS parents were different, suggesting a polygenic inheritance for this trait. General (GCA) and specific combining ability (SCA) were highly significant at low and high P but SCA was 3 fold the GCA, meaning that no additive gene effects were more important for P use efficiency.
Show more [+] Less [-]Antiviral Effects of Microalgae Full text
2021
Aybike Türkmen | İhsan Akyurt
Antiviral Effects of Microalgae Full text
2021
Aybike Türkmen | İhsan Akyurt
Microalgae, also called phytoplankton by biologists, are very small plant-like organisms with a diameter of 1-50 micrometers without roots, stem and leaves. Microalgae, which have hundreds of thousands of species in both fresh waters and seas, form the lowest link of the food chain in aquatic ecosystems. Most species contain chlorophyll, use sunlight as an energy source, and convert carbon dioxide into biomass (biomass). Because of their role in the photosynthesis process, microalgae produce most of the oxygen in the atmosphere. It has a very wide biodiversity and is reported to contain more than 200 thousand species. As a result of genetic analysis, a continuous increase in microalgae species is observed. More than 15 thousand new chemical compounds have been discovered from algae in recent years. It has been observed that most of the bio compounds obtained from microalgae have antiviral effects. However, although extensive research has been done on the antibacterial, antioxidant and antifungal effects of these bioactive compounds, there is limited research on their antiviral effects. In these limited number of studies on the antiviral effects of microagines, it has been reported that some biocompounds isolated from algae may be effective against viruses that are the cause of diseases such as “HIV, SARS and AIDS”. However, the number of researches on viruses that cause today's biggest pandemic, such as coronavirus, of different biocompounds isolated from microalgae, is very small. To date, no vaccine that can be effective against the COVID-19 virus or a drug that can inhibit the reproduction of the virus has not been found. It is thought that micro or macro algae may be one of the most promising natural resources in solving this global health problem. Because Spirulina, which is a microalgae, has antiviral, anticancer, antidiabetic, antibiotic, antioxidant, prebiotic, cardiovascular system protective and antiallergic effects and these positive effects are caused by bioactive compounds found in high content (Rosales-Mendoza et al., 2020a). In this review, especially the antiviral effects of microalgae were tried to be summarized and it was tried to be emphasized that algae could be promising natural resources in the development of new antiviral drugs by our country's scientists.
Show more [+] Less [-]Efecto de variedades de algodón genéticamente modificadas sobre larvas de Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) Full text
2014
Valencia Cataño, Sandra Jimena(Centro Internacional de Agricultura Tropical (CIAT)) | Rodríguez Chalarca, Jairo(Centro Internacional de Agricultura Tropical (CIAT)) | Mesa Cobo, Nora Cristina(Universidad Nacional de Colombia, sede Palmira Facultad de Ciencias Agropecuarias)
Spodoptera frugiperda es una plaga polífaga de importancia económica en países tropicales y subtropicales. En Colombia ataca el algodonero (Gossypium hirsutum L.), cultivo que ha tomado importancia gracias a la adopción de variedades genéticamente modificadas (GM). En el estudio se determinaron los efectos subletales de algunas de estas variedades sobre larvas de este insecto. Para el efecto, en condiciones de laboratorio (27°C, 65 ± 10% HR y 12 h fotoperiodo) se evaluaron las variedades NuOPAL RR (proteína Cry1Ac), DP141 B2RF (proteínas Cry1Ac+Cry2Ab) y DeltaOPAL RR (no Bt). Los parámetros evaluados fueron: (a) peso de larvas, (b)peso de heces, (c) peso del alimento ofrecido y (d) peso del alimento no consumido. Como índices de consumo y digestibilidad se calcularon la tasa relativa de consumo (TRCo), la tasa relativa de crecimiento (TRCr), la eficiencia de conversión del alimento ingerido (ECI) y la digestibilidad aproximada (DA). Los índices mostraron actividad antialimentaria de la variedad DP141 B2RF (Cry1Ac+Cry2Ab) que afecta de forma negativa la tasa de crecimiento y la conversión del alimento por parte de las larvas. El peso de las larvas alimentadas en DP141 B2RF (Cry1Ac+Cry2Ab) fue 58.6% menor que en la variedad no Bt. Los resultados muestran un efecto adverso de la variedad DP141 B2RF (Cry1Ac+Cry2Ab) en el desarrollo larval de S. frugiperda. Se confirman los efectos antibióticos de las variedades GM evaluadas que inciden en un menor desarrollo y en la supervivencia de las larvas. | Spodoptera frugiperda, is a polyphagous pest with economic importance in tropical and subtropical countries. In Colombia, S. frugiperda is a secondary pest in cotton. This cultivar has gained importance due to the adoption of genetically modified crops (GM). The objective of this study was to determine the sub-lethal effects of GM cotton varieties on S. frugiperda larvae. In order to do so, NuOPAL RR (Cry1Ac), DP141 B2RF (Cry1Ac+Cry2Ab) and DeltaOPAL RR (No-Bt) varieties were tested under laboratory controlled conditions (27°C, 65 ±10% RH and 12 h photoperiod). The parameters to be evaluated were: (a) weight of larvae, (b) weight of feces, (c) weight of provided food and, (d) weight of non-consumed food. Digestibility and consumption indexes were calculated: Relative Consumption Rate (RCR), Relative Growth Rate (RGR), Efficiency of the Conversion of Ingested Food (ECI) and the Approximate Digestibility (AD). The nutritional indexes show antifeedant activity of DP141 B2RF, (Cry1Ac+Cry2Ab), affecting in a negative way the growth rate and the conversion of larvae food. The weight gained by larvae fed with DP141 B2RF (Cry1Ac+Cry2Ab) was 58.6% less than the control. These results suggest an unfavorable effect of DP141 B2RF (Cry1Ac+Cry2Ab) in the larval development of S. frugiperda. The antibiotic effects were confirmed observing minor development and a negative effect in the survival of larvae fed on GM cotton.
Show more [+] Less [-]Efecto de variedades de algodón genéticamente modificadas sobre larvas de Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) Full text
2014
Valencia Cataño, Sandra Jimena | Rodríguez Chalarca, Jairo | Mesa Cobo, Nora Cristina
Spodoptera frugiperda es una plaga polífaga de importancia económica en países tropicales y subtropicales. En Colombia ataca el algodonero (Gossypium hirsutum L.), cultivo que ha tomado importancia gracias a la adopción de variedades genéticamente modificados (GM). En el estudio se determinaron los efectos subletales de algunas de estas variedades sobre larvas de este insec-to. Para el efecto, en condiciones de laboratorio (27°C, 65 ± 10% HR y 12 h fotoperiodo) se eva-luaron las variedades NuOPAL RR (proteína Cry1Ac), DP141 B2RF (proteínas Cry1Ac+Cry2Ab) y DeltaOPAL RR (no Bt). Los parámetros evaluados fueron: (a) peso de larvas, (b)peso de heces, (c) peso del alimento ofrecido y (d) peso del alimento no consumido. Como índices de consumo y digestibilidad se calcularon la tasa relativa de consumo (TRCo), la tasa relativa de crecimiento (TRCr), la eficiencia de conversión del alimento ingerido (ECI) y la digestibilidad aproximada (DA). Los índices mostraron actividad antialimentaria de la variedad DP141 B2RF (Cry1Ac+Cry2Ab) que afecta de forma negativa la tasa de crecimiento y la conversión del alimento por parte de las larvas. El peso de las larvas alimentadas en DP141 B2RF (Cry1Ac+Cry2Ab) fue 58.6% menor que en la variedad no Bt. Los resultados muestran un efecto adverso de la variedad DP141 B2RF (Cry1Ac+Cry2Ab) en el desarrollo larval de S. frugiperda. Se confirman los efectos antibió-ticos del las variedades GM evaluadas que inciden en un menor desarrollo y en la supervivencia de las larvas
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