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    An overview of regulations of genetically modified organisms in Türkiye
    (Elsevier, 2022) Bakhsh, Allah; Hossain, Md Jakir; Yerlikaya, Bayram Ali; Ayten, Sefa; Özcan, Sebahattin
    Genetically modified organisms (GMOs) are living beings whose genetic material has been artificially manipulated in a laboratory by genetic modification with plant, animal, bacterial, and viral genes in order to favor the expression of desired physiological traits or the generation of desired biological products that do not exist in nature or by traditional crossbreeding methods. GMOs have become a part of everyday life with diverse beneficial aspects, although some disadvantages exist; therefore, GMOs' production remains a highly controversial topic in many parts of the world. Initially, this outstanding agricultural practice was initiated to combat global food scarcity and famine and remains as a viable option for large-scale crop production to ensure global food security. Furthermore, the patent of GMO seeds leads to the inevitable control and dominancy of private enterprises over food production. Besides these, although there is no concrete proof, the harmful effects of GMO crops on human health are the burning question around the world. In addition to these, because of improper regulation strategy, misconceptions, and low literacy regarding the GMO products, loss of genetic diversity, and nonreturnable status of GMOs to nature after being released, the issue of labeling the GMO products is a huge problem among the consumers. Hence, GMO issues are closely related to human health aspects that should be considered and cannot be ignored by the law. Many countries have come forward with legislative action to regulate this sensitive field. As Türkiye has needed to depend on importing agricultural goods for some time, it has implemented several legislative measures to control GMO related affairs. This article will detail all contemporary GMO issues for Türkiye. © 2023 Elsevier Inc. All rights reserved.
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    Bitkilerde Rizosferden Demir Alım Mekanizmaları
    (2018) Aksoy, Emre; Yerlikaya, Bayram Ali; Ayten, Sefa; Abudureyimu, Buasimuhan
    Demir, toprakta en çok bulunan elementlerden bir tanesi olmasına karşın çözünürlüğüalkali topraklarda düşüktür. Dolayısıyla bu tür topraklarda yetişen bitkiler sürekli demireksikliği stresine maruz kalırlar. Dünyadaki tarım arazilerin üçte biri bu tür topraklardanoluştuğundan dolayı tedavi edilemeyen demir eksikliği tarımsal üretimi kısıtlar.Bitkilerde gözlenen demir eksikliğinin tedavisinde farklı demir gübrelerikullanılmaktadır. Ancak, bu gübrelerin kullanımı üretim maliyetlerini artırmaktadır.Maliyetlerin azaltılabilmesi için bitkilerin toprakta bulunan demiri en etkin biçimdekullanabilmeleri gerekir. Bunun için de ilk olarak bitkilerin topraktaki demiri nasıl kökiçerisine aldıklarının incelenmesi gerekmektedir. Son otuz yılda yapılan çalışmalardafarklı bitki gruplarının 3 farklı demir alım mekanizması kullandıkları keşfedilmiştir. Buderlemenin amacı, demirin kök içerisine alımından sorumlu taşıyıcılar ile bu taşıyıcılarhakkındaki güncel gelişmelerden bahsetmektir.
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    Exploration of Climate Change Effects on Shifting Potato Seasons, Yields and Water Use Employing NASA and National Long-Term Weather Data
    (Springer, 2020) Yagiz, Ayten Kubra; Cakici, Mustafa; Aydogan, Nazlican; Omezli, Seher; Yerlikaya, Bayram Ali; Ayten, Sefa; Maqbool, Amir
    Climate change is a threat to agriculture but also presents opportunities and requires adaptation strategies. In many countries adequate meteorological data is lacking, so this is where NASA weather data are of assistance. We aimed to develop a generic and easily applicable approach to calculate the effect of climate change on potato yields and water need. We therefore used the NASA-Langley-Gaisma weather database which has data of thousands of sites worldwide. Comparing these with national data of a particular country, Turkey in this case showed that they compare well but diverge somewhat at the lower temperature range. The evapotranspiration (ETP) rate was not supplied by NASA, so we estimated this rate by multiplying the average daily radiation in MJ/m(2) by 5. There was a good correlation with actual ETP, and where there is a systematic deviation, it will not change conclusions when comparing sites and climate change scenarios. Next, it was assumed that potato crops are planted in spring when the average daily temperature is above 13 degrees C. When the average daily temperature reaches 22 degrees C and above, it is assumed that the crop is harvested as it gets too hot. For the highland sites with summer crops, this gave planting and harvest dates that reflect reality, but for the coastal sites, the time window with this method was too short. Since there is no risk of frost, farmers plant at lower temperatures, in local niches not covered by the regional met stations. The effect of climate change, higher temperatures, shifting planting dates and a CO2 induced increased growth rate on yield and water need of the crops was well explored with the LINTUL crop growth model. At unchanged rates of incident solar radiation and unchanged planting dates, an average decrease in potential yield from 94 to 83 t/ha is calculated. Extention of summer by 20 days on average causes decrease in the frost-free period, which leads to an overall increase of potential yield of the highland summer crops by 3%. The length of the growing season of the coastal spring crops is not extended; the season just moves closer to the winter with shorter day lengths and less radiation. So here yields are not affected by adverse high temperatures but are reduced by lower radiation levels. For both highland summer and coastal spring crops, an increase in the CO2 concentration of the atmosphere from the current 415 to future level of around 550 ppm is expected to increase the radiation use efficiency, so also yields by 25%.