Categorization of Biostimulants: Current Situation in Turkey

Öz

Biostimulants are the substances that are applied to plants as root, foliar and seed applications, which are enhancing plants’ growth, nutritional status, stress resistance, quality and yield. Biostimulants may contain organic, inorganic compounds and microorganisms together or as individual. Some of the ingredients of biostimulants maintain soil structure. Biostimulants are permitted to use in agriculture in Turkey since 2002, also their global market is estimated 2.91 USD by 2021, at a compound annual growth rate of 10.4% from 2016 to 2021. Most of the industries of mentioned products are located in USA and Europe. In general; biostimulants do not directly affect pests, so they are not classified as pesticides. In Turkey; these products are added to Official Newspaper’s (17th of February 1999, Issue No: 23614) “Pesticide Like Materials” definition, following the signification of “insect traps” as “plant activators” in 2002. Biostimulants are not classified as fertilizers regardless of they comprise nutrients or not. Their classification is still uncertain although some researchers specified the important categories. These categories are; humic and fulvic acids, amino acids and other N containing compounds, seaweed and plant extracts, chitin and chitosan biopolymers, inorganic compounds, beneficial fungi and beneficial bacteria. This review examines the biostimulants under the mentioned categories and their effects on plants’ physiology, nutrient uptake and stress tolerance.

Anahtar Kelimeler

• Amino acid,Plant Activator,Biostimulant,Fulvic Acids,Humic Acids.

Biyostimulantların Sınıflandırılması ve Türkiye’deki Durumu

Öz

Biyostimülantlar, bitki gelişimini, bitkilerin beslenmesini, ürün kalitesini ve verimini olumlu yönde etkilemek; bitkilerin strese dayanıklılığını arttırmak amacıyla; bitkilere yapraktan, topraktan veya tohuma uygulanan, içeriğinde organik veya inorganik bileşikler, mikroorganizmalar bulundurabilen, ayrıca bazılarının toprak yapısını düzenleyici etkileri de bulunan materyallerdir. Sözü edilen materyaller Türkiye’de 2002 yılından itibaren izinli olarak tüketilmekte olup, dünya çapında pazarının 2016-2021 yılları arasında, yıllık % 10.4 artış ile 2.91 milyar Amerikan Doları olması beklenmektedir. Anılan ürünlerin endüstrileri özellikle Amerika ve Avrupa kıtalarında bulunmaktadır. Biyostimülantlar; genel olarak değerlendirildiğinde zararlılar üzerine doğrudan etkili olmadıkları için pestisit sınıfına dâhil edilmemektedirler. Ülkemizde ise, 17/2/1999 tarihli ve 23614 sayılı Resmi Gazete’de yayımlanan Zirai Mücadelede Kullanılan Pestisit ve Benzeri Maddelerin Ruhsatlandırılması Hakkında Yönetmeliğin 4 üncü maddesinde yer alan “Pestisit Benzeri Maddeler” tanımına “tuzaklar” ifadesinden sonra gelmek üzere “bitki aktivatörleri” ifadesi eklenmiştir. Ancak bununla birlikte sözü edilen ürünler; içeriklerinde bitki besin elementi bulunmasına bakılmaksızın gübre sınıfına da dâhil edilmemektedirler. Biyostimülantların sınıflandırmaları tamamen kesinleşmemekle birlikte, bazı araştırıcılar tarafından önemli kategorileri belirlemiştir. Bu kategoriler; humik ve fulvik asitler, amino asitler ve diğer azotlu bileşikler, deniz yosunu ve bitki ekstraktları, kitin ve kitosan benzeri polimerler, inorganik bileşikler, yararlı mantarlar ve yararlı bakteriler şeklindedir. Bu çalışmada biyostimülantlar, belirtilen kategoriler altında incelenmiş olup, biyostimülant uygulamalarının bitki fizyolojisine, bitkilerin besin elementi alımlarına ve stres toleransına etkileri derlenmiştir

Anahtar Kelimeler

• Amino Asit,Bitki Aktivatörü,Biyostimülant,Fulvik Asit,Humik Asit.

Kaynakça

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