Bitkilerde Kurşun Toksisitesi ve Kurşun Toleransı

Year 2020, Volume: 3 Issue: 4, 329 - 339, 01.10.2020

Ali Doğru

Abstract

Doğada kalıcı ve toksik bir kirletici olarak kurşunun canlı organizmalar için bilinen biyolojik bir fonksiyonu olmadığı gibi yüksek kurşun konsantrasyonları bitkiler için zararlıdır. Bitkiler tarafından kök yoluyla alınan kurşunun büyük kısmı köklerde tutulurken çok az bir kısmı bitkinin toprak üstü organlarına taşınır. Böylece kurşunun besin zincirine katılması kısıtlanmış olur. Kurşun bitkilerde aktif oksijen türlerinin birikim hızını artırarak oksidatif strese neden olmaktadır. Sonuçta tohum çimlenmesi, fide büyümesi, proteinler, fotosentez, solunum, mineral madde beslenmesi ve su ilişkileri üzerinde olumsuz etkilere neden olur. Bitkiler kurşunun dokularındaki dağılımını engelleyerek, özellikle vakuollerde depo ederek ve antioksidant sistemin çeşitli bileşenleri ile kurşun toksisitesine karşı tolerans göstermeye çalışır. Bu çalışmada kurşun toksisitesinin bitkilerde neden olduğu metabolik bozukluklar ve tolerans mekanizmaları tartışılmıştır.

Keywords

Antioxidant, Kurşun, Pb, Toksisite, Tolerans

Supporting Institution

Sakarya Üniversitesi Bilimsel Araştırma Projeleri Koordinasyon Birimi

Project Number

2011-50-01-026

Lead Toxicity and Lead Tolerance in Plants

Abstract

As a persistant and toxic pollutant in nature, lead does not have any known biological importance for living things and higher lead concentrations are harmful for plants. Lead enters plants mainly through the roots. A considerable amount of lead is sequestered in the roots while small amount is translocated to the leaves. Thus contamination of the food chain by lead is restricted. Lead causes oxidative stress in plants by accelerating the formation rate of active oxygen species. As a result, it leads to some noxious effects on plants such as germination, seedling growth, proteins, photosynthesis, respiration, mineral nutrition and water relations. Plants try to acquire tolerance by preventing translocation of lead, sequestering it in vacuoles and antioxidant system. In this study, metabolic anomalies caused by lead toxicity and tolerance mechanisms in plants are discussed.

Keywords

Antioksidant, Lead, Pb, Toxicity, Tolerance

Project Number

2011-50-01-026

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