Nitrik Oksit Uygulamalarının Bitkilerde Abiyotik Stres Şartlarına Toleransı Arttırmadaki Etkileri

Yıl 2018, , 254 - 265, 29.06.2018

Melek Ekinci , Selda Örs , Metin Turan , Ertan Yıldırım

https://doi.org/10.29133/yyutbd.427960

Öz

Günümüzde bitkisel üretimini sınırlandıran çevresel stres faktörleri
nedeniyle, yetiştiricilikte bitkinin normal ürün potansiyeline ulaşmasını
sağlayacak uygun alanların bulunması oldukça zorlaşmıştır. Tarımsal üretimin
azalmasında çok büyük oranda abiyotik stres, daha düşük oranlarda ise diğer
stres faktörleri etkilidir. Abiyotik stres faktörleri olarak, kuraklık, tuzluluk,
yüksek ve düşük sıcaklık, sel, radyasyon, ağır metaller, oksidatif stres,
rüzgâr, besin maddesi eksikliği gibi faktörler sayılabilir ve bu stres
kaynakları bitki gelişimini, kaliteyi ve verimliliği olumsuz yönde
etkilemektedir. Gaz halindeki farklı bileşikler arasında, nitrik oksitin (NO)
bitkilere dışarıdan uygulanması son yıllarda daha fazla önem kazanmıştır. NO
tohum çimlenmesi ve fide büyümesinin iyileştirilmesi gibi bitkilerde
düzenleyici rollerinin yanı sıra, metal toksisitesi, sıcaklık, kuraklık ve
tuzluluk gibi farklı abiyotik streslere karşı da koruyucu bir rol oynamaktadır.
Bu makalede bitkilerin kuraklık, tuzluluk, yüksek ve düşük sıcaklık ile ağır
metaller gibi abiyotik stres koşullarında NO uygulamalarının etkileri
tartışılmıştır.

Anahtar Kelimeler

Nitrik oksit, Abiyotik stres, Bitki gelişimi, Tolerans

Effects of Nitric Oxide Applications on Tolerance of Plants in Abiotic Stress Conditions

Öz

Due to the major environmental stress factors
that limit crop production today, finding suitable areas where the plant can reach
the normal crop potential in cultivation has become very difficult. Abiotic stress is a significant factor in
decreasing the agricultural production as compared to the other stress factors.
Abiotic stress factors, such as drought, salinity, high temperature, low
temperature, flooding, radiation, pollutants, oxidative stress, wind and lack
of nutrients in the soil, can negatively affect the growth, development and
productivity of plants. Among the compounds with different gas contents,
external application of nitric oxide (NO) to plants has gained more importance
in recent years. NO plays a protective role against different abiotic stresses
such as metal toxicity, temperature, drought and salinity, as well as regulatory
roles in improvement of germination and seedling growth. This paper discusses
the effects of NO applications on abiotic stress conditions such as drought,
salinity, high and low temperature and heavy metals on plants.

Anahtar Kelimeler

Abiotic stress, plant growth, nitric oxide, tolerance

Kaynakça

• KAYNAKLAR
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