Paper Details

PJB-2026-1519

Optimizing safflower growth under copper stress via application of salicylic acid, chitosan, and nanoparticle

Naila Sarwar and Musarrat Ramzan
Abstract

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Excessive copper (Cu) levels in plants cause toxicity, stunted growth, root damage, and deficiencies in essential minerals. It also generates oxidative stress, disrupts microbial activity, and alters soil structure, making it harder for roots to grow and absorb nutrients. However, using salicylic acid (SA), chitosan (Chi), and nanoparticles (NP) can be effective, environment-friendly amendments to mitigate copper stress in plants. Nanoparticles significantly enhance plant growth by improving nutrient availability, boosting photosynthesis, and increasing stress tolerance. Salicylic acid acts as a plant hormone, improving seed germination, root development, and photosynthesis. Chitosan improves seed germination, root growth, and shoot expansion by enhancing cell multiplication and nutrient uptake. That’s why the current study aims to explore the potential of salicylic acid, chitosan, and nanoparticles as an amendment on three safflower varieties (Saff-64, Saff-50, and Saff-62) cultivated under Cu stress. Treatments include control, 400Cu, 0.01SA, Chi, 400Cu+0.01SA, 400Cu+Chi, 0.01NP, 0.1NP, 400Cu+0.01NP, and 400Cu+0.01NP in three replicates following a completely randomized design (CRD). Results showed that 0.01NP caused the highest increase in shoot length (~14%), shoot fresh weight (~51%), shoot dry weight (~55%), root fresh weight (~45%), and root dry weight (~10%) of variety Saff-62 compared to the control over the other varieties. The increase in chlorophyll a (~1%), chlorophyll b (~18%), and total chlorophyll (~2%) of variety Saff-62 above the other varieties under Cu stress also validated the effect of 0.0NP. It is concluded that variety Saff-62 is a resistant variety in contrast to the other varieties, and 0.01NP is an effective amendment for alleviating Cu stress in safflowers. Under Cu stress, farmers are suggested to maximize their crop growth by using the Saff-62 variety and applying 0.01NP as an amendment.

To Cite this article: Sarwar, N. and M. Ramzan. 2026. Optimizing safflower growth under copper stress via application of salicylic acid, chitosan, and nanoparticle. Pak. J. Bot., 58(5): DOI: http://dx.doi.org/10.30848/PJB2026-5(14)  
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