Growth responses of NaCl stressed rice (Oryza sativa L.) plants germinated from seed in aseptic nutrient cultures supplemented with proline

Abstract

Negative impact of salinity on plant germination is significant because of abundance of Na⁺ in culture medium, which causes growth inhibition. Effect of salinity (NaCl) in the presence of proline was assessed in rice (Oryza sativa L.) variety Khushbo-95 at seedling stage. Seeds were cultured on MS₀ (MS basal medium), MS₁ (MS₀ + 100 mM NaCl) and MS₂ (MS₁ + 5 mM proline) for 20 days. Seedlings and its biomass decreased in saline culture. Similarly, total protein and sugar contents also decreased, while reducing sugars and proline contents increased. These parameters were observed to be slightly adverse in cultures supplemented with proline (MS₂) and NaCl (MS₂). Among cultures, leaf demography (cell size) was affected significantly; this may be the reflection of accumulation of proline, Na⁺ and Cl^- and exclusion of K⁺ in developed rice seedlings.

Key words: Oryza sativa L., seedling biomass, epidermal cells, proline content.