Salinity Stress Response of Rice (Oryza sativa L. cv. Luem Pua) Calli and Seedlings

Abstract

Soil salinity limits plant growth and production. This research investigated a suitable medium for callus induction and plantlet regeneration in the Luem Pua rice cultivar. The effect of salt stress on seedling growth was determined using in vitro culture and soil conditions. An efficient protocol for callus induction has been developed by culture sterilized seeds on the Murashige and Skoog (MS, 1962) medium containing 0.5 mg/l benzyladenine (BA) with 1 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) that resulted in a 100% callus induction. Plantlet regeneration percentage of 49% was recorded on the MS medium containing 4 mg/l BA with 0.5 mg/l 1-naphthaleneacetic acid (NAA) after 4 weeks. For salt stress investigation, the calli were treated on an induction medium containing various concentrations of NaCl (0, 50, 100, 150, and 200 mM), while two-week-old rice seedlings were planted in soil and treated with the same concentration of NaCl for 4 weeks. In vitro culture revealed that callus survival percentage decreased when NaCl concentration increased, similar to soil culture. Seedling growth under salinity treatment also decreased when NaCl concentration increased, while other physiological parameters such as total chlorophyll, chlorophyll a, chlorophyll b, green intensity, and chlorophyll fluorescence under light conditions increased under salinity stress. These changes define the growth and physiological salinity tolerance characteristics of Luem Pua rice calli and seedlings. They can be utilized as a baseline for demand-driven in vitro rice propagation, providing useful information that can be combined with other agronomic features in rice development or breeding programs to improve the flexibility of abiotic stress-tolerant cultivars.

Salinity Tolerance Evaluation of Rice (Oryza sativa L.) ‘Tubtim Chumphae’ Seedling and Early Vegetative Stage

“…Roots were fully grown in the treatment without salt stress but growth decreased when NaCl concentration increased 35 . Similar results were also recorded in shoots and roots of Cuban and Thai rice landraces 36,37 . The HCA heatmap also revealed similar results, with decreasing growth parameters at higher salt stress levels (Fig.…”

Effects of NaCl on Growth, Chlorophyll and Sugar Contents in Rice (Oryza sativa L.) Malidum and Malidang Cultivars

“…The efficiency of photosynthesis in the plant is reduced. Salinity decreased the chlorophyll content [19][20][21][22] . Salt reduces the resistance of the mesophyll 23 .…”

Bitki Doku Kültüründe Tuz Stresi Uygulamaları

“…İn vitro kültür, toprak kültürüne benzer şekilde, NaCl konsantrasyonu arttığında kallus hayatta kalma yüzdesinin azaldığını ortaya koymuştur. Tuzluluk uygulaması altındaki fide büyümesi de NaCl konsantrasyonu arttığında azalırken, toplam klorofil, klorofil a, klorofil b, yeşil yoğunluk ve ışık koşullarında klorofil floresansı gibi diğer fizyolojik parametreler tuzluluk stresi altında artmıştır [31].…”