Response of rice genotypes to salinity under hydroponic conditions

Abstract

The experiment was aimed at assessing the response of 30 rice genotypes to different levels of salinity using NaCl concentration as salt stress at early seedling stage under hydroponic conditions. The experiment was replicated three times in a Completely Randomized Design for two years. The 30 rice genotypes evaluated for root length, fresh root weight, dry root weight, shoot length, fresh shoot weight, dry shoot weight, seedling biomass and shoot/root length ratio. The four salinity treatments/levels (0, 4, 6 and 12 dS/m) significantly affected the response of the 30 rice genotypes for all the traits evaluated. The interaction between salinity treatments and the genotypes was significant for all traits except fresh root weight, shoot length and dry shoot weight. The genotypic response revealed reduction in performance as the salinity level increases for all the traits, 10 genotypes were tolerant at all salinity levels. The most affected seedling trait due to salinity stress was seedling biomass at 6 dS/m (54.84%) and was expressed by genotype IR29 (susceptible check), followed by ROK 24 at 12 dS/m (54.43%). Eight rice genotypes; CK73, ITA212 (FARO 35), ITA222 (FARO 36), OG0315, OG250315, OW0315, TOG 5681 and Pokkali (Tolerant Check) were classified highly tolerant by both Stress Tolerance Index (SST) and Stress Susceptible Index (SSI), while FARO 61 (NERICA L -34) and IR72 were moderately tolerant. These rice genotypes have good potentials for further salt tolerance breeding.

Screening of Rice Accessions for Tolerance to Drought and Salt Stress Using Morphological and Physiological Parameters

“…When the means of the Stress Response Indices for all the parameters were taken into consideration, RAM 137 and FARO 44 were clearly tolerant to salt stress, FARO 61, FARO 63, NERICA 8, NERICA 4, and FARO 60 were moderately tolerant while FARO 64, FARO 52, NERICA 2 and FARO 55 were sensitive (Table 3). This result is in agreement with reports by Uyoh et al [29] and Kargbo et al [49] on the status of FARO 61. Most of the varieties used in these studies were different.…”

Growth, Physiological, and Photosynthetic Responses of Xanthoceras sorbifolium Bunge Seedlings Under Various Degrees of Salinity

“…Numerous studies have reported on the effect of salt stress on leaves and roots, and their results revealed that salt stress exerted distinct effects on growth, photosynthesis, membrane permeability, osmotic adjustment substance, enzyme activity, and so on (Sorkheh et al, 2012 ; Kargbo et al, 2019 ; Yang et al, 2020 ). In addition, researchers have provided important insights into salt and saline-alkali stress tolerance of yellow horn ( X. sorbifolium ) on physiological and transcriptomic levels (Wang et al, 2020 ).…”

Impact of Salinity on Germination and Seedling Growth of Four Cool-Season Turfgrass Species and Cultivars

“…Relative water content (RWC) as percentage of SFM was calculated the following formula: RWC (%) = SFM-SDM/SFM x 100 [10]. Furthermore, a tolerance index (TI) was calculated for each cultivar of species; i.e., shoot dry mass (SDM) was calculated by adopting the following formula [27]: TI = SDM in salinity stress/SDM in control x 100.…”