In this study, the uptake of Na+ into the cytosol of rice (Oryza sativa L. cvs Pokkali and BRRI Dhan29) protoplasts was measured using the acetoxy methyl ester of the fluorescent sodium-binding benzofuran isopthalate, SBFI-AM, and fluorescence microscopy. By means of inhibitor analyses the mechanisms for uptake and sequestration of Na+ in the salt-sensitive indica rice cv. BRRI Dhan29 and in th...

Under NaCl-dominated salt stress, the key to plant survival is maintaining a low cytosolic Na(+) level or Na(+)/K(+) ratio. The OsHKT1, OsHKT2, and OsVHA transporter genes might play important roles in maintaining cytosolic Na(+) homeostasis in rice (Oryza sativa L. indica cvs Pokkali and BRRI Dhan29). Upon NaCl stress, the OsHKT1 transcript was significantly down-regulated in salt-tolerant cv....

Salt-affected soil is one of the most important abiotic stresses, leading to reduce rice productivity in many regions of the world. The objective of this investigation was to determine the Na, soluble sugar and starch contents and expression of some starch-related genes in two genotypes, Pokkali (salt tolerant) and IR29 (salt sensitive), grown under 200 mM NaCl. Three-week-old rice seedlings cv...

Effects of salt stress on polyamine metabolism and ethylene production were examined in two rice (Oryza sativa L.) cultivars [I Kong Pao (IKP), salt sensitive; and Pokkali, salt resistant] grown for 5 d and 12 d in nutrient solution in the presence or absence of putrescine (1 mM) and 0, 50, and 100 mM NaCl. The salt-sensitive (IKP) and salt-resistant (Pokkali) cultivars differ not only in their...

Drought and salinity are the major environmental factors that affect rice productivity. Comparative transcriptome analysis between tolerant and sensitive rice cultivars can provide insights into the regulatory mechanisms involved in these stress responses. In this study, the comparison of transcriptomes of a drought-tolerant [Nagina 22 (N22)] and a salinity-tolerant (Pokkali) rice cultivar with...

Rice seedlings cv. Khao Dawk Mali 105 (salt-sensitive), Luang Anan (moderately salt-tolerant) and Pokkali (salt-tolerant) were exposed to 0, 50, 100 and 150 mM NaCI for 9 d. Salinity stress caused reduction in leaf relative water contents in all cultivars. Shoot length of cv. Pokkali was least affected by salinity stress whereas increased root length in response to salinity stress was apparent ...

Transcript regulation in response to high salinity was investigated for salt-tolerant rice (var Pokkali) with microarrays including 1728 cDNAs from libraries of salt-stressed roots. NaCl at 150 mM reduced photosynthesis to one tenth of the prestress value within minutes. Hybridizations of RNA to microarray slides probed for changes in transcripts from 15 min to 1 week after salt shock. Beginnin...

The severity of Zn deficiency increased with increase in soil exchangeable sodium percentage (ESP) with salt sensitive variety M1-48 scoring 6 at ESP 62 as against only score 3 by salt tolerant variety Pokkali under similar soil conditions. Strikingly, zinc contents were much higher in salt tolerant variety than in salt sensitive one. Zinc application increased zinc concentration in the roots b...

An experiment was conducted to study the performance of rice genotypes for salt tolerance under in vitro condition. Seven genotypes include salt tolerant (Pokkali, CSR 10, TRY 1 and TRY2), moderately tolerant to salt (White Ponni and BPT 5204) and susceptible (IR 29) were used for this study through embryo culture technique. Callus was initiated in MS medium + 2 mgl 2,4D + 0.5 mgl Kin and diffe...

The Indica rice (Oryza sativa L.) varieties Pokkali and Nona Bokra are well-known salt tolerance donors in classical breeding. In an attempt to understand the molecular basis of their tolerance, physiological and gene expression studies were initiated. The effect of abscisic acid (ABA) on total proteins in roots from 12-d-old seedlings of Pokkali, Nona Bokra, and the salt-sensitive cultivar Tai...