Background and Objective: Thailand encounters saline soil problems scattered in many areas which affect the agricultural area and causes a decrease in productivity especially growing rice, which is the main economic crop. Rice is the staple food of the Thai people. The rice that was used in this research is a native rice cultivar, which has a special feature: The Malidum cultivar with black grain and the Malidang rice grain with red color. It has high nutritional value in color grains, especially with antioxidants, which todayʼs consumers are more attentive and consuming this rice. To study the impact of salinity stress in rice (Oryza sativa L.) using two cultivars (Malidum and Malidang). Materials and Methods: Seeds germinated for 7 days. After that, the seedlings were transplanted into grown in Hoaglandʼs solution (modified) with NaCl added at concentrations of 0 (control), 50, 100 and 200 mM. Until the plants were 35 days old, the results were recorded and analyzed. The experiment consisted of four replicates in each treatment. Results: The NaCl had an effect on rice growth. The height, fresh weight, dry weight and chlorophyll A and B contents decreased when increasing the NaCl concentration significantly at the 95% confidence level and found that when plants were exposed to increased salinity concentrations, Malidum had a percentage reduction (compared to control) of height and chlorophyll B was higher than Malidang, while in Malidang there was a higher percentage reduction of fresh weight, dry weight and chlorophyll A than Malidum. In Malidang the total sugars increased to the highest concentration at 50 mM NaCl. Conclusion: A comparison of salt tolerance between two cultivars of rice found that the Malidang cultivar had a greater tolerance than the Malidum cultivar.

Background and Objective: Wolffia (Wolffia globosa (Roxb.) Hartog & Plas) is a nutritious plant that is used as food for humans and animals. In this study, the work aimed to determine the influence on the growth of W. globosa of light (non-shaded and shaded 50% of light intensity), aeration (aeration and without aeration) and Hoaglandʼs solution concentration of 1/2, 1/4 and 1/6 compared with the control (full strength Hoaglandʼs solution). Materials and Methods: Cultures of 100 g of W. globosa were grown in plastic boxes (32×40 cm) containing 3 L Hoaglandʼs solution. Supplied during a 12 hrs photoperiod the light intensity was 10,000 lux. W. globosa was culture for 30 days. The fresh weight was recorded every 5 days until day 30 when the chlorophyll A and B contents were determined. Results: It was found that on days 15 and 20 the fresh weights of W. globosa cultured in 1/2 and 1/4 Hoaglandʼs solution were the highest. Wolffia globosa cultured without shading had fresh weights higher than the 50% light intensity with statistical significance. In contrast, the 50% light intensity showed a higher total chlorophyll content than the non-shaded, with statistical significance at the 95% confidence level. Wolffia globosa without aeration had a higher fresh weight than that with aeration statistical but this did not affect the amount of chlorophyll. Conclusion: Therefore, appropriate conditions for W. globosa are a dilute nutrient solution and light at 50% light intensity without aeration.