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The influence of increasing levels (0.0%, 0.05%, 0.1%, 0.2%, 0.4%, 0.6%, 0.8%, 1.2%, 1.6%, and 2.0%) of NaCl on the germination of Kentucky bluegrass (Poa pratensis), annual ryegrass (Lolium multiflorum), perennial ryegrass (Lolium perenne), creeping bentgrass (Agrostis palustris), tall fescue (Festuca arundinacea), and crested wheatgrass (Agropyron cristatum) was investigated. Kentucky bluegrass, creeping bentgrass, and crested wheatgrass had a 50% reduction in germination at 0.2%, 0.6%, and 0.6% NaCl, respectively, compared to the control and completely lost germination at 0.6%, 1.2%, and 1.6% NaCl, respectively. Seed germination in both annual ryegrass and perennial ryegrass was only 50% of the control at 1.2% NaCl and completely inhibited at 2.0% NaCl. Tall fescue, red fescue, and creeping red fescue showed a 50% reduction in germination at NaCl concentrations of 1.2%, 1.2%, and 0.8%, respectively, while showing a complete inhibition of germination at 2.0%, 2.0%, and 1.6% NaCl, respectively.
The influence of calcium (Ca++) nutrition on the growth and root tissue electrolyte leakage (EL) of carrot (Daucus carota) was investigated using a hydroponic culture system. Seedlings of `Navajo' carrot were grown for 10 weeks with roots submersed in hydroponic nutrient solutions containing 0, 0.1, 1, 2, 4, or 8 meq/L Ca++. The nutrient solution was replenished weekly with its pH maintained at 5.8 for the entire experimental period. The tap root lengths increased as solution Ca++ concentration increased. The diameter and fresh and dry weights of the tap roots increased as Ca++ concentration increased up to 4 meq/L, and then decreased at 8 meq/L Ca++. The root and petiole concentrations of sugar, potassium, and nitrate were unaffected by changes in nutrient solution Ca++ levels. The tissue EL, when tested for the stored roots, decreased as solution Ca++ concentration increased (r = 0.602). Results of this experiment suggest that calcium nutrition is essential for maintaining cell wall integrity in hydroponically grown carrot roots.
The influence of potassium (K) nutrition on the growth and sugar contents of carrot (Daucus carota L.) cv. Navajo was investigated in a greenhouse study. Seeds were germinated in 15-cm plastic pots (volume1.5 L) containing a peatlite mix (2 parts peat:1 part vermiculite:1 part perlite, v/v). Starting at 6 true-leaf stage (5 weeks from germination), plants were watered with nutrient solutions containing 0, 1, 2, 4, or 8 meq K/L for 10 weeks. While plants receiving no potassium had the lowest biomass yield, there was little or no difference in shoot or root biomass yields between different K concentrations. Root glucose and sucrose contents were the highest when plants grown with 8 meq K/L and 4 meq K/L, respectively, from the nutrient solution. The influence of nutrient solution K concentration on tissue content of K and other macronutrient elements was also determined.
Fatty acid is known as a physiologically active compound, and its composition in rice may affect human health in countries where rice is the major diet. The fatty acid composition in brown rice of 120 Korean native cultivars was determined by one-step extraction/methylation method and GC. The average composition of 9 detectable fatty acids in tested rice cultivars were as followings: myristic acid; 0.6%, palmitic acid; 21.2%, stearic acid; 1.8%, oleic acid; 36.5%, linoleic acid; 36.3%, linolenic acid; 1.7%, arachidic acid; 0.5%, behenic acid; 0.4%, and lignoceric acid; 0.9%. Major fatty acids were palmitic, oleic and linoleic acid, which composed around 94%. The rice cultivar with the highest linolenic acid was cv. Jonajo (2.1%), and cvs. Pochoenjangmebye and Sandudo showed the highest composition of palmitic (23.4%) and oleic acid (44.8%), respectively. Cultivar Pochuenjangmebye exhitibed the highest composition of saturated fatty acid (28.1%), while cvs. Sandudo and Modo showed the highest mono-unsaturated (44.8%) and poly-unsaturated (42.4%) fatty acid composition, respectively. The oleic acid showed negative correlation with palmitic and linoleic acid, while positive correlation between behenic and lignoceric acids was observed.