to C change ( Supplemental Fig. 1 ) that corresponds to change from a proline (Pro) to serine (Ser) amino acid in the 367th codon ( Supplemental Fig. 2 ). Next, the amino acid sequence of CAO in hy and WT were aligned and compared with those of
the control ( Fig. 5B ). Fig. 5. Effects of drought stress on the contents of ( A ) soluble sugar (SS) and ( B ) proline (PRO) of five Actinidia species: Actinidia macrosperma (Acma), Actinidia longicarpa (Aclo), Actinidia deliciosa ‘Hayward
The inheritance and linkage relationships among isocitrate dehydrogenase, phosphogluconate dehydrogenase, and peptidase with phenyl-alanyl-proline were determined. Progeny segregations fit a model for a dimeric enzyme encoded by one disomic locus with two alleles. Linkage associations among the three loci were not detectable with recombination fractions ranging between 0.353 to 0.481 among these loci.
Two cultivars of sweetpotato [Ipomoea batatas (L.) Lam.], Commensal and Salyboro, were subjected to salt stress using axillary bud cultures. The salt levels ranged from 0–150 mM. After 10 weeks of growth, plantlet shoot height, dry weight, number of nodes, levels of proline, soluble carbohydrate, and protein; and metal ions sodium, potassium, magnesium, and calcium, were measured. In both cultivars, proline accumulation was higher in the shoot. There was a positive correlation between the increase in soluble carbohydrates and proteins in `Commnesal', but not in `Salyboro'. More sodium accumulated in the shoots of `Salyboro' compared to `Commensal'. The accumulation of sodium reduced the calcium and potassium, but not magnesium levels. Increase in sodium levels correlated with the increase in soluble carbohydrate levels is `Salyboro', but not in `Commensal'. A similar trend was evident with praline and sodium accumulation. Based on these and previous results, the cultivar `Salyboro' appears to be more susceptible to salt stress.
Cucumber plants )Cucumis sativa cv. Beta-al-pha) were grown in a glasshouse in pots of sand with 3 NaCl levels in the nutrient solution (0.40 and 60 mM) and placed in four large water baths controlled at different temperatures (13, 18,23, and 28°C). The increase of NaCl levels decreased the vegetative growth, seed yield, and seed quality, while the increase of root zone temperature up to 23C° increased the vegetative growth, seed yield and quality. Whereas, 28°C showed lower effect than 23°C. Ethylene production and the content of proline and free amino acids were increased with increasing NaCl levels. The increase of root zone temperature till 23°C decreased ethylene production, proline, and free amino acids contents. Zero NaCl (as control) obtained with 23°C root zone temperature appeared to be the best for the over-all growth, seed yield and seed quality of cucumber plants.
Six woody plant species, (Atriplex lentiformis, Acacia ampliceps, Conocarpus erectus, Conocarpus erectus var. sericeus, Laguncularia racemosa, and Thespesia populnea) different in age, were grown in the field and irrigated with saline water (25 ppt). The physiological performance of these species was measured. Some macro- and micro-elements, carbohydrates, protein, proline, and photosynthetic pigments were estimated in the plants. The obtained results indicated in most cases, that age of plants has no effect on nutrients, protein, or carbohydrate concentrations. For each plant species, there were some differences in the chemical composition of the leaves and stems. No significant differences were detected in Mg and Mn concentrations in leaves and stems of all studied species. Photosynthetic pigments and proline concentrations were different depending on the plant species and age. The air and leaf temperature differentials, leaf conductance, and transpiration rate were also discussed. The overall growth and physiological performance of these plants was good.
Fifteen amino acids, 5 organic acids, and 3 sugars were identified and measured quantitatively during and after the rest period of ‘Elberta’ peach and ‘Chinese’ apricot flower buds. Total amino acids increased just prior to the completion of rest in peach buds. Proline and alanine were the predominant amino acids in peach buds. Glutamic acid and proline were predominant during rest. Aspartic acid, serine, and phenylalanine increased considerably after rest was completed. Total organic acids increased slightly in peach buds after rest, while malic and citric acids showed considerable increases. In apricot buds, total organic acids increased 8-fold after the rest period was completed in mid-winter. Much of the increase which occurred, mainly in the last sampling before bloom, was attributed to fumaric, citric, pyruvic, succinic, and malic acids. After completion of rest, the sugars increased from 3- to 9-fold in peach and more than 2-fold in apricot buds.
‘Thompson Seedless’ fruits from vines that received gibberellin or auxin treatment were separated into different maturity classes and stored at 0° for 98 days. Samples were withdrawn at about monthly intervals and soluble solids, total acidity, malic acid, arginine and proline were measured. Fruits with differing soluble solids concn had the same soluble solids content per berry. After 30 days of storage, the soluble solids concn and total acidity of non-GA3 treated fruits began to increase, probably as a result of water loss. Malic acid concn and content increased for 30 days in storage, remained stable for the next 28 days, and then decreased during the remainder of the storage period. The amino acids, arginine and proline, remained relatively constant during the 1st 58 days of storage and then increased greatly both in concn and content.
The effects of Fe-deficiency and Mn-deficiency in macadamia leaves on the accumulation of free amino acids and total amino acids (free plus protein amino acids) were studied in water vs. sand culture. Leaves showing severe Fe-deficiency symptoms contained substantially higher concentrations of free histidine, aspartic acid, threonine, serine, glutamic acid, proline, alanine, valine, and tyrosine than analogous control leaves. The sum of the individual free amino acids were 177% higher in the Fe-deficient leaves than in the control leaves.
Mn-deficient leaves, containing .0003% Mn, had significantly higher concentrations of free aspartic acid, threonine, glutamic acid, proline, alanine, valine, isoleucine, leucine, tryosine, and phenylalanine than analogous control leaves. The sum of the free amino acids in Mn-deficient leaves was 85% higher than in the analogous leaves from the control plants.
In chlorotic Fe-deficient leaves the concentrations of total lysine, histidine, ammonia, arginine, aspartic acid, methionine, and leucine were significantly higher than in control leaves.
Mn-deficient leaves contained significantly higher amounts of total lysine, histidine, ammonia, aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, valine, methionine, isoleucine, leucine and phenylalanine than control leaves.
The concentrations of free lysine, histidine, aspartic acid, glutamic acid, proline, alanine, and valine were higher in the leaves of plants grown in sand culture. The total ammonia, threonine, methionine, leucine, tyrosine, and phenylalanine were lower in the leaves of plants grown in water culture. Total arginine was higher in leaves from the sand culture.
There were several significant interactions between treatments and culture media on the accumulation of free and total amino acids in the Fe- or Mn-deficient leaves.
Drought and heat stress have been extensively studied in plants, but little is known about how the combination of drought and heat impact their physiology and metabolism. The metabolite profile of Arabidopsis subjected to heat, drought, and the combination of heat and drought were analyzed by gas-chromatography-mass spectrometry (GC-MS). Fatty acid retention time standards and the internal standard (IS) ribitol (adonitol) were added to each leaf sample and the polar phase was extracted, methoximated, and derivatized (trimethylsilylated) prior to analysis by GC-MS (Trace DSQ with Combi-PAL autosampler). Compounds were identified based upon retention time (relative to fatty acid standards) and comparison with reference spectra in our custom mass spectral library. Semi-quantitation of compound peak area was done relative to the internal standard. Plants subjected to both heat and drought stress accumulated sucrose and other sugars/sugar alchohols such as maltose, gulose, mannitol. The amino acid proline (Pro) was found in drought-stressed plants, but not found in drought- and heat-stressed plants. Proline has been reported to function as an osmoprotectant in cold-, salt-, and drought-stressed plants, but could be toxic to drought- and heat-stressed plants. We found that growth of heat-stressed Arabidopsis seedlings is inhibited by Pro, but not in drought- and heat-stressed seedlings. These results also indicate that sucrose replaces proline as the major osmoprotectant in heat- and drought-stressed plants. Plants subjected to combined heat and drought also exhibited enhanced respiration, suppressed photosynthesis, and distinct transcriptome expression.