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At least 19 recordsLinked to original sources
PubMed2004

[Comparative study on physiological and biochemical mechanism between virus-free seedling and common seedling in Chrysanthemum morifolium from Anhui].

OBJECTIVE: To compare and explore the physiological and biochemical index of virus-free seedling and common seedling of Chrysanthemum morifolium. METHOD: Leaves of virus-free seedling and common seedling were cut down and the contents of chlorophyll a and b, MDA, and the activity of SOD, POD, CAT, and the net photosynthetic rate (Pn) were measured. RESULT AND CONCLUSION: The contents of chlorophyll and Pn of virus-free seedling were higher than those of common seedling. But were measured, the contents of MDA and the activity of SOD, POD, CAT related to the physiological resistance were lower than the latter. These could explain the phenomenon of virus-free seedling grow better than the common seedling under the same condition.

Catalase↗
PubMed2004

Comparison of quantitative trait loci controlling seedling characteristics at two seedling stages using rice recombinant inbred lines.

A better understanding of the genetics of seedling characteristics in rice could be helpful in improving rice varieties. Zhenshan 97 and Minghui 63, the parents of Shanyou 63, an elite hybrid developed during the last decade in China, vary greatly with respect to their physiological and morphological traits at the seedling growth stage. In this study, we used a population of 240 recombinant inbred lines derived from a cross between Zhenshan 97 and Minghui 63 to identify quantitative trait loci (QTL) for seedling characteristics. All plant material was grown in hydroponic culture. Data for the following characters were collected at 30 days and 40 days post-sowing: plant height, shoot dry matter weight (SDW), maximum root length, root dry weight (RDW), total dry weight, and root-shoot ratio (the ratio of SDW to RDW). Analysis using composite interval mapping detected 16 QTL for the six traits in 30-day-old seedlings. Of these 16 QTL, Minghui 63 alleles increased trait values at only two of them. The QTL in the vicinity of R3166 on chromosome 5 simultaneously influenced PH, SDW, MRL, RDW, and TDW in the same direction. Twenty QTL were detected for the same traits in the 40-day-old seedlings. However, at this stage Minghui 63 alleles increased trait values at eight QTL. The QTL linked to R3166 also affected PH, SDW, MRL, RDW, and TDW. Only four QTL were common to the two stages. These results clearly indicate that different genes (QTL) control the same traits during different time intervals. Zhenshan 97 alleles had positive effects during the first 30 days of seedling growth, but thereafter the positive effects of Minghui 63 alleles on seedling growth gradually became more pronounced.

Biomass↗
PubMed1967

Sugar uptake and translocation in the castor bean seedling I. Characteristics of transfer in intact and excised seedlings.

Changes in the dry weights of various parts of the castor bean seedling showed that the rates of transfer of material through the cotyledons to the embryonic axis exceeded 2 mg/hour after 5 to 6 days of germination. The sugar present in the endosperm was predominantly, and in the cotyledon almost exclusively, sucrose. Anatomical features were described which contribute to the efficiency of the cotyledons as organs of absorption and transmittal of sucrose to the embryonic axis, where hexoses are much more prevalent.The ability of the cotyledons to absorb sucrose survived removal of the endosperm from the seedling. A series of experiments is described in which the cotyledons of such excised seedlings were immersed in sucrose-(14)C and measurements made of uptake and of translocation to various parts of the seedling. Increasing rates of absorption were observed as the sucrose concentration was raised to 0.5 m and these rates were maintained for several hours. Removal of the embryonic axis (hypocotyl plus roots) drastically altered both the response to sucrose concentration and the time course of absorption by the cotyledons.More than 80% of the sugar normally entering the cotyledons from the endosperm is transmitted to the embryonic axis and this extensive turnover was seen also in pulse/chase experiments with excised seedlings. The cotyledons of excised seedlings absorbed sucrose against high apparent concentration gradients. The absorption was stimulated by phosphate and had a pH optimum at about pH 6.4. It was inhibited by arsenate, azide and 2,4-dinitrophenol.

Journal Article↗
PubMed1986

Root growth potential, seedling morphology and bud dormancy correlate with survival of loblolly pine seedlings planted in December in Alabama.

First-year survival of December-planted loblolly pine seedlings sampled from 20 nurseries ranged from 36 to 86%. Various characteristics of the seedlings including root growth potential (RGP), shoot/root ratio, root weight and stem length were correlated with survival. A regression model using the number of new roots >/= 0.5 cm and the shoot/root ratio accounted for 80% of the variation in first-year survival. Alone, the number of new roots >/= 0.5 cm accounted for 76% of the variation in survival. Foliar nutrients were not correlated with survival. Seedlings with a high proportion of quiescent buds at planting had a higher RGP and better survival than seedlings with dormant (endodormant) buds. The data suggest that seedlings with dormant buds should not be planted on sites where rapid new root growth is needed for survival.

Journal Article↗
PubMedDate not supplied

Spatial structure and richness of ectomycorrhizal fungi colonizing bioassay seedlings from resistant propagules in a Sierra Nevada forest: comparisons using two hosts that exhibit different seedling establishment patterns.

In this study we analyzed the spatial structure of ectomycorrhizal fungi present in the soils as resistant propagules (e.g. spores or sclerotia) in a mixed-conifer forest in the Sierra Nevada, California. Soils were collected under old-growth Abies spp. stands across approximately 1 km and bioassayed with seedlings of hosts that establish best in stronger light (Pinus jeffreyi) or that are shade-tolerant (Abies concolor). Ectomycorrhizal fungi colonizing the roots were characterized with molecular techniques (ITSRFLP and DNA sequence analysis). Wilcoxina, five Rhizopogon species and Cenococcum were the most frequent of 17 detected species. No spatial structure was detected in the resistant propagule community as a whole, but P. jeffreyi seedlings had higher species richness and associated with seven Rhizopogon species that were not detected on A. concolor seedlings. We drew two conclusions from comparisons between this study and a prior study of the ectomycorrhizal community on mature trees in the same forest: (i) the resistant propagule community was considerably simpler and more homogeneous than the active resident community across the forest and (ii) Cenococcum and Wilcoxina species are abundant in both communities.

Abies↗
PubMed2002

Effects of substrates composed of biosolids on the production of Eucalyptus viminalis, Schinus terebinthifolius and Mimosa scabrella seedlings and on the nutritional status of Schinus terebinthifolius seedlings.

Six substrates made up with heated and composted anaerobic biosolid were tested for the production of Eucalyptus viminalis, Schinus terebinthifolius and Mimosa scabrella forest seedlings in a nursery in Southern Brazil. The produced seedlings were statistically evaluated in relation to height, stem diameter, height/stem diameter ratio, aerial and root dry biomass, survival, and also for nutritional status on S. terebinthifolius seedlings. As a function of their high pH, heated biosolids turned out to be viable only in low composition percentages. Composted biosolids turned out to be sufficiently suitable in percentages between 30% and 60% of the substratum--whose Mn and Zn concentrations relate the nutrient contents in theseedlings -with use viability up to 100% in substratum composition.

Anacardiaceae↗
PubMed1986

Biosynthesis of the Macrocyclic Diterpene Casbene in Castor Bean (Ricinus communis L.) Seedlings : The Purification and Properties of Farnesyl Transferase from Elicited Seedlings.

FARNESYL TRANSFERASE (FARNESYL PYROPHOSPHATE: isopentenyl pyrophosphate farnesyl transferase; geranylgeranyl pyrophosphate synthetase) was purified at least 400-fold from extracts of castor bean (Ricinus communis L.) seedlings that were elicited by exposure for 10 h to Rhizopus stolonifer spores. The purified enzyme was free of isopentenyl pyrophosphate isomerase and phosphatase activities which interfere with prenyl transferase assays. The purified enzyme showed a broad optimum for farnesyl transfer between pH 8 and 9. The molecular weight of the enzyme was estimated to be 72,000 +/- 3,000 from its behavior on a calibrated G-100 Sephadex molecular sieving column. Mg(2+) ion at 4 millimolar gave the greatest stimulation of activity; Mn(2+) ion gave a small stimulation at 0.5 millimolar, but was inhibitory at higher concentrations. Farnesyl pyrophosphate (K(m) = 0.5 micromolar) in combination with isopentenyl pyrophosphate (K(m) = 3.5 micromolar) was the most effective substrate for the production of geranylgeranyl pyrophosphate. Geranyl pyrophosphate (K(m) = 24 micromolar) could replace farnesyl pyrophosphate as the allylic pyrophosphate substrate, but dimethylallyl pyrophosphate was not utilized by the enzyme. One peak of farnesyl transferase activity (geranylgeranyl pyrophosphate synthetase) and two peaks of geranyl transferase activity (farnesyl pyrophosphate synthetases) from extracts of whole elicited seedlings were resolved by DEAE A-25 Sephadex sievorptive ion exchange chromatography. These results suggest that the pathway for geranylgeranyl pyrophosphate synthesis in elicited castor bean seedlings involves the successive actions of two enzymes-a geranyl transferase which utilizes dimethylallypyrophosphate and isopentenyl pyrophosphate as substrates and a farnesyl transferase which utilizes the farnesyl pyrophosphate produced in the first step and isopentenyl pyrophosphate as substrates.

Journal Article↗
PubMed2006

Leaf surface characteristics of apple seedlings, bean seedlings and kohlrabi plants and their impact on the retention and rainfastness of mancozeb.

A study was made of the influence of the upper leaf surface characteristics on the retention and rainfastness of the contact fungicide mancozeb with and without tank-mix adjuvants (RSO 5 and RSO 60) on apple seedlings, bean seedlings and kohlrabi plants. Large differences in roughness, in the amount and composition of surface waxes and in the retention and rainfastness of mancozeb were found among species. Strong correlations between roughness and total amount of surface waxes and mass of C29 alkane in the wax mass were also found. Fungicide retention was strongly, negatively correlated with surface roughness, total epicuticular wax, amount of C29 alkane and the total mass of alkanes. Rainfastness correlated strongly or very strongly with the amount of C28 alcohol and C33 alkane. The addition of a more hydrophobic (RSO 5) or a more hydrophilic (RSO 60) adjuvant to the spray solution influenced retention and rainfastness, and also altered the correlation coefficients. The present results support earlier observations which show that the success of adjuvants in enhancing the retention and rainfastness of agrochemicals depends on the characteristics of the leaf surface.

Adjuvants, Pharmaceutic↗
PubMed1980

Invertases in Oat Seedlings: SEPARATION, PROPERTIES, AND CHANGES IN ACTIVITIES IN SEEDLING SEGMENTS.

The soluble invertase activity in etiolated Avena seedlings was highest at the apex of the coleoptile and much lower in the primary leaf, mesocotyl, and root. The activity in all parts of the seedling consisted of two invertases (I and II) which were separated by chromatography on diethylaminoethylcellulose. Both enzymes appeared to be acid invertases, but they differed in molecular size, pH optimum, and the kinetic parameters K(m) and V(max) of their action on sucrose, raffinose, and stachyose. Invertase II had low stability at pH 3.5 and below, and exhibited high sensitivity to Hg(2+), with complete inhibition by 2 micromolar HgCl(2). Segments of coleoptiles incubated in water lost about two-thirds of the total invertase activity after 16 hours. The loss of activity was due primarily to a decrease in the level of invertase II. The loss of invertase was decreased by indoleacetic acid, 2,4-dichlorophenoxyacetic acid, and alpha-naphthaleneacetic acid but not by beta-naphthaleneacetic acid and p-chlorophenoxyisobutyric acid. Conditions that inhibited auxin-induced growth of the segments (20 millimolar CaCl(2) and 200 millimolar mannitol) also blocked the auxin effect on invertase loss.

Journal Article↗
PubMed2004

The importance of seed reserves for seedling performance: an integrated approach using morphological, physiological, and stable isotope techniques.

To investigate how seed reserves affect early seedling performance, we conducted a factorial greenhouse experiment using Lithocarpus densiflora (Tanoak). Seedlings were grown from large (5.8+/-0.7 g) and small (3.2+/-0.4 g) seeds and, following shoot emergence, seeds were either removed or left attached. Seedlings were harvested for quantification of biomass and delta13C at seven time periods following seed removal (2, 4, 8, 16, 32, 64, 128 days) and seedling photosynthesis was measured three separate time periods (2-4, 49-82, 95-128 days after seed removal). Biomass increased for all seedlings, but the increase was significantly larger for seedlings with attached seeds than with removed seeds. Seed removal just after shoot emergence significantly decreased seedling biomass, but seed removal 64 days after shoot emergence had no effect on seedling biomass. Seedling photosynthesis per unit leaf area varied by time and seed presence, but not by seed size. At the first period, seedlings with attached seeds had significantly higher photosynthetic rates than seedlings with removed seeds, at the second period there was no effect of seed removal, and at the third time period seedlings with attached seeds had significantly lower photosynthetic rates than seedlings with removed seeds. Despite temporal variation in photosynthesis per unit leaf area, seedlings with attached seeds always had significantly greater leaf area than seedlings with removed seeds, resulting in significantly higher total plant photosynthesis at all three time periods. The delta13C values of both the leaves and roots were more similar to that of the seed for seedlings with attached seeds than for seedlings with removed seeds, however, seed removal and seed size strongly affected root delta13C. This study demonstrates that seed reserves have important effects on the early growth, physiology, and delta13C of L. densiflora seedlings.

Analysis of Variance↗
PubMed2002

Importance of the ectomycorrhizal network for seedling survival and ectomycorrhiza formation in rain forests of south Cameroon.

An investigation was undertaken at two sites south Cameroon to assess the importance of living roots of adult trees as sources of inoculum for survival, ectomycorrhizal colonisation and growth of seedlings of Paraberlinia bifoliolata. One-month-old seedlings of Paraberlinia bifoliolata, isolated from or in contact with roots of adult target trees, were transplanted in concentric circles 5, 10, 15, and 30 m away from the stem bases of four adult tree species (Afzelia bipindensis, Brachystegia cynometroides, Paraberlinia bifoliolata and Tetraberlinia bifoliolata). After 4 and 8 months, survival, ectomycorrhiza formation and seedling height were observed; plant biomass was determined after 8 months. After 4 months, there was no difference in seedling survival between seedlings in contact with roots of adult trees and isolated seedlings. The number of ectomycorrhizal seedlings was higher among seedlings in contact with adult trees than among isolated seedlings. After 8 months, both seedling survival and ectomycorrhiza formation were higher in seedlings in contact with roots than in isolated seedlings. Seedling survival and ectomycorrhiza formation were highest under Brachystegia. The fraction of surviving seedlings that had formed ectomycorrhizas was lowest under Afzelia. The fraction of surviving seedlings that were ectomycorrhizal declined monotonically towards the edge of the crown projection. Biomass of seedlings in contact with adult trees was significantly higher than that of isolated seedlings. This difference was consistent for all four tree species. The height of seedlings did not vary with the treatment.

Cameroon↗
PubMed2005

[Effect of ectomycorrhizae on the growth of Picea koraiensis seedlings].

Basidioscarps of Agaricales in different Picea koraiensis forest plantations were collected during August-October, 2000. 36 isolaters of species of Agaricales were obtained by isolating and culturing to the basidioscarps. Through indoor inoculation test on seedlings of Picea koraiensis, 6 ectomycorrhizae fungi cultures were obtained from 36 isolaters. The inoculation results show that the period for ectomycorrhizae inoculation to 1-year seedlings of Picea koraiensis should be about 30 days after seedlings emerging, the suitable temperature for ectomycorrhizae forming is about 20 degrees C. 6 ectomycorrhizae strains all have growth-promoting effect to the seedlings of Picea koraiensis. The contents of chlorophyll a of the seedlings inoculated strains of Agaricus silvaticus, 031 and L15 were significantly higher than other strains and control. The contents of chlorophyll b in the seedlings inoculated strains 009, 004, Agaricus silvaticus and L15 were significantly higher than other strains and control. The weights of seedlings which inoculated strains 009, 025, 031, Agaricus silvaticus and L15 were significantly different to control, the weight of seedlings inoculated strains of Agaricus silvaticus and L15 are 19.23% and 23.08% more than control; The heights of the seedlings inoculated 6 strains all have significant difference to control, the weight of seedlings inoculated strains of Agaricus silvaticus and L15 are 17.83% and 16.37% more than control. The results of outdoor inoculation show that the seedlings inoculated Agaricus silvaticus grow best on height, 9.25% more than control after inoculated 70 days; the seedlings inoculated strain L15 grow best on collar diameter, 9.92% more than control after inoculated 70 days; the lateral root numbers of seedlings inoculated strain 009 is largest, 51.91% more than control after inoculated 70 days; the main roots of seedlings inoculated strain 009 are longest, 3.36% more than control after inoculated 70 days; the ectomycorrhizae fungi infestation percentage of seedlings inoculated strain 031 is highest, 13.90% more than control after inoculated 70 days; the photosynthesis of seedlings inoculated strain 031 is more powerful, 20.02% more than control after inoculated 70 days. To sum up, strain 009, strain 031 and strain L15 should be fine strains to seedlings of Picea koraiensis.

Biomass↗
PubMed2003

Chilling-dependent photoinhibition, nutrition and growth analysis of Eucalyptus nitens seedlings during establishment.

Effects of chilling-dependent photoinhibition on gas exchange, chlorophyll fluorescence, growth and nutrition of Eucalyptus nitens (Deane and Maiden) Maiden seedlings were assessed for 70 weeks after transplanting 9-month-old seedlings in early winter. One month before transplanting, the seedlings were assigned to fertilized or nutrient-deprived treatments. Immediately after transplanting, half the seedlings in each nutrient treatment were placed in shadecloth tree shelters. The experimental site was at an altitude of 700 m, which is considered marginal for the establishment of E. nitens plantations in Tasmania because of low mean annual minimum temperatures. Overnight frosts followed by sunny morning conditions in the first 20 weeks after transplanting (early June to early October) caused severe photoinhibition. Predawn maximal photochemical efficiency (Fv/Fm) and maximum net photosynthesis (Amax) were depressed in nutrient-deprived seedlings compared with fertilized seedlings, although shading partially alleviated this difference. Neither Fv/Fm nor Amax recovered to values observed before transplanting until > 20 weeks after transplanting. During this period, non-photochemical quenching (NPQ) was high in seedlings in all treatments, although NPQ was lower in shaded, fertilized seedlings than in seedlings in the other treatments. Total foliar nitrogen (N) concentration increased up to 42 weeks after transplanting in the nutrient-deprived seedlings in parallel with increasing relative growth rate (RGR). Fractionation of N- and phosphorus (P)-containing compounds indicated that differences in protein N accounted for the treatment differences in total seedling N. Nucleic acid P increased and inorganic P decreased during growth periods, although total seedling P remained constant. Among treated seedlings, height growth was greatest in shaded seedlings: this was probably a result of apical dominance effects because RGR was higher in unshaded seedlings than in shaded seedlings. Thus, the shade treatment alleviated chilling-dependent photoinhibition and maximized growth during winter, but limited growth during warmer periods and therefore overall growth.

Chlorophyll↗
PubMed2004

Allocation of 14C-carbon in two species of larch seedlings infected with ectomycorrhizal fungi.

The flow of labeled carbon in ectomycorrhizal and non-ectomycorrhizal seedlings of Japanese larch (Larix kaempferi Sarg.) and its F1 hybrid (Larix gmelinii Rupr. x L. kaempferi) was studied. Larch seedlings were grown in a greenhouse for 110 days with larch forest soil (FM) or Suillus grevillei (SM) inoculum, or in the absence of ectomycorrhizal fungi (NM). Shoots of colonized and NM seedlings were exposed to a pulse of 14CO2 for 1 h under natural light. Seedlings were harvested following 0, 6 and 24 h of exposure to 14CO2. At the final harvest, SM seedlings of Japanese larch and hybrid larch allocated 2.6 and 2.5% more 14C, respectively, to roots than NM seedlings. In contrast, FM seedlings of Japanese larch and hybrid larch allocated 6.5 and 18.0% more 14C, respectively, to the stem than NM seedlings. Of the total 14C detected in needle, stem and root fractions, FM and SM seedlings allocated a greater proportion than NM seedlings, perhaps because FM and SM seedlings had significantly (P < 0.05) higher photosynthetic rates than NM seedlings. As a result, FM and SM seedlings had greater dry masses than NM seedlings. Concentrations of nitrogen and phosphorus in FM and SM seedlings were significantly (P < 0.05) higher than in NM seedlings, as was stomatal conductance.

Carbon↗
PubMed1989

Temporal allocation of (14)C to extramatrical hyphae of ectomycorrhizal ponderosa pine seedlings.

Ponderosa pine seedlings were inoculated with Hebeloma crustuliniforme either in growth pouches before they were transplanted to root-mycocosms (P seedlings), or at the time of transfer to root-mycocosms (V seedlings). Uninoculated seedlings served as controls (U seedlings). The use of root-mycocosms allowed examination of portions of hyphae separate from roots and rooting substrate but still in symbiosis with the host. The results thus provided a quantitative basis for estimating hyphal mass and carbon allocation to extramatrical hyphae. The amount of (14)CO(2) fixed after a 2-h exposure was greatest for P seedlings and least for uninoculated seedlings. Four and nine days after exposure, (14)C content was greatest in uninoculated seedlings and least in inoculated seedlings. In isotope distribution and dry mass accumulation, V seedlings were more similar to U than to P seedlings. Calculated on a dry weight basis, the allocation of isotope to mycelium suggested that extramatrical hyphae of P seedlings were a stronger sink for carbon than extramatrical hyphae of V seedlings. Differences in inoculation methods resulted in differences in carbon allocation and physiology of extramatrical hyphae that could affect seedling establishment and survival. Seedlings inoculated by one method cannot serve as surrogates for mycorrhizal seedlings produced by other inoculation techniques.

Journal Article↗
PubMed1991

Photosynthesis, water relations and mortality in Abies lasiocarpa seedlings during natural establishment.

Few studies have investigated the ecophysiology of natural seedling establishment in forest trees not associated with anthropogenic disturbance. Photosynthesis and water relations measurements were made on one- through four-year-old seedlings of Abies lasiocarpa Nutt. (subalpine fir) establishing naturally in an understory environment. First (current)-year seedlings generally had only cotyledons, whereas most second-year seedlings had both cotyledons and primary leaves. Mortality was high (> 60%) in first-year seedlings with the greatest mortality (> 90%) measured at the more open, sun-exposed sites within the understory. Seedling mortality was negligible after the first year of growth at shaded microsites and after the second year of growth at sunny microsites. Photosynthetic CO(2) uptake at light saturation was considerably lower in first-year than in fourth-year seedlings (0.6 micromol m(-2) s(-1) versus 1.7 micromol m(-2) s(-1)) and occurred at lower solar irradiance (240 micromol m(-2) s(-1) versus 600 micromol m(-2) s(-1) of photosynthetically active radiation). Differences in photosynthetic capacity were due to differences in both stomatal and non-stomatal limitations to CO(2) uptake. Carbon dioxide assimilation in first- and second-year seedlings was 28 and 29%, respectively, of the mean value measured for fourth-year seedlings. Although first-year seedlings had low transpiration rates, their water use efficiency (photosynthesis/transpiration) was less than half that of fourth-year seedlings and their water potentials were lower than those of all other age classes (0.46 mol CO(2) mmol(-1) H(2)O and -3.0 MPa, respectively). The stomatal limitation to CO(2) uptake was approximately 21% in first- and second-year seedlings, and increased to 39% in fourth-year seedlings. Intercellular CO(2) concentrations were greater in first- and second-year seedlings (255 and 250 microl l(-1), respectively) than in third- and fourth-year seedlings (203 and 186 microl l(-1), respectively). Thus, abrupt increases in water status and photosynthetic capacity after the first or second year of growth appear crucial for survival to maturity. Moreover, differences in temperature and water relations according to microsite may be major factors determining seedling establishment and, thus, the distributional and successional patterns observed for adult trees of Abies lasiocarpa.

Journal Article↗
PubMed2001

Antioxidative enzymes in seedlings of Nelumbo nucifera germinated under water.

Dry seeds of anoxia-tolerant lotus (Nelumbo nucifera Gaertn=Nelumbium speciosum Willd.) have green shoots with plastids containing chlorophyll, so photosynthesis starts even in seedlings germinated under water, namely hypoxia. Here we investigated antioxidative enzyme changes in N. nucifera seedlings responding to oxygen deficiency. The activity of superoxide dismutase (SOD; EC 1.15.1.1), dehydroascorbate reductase (DHAR; EC 1.8.5.1) and glutathione reductase (GR; EC 1.6.4.2) were lower in seedlings germinated under water (submerged condition) in darkness (SD seedlings) than those found in seedlings germinated in air and darkness (AD seedlings). In contrast, ascorbate peroxidase (APX; EC 1.11.1.11) activity was higher in SD seedlings and the activity of catalase (EC 1.11.1.6) and monodehydroascorbate reductase (MDAR; EC 1.6.5.4) in SD seedlings was nearly the same as in AD seedlings. When SD seedlings were exposed to air, the activity of SOD, DHAR and GR increased, while the activity of catalase and MDAR decreased. Seven electrophoretically distinct SOD isozymes were detectable in N. nucifera. The levels of plastidic Cu,Zn-SODs and Fe-SOD in SD seedlings were comparable with those found in AD seedlings, which may reflect the maintenance of green plastids in SD seedlings as well as in AD seedlings. These results were substantially different from those previously found in rice seedlings germinated under water.

Journal Article↗