Stem Length Of Seedlings Research Articles

Utjecaj magnetnih polova na svojstva sjemena krmnog graška (Pisum sativum L.) različite starosti

The study on the influence of magnetic poles on field pea seed of the 'Bera' variety of different ages was carried out under laboratory conditions in a growing chamber. Field pea seed were exposed to a neodymium magnet's positive and negative magnetic poles with a magnetic flux density of 250 mT for 24 hours. Germination of untreated as well as magnetically poled treated seed was carried out according to ISTA rules. Seed characteristics, germination energy, and germination were determined by counting. The root and stem length of the seedlings were measured, and the total length of the field pea seedlings was added up. The total mass of the seedlings was determined by weighing. On average, seed age and magnetic poles significantly (p<0.05) increased the traits: stem length, total length, and seedling weight. On average, significant differences (p<0.05) were found for untreated and magnetic poles treated seed for all the studied traits except seedling stem length. Significant interaction (p<0.05) between magnetic pole treatment and seed age was found for all the traits studied.

Allelopathy of rape on seed germination and seedling growth of three crops

Rape is an important green manure crop in China. It could increase soil fertility, but might have allelopathic effect on subsequent crops. We examined the effects of rape water-extract (at 0.025, 0.05 and 0.1 g·mL-1 concentrations) on seed germination, seedling growth, physiology and biochemistry of three crops including oat (Avena sativa), corn (Zea mays), and sunflower (Helianthus annuus). The results showed that water extract of rape did not affect seed germination rate of three crops. Oat had a trend of "low promotion and high inhibition", while sunflower had a trend of inhibition. High concentration of rape water extract inhibited root and stem length of oat seedling, corn seedling stem length and sunflower seedling root length, while low concentration treatment promoted root and stem length of corn seedling. The highest protein contents in oats and sunflower presented at the treatment of 0.05 g·mL-1, and that of corn at the treatment of 0.025 g·mL-1, which were significantly higher than that of control. The proline contents in sunflower decreased significantly in different treatments, while the proline content of corn was significantly higher than that of control at 0.05 g·mL-1. POD activity of corn was at a maximum at 0.05 g·mL-1, and that of sunflower was at 0.025 g·mL-1, which were significantly higher than control. There was no significant difference between control and other concentration treatments. The SOD activity of oat was significantly decreased at 0.025 g·mL-1. There was no significant difference in CAT activity between the three crops and the control. The MDA content in sunflower seedlings increased significantly at 0.1 g·mL-1, while that in corn seedlings was significantly lower than control. Our results indicated that the allelopathic inhibitory effect of rape water extract was the strongest on sunflower, followed by corn and oat.

The determination of physiological and DNA changes in seedlings of maize (Zea mays L.) seeds exposed to the waters of the Gediz River and copper heavy metal stress.

In this study, the effects of the heavy metal-polluted waters of the Gediz River, which flow into the Aegean Sea, and different concentrations of copper (Cu) solutions on maize (Zea mays L.) seedlings are investigated with physiological parameters and random amplified polymorphic DNA (RAPD) assay. Results displayed physiologically a significant difference in root and stem length between the control seedlings and the seedlings grown with the waters of the Gediz River. Also, the certain ascending concentrations of copper solution (80, 160, 320, 640, and 1280ppm) caused a significant decrease in root and stem length of seedlings compared to the control seedlings. As a result of the waters of the Gediz River and copper solution treatment, the changes occurred in RAPD profiles of seedlings observed as variations like increment and/or loss of bands compared with the control seedlings. And these changes were reflected as a decrease in genomic template stability (GTS, changes in RAPD profile) derived by genotoxicity. RAPD band profiles and GTS values showed consistent results with physiological parameter. In conclusion, the study revealed the environmental risk and negative effect of waters of the Gediz River on maize seedlings and the suitability of RAPD assay for the detection of environmental toxicology.

Advantages of amphicarpy of Persicaria thunbergii in the early life history

Persicaria thunbergii is an annual Polygonaceae herb and an amphicarpic plant. To understand the advantages of amphicarpy in the early life history of P. thunbergii, we compared aerial seeds (AS) and subterranean seeds (SS) and seedlings in terms of seed size, weight, germination rate, and seedling stress response under both shaded and water-logged conditions in a mesocosm experiment. The major and minor axes of the SS were 22% and 17% longer than those of the AS, respectively. The SS were 37% heavier than the AS. Additionally, the germination rate of SS was higher than that of AS during the early phase (first germination test) and under water-logged conditions (second germination test). Average stem length of seedlings from SS in the control group was 41% longer than that of seedlings from AS. SS had greater leaf number, root length, and overall dry weight than those of AS. The SS in the shaded group had 34% longer stems and 99% wider leaf area than those of AS. Moreover, stem length of SS increased more rapidly than that of AS to escape flooding conditions. We conclude that larger and buried SS may be advantageous to re-occupy the mother site after adverse conditions, whereas lighter and AS may disperse more easily because the seeds probably disperse in water.

Dependency of arabidopsis thaliana growth on DC electric field intensity

In this paper, the dependency of Arabidopsis thaliana growth on dc field intensity was studied. One group of Arabidopsis thaliana seeds was cultivated under one intensity of electric field. Four values of 2.5, 5.0, 10.0 and 15.0 kV/m were chosen for applied field intensity. Applying duration was four days. Then, seed germination rate and stem length of seedling were obtained. As a result, it is shown that dc field improves seed germination rate and seedling stem length. Also, the length of seedling stem is increased with dc field up to 10.0 kV/m with comparatively high reliability by the statistical test, while above 10.0 kV/m it seems to saturate.

Variation in Development and Response to Root-zone pH Among Seedlings of Dirca palustris (Thymelaeaceae) from Three Provenances

Horticulturists have not promoted use of Dirca palustris L. (eastern leatherwood) despite its suite of traits valued by gardeners and landscapers. Horticultural production of D. palustris may be hindered by slow shoot growth and sensitivity of plants to edaphic conditions. Because of discrepancies in reported tolerances of D. palustris to root-zone pH, we assessed whether pH of soils supporting indigenous populations in Florida, Maine, and North Dakota corresponded to responses of seedlings from the three provenances to root-zone pH of 4.5 to 7.3 in soilless media. Regression showed that root zones at pH 5.8 promoted maximum stem length of seedlings from Florida and North Dakota, whereas root zones at pH 4.5 led to maximum stem length of seedlings from Maine. Root-zone pH 5.6 and 5.5 fostered maximum root and shoot dry weight, respectively, for seedlings from Florida, whereas root zones at pH 4.5 promoted maximum root and shoot dry weights of seedlings from Maine and North Dakota. Averaged over provenance, relative leaf greenness decreased by 62%, and foliar nitrogen, iron, manganese, and zinc decreased by 49%, 70%, 95%, and 48%, respectively, as root-zone pH increased from 4.5 to 7.3. Foliar phosphorus decreased at both low and high pH. The pH of soils where seeds were collected did not predict optimal root-zone pH for stem length or biomass accrual in soilless media; genotypes from soils with a pH of 7.4 in North Dakota did not exhibit greater tolerance to high pH than genotypes from Maine or Florida, where pH of indigenous soil was 6.1 and 5.2, respectively. Averaged over pH treatments, seedlings from Florida showed the greatest stem length and formed the most shoot biomass, whereas seedlings from North Dakota had stouter stems, greater root biomass, and greater root-to-shoot ratios than did seedlings from Florida and Maine. Our results illustrate that acidic media facilitate horticultural production of D. palustris, that further evaluation of provenance differences could facilitate selection of genotypes for horticulture, and that tolerances of genotypes to root-zone pH do not strictly correspond to the pH of soils on which they were indigenous.

Analisi esplorativa dell'effetto di soluzioni ultramolecolari di triossido di arsenico sullo sviluppo vegetativo in vitro di plantule di grano

This paper deals with an experiment in which wheat seeds were stressed with a material dose of As2 O3, and then treated with ultra-molecolar dilutions of the same substance, with and without potentization. We focused our analysis on seedling stem length during 7 days of treatment, and tried to give a thorough statistical description of the data. We applied simple nonparametric tests for comparing treated and control groups: it seems to be a significant stimulating effect when seeds are treated with the 45th decimal potency of As2 O3 . A similar effect was obtained in a previous experiment (Betti et al., 1997), and shows that our model allows a proper reproducibility of results.

Influence of Day and Night Temperatures on Sweet Pepper Seedling Development

Sweet pepper (Capsicum annuum `Resistant Giant no. 4') seedlings were grown for 6 weeks in 128-cell plug trays under 16 day/night temperature (DT/NT) regimes from 14 to 26 °C. Seedling stem length, internode length, stem diameter, leaf area, internode and leaf count, plant volume, shoot dry weight (DW), seedling index, and leaf unfolding rate (LUR) were primarily functions of average daily temperature (ADT); i.e., DT and NT had similar effects on each growth or development parameter. Compared to ADT, the difference (DIF, where DIF = DT - NT) between DT and NT had a smaller but still statistically significant effect on stem and internode length, leaf area, plant volume, stem diameter, and seedling index. DIF had no effect on internode and leaf count, shoot DW, and LUR. The root: shoot ratio and leaf reflectance were affected by DT and DIF. Positive DIF (DT higher than NT) caused darker-green leaf color than negative DIF. The node at which the first flower initiated was related to NT. The number of nodes to the first flower on pepper plugs grown at 26 C NT was 1.2 fewer than those of plants grown at 14 °C NT.

Deciduous Tree Seedling Response to Nursery Soil Amended with Composted Sewage Sludge1

Abstract The stem length of seedlings of Liriodendron tulipifera L. and Cornus florida L. was greater in plots in which screened compost, made from digested sewage sludge and wood chips, was incorporated into sandy soil nursery seedbeds at 224 tons/ha prior to sowing seeds than in unfertilized soil. L. tulipifera seedlings suffered less winter dieback when grown in soils amended with screened compost. The addition of composted sludge increased soil nutrient content, pH, and water holding capacity.