The influence of substrate on the growth and morphology of Myriophyllum exalbescens and Myriophyllum spicatum

1980 ◽  
Vol 58 (9) ◽  
pp. 1111-1118 ◽  
Author(s):  
S.G. Aiken ◽  
R. R. Picard
Keyword(s):  
Plant Material ◽  
Myriophyllum Spicatum ◽  
Growth Conditions ◽  
Leaf Length ◽  
Main Stem ◽  
Stem Cuttings ◽  
Growth Responses ◽  
Influence Of Substrate ◽  
Myriophyllum Exalbescens

Stem cuttings, 30 cm long, of Myriophyllum exalbescens Fern. and M. spicatum L. were planted in three substrates: loam, sand, and peat. Growth responses of these species were compared in three independent experiments each of a duration of 50 days. In some cases M. spicatum grew more vigorously, but the previous growth conditions for the plant material at the start of the experiment influenced the total amount of growth. In all experiments the percentage of ash in M. exalbescens was greater than in plants of M. spicatum grown in the same environment. The two species remained distinct from one another in characteristics of leaf length, number of leaf divisions, and length of internodes near the apex of the main stem. Within each species a marked relationship between morphology and substrate was observed. On the nutrient-poor substrate, sand, leaves of M. spicatum converged in appearance towards leaves of M. exalbescens grown on the nutrient-rich substrate, loam.

Vegetative Propagation of Woody Ornamentals Through Forcing of Epicormic Shoots

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 503c-503
Author(s):  
Paul H. Henry ◽  
John E. Preece
Keyword(s):  
Plant Material ◽  
Woody Plant ◽  
Clonal Plant ◽  
Light Regime ◽  
Moisture Regime ◽  
Stem Cuttings ◽  
Shrub Species ◽  
Woody Ornamentals ◽  
Ornamental Tree ◽  
Environmental Light

A propagation method is being developed that allows softwood shoots to be generated from stem sections of dormant woody plant species. These shoots, forced in the greenhouse during the winter, are subsequently collected and processed as softwood stem cuttings to produce clonal plant material. Many species in the nursery industry can only be propagated using softwood cuttings, and this technique allows propagation of these species to be initiated several months earlier than what is typically possible. Current studies involve expanded screening of ornamental tree and shrub species to determine if commercial production using this technique is feasible. Results demonstrate that many species may be propagated using this method, but that some species are more prolific than others with respect to number of softwood shoots produced. Additional studies are currently in progress to determine the environmental (light regime, moisture regime) and cultural (type of media) conditions that are optimal when producing clonal plant material via this technique.

Growth responses of Leymus chinensis (Trin.) Tzvelev to sheep saliva after defoliation

2010 ◽  
Vol 32 (4) ◽  
pp. 419 ◽  
Author(s):  
Xing Teng ◽  
Lei Ba ◽  
Deli Wang ◽  
Ling Wang ◽  
Jushan Liu
Keyword(s):  
Plant Growth ◽  
Aboveground Biomass ◽  
Field Experiments ◽  
Perennial Grass ◽  
Leaf Length ◽  
Leymus Chinensis ◽  
Growth Responses ◽  
Time Duration ◽  
Positive Effects ◽  
Leaf Weight

Many studies indicated that saliva from herbivores might be involved in plant growth responses when plants have been grazed. However, there is currently no general agreement on whether saliva can affect plant growth. Our aims were to determine the growth response of plants to sheep saliva after defoliation under diverse environmental conditions (different sward structures), and whether the effect of saliva is influenced by time (duration) after its application. We conducted field experiments with clipping treatments and the application of sheep saliva to the damaged parts of tillers to simulate sheep grazing on the perennial grass Leymus chinensis (Trin.) Tzvelev during the early growing seasons. Results demonstrated that clipping with saliva application significantly increased tiller numbers 8 weeks after treatments in comparison with clipping alone. A key finding is that the effect of sheep saliva on plant growth was short-lived. Clipping with saliva application increased leaf weight in the second week, while clipping alone had no effect. Moreover, clipping with saliva application promoted the elongation of new leaves (not the old ones) in the first week whereas clipping alone was ineffective. Results also showed that there were no differences between clipping with saliva application and clipping alone for relative height growth rate and aboveground biomass. Therefore, we concluded that saliva application to clipping treatment would produce an additional effect compared to clipping alone for the plant and the positive effects are time dependent. The additional effects primarily embodied in the individual level of plant, such as the changes of leaf weight and leaf length. Beyond the level, the effects of saliva only produced many more tiller numbers rather than the accumulation of aboveground biomass.

scholarly journals A quantitative multivariate methodology for unsupervised class identification in pistachio (Pistacia vera L.) plant leaves size

2020 ◽  
Vol 18 (4) ◽  
pp. e0208
Author(s):  
Francesca Antonucci ◽  
Rossella Manganiello ◽  
Corrado Costa ◽  
Virgilio Irione ◽  
Luciano Ortenzi ◽  
...  
Keyword(s):  
Morphological Traits ◽  
Leaf Traits ◽  
Growth Conditions ◽  
Leaf Length ◽  
Classification Model ◽  
Leaf Width ◽  
Neural Network Approach ◽  
Size Classes ◽  
Morphological Variables ◽  
Stalk Length

Aim of study: Genetic diversity of pistachio, can be evaluated by using different descriptors, as adopted in international certification systems. Mainly the descriptors are morphological traits as leaf, which represents an important organ for its sensibility to growth conditions during the expansion phase. This study adopted a rapid and quantitative non-hierarchic clustering classification (k-means), to extract size classes basing on the contemporary combination of different morphological traits (i.e., leaf stalk length, terminal leaf length, terminal leaf width and terminal leaf ratio) of a varietal collection composed by 21 pistachio cultivars.Area of study: Worldwide.Material and methods: The unsupervised non-hierarchic clustering technique was adopted to the entire samples of pistachio leaves from k=2 to k=15 for both four morphological variables (i.e., leaf stalk length, terminal leaf length, terminal leaf width and terminal leaf ratio) and three morphological variables (i.e., terminal leaf length, terminal leaf width and terminal leaf ratio).Main results: A classification model only on the three morphological variables (for results of statistical analysis in which the groups resulted to be more separated and different for all the variables), with k= 5 (five groups), was constructed using a non-linear artificial neural network approach. The percentages of bad prediction in both training and testing resulted equal to 0%. The “terminal leaf length” returned the higher impact (44.89%).Research highlights: The contemporary combination of different morphological leaf traits, allowed to create an automatic classification of size classes of great importance for cultivar identification and comparison.

scholarly journals Producing Black Pepper (Piper Nigrum L. cv. ‘Kuching’) Rootstock in a Deep-Water Culture Hydroponic System

2021 ◽  
Vol 11 (2) ◽  
pp. 88-97
Author(s):  
Jie Hung King ◽  
Babirye Khadijah ◽  
Kian Huat Ong
Keyword(s):  
Root Length ◽  
Adventitious Roots ◽  
Silicate Solution ◽  
Growth Conditions ◽  
Black Pepper ◽  
Nutrient Composition ◽  
Piper Nigrum ◽  
Pepper Plant ◽  
Stem Cuttings ◽  
Hoagland Solution

Stem cutting is the common planting material for black pepper (Piper nigrum L.) farmers mainly because the method is cheap, easy to obtain, and produces satisfactory number of new plantlets, which are relatively genetically uniform to their parent. However, soil propagation of stem cuttings renders both the stem and developing roots susceptible to soil borne pathogens, ultimately compromising the quality of the plant. Good quality rootstock of the new plant promotes faster, safer, and better black pepper plant establishment. Hydroponic farming thus offers a good platform for producing quality rootstock of the new plants and has gained importance to many farmers due to its flexibility in manipulating plant growth conditions and timely pathogen management, thus safer, healthier, and faster growth. This study investigated the growing media suitable for rootstock growth of P. nigrum L. cv. ‘Kuching’ and compared the rooting ability between stem cuttings with adventitious roots at the time of planting and stem cuttings without any root at the time of planting. In a laboratory setting, a total of 210 stem cuttings were hydroponically planted in seven nutrient compositions, with each nutrient composition containing an equal number of stem cuttings with adventitious roots at the time of planting and stem cuttings without any root at the time of planting. Hoagland solution supplemented with 0.005 mM potassium silicate solution (T4) and Hoagland solution supplemented with 2 mM salicylic acid solution (T6) showed faster root initiation whereas T1 (Hoagland solution only) produced the highest increment in root length followed by T6. The least suitable nutrient composition was T5 [T4 + 6 mL of 1 M Ca (NO3)2.4H2O solution]. The total number of roots was highest in plants from stem cuttings which had some adventitious roots at the time of planting, whereas roots in plants from stem cuttings which did not have any root at the time of planting, increased in root length faster than plants withstem cuttings which had adventitious roots at the time of planting.

scholarly journals Variations in Morphological Characters and Antioxidant Potential of Different Plant Parts of Four Ziziphus Mill. Species from the Cholistan

Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2734
Author(s):  
Muhammad Umair Riaz ◽  
Muhammad Ali Raza ◽  
Amjad Saeed ◽  
Mukhtar Ahmed ◽  
Tanveer Hussain
Keyword(s):  
Large Scale ◽  
Positive Impact ◽  
Dry Weight ◽  
Growth Conditions ◽  
Morphological Characters ◽  
Leaf Length ◽  
Important Species ◽  
Medicinal Uses ◽  
Leaf Petiole ◽  
Plant Parts

Genus Ziziphus (Z.) contains various important species in tropical and subtropical regions that are globally famous for their food and medicinal uses. However, no comprehensive study was available on the morphology and phytochemistry of Ziziphus species, mainly under different growth conditions, i.e., irrigated and desert (Cholistan). Therefore, this study was carried out to evaluate the morphological and phytochemical characteristics of Ziziphus species, i.e., Z. jujuba, Z. mauritiana, Z. spina-christi, and Z. nummularia, found in the irrigated and desert conditions. Our results revealed significant variations for most of the measured parameters, showing a large-scale diversity among Ziziphus species under irrigated and desert conditions. Specifically, Ziziphus species showed better morphology of all measured parameters of leaves and fruits under irrigated conditions compared to desert conditions, indicating that the optimum water availability in irrigated conditions improved the morphological parameters of Z. species. Meanwhile, among all Ziziphus species, the maximum leaf length (7.4 cm), leaf width (4.1 cm), leaf area (30.6 cm2), and leaf petiole length (1.3 cm) were observed for Z. jujuba, and the highest leaf dry weight (55.4%) was recorded for Z. mauritiana. Similarly, the highest fruit length (3.9 cm), fruit stalk length (1.5 cm), fruit diameter (3.6 cm), fruit width (3.8 cm), fruit area (66.1 cm2), seed length (2 cm), and seed diameter (1.1 cm) were measured for species Z. jujuba, while the maximum fruit dry weight (49.9%) and seed width (1.4 cm) were recorded for species Z. nummularia. Interestingly, compared to irrigated conditions, higher values of bioactive contents, i.e., phenol, flavonoid, and antioxidant activity, in fruits and leaves of Ziziphus species under desert conditions indicated the positive impact of desert climate on the phytochemistry of the Z. plants. Among Ziziphus species, Z. nummularia accumulated the maximum fruit phenols (304.4 mg GAE/100 g), leaf phenols (314.2 mg GAE/100 g), fruit flavonoids (123.7 mg QE/100 g), and leaf flavonoids (113.4 mg QE/100 g). Overall, this study demonstrated the significant morphological and phytochemical variations of the Ziziphus species under irrigated and desert conditions, which could be utilized for future studies to improve the production and medicinal potential of the Ziziphus, especially in desert areas.

The Arabidopsis selenium-binding protein confers tolerance to toxic levels of selenium

2005 ◽  
Vol 32 (10) ◽  
pp. 881 ◽  
Author(s):  
Adamantia Agalou ◽  
Andreas Roussis ◽  
Herman P. Spaink
Keyword(s):  
Transgenic Plants ◽  
Gene Silencing ◽  
Binding Protein ◽  
Normal Growth ◽  
Growth Conditions ◽  
Growth Responses ◽  
Wild Type ◽  
Selenium Toxicity ◽  
Transcript Levels ◽  
Expression Levels

In the Arabidopsis genome there are three highly conserved homologues of the mammalian 56-kD selenium-binding protein (SBP). To study the function of SBP in this model plant, we used a transgenic approach by constitutively overexpressing and down-regulating the endogenous Atsbp1 gene. In the latter case, we employed both a conventional antisense method and gene silencing by intron-containing hairpin RNAs. Atsbp1-overexpressing and silenced plants were phenotypically normal, under standard growth conditions, when compared with wild type plants. Transgenic plants exhibited different growth responses to exogenously supplied selenite, which correlated with the expression levels of Atsbp1. Plants with increased Atsbp1 transcript levels showed enhanced tolerance to selenite, while plants with reduced levels were more sensitive. Our results indicate that, although Atsbp1 does not play a detectable role in the regulation of developmental processes under normal growth conditions, it appears to be involved in processes controlling tolerance of Arabidopsis to selenium toxicity.

Growth Responses in Sorghum and Wheat Induced by Glyphosate

Weed Science ◽  
1977 ◽  
Vol 25 (3) ◽  
pp. 238-240 ◽  
Author(s):  
J.R. Baur ◽  
R.W. Bovey ◽  
J.A. Veech
Keyword(s):  
Foliar Application ◽  
Normal Growth ◽  
Growth Zone ◽  
Growth Conditions ◽  
Optimum Growth ◽  
Growth Responses ◽  
Fresh Weight ◽  
Optimum Growth Temperature ◽  
Chamber Studies ◽  
Growth Chamber Studies

Foliar application of 2.8 μg/plant of glyphosate [N-(phosphonomethyl)glycine] to greenhouse grown sorghum [Sorghum bicolor (L.) Moench ‘Tophand’] seedlings resulted in increased fresh weight. As glyphosate levels were increased to 11.2 μg/plant, diameter of the basal growth zone increased while fresh weight decreased. In growth chamber studies with sorghum and wheat [Triticum aestivum (L.) ‘Era’] seedlings, glyphosate caused the greatest reduction in fresh weight at the optimum growth temperatures for both species. Glyphosate inhibited normal production of basal buds in wheat at the optimum growth temperature and stimulated bud production at temperatures above the optimum. Under normal growth conditions, basal buds in sorghum do not develop; however, application of glyphosate stimulated basal bud development under normal and above-normal temperature conditions. Histochemical analysis of malate dehydrogenase activity in apical meristem tissue of treated sorghum seedlings indicated that growth of the apex was normal and viable.

Stem and leaf growth of alpine sun and prairie shade ecotypes of Stellaria longipes under different photoperiods: role of ethylene

2006 ◽  
Vol 84 (9) ◽  
pp. 1496-1502 ◽  
Author(s):  
Linda J. Walton ◽  
Leonid V. Kurepin ◽  
David M. Reid ◽  
C.C. Chinnappa
Keyword(s):  
Leaf Growth ◽  
Stem Elongation ◽  
Leaf Length ◽  
Leaf Expansion ◽  
Alpine Plants ◽  
Growth Responses ◽  
Stellaria Longipes ◽  
Length And Area ◽  
Radiation Conditions

Plant ecotypes of Stellaria longipes Goldie from competitive, shade-adapted prairie habitat and less competitive, nonshaded alpine habitat were subjected to shortened or extended photoperiod conditions. Increasing daylength was positively correlated to increased stem elongation in both ecotypes. Leaf length and area for shade (prairie) plants was significantly altered with increased photoperiods, whereas sun (alpine) plants exhibited minimal leaf expansion in response to increased photoperiod. Increased ethylene evolution in the alpine genotype during rapid stem elongation and extended photoperiods suggests that ethylene plays a growth regulatory role in this sun-adapted genotype. The prairie genotype evolved less ethylene during these same periods, indicating either a diminished requirement for elevated ethylene to effect elongation and leaf expansion responses or possibly increased ethylene sensitivity because of interactions with other hormones, such as gibberellin or auxin. The sun genotype consistently produced more ethylene than the shade genotype under all photoperiod treatments. We conclude that photoperiod alters stem elongation and leaf expansion responses; similar trends were observed for extended photoperiods as were observed for shaded conditions, specifically low light intensity (photosynthetically active radiation) conditions. Further, ethylene levels altered during these responses, especially in sun-adapted alpine plants, which suggests that ethylene is involved in these growth responses.

Adaptive Growth Responses of Listeria monocytogenes to Acid and Osmotic Shifts above and across the Growth Boundaries

2011 ◽  
Vol 74 (1) ◽  
pp. 78-85 ◽  
Author(s):  
C.-I. A. BELESSI ◽  
Y. LE MARC ◽  
S. I. MERKOURI ◽  
A. S. GOUNADAKI ◽  
S. SCHVARTZMAN ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Cell Injury ◽  
Meat Products ◽  
Injury Rate ◽  
Growth Conditions ◽  
High Survival ◽  
Growth Responses ◽  
Survival Capacity ◽  
Lag Times ◽  
Fermented Dairy

The effect of acid and osmotic shifts on the growth of Listeria monocytogenes was evaluated at 10°C. Two types of shifts were tested: (i) within the range of pH and water activity (aw) levels that allow growth of L. monocytogenes and (ii) after habituation at no-growth conditions back to growth-permitting conditions. A L. monocytogenes cheese isolate, with high survival capacity during cheesemaking, was inoculated (102 CFU/ml) in tryptic soy broth supplemented with 0.6% yeast extract at six pH levels (5.1 to 7.2; adjusted with lactic acid) and 0.5% NaCl (aw 0.995), or four aw levels (0.995 to 0.93, adjusted with 0.5 to 10.5% NaCl) at pH 7.2 and grown to early stationary phase. L. monocytogenes was then shifted (at 102 CFU/ml) to each of the aforementioned growth-permitting pH and aw levels and incubated at 10°C. Shifts from no-growth to growth-permitting conditions were carried out by transferring L. monocytogenes habituated at pH 4.9 or aw 0.90 (12.5% NaCl) for 1, 5, and 10 days to all pH and aw levels permitting growth. Reducing aw or pH at different levels in the range of 0.995 to 0.93 and 7.2 to 5.1, respectively, decreased the maximum specific growth rate of L. monocytogenes. The lag time of the organism increased with all osmotic downshifts, as well as by the reduction of pH to 5.1. Conversely, any type of shift within pH 5.5 to 7.2 did not markedly affect the lag times of L. monocytogenes. The longer the cells were incubated at no-growth aw (0.90), the faster they initiated growth subsequently, suggesting adaptation to osmotic stress. Conversely, extended habituation at pH 4.9 had the opposite effect on subsequent growth of L. monocytogenes, possibly due to cell injury. These results suggest that there is an adaptation or injury rate induced at conditions inhibiting the growth of the pathogen. Thus, quantifying adaptation phenomena under growth-limiting environments, such as in fermented dairy and meat products or products preserved in brine, is essential for reliable growth simulations of L monocytogenes during transportation and storage of foods.

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