Vegetative Reproduction Potential of Common Purslane (Portulaca oleracea)

2011 ◽  
Vol 25 (4) ◽  
pp. 694-697 ◽  
Author(s):  
Christopher A. Proctor ◽  
Roch E. Gaussoin ◽  
Zachary J. Reicher
Keyword(s):  
Leaf Growth ◽  
Vegetative Reproduction ◽  
Reproductive Capacity ◽  
Plant Tissues ◽  
Stem Cuttings ◽  
Stem Node ◽  
Greenhouse Study ◽  
Mechanical Methods ◽  
Stem Internode ◽  
Common Purslane

Common purslane is a widely distributed summer annual weed. It can reproduce vegetatively from stem cuttings by forming adventitious roots from the cut end of the stem. Apart from large stem cuttings, it is unclear whether purslane cuttings of various plant tissues differ in their ability to reproduce asexually. The objective of the study was to determine the survival and asexual reproductive capacity of purslane cuttings. A greenhouse study evaluated three cuttings from two stem locations and a leaf from one stem location for their survival and new leaf growth after 21 d. Cuttings included a stem node with either leaves attached or removed and a stem internode, all from proximal and distal stem locations relative to the root crown, and a leaf from a proximal stem node. Stem node cuttings had ≥ 70% survival, whereas internodes had 0% survival. Nodes with leaves attached further increased survival by > 20%. The location of the cutting on the main stem did not affect survival. Only noded cuttings produced new leaves, and cuttings with leaves attached produced the most new leaves. For purslane to vegetatively reproduce, nodes on stem cuttings are required, and the presence of leaves on the cutting improves the survival and new leaf growth of cuttings. Therefore, mechanical methods of weed control that chop and spread purslane leaves and stems might not be effective and could ultimately increase weed populations.

Preemergence Herbicide and Glyphosate Effects on Seedling Diseases in Glyphosate-Resistant Cotton

2005 ◽  
Vol 19 (2) ◽  
pp. 312-318 ◽  
Author(s):  
Joseph H. Pankey ◽  
James L. Griffin ◽  
Patrick D. Colyer ◽  
Raymond W. Schneider ◽  
Donnie K. Miller
Keyword(s):  
Field Study ◽  
Disease Severity ◽  
Field Experiments ◽  
Leaf Growth ◽  
Inhibitory Effect ◽  
Growth Stages ◽  
Seedling Disease ◽  
Greenhouse Study ◽  
Herbicide Treatments ◽  
Seedling Diseases

Field experiments were conducted to evaluate the influence of preemergence (PRE) herbicides metolachlor at 1,700 g ai/ha, pyrithiobac at 70 g ai/ha, or pendimethalin at 840 g ai/ha applied alone or with fluometuron at 1,300 g ai/ha and glyphosate postemergence (POST) at 840 g ai/ha on seedling diseases in glyphosate-resistant cotton. Hypocotyl disease severity both years averaged across PRE herbicide treatments was greater after glyphosate application to four-leaf cotton than cotyledon cotton. The PRE herbicide treatments, particularly those including fluometuron, increased root and hypocotyl disease ratings compared with a nontreated control, and a sequential application of glyphosate did not further increase disease severity. Greenhouse experiments using soil infested withRhizoctonia solaniconfirmed findings from the field study showing that PRE herbicides can predispose cotton to greater seedling disease injury with no increased seedling disease severity associated with application of glyphosate. In the field study, glyphosate applied at cotyledon or four-leaf growth stages decreased disease severity on cotton hypocotyls both years. This inhibitory effect of glyphosate was less evident in the greenhouse study and may have been related to species of fungi present, infestation level, and differences in environmental conditions when compared with the field.

The reproduction of Cardamine pratensis L. and Cardamine palustris Peterman particularly in relation to their specialized foliar vivipary, and its deflexion of the constraints of natural selection

1965 ◽  
Vol 163 (992) ◽  
pp. 321-342 ◽  
Keyword(s):  
Natural Selection ◽  
Experimental Evidence ◽  
High Efficiency ◽  
Leaf Surface ◽  
Vegetative Reproduction ◽  
Reproductive Capacity ◽  
Vegetative Multiplication ◽  
Survival Potential ◽  
Cardamine Pratensis

Data and experimental evidence are furnished regarding the reproductive capacity of Cardamine palustris Peterman and C. pratensis L. s. s . which demonstrate the paramount importance for these species of vegetative reproduction by plantlets arising from the leaf surface under conditions that were formerly prevalent. The low productivity of seed is attributed to selfincompatibility and diverse other forms of sterility and the severe competition in the closed communities these species occupy. Experiments indicate the high efficiency of the vegetative multiplication and this, it is suggested, has been accompanied by a relaxation of the restraints normally imposed by natural selection upon reproduction by seed, thus permitting the perpetuation of types that would otherwise have insufficient survival potential.

scholarly journals Germination ecology of wild and domesticated Ensete ventricosum: Evidence for maintenance of sexual reproductive capacity in a vegetatively propagated perennial crop

2020 ◽  
Author(s):  
Solomon Tamrat ◽  
James S. Borrell ◽  
Eleni Shiferaw ◽  
Simon Kallow ◽  
Rachael M. Davies ◽  
...  
Keyword(s):  
Seed Weight ◽  
Vegetative Reproduction ◽  
Germplasm Conservation ◽  
Crop Diversity ◽  
Reproductive Capacity ◽  
Perennial Crop ◽  
Ensete Ventricosum ◽  
Diurnal Range ◽  
Significant Difference ◽  
Germination Behaviour

ABSTRACTPREMISELoss of sexual reproductive capacity has been proposed as a syndrome of domestication in vegetatively propagated crops, but there are relatively few examples from agricultural systems. Compared to sexually propagated crops banked as seeds, vegetative crop diversity is typically conserved in living collections that are more costly and insecure. This vulnerability may disproportionately impact tropical crop diversity where vegetative reproduction predominates. In this study we assess sexual reproductive capacity in wild (sexual) and domesticated (vegetative) populations of enset (Ensete ventricosum (Welw.) Cheesman), a giant tropical banana relative and Ethiopian food security crop.METHODSWe harvested seeds from 20 wild and domesticated enset to survey variation in seed weight, viability, external and internal morphology. We germinated seeds across a range of constant and alternating temperature regimes to characterise optimum germination requirements, and evaluate differences in performance.KEY RESULTSWe found no significant difference between wild and domesticated enset seed viability, days to germination and internal morphological traits. However, we report a significant and unexpected shift in seed weight and germination behaviour, with seed from domesticated plants responding to cooler temperatures with greater diurnal range. Shifts in germination behaviour appear concordant with a climatic envelope shift in the domesticated distribution.CONCLUSIONSOur findings suggest sexual reproductive capacity has been maintained despite long-term near-exclusive vegetative propagation in domesticated enset. Furthermore, certain traits such as germination behaviour, may be under continued selection through rare sexually reproductive events. Improved understanding of sexual propagation in vegetative crops may have applications in germplasm conservation and plant breeding.

scholarly journals VEGETATIVE REPRODUCTION OF POPLAR BASHKIR PYRAMIDAL BEREZIN-LEVASHOV (POPULUS NIGRA L. × P. NIGRA F. ITALICA DUROI) IN THE CONDITIONS OF THE EDUCATIONAL EXPERIMENTAL FARM OF UFA LEMONARIUM

2020 ◽  
Vol 38 (4) ◽  
pp. 104-113
Author(s):  
L.N. Blonskaya ◽  
◽  
K.M. Agliullina ◽  
Keyword(s):  
Root System ◽  
Root Formation ◽  
Vegetative Reproduction ◽  
Ornamental Plants ◽  
Hybrid Poplar ◽  
Stem Cuttings ◽  
Rooted Cuttings ◽  
Planting Material ◽  
And Control ◽  
Practical Recommendations

This article examines the vegetative reproduction of a hybrid poplar of the Bashkir selection by winter stem cuttings in a greenhouse with the use of growth and root formation stimulants. The issue of obtaining in the required volumes of standard planting material of ornamental plants is currently very relevant, especially for the Bashkir pyramidal poplar, for which vegetative reproduction is the only possible option, since there are only male specimens of this hybrid, as at the stage of selection were destroyed females. To obtain exact copies of the mother plant, cuttings are the best way of propagation. The article discusses the use of 3 growth stimulants and control (without stimulants), describes the biometric characteristics of the obtained saplings, characterizes the length of the root system, the time for rooting, survival of rooted saplings. Identified the most effective preparations and conditions for growing saplings. The conducted research makes it possible to develop practical recommendations for the cultivation of rooted cuttings of the Bashkir pyramidal poplar in a greenhouse.

scholarly journals Embryological features, pollen and seed viability of Arnica montana (Asteraceae) – a threatened endemic species in Europe

2016 ◽  
Vol 75 (1) ◽  
pp. 39-44 ◽  
Author(s):  
Elina Yankova-Tsvetkova ◽  
Petka Yurukova-Grancharova ◽  
Georgi Baldjiev ◽  
Antonina Vitkova
Keyword(s):  
Sexual Reproduction ◽  
Endemic Species ◽  
Vegetative Reproduction ◽  
Seed Viability ◽  
Embryological Study ◽  
Mature Pollen ◽  
Reproductive Capacity ◽  
Mode Of Reproduction ◽  
Arnica Montana ◽  
High Viability

Abstract The embryological features, mode of reproduction and reproductive capacity (pollen and seed viability) on two naturalized populations of Arnica montana in Bulgaria were studied. The embryological study shows that A. montana is a facultative apomictic species in which sexual reproduction predominates. In this species, it was established that there is a comparatively high viability of the mature pollen and embryos, which enables the successful realization of its reproductive capacity. The results of the study on A. montana reveal that both sexual and asexual vegetative reproduction with rhizomes undoubtedly play more important roles than the apomixis (namely diplospory) for support and preservation of the populations.

Microscopy studies of powdery mildew on summer squash

1991 ◽  
Vol 49 ◽  
pp. 520-521
Author(s):  
John S. Gardner ◽  
W. M. Hess
Keyword(s):  
Powdery Mildew ◽  
Tip Growth ◽  
Hyphal Growth ◽  
Plant Tissues ◽  
Vegetative Hypha ◽  
Powdery Mildews ◽  
Summer Squash ◽  
Conidial Formation ◽  
Polar Tip Growth ◽  
Short Conidiophore

Powdery mildews are characterized by the appearance of spots or patches of a white to grayish, powdery, mildewy growth on plant tissues, entire leaves or other organs. Ervsiphe cichoracearum, the powdery mildew of cucurbits is among the most serious parasites, and the most common. The conidia are formed similar to the process described for Ervsiphe graminis by Cole and Samson. Theconidial chains mature basipetally from a short, conidiophore mother-cell at the base of the fertile hypha which arises holoblastically from the conidiophore. During early development it probably elongates by polar-tip growth like a vegetative hypha. A septum forms just above the conidiophore apex. Additional septa develop in acropetal succession. However, the conidia of E. cichoracearum are more doliform than condia from E. graminis. The purpose of these investigations was to use scanning electron microscopy (SEM) to demonstrate the nature of hyphal growth and conidial formation of E. cichoracearum on field-grown squash leaves.

Localization of acid phosphatases in root cap of rice plant

1991 ◽  
Vol 49 ◽  
pp. 224-225
Author(s):  
Y. R. Chen ◽  
Y. F. Huang ◽  
W. S. Chen
Keyword(s):  
Rice Plant ◽  
Developmental Stages ◽  
Uranyl Acetate ◽  
Root Cap ◽  
Plant Tissues ◽  
Acid Phosphatases ◽  
Root Tips ◽  
Buffer Solution ◽  
Cacodylate Buffer ◽  
Ethanol Series

Acid phosphatases are widely distributed in different tisssues of various plants. Studies on subcellular localization of acid phosphatases show they might be present in cell wall, plasma lemma, mitochondria, plastid, vacuole and nucleus. However, their localization in rice cell varies with developmental stages of cells and plant tissues. In present study, acid phosphatases occurring in root cap are examined.Sliced root tips of ten-day-old rice(Oryza sativa) seedlings were fixed in 0.1M cacodylate buffer containing 2.5% glutaraldehyde for 2h, washed overnight in same buffer solution, incubated in Gomori's solution at 37° C for 90min, post-fixed in OsO4, dehydrated in ethanol series and finally embeded in Spurr's resin. Sections were doubly stained with uranyl acetate and lead citrate, and observed under Hitachi H-600 at 75 KV.

Ultrastructural Effects of Acute Kepone Treatment in Rats

1976 ◽  
Vol 34 ◽  
pp. 286-287
Author(s):  
Richard L. Klein ◽  
Åsa K. Thureson-Klein ◽  
Harihara M. Mehendale
Keyword(s):  
Neurological Disorders ◽  
Corn Oil ◽  
Preliminary Investigation ◽  
Reproductive Capacity ◽  
Ultrastructural Changes ◽  
Lipid Deposition ◽  
Severe Toxicity ◽  
Sprague Dawley ◽  
Ether Anesthesia ◽  
Sprague Dawley Rats

KeponeR (decachlorooctahydro-1,3,4-metheno-2H-cyclobuta[cd]pentalen-2-one) is an insecticide effective against ants and roaches. It can cause severe toxicity in fishes, birds, rodents and man. Prominent effects include hepatic lipid deposition and hypertrophy, impairment of reproductive capacity and neurological disorders. Mitochondrial oligomycin-sensitive Mg2+-ATPase is also inhibited. The present study is a preliminary investigation of tissue ultrastructural changes accompanying physiological signs of acute toxicity, which after two days treatment include: pronounced hypersensitivity and tremor, various degrees of anorexia and adipsia, and decreased weight gain.Three different series of adult male Sprague-Dawley rats (Charles River or CD-I) were treated by intubation with Kepone in corn oil at a dose of 50 mg per kg for 3 successive days or at 200 ppm in food for 8 days. After ether anesthesia, rats were immediately perfused via a cannula in the left ventricle with 4% p-formaldehyde and 0.5% glutaraldehyde in Millonig's phosphate buffer at pH 7.2 for 20-30 min at 22°C.

Cryosectioning plant roots prepared by high-pressure freezing

1987 ◽  
Vol 45 ◽  
pp. 662-663
Author(s):  
R.E. Crang ◽  
M. Mueller ◽  
K. Zierold
Keyword(s):  
High Pressure ◽  
Cell Walls ◽  
Plant Tissues ◽  
Ice Crystal ◽  
High Pressure Freezing ◽  
Vitreous State ◽  
Radial Depth ◽  
Irregular Topography ◽  
Considerable Depth ◽  
Conventional Freezing

Obtaining frozen-hydrated sections of plant tissues for electron microscopy and microanalysis has been considered difficult, if not impossible, due primarily to the considerable depth of effective freezing in the tissues which would be required. The greatest depth of vitreous freezing is generally considered to be only 15-20 μm in animal specimens. Plant cells are often much larger in diameter and, if several cells are required to be intact, ice crystal damage can be expected to be so severe as to prevent successful cryoultramicrotomy. The very nature of cell walls, intercellular air spaces, irregular topography, and large vacuoles often make it impractical to use immersion, metal-mirror, or jet freezing techniques for botanical material.However, it has been proposed that high-pressure freezing (HPF) may offer an alternative to the more conventional freezing techniques, inasmuch as non-cryoprotected specimens may be frozen in a vitreous, or near-vitreous state, to a radial depth of at least 0.5 mm.

The role of silicon in forages: A quantitative X-Ray study

1987 ◽  
Vol 45 ◽  
pp. 416-417
Author(s):  
Janet H. Woodward ◽  
D. E. Akin
Keyword(s):  
Sodium Acetate ◽  
Dry Matter ◽  
Acetate Buffer ◽  
Plant Tissues ◽  
Sodium Acetate Buffer ◽  
X Ray ◽  
Dry Matter Digestibility ◽  
Percent Composition

Silicon (Si) is distributed throughout plant tissues, but its role in forages has not been clarified. Although Si has been suggested as an antiquality factor which limits the digestibility of structural carbohydrates, other research indicates that its presence in plants does not affect digestibility. We employed x-ray microanalysis to evaluate Si as an antiquality factor at specific sites of two cultivars of bermuda grass (Cynodon dactvlon (L.) Pers.). “Coastal” and “Tifton-78” were chosen for this study because previous work in our lab has shown that, although these two grasses are similar ultrastructurally, they differ in in vitro dry matter digestibility and in percent composition of Si.Two millimeter leaf sections of Tifton-7 8 (Tift-7 8) and Coastal (CBG) were incubated for 72 hr in 2.5% (w/v) cellulase in 0.05 M sodium acetate buffer, pH 5.0. For controls, sections were incubated in the sodium acetate buffer or were not treated.

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