Influence of Day and Night Temperature on Development of Sweet Pepper Seedlings

Sweet pepper (Capsicum annuum `Resistant Giant #4') seedlings were grown in 128-cell plug trays under 16 day/night temperature (DT/NT) regimes from 14 to 26C. In this temperature range, plant stem height, leaf unfolding rate, plant volume, internode length, stem diameter, leaf area, and shoot dry weight were primarily functions of average daily temperature (ADT). Internode length increased as ADT or the difference between day and night temperature (DIF) increased. The root-to-shoot ratio decreased linearly as DT increased and was not significantly affected by NT. Leaves were darker green under positive DIF than negative DIF temperature regimes. Increasing NT from 14 to 26C reduced the node at which the first flower appeared by an average of 1.2 nodes. Percent abortion of the first flower increased as DT increased. Plant quality, as defined by seedling index [(dry weight × stem diameter)/internode length], increased as DIF became more negative.

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Influence of Day and Night Temperatures on Sweet Pepper Seedling Development

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.121.4.699 ◽

1996 ◽

Vol 121 (4) ◽

pp. 699-704 ◽

Cited By ~ 4

Author(s):

Yaping Si ◽

Royal D. Heins

Keyword(s):

Leaf Area ◽

Dry Weight ◽

Sweet Pepper ◽

Internode Length ◽

Stem Diameter ◽

Stem Length ◽

Shoot Dry Weight ◽

Shoot Ratio ◽

Root Shoot Ratio ◽

The Difference

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.

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Temperature and Duration of Pretreatment Effects on Growth and Development of Geraniums

HortScience ◽

10.21273/hortsci.27.3.216 ◽

1992 ◽

Vol 27 (3) ◽

pp. 216-217

Author(s):

Serge Gagnon ◽

Blanche Dansereau

Keyword(s):

Leaf Area ◽

Plant Height ◽

Growth And Development ◽

Dry Weight ◽

Rapid Adaptation ◽

Night Temperature ◽

Flower Buds ◽

Shoot Dry Weight ◽

Temperature Regimes ◽

Pretreatment Effects

Geranium seedlings (Pelargonium ×hortorum Bailey `Smash Hit Red') were given various cold pretreatments (CP) to obtain more rapid adaptation to constant or split-night temperature regimes. The six following CP were used: either 13C or 17/13C for 5, 10, or 15 days. The effect of these CP given at seedling stage was compared with that of control plants held at 17C at night. The CP did not significantly increase the time to first visible flower buds or to anthesis. The number of flowering stems, plant height, shoot dry weight, and leaf area of control plants were not significantly different from plants receiving CP.

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The relationship between multiple leaders and mechanical and frost damage to the apical meristem of Scots pine seedlings

Canadian Journal of Forest Research ◽

10.1139/x90-041 ◽

1990 ◽

Vol 20 (3) ◽

pp. 280-284 ◽

Cited By ~ 7

Author(s):

Jarmo K. Holopainen

Keyword(s):

Scots Pine ◽

Apical Meristem ◽

Dry Weight ◽

Frost Damage ◽

Night Temperature ◽

Shoot Dry Weight ◽

Frost Injury ◽

Pine Seedlings ◽

Before And After ◽

Multiple Leaders

The responses of young Scots pine seedlings to mechanical apical meristem damage before and after 4 nights exposure to minimum night temperatures of −2.2 and −6.7 °C in controlled environment growth chambers were compared with control seedlings that were subjected or not to apical meristem damage and exposed to a minimum night temperature of 12 °C. The feeding damage caused by Lygus bugs was simulated by piercing the apical meristem of young pine seedlings with a hypodermic syringe needle and injecting a small drop of distilled water into the wound. At −6.7 °C increased numbers of dead seedlings were found. The proportion of seedlings with multiple leaders greatly increased after piercing, and about half of the seedlings subjected to the apical meristem damage had multiple leaders. The proportion of seedlings with multiple leaders and the number of leader shoots per seedling did not differ among seedlings subjected to apical meristem damage before or after the frost exposure. Short and twisted primary needles occurred in the basal parts of the new shoots in the seedlings with multiple leaders. Seedlings with necrotic needles were most often found after exposure to the night temperature of −6.7 °C. Shoot dry weight and length were significantly lower in seedlings subjected to apical meristem damage after frost exposure than in seedlings subjected to apical meristem damage before frost exposure or to no frost exposure. The results suggest that an increased reduction in growth is to be expected if Lygus bug attacks occur on pine seedlings that already suffer from frost injury.

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Response of Taxus times media var. densiformis to inoculation with arbuscular mycorrhizal fungi

Canadian Journal of Forest Research ◽

10.1139/x97-182 ◽

1998 ◽

Vol 28 (1) ◽

pp. 150-153

Author(s):

J N Gemma ◽

R E Koske ◽

E M Roberts ◽

S Hester

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Glomus Intraradices ◽

Arbuscular Mycorrhizal ◽

Dry Weight ◽

Root Systems ◽

Stem Diameter ◽

Rooted Cuttings ◽

Shoot Dry Weight ◽

Mycorrhizal Plants

Rooted cuttings of Taxus times media var. densiformis Rehd. were inoculated with the arbuscular mycorrhizal fungi Gigaspora gigantea (Nicol. & Gerd.) Gerd. & Trappe or Glomus intraradices Schenck and Smith and grown for 9-15 months in a greenhouse. At the completion of the experiments, leaves of inoculated plants contained significantly more chlorophyll (1.3-4.1 times as much) than did noninoculated plants. In addition, mycorrhizal plants had root systems that were significantly larger (1.3-1.4 times) and longer (1.7-2.1 times) than nonmycorrhizal plants, and they possessed significantly more branch roots (1.3-2.9 times). No differences in stem diameter and height or shoot dry weight were evident at the end of the experiments, although the number of buds was significantly greater in the cuttings inoculated with G. intraradices after 15 months.

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AVOCADO SEEDLINGS MULTIPLE STEMS PRODUCTION

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452016221 ◽

2016 ◽

Vol 38 (2) ◽

Cited By ~ 1

Author(s):

MARCUS VINICIUS SANDOVAL PAIXÃO ◽

JOSÉ CARLOS LOPES ◽

EDILSON ROMAIS SCHMILDT ◽

RODRIGO SOBREIRA ALEXANDRE ◽

CAROLINE MERLO MENEGHELLI

Keyword(s):

Root Length ◽

Dry Weight ◽

Adventitious Rooting ◽

Dry Mass ◽

Stem Diameter ◽

Experimental Unit ◽

Shoot Height ◽

Shoot Dry Weight ◽

Federal Institute ◽

Multiple Stems

ABSTRACT This study aimed to evaluate the potential of multi-stems in avocado seeds according to their mass as well as the adventitious rooting of multi-stem budding with or without the use of auxin. The research was carried out at the Vegetation House of Federal Institute of Espírito Santo, Campus Santa Teresa -ES, with seeds of different masses: <60 g, 61 to 80 g, 81 to 100 g and >100 g, in which each experimental unit was made of five seeds, distributed within five repetitions, under a completely randomized design. The seeds were put to germinate and the percentage number of emergence and multiple stems were evaluated. After 150 days, the following evaluations were carried out: survival of rooted cuttings; number of leaves; stem diameter; root length; root volume; root and shoot fresh mass; root and shoot dry mass; shoot height; absolute growth and shoot growth rate; shoot dry weight/root dry mass ratio; shoot height/stem diameter ratio; shoot height/root length and Dickson's quality index ratio. Avocado seeds with mass over 100 g and between 81-100 g presented higher percentage of multiple stems. Rods over 20 cm that were not treated with IBA (indole-3-butyric acid) resulted on avocado plants of better quality. The use of IBA (2000 mg L-1) does not affect the rooting and growth of avocado's multi-stem plants.

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Reproducibility of suppression of Pythium wilt of cucumber by compost

Agricultural and Food Science ◽

10.23986/afsci.41471 ◽

2014 ◽

Vol 23 (3) ◽

pp. 236-245 ◽

Cited By ~ 7

Author(s):

Mauritz Vilhelm Vestberg ◽

Sanna Kukkonen ◽

Päivi Parikka ◽

Dan Yu ◽

Martin Romantschuk

Keyword(s):

Raw Materials ◽

Dry Weight ◽

Shoot Height ◽

Bacterial Diseases ◽

Sphagnum Peat ◽

Shoot Dry Weight ◽

Suppressive Capacity ◽

The Difference ◽

Set Up

There is increasing global interest in using compost to suppress soil-borne fungal and bacterial diseases and nematodes. We studied the reproducibility of compost suppressive capacity (SC) against Pythium wilt of cucumber using nine composts produced by the same composting plant in 2008 and 2009. A bioassay was set up in a greenhouse using cucumber inoculated with two strains of Pythium. The composts were used as 20% mixtures (v:v) of a basic steam-sterilized light Sphagnum peat and sand (3:1, v:v). Shoot height was measured weekly during the 5-week experiment. At harvest, the SC was calculated as the % difference in shoot dry weight (DW) between non-inoculated and inoculated cucumbers. The SC was not affected by year of production (2008 or 2009), indicating reproducibility of SC when the raw materials and the composting method are not changed. Differences in shoot height were not as pronounced as those for shoot DW. The results were encouraging, but further studies are still needed for producing compost with guaranteed suppressiveness properties.

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Optimal LED Wavelength Composition for the Production of High-Quality Watermelon and Interspecific Squash Seedlings Used for Grafting

Agronomy ◽

10.3390/agronomy9120870 ◽

2019 ◽

Vol 9 (12) ◽

pp. 870 ◽

Cited By ~ 1

Author(s):

Filippos Bantis ◽

Athanasios Koukounaras ◽

Anastasios S. Siomos ◽

Kalliopi Radoglou ◽

Christodoulos Dangitsis

Keyword(s):

Blue Emission ◽

Dry Weight ◽

Photosynthetic Photon Flux Density ◽

Stem Diameter ◽

Photon Flux ◽

Photon Flux Density ◽

Light Sources ◽

High Quality ◽

Light Emitting ◽

Shoot Dry Weight

Watermelon is cultivated worldwide and is mainly grafted onto interspecific squash rootstocks. Light-emitting diodes (LEDs) can be implemented as light sources during indoor production of both species and their spectral quality is of great importance. The objective of the present study was to determine the optimal emission of LEDs with wide wavelength for the production of watermelon and interspecific squash seedlings in a growth chamber. Conditions were set at 22/20 °C temperature (day/night), 16 h photoperiod, and 85 ± 5 μmol m−2 s−1 photosynthetic photon flux density. Illumination was provided by fluorescent (FL, T0) lamps or four LEDs (T1, T2, T3, and T4) emitting varying wide spectra. Watermelon seedlings had greater shoot length, stem diameter, cotyledon area, shoot dry weight-to-length (DW/L) ratio, and Dickson’s quality index (DQI) under T1 and T3, while leaf area and shoot dry weight (DW) had higher values under T1. Interspecific squash seedlings had greater stem diameter, and shoot and root DW under T1 and T3, while leaf and cotyledon areas were favored under T1. In both species, T0 showed inferior development. It could be concluded that a light source with high red emission, relatively low blue emission, and a red:far-red ratio of about 3 units seems ideal for the production of high-quality watermelon (scion) and interspecific squash (rootstock) seedlings.

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Pot-In-Pot Production and Cyclic Irrigation Influence Growth and Irrigation Efficiency of ‘Okame’ Cherries

Journal of Environmental Horticulture ◽

10.24266/0738-2898-16.3.159 ◽

1998 ◽

Vol 16 (3) ◽

pp. 159-162 ◽

Cited By ~ 1

Author(s):

John M. Ruter

Keyword(s):

Water Loss ◽

Production System ◽

Dry Weight ◽

Stem Diameter ◽

Total Biomass ◽

Root:Shoot Ratio ◽

Irrigation Application ◽

Application Efficiency ◽

Shoot Dry Weight ◽

Daily Water

Abstract A study was conducted with Prunus x incamp ‘Okame’ to evaluate the effects of a pot-in-pot production system (PIP) compared to a conventional above-ground system (CAG) and cyclic irrigation on plant growth and water loss. Plants were grown in #7 (26 liter) containers with a pinebark: sand (8:1 by vol) substrate. Cyclic irrigation provided the same total volume of water, but was applied one, three, or four times per day. Final plant height and stem diameter, shoot and root dry weight, total biomass, and root:shoot ratio all increased for plants grown pot-in-pot compared to above-ground. Multiple irrigation cycles increased stem diameter, shoot dry weight and total biomass compared to a single irrigation application. Multiple irrigation cycles also decreased the root:shoot ratio. Mean daily water loss (plant transpiration + evaporative loss from the substrate) was influenced by production system, irrigation, and date. Mean daily water loss was 30% higher for pot-in-pot grown plants compared to above-ground. Cyclic irrigation resulted in a two-fold decrease in average leachate volume and a 27% increase in overall irrigation application efficiency compared to a single application. Production system had no affect on leachate volume or irrigation application efficiency. Substrate pH increased when cyclic irrigation was used. Production system and irrigation had no affect on soluble salts. Nitrate-N concentrations were less in the leachate of plants grown pot-in-pot compared to above-ground.

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Pot-in-pot Production and Cyclic Irrigation Influences Growth and Evapotranspiration of `Okame' Cherry

HortScience ◽

10.21273/hortsci.32.3.546b ◽

1997 ◽

Vol 32 (3) ◽

pp. 546B-546 ◽

Cited By ~ 1

Author(s):

John M. Ruter

Keyword(s):

Plant Growth ◽

Production System ◽

Nitrate Nitrogen ◽

Dry Weight ◽

Stem Diameter ◽

Total Biomass ◽

Soluble Salts ◽

Root:Shoot Ratio ◽

Shoot Dry Weight ◽

Ground System

A study was conducted with Prunus × incamp `Okame' to evaluate the effects of a pot-in-pot production system compared to a conventional above-ground system and cyclic irrigation on plant growth and water loss. Plants were grown in #7 (26-L) containers with a 8:1 pinebark:sand (v/v) substrate. Cyclic irrigation provided the same total volume of water, but was applied one, three, or four times per day. Final plant height and stem diameter, shoot and root dry weight, total biomass, and root:shoot ratio were all increased for plants grown pot-in-pot compared to above-ground. Multiple irrigation cycles increased stem diameter, shoot dry weight, and total biomass, compared to a single irrigation application. Multiple irrigation cycles decreased the root:shoot ratio. Evapotranspiration was influenced by production system, irrigation, and date. Amount of water lost as leachate was influenced by irrigation and date. Cyclic irrigation resulted in a two-fold decrease in leachate volume. Soluble salts and nitrate-nitrogen in the leachate were influenced by an interaction between production system, irrigation, and date.

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Effect of Nitrogen, Gibberellic Acid, Triadimefon, and Kinetin on the Seedling Growth of Sapodilla (Achras sapota) and Tamarind (Tamarindus indica)

HortScience ◽

10.21273/hortsci.32.3.437c ◽

1997 ◽

Vol 32 (3) ◽

pp. 437C-437

Author(s):

J.P. Morales-Payan ◽

B.M. Santos

Keyword(s):

Gibberellic Acid ◽

Seedling Growth ◽

Dry Weight ◽

Internode Length ◽

Tamarindus Indica ◽

Loamy Soil ◽

Shoot Dry Weight ◽

Achras Sapota ◽

Nitrogen Rates ◽

Plastic Containers

Container experiments were conducted in the Dominican Republic to determine the effects of nitrogen, gibberellic acid, triadimefon, and kinetin on the seedling growth of sapodilla (Achras sapota) and tamarind (Tamarindus indica). Plants were started from seeds on cylindrical plastic containers (20 × 20 cm) filled with an artificial a 1:1 mixture of sand and loamy soil, allowing the growth of only one plant per container. Nitrogen rates (0.5, 0.75, and 1.0 g N per plant, applied as ammonium sulfate) were factorially combined with the rates (0, 25, 50, 75, and 100 ppm each) of the regulators. When the plants had three true leaves, nitrogen was applied to the growing mixture, whereas the growth regulators were applied foliarly. Plants were allowed to grow during 60 days after treatment. There were no nitrogen and regulator interactions. Kinetin treatments did not significantly influence shoot dry weight and height in either species. Both species responded with linearly increased height, internode length, and dry weight to increasing GA3 concentrations. Increasing rates of the growth retardant triadimefon significantly reduced the internode length and total height of sapodilla and tamarind seedlings. These results suggest that gibberellin and triadimefon could be effectively used as a means to stimulate or retard, respectively, the growth of sapodilla and tamarind.

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