PHOTOSELECTIVE SHADING COMPOUNDS REGULATE GROWTH OF HYPOESTES PHYLLOSTACHYA Bak.

`Pink Splash' Hyoestes were grown in chambers fitted with single-walled polycarbonate. Chambers were shaded with various photoselective shading compounds, using a white shading compound as a non-selective control. When grown under orange shading, plants had more shoot dry weight, greater leaf area, larger stem diameters, and were taller compared to plants shaded with white. When grown under green shading, plants had less shoot dry weight, less leaf area, smaller stem diameters, and were taller compared to plants shaded with white. Intermediate responses were recorded when plants were grown under red, blue or yellow shading. Differences in the ratio of red to far-red light among shading compounds did not provide a consistent explanation of growth responses.

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Growth and Photosynthetic Capacity of Basil Grown for Indoor Gardening under Constant or Increasing Daily Light Integrals

HortTechnology ◽

10.21273/horttech04442-19 ◽

2019 ◽

Vol 29 (6) ◽

pp. 880-888 ◽

Cited By ~ 1

Author(s):

Elisa Solis-Toapanta ◽

Celina Gómez

Keyword(s):

Leaf Area ◽

Photosynthetic Capacity ◽

Dry Weight ◽

Growth And Yield ◽

Growth Responses ◽

Light Saturation ◽

Saturation Point ◽

Shoot Dry Weight ◽

Light Saturation Point ◽

Over Time

In the quest to identify minimum daily light integrals (DLIs) that can sustain indoor gardening, we evaluated DLIs less than the recommended ranges for commercial production of basil (Ocimum basilicum). Experiments were conducted for 8 weeks to evaluate the effect of providing a constant vs. an increasing DLI over time (DLIInc) on growth and photosynthetic capacity of green (‘Genovese Compact’) and purple (‘Red Rubin’) basil grown hydroponically under a constant ambient temperature of 21 °C. Plants were grown under a 14 h·d–1 photoperiod and were subjected to the following DLI treatments: 4 (DLI4), 6 (DLI6), 8 (DLI8), or 10 (DLI10) mol·m–2·d‒1 (80, 119, 159, and 197 µmol·m‒2·s‒1, respectively); DLIInc was used as a fifth treatment and was achieved by transitioning hydroponic systems systematically to treatments with greater DLIs every 2 weeks. In general, regardless of cultivar, leaf area, leaf number, and overall growth [shoot fresh weight (SFW) and shoot dry weight (SDW)] were similar for plants grown under DLIInc to DLI4 and DLI6 during weeks 2, 4, and 6. However, plants grown under DLIInc produced the same leaf area as those grown under DLI10 at week 8. Nonetheless, across weeks, growth was significantly less under DLIInc compared with DLI10, but similar to that produced by DLI8 at week 8. Photosynthetic responses were significant only at week 8, for which leaves of plants grown under DLI8, DLI10, and DLIInc had 15% to 25% greater maximum gross carbon dioxide (CO2) assimilation (Amax) than plants grown under DLI4. The light saturation point of photosynthesis was unaffected by DLI, but showed a general increasing trend with greater DLIs. Overall, our results suggest that providing a constantly high DLI results in greater growth and yield than increasing the DLI over time. In addition, we found that changes in Amax and the light saturation point are not good indicators of the capacity of whole plants to make use of the available light for photosynthesis and growth. Instead, morphological and developmental traits regulated by DLI during the initial stages of production are most likely responsible for the growth responses measured in our study.

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Temperature Effects on Growth of Impatiens Plug Seedlings in Controlled Environments

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.117.2.209 ◽

1992 ◽

Vol 117 (2) ◽

pp. 209-215 ◽

Cited By ~ 3

Author(s):

David R. Dreesen ◽

Robert W. Langhans

Keyword(s):

Leaf Area ◽

Growth Period ◽

Dry Weight ◽

Photon Flux ◽

Initial Growth ◽

Growth Responses ◽

Shoot Height ◽

Seedling Age ◽

Shoot Dry Weight ◽

Air Temperatures

The objective of this study was to determine the dry weight, height, and leaf area growth responses of impatiens (Impatiens walerana Hook. f.) plug seedlings to air temperatures ranging from 18 to 29C. The conditions maintained in the controlled-environment growth rooms (CEGR) were ambient C02 levels, 24-h lighting, and photosynthetic photon flux (PPF) ranging from ≈215; to 335 μmol·m-2·s-1. Mean daily temperatures of the plug medium ranged from 19.6 to 27.7C. At the higher PPF level, shoot dry weight decreased at plug medium temperatures (PMT) > 25C; at lower PPF levels (<300 μmol·m-2·s-1), shoot dry weight continued to increase with PMT > 25C. The mean relative growth rate (MRGR) of shoot dry weight was positively correlated with PMT during the initial growth period (up to 14 days from sowing) and was negatively correlated thereafter. The maximum MRGR was predicted to occur at 11.7 days from sowing for a PMT of 19.6C, at 10.8 days for a PMT of 21.6C, and at 9.7 days for a PMT of 23.6C. Linear regression coefficients of shoot height as a function of PMT were substantially higher for seedlings grown at lower PPF than those for seedlings from the highest PPF level. Seedling leaf area consistently increased with increasing temperature. Net assimilation rate (NAR) decreased with increasing seedling age NAR increased with increasing PPF. A decrease in NAR was apparent at 29C relative to values at the lower temperatures. Leaf area ratio (LAR) declined with increasing seedling age and PPF; a quadratic relationship of LAR as a function of PMT indicates a minimum LAR at 22.5C. The seedlings grown at 29C were excessively tall, had thin succulent leaves, and were judged unacceptable for shipping and transplanting. Maximum quality indices (i.e., dry weight per height) were found at PMT of 24.3 to 25.OC for 10- to 14-day-old seedlings and at PMT of 23.0 to 24.OC for 16- to 20-day-old seedlings.

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EFFECT OF MINERAL DEFICIENCY ON MORPHOLOGICAL AND PHYSIOLOGICAL PARAMETERS AND ON SHOOT AND ROOT MINERAL PARTITIONING IN THREE SUNFLOWER VARIETIES / EFECTO DE LA FALTA DE ELEMENTOS MINERALAS SOBRE LOS PARAMENTROS MORFOLOGICOS Y FISIOLOGICOS Y REPARTICION DE ELEMENTOS MINERALES DE LA PARTE SOBRE EL SUELO Y DE LA RAIZ EN TRES VARIEDADES / INFLUENCE DE LA CARENCE D’ÉLÉMENTS MINÉRAUX SUR LES PARAMÈTRES MORPHOLOGIQUES ET PHYSIOLOGIQUES ET SUR LA DISTRIBUTION DES ÉLÉMENTS MINÉRAUX ENTRE LA PARTIE AÉRIENNE ET LA RACINE POUR TROIS SORTES DE TOURNESOL

Helia ◽

10.1515/helia.2001.24.35.135 ◽

2001 ◽

Vol 24 (35) ◽

pp. 135-148

Author(s):

Mohammed El Midaoui ◽

Ahmed Talouizte ◽

Benbella Mohamed ◽

Serieys Hervé ◽

Ait Houssa Abdelhadi ◽

...

Keyword(s):

Leaf Area ◽

Dry Matter ◽

Growth Parameters ◽

Dry Weight ◽

Mineral Deficiency ◽

P Deficiency ◽

Plant Parts ◽

Shoot Dry Weight ◽

K Deficiency ◽

Matter Effect

SUMMARYAn experiment has been carried out in order to study the behaviour under mineral deficiency of three sunflower genotypes, a population variety (Oro 9) and two hybrids (Mirasol and Albena). Sunflower seedlings were submitted to five treatments: N deficiency (N0), P deficiency (P0), K deficiency (K0), N and K deficiency (N0K0) and a control. Plants were harvested when they reached 3-4 true pairs of leaves. Growth parameters measured (height, total leaf area, root length, root and shoot dry mater) were all significantly reduced by mineral deficiency. Leaf area was most reduced by N0 (-61%) and P0 (-56%). Total dry matter was most affected by N0 (-63%) and by N0K0 (-66%). Genotype comparisons showed that Oro 9 had the highest shoot dry matter while Albena had the lowest root dry matter. Effect of mineral deficiency on content and partitioning of N, P, K, Ca and Na was significant and varied according to treatments and among plant parts. Shoot dry weight was significantly correlated with root N content (r2=0.81) and root K content (r2=-0.61) for N0 and K0.

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Effect of nitrogen fertilizer on growth and yield of semi-dwarf and tall varieties of winter wheat

The Journal of Agricultural Science ◽

10.1017/s0021859600056604 ◽

1978 ◽

Vol 91 (1) ◽

pp. 31-45 ◽

Cited By ~ 39

Author(s):

I. Pearman ◽

S. M. Thomas ◽

G. N. Thorne

Keyword(s):

Winter Wheat ◽

Grain Yield ◽

Leaf Area ◽

Dry Weight ◽

The Other ◽

Growth And Yield ◽

Shoot Dry Weight ◽

Phosphorus And Potassium ◽

Main Effects ◽

Dwarf Variety

SummaryEight amounts of nitrogen ranging from 0 to 210 kg N/ha were applied to two tall and one semi-dwarf variety of winter wheat in the spring of 1975 and 1976. The tall varieties were Cappelle-Desprez and Maris Huntsman; the semi-dwarf variety was Maris Fundin in 1975 and Hobbit in 1976. Interactions between varieties and nitrogen were few and small compared with the main effects. All varieties produced their maximum grain yields with 180 kg N/ha. The yield of the semi-dwarf varieties, but not the others, decreased slightly with more nitrogen.Cappelle-Desprez yielded less grain than the other varieties in both years. In 1975 the yields of Maris Fundin and Maris Huntsman were similar and in 1976 Hobbit yielded more than Maris Huntsman. The varieties had similar numbers of ears at maturity and similar patterns of tillering. The semi-dwarf varieties had most grains per spikelet, and hence grains per ear, and Cappelle-Desprez had least. The semi-dwarf varieties had the smallest grains. The semi-dwarf varieties had less straw than the other varieties and hence the largest ratios of grain to total above-ground dry weight. The decrease in dry weight of stem and leaves between anthesis and maturity was similar for all varieties. In 1975 the efficiency of the top two leaves plus top internode in producing grain was the same for all varieties, but in 1976 Hobbit was more efficient than the other two. There were some small differences between varieties in nutrient uptake that were not related to differences in growth. Maris Fundin tended to have a greater phosphorus and potassium content than the tall varieties. Hobbit contained slightly less nitrogen than the tall varieties at maturity, and had a smaller concentration of nitrogen in the grain.Applying 210 kg N/ha doubled grain yield in 1975. Applying nitrogen resulted in a largeincrease in number of ears and a small increase in number of grains per ear due to the development of more fertile spikelets per ear. Nitrogen decreased dry weight per grain, especially of the semi-dwarf varieties. With extra nitrogen, straw dry weight at maturity, shoot dry weight atanthesis and leaf area were all increased relatively more than grain yield, and stems lost moredry weight between anthesis and maturity than without nitrogen. The year 1976 was exceptionallydry and nitrogen had only small effects in that it affected neither straw dry weight nor numberof ears but slightly increased grain yield by increasing the number of spikelets and number of grains per spikelet. It also increased leaf area proportionately to grain yield. In 1975 nitrogen increased evaporation of water from the crop before anthesis but decreased it after anthesis, even though it continued to increase the extraction of water from below 90 cm.

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Exogenous Antioxidants Enhance Seedling Growth and Yield of Artificially Aged Cabbage and Lettuce Seeds

Horticulturae ◽

10.3390/horticulturae7090274 ◽

2021 ◽

Vol 7 (9) ◽

pp. 274

Author(s):

Ademola Adetunji ◽

Sershen ◽

Boby Varghese ◽

Norman Pammenter

Keyword(s):

Leaf Area ◽

Seedling Growth ◽

Seedling Emergence ◽

Dry Weight ◽

Growth And Yield ◽

Seed Vigour ◽

Beneficial Effects ◽

Shoot Dry Weight ◽

Antioxidant Defence System ◽

Aged Seeds

Aged seeds exhibit compromised vigour in terms of germination, seedling emergence and growth, but this can to some extent be alleviated by invigoration treatments before sowing. This study aimed to investigate ageing rates and patterns in cabbage (Brassica oleraceae) and lettuce (Lactuca sativa) seeds and whether the beneficial effects of invigorating aged seeds with exogenous antioxidants translate to enhanced seedling performance. Seeds were artificially aged to 25% viability before soaking in 0.4 mM glycerol, 0.6 mM GSH and 0.2 mM trolox for cabbage, and 0.6 mM glycerol, GSH and trolox for lettuce; deionised water served as a control. After 14 days of sowing, seedling emergence percentage, mean emergence time, mean daily emergence, and time taken to 25% emergence were computed. Seedling vigour index, root and shoot dry weight, root:shoot ratio, leaf area, leaf area ratio, and leaf chlorophyll content were assessed 6 weeks after sowing. Furthermore, the photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (E), and chlorophyll fluorescence were measured 6 weeks after sowing. Notably, ageing resulted in the loss of seed vigour and viability at higher rates in lettuce than cabbage. Seed pretreatment with glycerol promoted seedling growth in both species and shoot dry weight in lettuce, while glycerol and GSH enhanced Pn, Gs and E in lettuce. Trolox also enhanced Pn and E in lettuce. The beneficial effects of the antioxidant treatments are thought to be associated with the protection of photosystems from oxidative stress and/or stimulation of enzymes involved in photosynthesis, possibly through an enhanced antioxidant defence system during the early development stages when seedlings are particularly vulnerable to stress.

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Whole-plant Response of Six Poinsettia Cultivars to Three Fertilizer and Two Irrigation Regimes

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.121.1.69 ◽

1996 ◽

Vol 121 (1) ◽

pp. 69-76 ◽

Cited By ~ 2

Author(s):

Ursula Schuch ◽

Richard A. Redak ◽

James Bethke

Keyword(s):

Leaf Area ◽

Chlorophyll Content ◽

Dry Weight ◽

Shoot Biomass ◽

Vegetative Development ◽

Chlorophyll Contents ◽

Shoot Dry Weight ◽

Irrigation Regimes ◽

Whole Plant ◽

Leaf N

Six cultivars of poinsettia (Euphorbia pulcherrima Wind.), `Angelika White', `Celebrate 2', `Freedom Red', `Lilo Red', `Red Sails', and `Supjibi Red' were grown for 9 weeks during vegetative development under three constant-feed fertilizer treatments, 80,160, or 240 mg N/liter and two irrigation regimes, well-watered (high irrigation) or water deficient (low irrigation). Plants fertilized with 80 or 240 mg N/liter were 10% to 18% shorter, while those fertilized with 160 mg N/liter were 25 % shorter with low versus high irrigation. Leaf area and leaf dry weight increased linearly in response to increasing fertilizer concentrations. Low irrigation reduced leaf area, leaf, stem, and shoot dry weight 3670 to 41%. Cultivars responded similarly to irrigation and fertilizer treatments in all components of shoot biomass production and no interactions between the main effects and cultivars occurred. Stomatal conductance and transpiration decreased with increasing fertilizer rates or sometimes with low irrigation. Highest chlorophyll contents occurred in leaves of `Lilo Red' and `Freedom Red'. Leaves of plants fertilized with 80 mg N/liter were deficient in leaf N and had 40 % to 49 % lower leaf chlorophyll content compared to plants fertilized with 160 or 240 mg N/liter. Irrigation had no effect on leaf N or chlorophyll content. At the end of the experiment leaves of `Supjibi Red' and `Angelika White' contained higher concentrations of soluble proteins than the other four cultivars.

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The effect of barley yellow dwarf virus on early plant growth in ryegrass (Lolium spp.)

Australian Journal of Agricultural Research ◽

10.1071/ar9890293 ◽

1989 ◽

Vol 40 (2) ◽

pp. 293 ◽

Cited By ~ 6

Author(s):

DR Eagling ◽

RJ Sward ◽

GM Halloran

Keyword(s):

Leaf Area ◽

Growth Rates ◽

Barley Yellow Dwarf Virus ◽

Dry Weight ◽

Relative Growth ◽

Relative Growth Rates ◽

Root Dry Weight ◽

Shoot Dry Weight ◽

Barley Yellow Dwarf ◽

Yellow Dwarf Virus

Measurements were made on the effect of barley yellow dwarf virus (BYDV) infection on the early growth of four commercial cultivars of ryegrass (Lolium spp.) under two different temperatures (24�C and 16�C). At 24'C, BYDV infection was associated with reduced root dry weight (30-40%) in all cultivars; the effect of infection on shoot dry weight and leaf area was variable. At 16�C, the effect of BYDV infection was variable, being associated with increases in root dry weight, shoot dry weight, and leaf area in one cultivar (Grasslands Ariki) and decreases in another (Victorian). In two other cultivars, root dry weight, shoot dry weight and leaf area were not significantly affected (P>0.05) by infection with BYDV.At 24�C, the reductions in root dry weight associated with BYDV infection were not concomitant with reductions in the root relative growth rates. Up to at least 28 days after inoculation (46-50 days after germination) reductions in root dry weight were associated with both aphid-feeding damage and virus infection. Experiments with the cultivar Victorian, showed that shoot dry weight was not significantly affected (P>0.05) by feeding with viruliferous (BYDV) or non-viruliferous aphids (Rhopalosiphum padi L.). At 16�C, changes in root and shoot dry weight were associated with changes in the root and shoot relative growth rates.

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Effects of CGA-43089 on Responses of Sorghum (Sorghum Bicolor) to Metolachlor Combined by Ozone or Antioxidants

Weed Science ◽

10.1017/s0043174500068983 ◽

1983 ◽

Vol 31 (2) ◽

pp. 280-284 ◽

Cited By ~ 25

Author(s):

Kriton K. Hatzios

Keyword(s):

Sorghum Bicolor ◽

Propyl Gallate ◽

Dry Weight ◽

Air Pollutant ◽

Additive Effect ◽

Piperonyl Butoxide ◽

Interactive Effects ◽

Growth Responses ◽

Shoot Dry Weight ◽

Combination Treatments

In greenhouse studies, the potential interactive effects of metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] treatments combined with the air pollutant ozone (O3) or the antioxidants, piperonyl butoxide {α-[2-butoxyethyl) ethoxy]-4,5-dimethylenedioxy-2-propyltoluene} andn-propyl gallate, on the growth of sorghum [Sorghum bicolor(L.) Moench ‘Funk G522DR’] seedlings that were protected or unprotected with the antidote, CGA-43089 [α-(cyanomethoximino)-benzacetonitrile], were examined. Metolachlor was applied preplant incorporated at rates of 2.2, 3.9, and 5.6 kg/ha, and it was evaluated against fumigation with O3at 0.2 and 0.3 ppmv or against 4.9, 6.7, and 9.0 kg/ha of each antioxidant applied preplant incorporated. In combination treatments, shoot dry weight at 30 days after planting was reduced more than expected by metolachlor in the presence of the protectant CGA-43089 and ozone or some rates of the two antioxidants, suggesting synergism. In the absence of the protectant, CGA-43089, growth responses of sorghum to combination treatments of metolachlor with ozone or propyl gallate suggested an additive effect, although some treatments of metolachlor combined with piperonyl butoxide interacted synergistically.

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Herbicide Effects on Parasitism of Tomato by Hemp Broomrape

Weed Science ◽

10.1017/s0043174500032252 ◽

1973 ◽

Vol 21 (3) ◽

pp. 253-258 ◽

Cited By ~ 7

Author(s):

A. R. Saghir ◽

C. L. Foy ◽

K. M. Hameed

Keyword(s):

Lycopersicon Esculentum ◽

Activated Charcoal ◽

Dry Weight ◽

Shoot Dry Weight ◽

Crop Injury ◽

Selective Control ◽

Tomato Roots ◽

Orobanche Ramosa ◽

Herbicide Effects

Thirteen soil-incorporated herbicides, mainly of the dinitroaniline and carbamate groups, were evaluated in the greenhouse for selective control of hemp broomrape (Orobanche ramosaL.) in tomato (Lycopersicon esculentumMill. ‘Rutgers’). Hemp broomrape readily parasitized tomato roots and competed vigorously with the host. Shoots of the parasite emerged within 6 weeks after inoculation. Herbicides at 0.1 to 10.0 ppmw, with one exception, significantly reduced shoot dry weight of tomato measured at 10 weeks after treatment, in comparison with untreated, noninoculated controls. Generally, the degree of inhibition of establishment of the parasite was correlated with herbicidal injury to tomato. None of the treatments prevented the establishment of the parasite without causing severe crop injury. However,N-n-propyl-N-tetrahydrofurfuryl-4-trifluoromethyl-2,6-dinitroaniline (CGA-14397, ER-9063) at 3.3 and 6.6 ppmw exhibited some degree of selectivity as indicated by relative shoot dry weights of the host and parasite. Activated charcoal applied as a root dip on tomato or in soil admixtures prior to transplanting had no effect on parasitism and growth of hemp broomrape.

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Dog mustard (Erucastrum gallicum) response to crop competition

Weed Science ◽

10.1017/s0043174500093048 ◽

1997 ◽

Vol 45 (3) ◽

pp. 397-403

Author(s):

David A. Wall

Keyword(s):

Interspecific Competition ◽

Leaf Area ◽

Seed Production ◽

Growth And Development ◽

Dry Weight ◽

Field Studies ◽

Limiting Factor ◽

Shoot Dry Weight ◽

Summer Fallow ◽

Crop Competition

Greenhouse studies suggested that dog mustard was less competitive than wheat, but of similar competitiveness to flax. In field studies, dog mustard growth and development were markedly affected by crop competition. Competition from flax and wheat reduced dog mustard leaf area, shoot dry weight, plant height, and seed production compared with the weed grown on summer-fallow. Dog mustard was a prolific seed producer when grown in the absence of interspecific competition. On summer-fallow, dog mustard produced as many as 79,100 seeds plant−1when moisture was not a limiting factor. However, average seed production was 19,400 and 8000 seeds plant−1in 1994 and 1995, respectively.

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