Growth Responses of Dactylis glomerata, Lolium perenne and Phalaris aquatica to Chronic Ozone Exposure

1980 ◽  
Vol 7 (5) ◽  
pp. 511 ◽  
Author(s):  
DC Horsman ◽  
AO Nicholls ◽  
DM Calder
Keyword(s):  
Leaf Area ◽  
Dactylis Glomerata ◽  
Dry Weight ◽  
Ozone Exposure ◽  
Growth Responses ◽  
Relative Growth ◽  
Leaf Chlorosis ◽  
The Difference ◽  
Net Assimilation ◽  
Total Dry Weight

D. glomerata, L. perenne and P. aquatica were exposed to 9 parts per hundred million ozone for 4 h per day on 5 days per week for 5 weeks. The grasses responded similarly and significant changes in growth were generally observed only at the end of the exposure. The changes in growth were accompanied by slight leaf chlorosis. Total dry weight and yield (above-ground dry weight) were significantly reduced (14-21%) by the treatment. Root growth was impaired the most, followed by stem and then leaves. Specific leaf area was generally lower in ozone-treated plants but the difference was not significant. Effects on relative growth rate were mainly due to the decrease in net assimilation rate, leaf area ratio remaining relatively unchanged.

Shading Effects on Growth and Partitioning of Plant Biomass in Cogongrass (Imperata cylindrica) from Shaded and Exposed Habitats

Weed Science ◽  
1980 ◽  
Vol 28 (6) ◽  
pp. 735-740 ◽  
Author(s):  
D. T. Patterson
Keyword(s):  
Leaf Area ◽  
Plant Biomass ◽  
Dry Weight ◽  
Imperata Cylindrica ◽  
Leaf Biomass ◽  
Growth Responses ◽  
Net Assimilation ◽  
Total Dry Weight ◽  
Sun And Shade ◽  
Shading Effects

The growth responses of cogongrass [Imperata cylindrica(L.) Beauv.] were studied in a controlled-environment greenhouse with a day/night temperature of 29/23 C, under full available light and 56 and 11% of full light. The cogongrass plants were grown from stem and rhizome propagules originating from an interstate highway median, a pecan [Carya illinoensis(Wangenh.) K. Koch] plantation, and a pine (Pinusspp.) forest. After 89 days, the plants from all three populations produced, on average, three times as much total dry weight and leaf area in full available sunlight as in 56% full light and 20 times as much as in 11% full light. The distribution of plant biomass into rhizomes decreased with shading, whereas the distribution into leaves increased. The distribution of leaf biomass as leaf area also increased with shading, with the result that the plants grown in 11% full light had leaf area ratios about 2.5 times greater than those grown in full light. Reductions in dry matter production with shading were due to significant reductions in both net assimilation rate and leaf area duration or total amount of leaf area present. The plants from the shaded and exposed habitats generally did not differ significantly in their responses to shading. Thus, there is little evidence for the presence of sun and shade ecotypes in the populations of cogongrass studied.

Effects of Chronic Ozone Exposure on the Growth of Trifolium subterraneum and Trifolium repens

1981 ◽  
Vol 8 (5) ◽  
pp. 405 ◽  
Author(s):  
DC Horsman ◽  
AO Nicholls ◽  
DM Calder
Keyword(s):  
Trifolium Subterraneum ◽  
Dry Weight ◽  
Plant Part ◽  
Ozone Exposure ◽  
Rapid Decline ◽  
Relative Growth ◽  
Area 6 ◽  
Leaf Necrosis ◽  
Net Assimilation ◽  
Total Dry Weight

Plants of Trifolium subterraneum and T. repens were exposed to 9 parts per hundred million ozone for 4 h per day, 5 days per week for 5 weeks. Leaf necrosis was apparent after the first week of exposure and this was followed by the death of some leaves and stems. At the end of the exposure, significant reductions were found in total dry weight (30-40%), plant part dry weight and leaf area (ͭ6 30%). Ozone caused a rapid decline in relative growth rate which was related to a reduction in net assimilation rate.

A study of growth in swards of timothy and meadow fescue. I. Uninterrupted growth

1958 ◽  
Vol 51 (3) ◽  
pp. 347-352 ◽  
Author(s):  
R. H. M. Langer
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Leaf Size ◽  
Dry Weight ◽  
Meadow Fescue ◽  
Area Index ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Number Of Leaves ◽  
Total Dry Weight

1. Swards of S. 48 timothy and S. 215 meadow fescue growing alone or together were sampled at intervals of 3 weeks throughout the season. The number and weight of leaves, stems and ears were determined, and leaf area was estimated.2. Despite high rainfall, the total number of tillers in both species declined from the beginning of the experiment until early July, but increased again from then onwards until the original complement had been approximately restored. The number of leaves failed to show a corresponding increase in the autumn because each tiller carried fewer leaves than earlier in the year.3. In the spring total dry weight increased more rapidly in meadow fescue than in timothy which in turn out-yielded meadow fescue later in the season. Both species attained their greatest dry weight soon after ear emergence, a period which was marked by considerable crop growth and relative growth rates.4. Leaf area index reached a maximum before total dry weight had increased to its highest level, but then declined in both species. Meadow fescue differed from timothy by producing a second crop of foliage after the summer with a leaf area index of about 7. This second rise appeared to be due mainly to increased leaf size in contrast to timothy whose leaves became progressively smaller towards the end of the season.5. The differences in growth between the species discussed with reference to their dates of ear emergence which in this experiment differed by about 6 weeks.

Phenyl indole-3-thiolobutyrate increases growth of transplanted 1-0 red oak

1988 ◽  
Vol 18 (1) ◽  
pp. 131-134
Author(s):  
Daniel K. Struve ◽  
W. Timothy Rhodus
Keyword(s):  
Leaf Area ◽  
Butyric Acid ◽  
Dry Weight ◽  
Area Ratio ◽  
Leaf Area Ratio ◽  
Red Oak ◽  
Relative Growth ◽  
Auxin Treatment ◽  
Net Assimilation

The basal 1 cm of taproot of dormant bareroot 1-0 red oak (Quercusrubra L.) seedlings were given a 3-s dip in 20, 40, or 80 mM concentrations of indole-3-butyric acid (IBA), phenyl indole-3-thiolobutyrate (P-ITB), or equal parts IBA and P-ITB at 20 or 40 mM concentrations. Sixty control seedlings were dipped in 95% ethanol, while 30 seedlings were used for each auxin treatment. Seedlings were potted on May 12, 1986, and grown outdoors. At the end of the 104-day study period, all concentrations of IBA and P-ITB significantly increased number of roots regenerated (from 5.3 with 20 mM IBA to 11.9 for 80 mM IBA) compared with control seedlings. However, P-ITB-treated seedlings produced significantly more leaves (20–24) and leaf area (320–472 cm2), and up to 10 g more dry weight than IBA and non-auxin-treated seedlings. P-ITB treated seedlings had higher relative growth and net assimilation rates and lower leaf area ratio than IBA-treated or control seedlings. Seedlings treated with 20 mM of equal parts IBA and P-ITB were similar to P-ITB-treated seedlings while seedlings treated with the 40 mM IBA and P-ITB combination were similar to IBA-treated seedlings.

scholarly journals Fitness Cost of Imazamox Resistance in Wild Poinsettia (Euphorbia heterophylla L.)

Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1859
Author(s):  
Saeid Hassanpour-bourkheili ◽  
Mahtab Heravi ◽  
Javid Gherekhloo ◽  
Ricardo Alcántara-de la Cruz ◽  
Rafael De Prado
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Specific Leaf Area ◽  
Dry Weight ◽  
Area Ratio ◽  
Fitness Cost ◽  
Seed Plant ◽  
Growth Indices ◽  
Relative Growth ◽  
Net Assimilation

Wild poinsettia (Euphorbia heterophylla L.) is a difficult-to-control weed in soybean production in Brazil that has developed resistance to herbicides, including acetolactate synthase inhibitors. We investigated the potential fitness cost associated to the Ser-653-Asn mutation that confers imazamox resistance in this weed. Plant height, leaf and stem dry weight, leaf area and seed production per plant as well as the growth indices of specific leaf area, leaf area ratio, relative growth rate and net assimilation in F2 homozygous resistant (R) and susceptible (S) wild poinsettia progenies were pairwise compared. S plants were superior in most of the traits studied. Plant heights for S and R biotypes, recorded at 95 days after planting (DAP), were 137 and 120 cm, respectively. Leaf areas were 742 and 1048 cm2 in the R and S biotypes, respectively. The dry weights of leaves and stems in the S plants were 30 and 35%, respectively, higher than in the R plants. In both biotypes, the leaves had a greater share in dry weight at early development stages, but from 50 DAP, the stem became the main contributor to the dry weight of the shoots. The R biotype produced 110 ± 4 seed plant−1, i.e., 12 ± 3% less seeds per plant than that of the S one (125 ± 7 seed plant−1). The growth indices leaf area ratio and specific leaf area were generally higher in the S biotype or similar between both biotypes; while the relative growth rate and net assimilation rate were punctually superior in the R biotype. These results demonstrate that the Ser-653-Asn mutation imposed a fitness cost in imazamox R wild poinsettia.

Gibberellic acid induced growth acceleration in Populus hybrids

1984 ◽  
Vol 14 (6) ◽  
pp. 850-854 ◽  
Author(s):  
S. B. Rood ◽  
G. Daicos ◽  
T. J. Blake
Keyword(s):  
Gibberellic Acid ◽  
Leaf Area ◽  
Foliar Spray ◽  
Dry Weight ◽  
Height Growth ◽  
Total Leaf Area ◽  
Leaf Production ◽  
Relative Growth ◽  
Shoot Dry Weight ◽  
Net Assimilation

Weekly applications of 0.4 mg gibberellic acid (GA) in 8 μL 95% ethanol micropipetted onto shoots of rooted cuttings increased Populuseuramericana (Dode) Guinier height growth by 54% and shoot dry weight by 25% after 21 days. Total leaf area increased by 21% as a result of more rapid leaf production and slightly larger leaf sizes. Root growth was unaffected by GA treatment. The observed GA-induced acceleration resulted from an increase in relative growth rate while mean net assimilation rate was unaffected. Owing to a substantial increase in the number and size of leaves, the leaf area ratio, representing the ratio of photosynthesizing to respiring material, increased. While direct micropipette application of GA promoted height growth and primary shoot dry weight accumulation, GA application through either foliar spray or soil drench also promoted the growth of secondary shoots. Application of GA to shoots was more effective in promoting shoot growth than application through the roots. Direct GA application also promoted the growth of P. alba L. × P. grandidentata Michx. and P. × canescens (Ait.) Smith × P. alba × P. grandidentata. Thus, GA can be used for hastening early growth of these trees under winter greenhouse conditions.

EFFECT OF DAYLENGTH ON THE GROWTH OF WHEAT

1967 ◽  
Vol 45 (1) ◽  
pp. 117-131 ◽  
Author(s):  
D. J. C. Friend ◽  
V. A. Helson ◽  
J. E. Fisher
Keyword(s):  
Leaf Area ◽  
Dry Weight ◽  
Area Ratio ◽  
Leaf Area Ratio ◽  
Relative Growth ◽  
Stages Of Growth ◽  
Total Plant ◽  
Number Of Leaves ◽  
Net Assimilation ◽  
Daily Total

Leaf area per plant, total number of leaves and tillers, and total plant dry weight increased with increasing daylength over the range 8 to 24 h. The increase in the net assimilation rate and relative growth rate with increasing daily total radiation was similar to that obtained by raising the intensity of light given to plants grown under continuous illumination.During the vegetative phase of growth, the leaf area ratio decreased with increasing daylength, mostly because of an increased leaf thickness, again dependent on the level of total daily radiation. During the later stages of growth, earlier floral initiation at long daylengths caused an early decline in the leaf area ratio because of the rapid growth of the stem associated with inflorescence formation. This was a photoperiodic effect independent of the level of total daily radiation, as shown by supplementing an 8-h daylength with 8 h of low-intensity illumination.

Temperature Effects on Growth and Leaf Production in Three Weed Species

Weed Science ◽  
1984 ◽  
Vol 32 (5) ◽  
pp. 655-663 ◽  
Author(s):  
Elizabeth P. Flint ◽  
David T. Patterson ◽  
David A. Mortensen ◽  
George H. Riechers ◽  
Jan L. Beyers
Keyword(s):  
Leaf Area ◽  
Leaf Size ◽  
Dry Weight ◽  
Weed Species ◽  
Leaf Production ◽  
Sesbania Exaltata ◽  
Axillary Branch ◽  
Hemp Sesbania ◽  
Net Assimilation ◽  
Total Dry Weight

Sicklepod (Cassia obtusifoliaL. ♯6CASOB), hemp sesbania [Sesbania exaltata(Raf.) Cory ♯ SEBEX], and showy crotalaria (Crotalaria spectabilisRoth. ♯ CVTSP) were grown in controlled-environment greenhouses with day/night temperatures of 23/17, 26/20, 29/23, and 32/26 C. Plant height, leaf area, and total dry weight at 53 days after planting increased significantly with temperatures between 23/17 and 29/23 C in sicklepod and showy crotalaria, and between 23/17 and 32/26 C in hemp sesbania. In all species, leaves were produced more rapidly as temperature increased. Axillary branch leaf production was greatest at 29/23 C in sicklepod, and at 29/23 and 26/20 C in showy crotalaria; hemp sesbania showed little axillary branch development. Total dry-matter production in all species was closely correlated with leaf area duration, but not with net assimilation rate. Differences in total main stem leaf area in all species were primarily due to differences in leaf number rather than to differences in leaf size at maturity.

scholarly journals Growth analysis in chard plants (Beta vulgaris L. Cicla, cv. 'Pencas Blancas') exposed to different light quality

2014 ◽  
Vol 32 (2) ◽  
pp. 205-212 ◽  
Author(s):  
Fánor Casierra-Posada ◽  
Esteban Zapata-Casierra ◽  
Daniel A. Chaparro-Chaparro
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Dry Matter ◽  
Light Quality ◽  
Dry Weight ◽  
Dry Mass ◽  
Dry Matter Partitioning ◽  
Absolute Growth ◽  
Net Assimilation ◽  
Total Dry Weight

To determine the effects of light quality on the growth indices of plants, Pencas Blancas cultivar chard plantlets were grown for 2 months under five different light treatments, obtained by filtering sunlight through colored polyethylene films. The treatments included: red, blue, green, yellow and transparent cover colors. A transparent cover (white light) was used as the control. The colored covers affected the plant growth. The plants grown under the yellow cover presented a better behavior with regards to growth, taken as: total dry weight per plant, leaf area, specific leaf area, absolute growth rate, relative growth rate, harvestable dry matter and root to shoot ratio. The dry matter partitioning in the leaves and roots was affected by the light quality, but not in the petioles, with a higher accumulation of dry mass in the leaves of plants grown under the yellow cover. As a consequence of the enhanced leaf area in the plants under the yellow cover, they also had the highest water uptake. On the other hand, the highest net assimilation rate value was found in plants grown under the transparent cover. These results open up the possibility of using yellow colored cover in leafy green vegetables, especially in chard plants grown under controlled conditions.

scholarly journals Influence of Rootstock, Scion, and Water Deficits on Growth of `Colt' and `Meteor' Cherry Trees

HortScience ◽  
1991 ◽  
Vol 26 (9) ◽  
pp. 1204-1207 ◽  
Author(s):  
Thomas G. Ranney ◽  
Nina L. Bassuk ◽  
Thomas H. Whitlow
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Prunus Avium ◽  
Dry Weight ◽  
Root Surface ◽  
Prunus Cerasus ◽  
Root Surface Area ◽  
Assimilation Rate ◽  
Relative Growth ◽  
Net Assimilation

Growth and physiological characteristics were evaluated in autografted and reciprocally grafted plants of Prunus avium L. ×pseudocerasus Lindl. `Colt' and Prunus cerasus L. `Meteor'. Containerized plants were grown for 150 days in a greenhouse under either well-watered or water-stressed conditions. Both the scion and rootstock influenced growth (relative growth rate, R̄), morphological [leaf area : root surface area (LARSA) and specific leaf area (SLA)], and physiological (mean net assimilation rate, Ē) characteristics of grafted plants. Regardless of the watering regime, plants with `Meteor' scions and `Colt' rootstocks maintained higher R̄ than plants with `Colt' scions and `Meteor' rootstocks. This enhanced growth occurred as a result of higher Ē. Measurements on water-stressed plants also showed that the graft combination of `Meteor' on `Colt' had the lowest LARSA, while the reciprocal combination of `Colt' on `Meteor' had the highest. Differences in LARSA among water-stressed plants primarily reflected changes in SLA, as influenced by both rootstock and scion, and not in partitioning of dry weight between these organs.

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