Mechanism of Varietal Differences in Photosynthetic Rate of Soybean Leaves : III. Relationship between photosynthetic rate and some leaf-characters such as fresh weight, dry weight or mesophyll volume per unit leaf area

Light with a higher red to far-red ratio (R:FR) than sunlight reduces plant growth, but the cause has not been firmly established. In the present study, cucumber seedlings were grown under normal light (similar to sunlight; R:FR = 1.4) from metal-halide lamps or high-R:FR light (R:FR = 4.3) created by transmitting their light through FR-absorbing film, and then their growth parameters and photosynthesis were compared. The relative growth rate (RGR) at high R:FR was 92% of that under normal R:FR, although the net assimilation rate (NAR) did not differ between the treatments, indicating that changes in net photosynthesis per unit leaf area did not cause the growth inhibition at high R:FR. The CO2 exchange per unit leaf area did not differ between the treatments, which supports this hypothesis. The leaf area ratio (LAR) of total plant dry weight of high R:FR seedlings to that of normal R:FR seedlings was also 92%. This suggests that growth suppression in the high R:FR seedlings was caused mainly by decreased LAR. The specific leaf area (SLA) and leaf weight ratio (LWR), components of LAR, under high-R:FR light were 89% and 105%, respectively, of those under normal light, indicating that the smaller LAR at high R:FR mainly results from suppressed leaf enlargement per unit leaf dry matter.

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Relationship between visual colour rating and chlorophyll content, photosynthetic rate, and some growth characteristics in couchgrass (Cynodonspp. L.)

The Journal of Agricultural Science ◽

10.1017/s0021859600032639 ◽

1983 ◽

Vol 100 (1) ◽

pp. 221-225 ◽

Cited By ~ 1

Author(s):

M. S. Rahman

Keyword(s):

Leaf Area ◽

Chlorophyll Content ◽

Photosynthetic Rate ◽

Unit Area ◽

Dark Respiration ◽

Dry Weight ◽

Chlorophyll Contents ◽

Respiration Rates ◽

Unit Leaf ◽

Visual Colour

SUMMARYChlorophyll contents per unit leaf area and unit dry weight, chlorophylla:bratio, visual colour rating, specific leaf area, and leaf fresh weight: dry weight ratios were estimated for 12 couch (bermudagrass) varieties (Cynodonspp. L.) in winter (July) and spring (October). Net photosynthetic and dark respiration rates were estimated in winter only.The chlorophyll contents per unit leaf area were higher in all varieties in spring than in winter, but per unit weight were more variable. The varieties differed substantially in the net photosynthetic and dark respiration rates. The specific leaf areas were greater in winter than in spring in five varieties: in others it changed little. The fresh: dry weight ratios of the leaves were almost constant between varieties in the spring but varied greatly during the winter. Visual colour ratings were well correlated with chlorophyll contents per unit area but not with weight. The net photosynthetic rate was closely correlated with chlorophyll content (per unit area) but not so closely with colour rating.

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Comparative carbon dioxide exchange for two Populus clones grown in growth room, greenhouse, and field environments

Canadian Journal of Forest Research ◽

10.1139/x84-164 ◽

1984 ◽

Vol 14 (6) ◽

pp. 924-932 ◽

Cited By ~ 10

Author(s):

Neil D. Nelson ◽

Paul Ehlers

Keyword(s):

Net Photosynthetic Rate ◽

Leaf Area ◽

Photosynthetic Rate ◽

Photon Flux ◽

Photon Flux Density ◽

Growth Environment ◽

Photosynthetic Rates ◽

Unit Leaf Area ◽

Unit Leaf ◽

Growth Room

Light-saturated net photosynthetic rates per unit leaf area were 1.6–2.1 times greater for the photosynthetically mature leaves of plants of two hybrid Populus clones (NC-5260, 'Tristis No.1' (Populustristis Fisch. × P. balsamifera L.); NC-5326, 'eugenei' (P. deltoides Bartr. ex Marsh. × P. nigra L.)) grown in pots in the field than in comparable plants from a controlled environment growth room and a winter greenhouse. Stomatal resistances to CO2 in the field trees were only 0.4–0.6 of those in growth room and greenhouse trees. Mesophyll (residual) resistances to CO2 in field trees were 0.4–0.8 of those in growth room and greenhouse trees. Field plants had specific leaf weights 1.5–1.8 times higher than growth room and greenhouse plants, likely primarily owing to the greater average photosynthetic photon flux density in the field (835, 225, and 142 μE m−2 s−1 for field, growth room, and greenhouse conditions, respectively). When net photosynthetic rates (Ps) were corrected for the differences in specific leaf weights to derive net photosynthetic rate per unit leaf dry weight, the values were similar for plants from the three environments (Ps in field trees was 0.9–1.2 times Ps in growth room and greenhouse trees); gross photosynthetic rates per unit leaf weight were even more similar. Internal leaf CO2 concentrations, and photorespiration and dark respiration rates per unit leaf area were not related to growth environment. However, photorespiration rate as a percentage of net photosynthetic rate was lower in the field trees (12–16% in field trees, 19–24% in growth room trees, and 23–39% in greenhouse trees). Net photosynthetic rate was shown to be under strong genetic control in these clones. The effects of growth environment on variables of carbon exchange are sensitive to the basis of expression of those variables.

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Specific Leaf Weight and Nitrogen Allocation Responses to Light Exposure within Walnut Trees

HortScience ◽

10.21273/hortsci.26.2.183 ◽

1991 ◽

Vol 26 (2) ◽

pp. 183-185 ◽

Cited By ~ 12

Author(s):

I. Klein ◽

T.M. DeJong ◽

S.A. Weinbaum ◽

T.T. Muraoka

Keyword(s):

Leaf Area ◽

Light Exposure ◽

Juglans Regia ◽

Light Flux ◽

Dry Weight ◽

N Content ◽

Available N ◽

Unit Leaf Area ◽

Unit Leaf ◽

Highly Correlated

Exposure to photosynthetically active radiation and the consequent effect on leaf mass per unit leaf area (SLW) and nitrogen (percent dry weight and μg·mm-2) allocation within tree canopies was investigated in walnut (Juglans regia `Serr' and `Hartley') trees. Percent contribution of discrete light flux densities below light saturation (100-700 μmol·s-1·m-2) to the total light exposure of individual spurs, exposed up to 9 hour·day-1 to saturating light (>700 μmol·s-1·m-2), was minimal (<1 hour), indicating that individual spurs were either exposed or shaded most of the day. SLW and N content per unit leaf area of individual spurs were highly correlated (second-order polynomial curve fit) with light exposure within the tree canopy, indicating uneven allocation of available N for optimal utilization. Nitrogen expressed as percent dry weight was not correlated with light exposure and SLW. Leaf N content per leaf area was highly correlated (linear fit) with SLW.

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PETUNIA SEEDLING GROWTH - HPS PHOTOPERIOD STUDY

HortScience ◽

10.21273/hortsci.25.9.1103c ◽

1990 ◽

Vol 25 (9) ◽

pp. 1103c-1103

Author(s):

Will Healy ◽

David Graper

Keyword(s):

Soil Temperature ◽

Leaf Area ◽

Seedling Growth ◽

Photosynthetic Rate ◽

Dry Weight ◽

Fresh Weight ◽

Total Leaf Area ◽

Leaf Stage ◽

Exponential Increase ◽

Area Basis

Petunia `Red Flash' seedling were grown under HPS (175 μmolm-2 s-1) photoperiod treatments of 10, 12, 14 or 16 hr at 20C soil temperature in a shaded glasshouse where the maximum peak PPF was reduced to 150 μmolm-2s-1. Seedling dry weight and individual leaf area were determined daily. The photosynthetic rate was determined when seedlings reached the second true leaf stage.The dry weight response to increasing photoperiod durations was cubic with a peak at 14 hr. Seedling dry weight increased slowly during days 5 through 10 then increased rapidly during the next 7 to 10 days. This increase coincided with the unfolding of leaves one through four. The total leaf area showed a cubic response to the photoperiod treatments. The leaf area increased slowly then began an exponential increase after day 10. The photosynthetic rate per gram dry weight was increased by the 10 hr photoperiod treatment when compared to the 16 hr treatment. The increased photosynthetic rate was not observed when the data was calculated on a fresh weight or leaf area basis.

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Growth and Fruiting of Short-internode Main Dwarf, Normal-internode Parent, and Hybrid

HortScience ◽

10.21273/hortsci.25.10.1277 ◽

1990 ◽

Vol 25 (10) ◽

pp. 1277-1279 ◽

Cited By ~ 1

Author(s):

Dean E. Knavel ◽

Robert L. Houtz

Keyword(s):

Leaf Area ◽

Dry Weight ◽

Rubisco Activity ◽

Bisphosphate Carboxylase ◽

Unit Leaf Area ◽

Short Internode ◽

Unit Leaf ◽

Leaf Chlorophyll ◽

Ribulose 1 ◽

Total Dry Weight

Plants of Main Dwarf, a short-internode mutant of the normal-internode `Mainstream' muskmelon (Cucumis melo L.), have shorter internodes, fewer nodes, less total vine length, less total dry weight, smaller leaves, increased chlorophyll concentrations, increased specific leaf dry weight, and increased ribulose-1, 5-bisphosphate carboxylase/oxygenase (EC 4.1.1.39, rubisco) activity per unit leaf area than `Mainstream' plants. Main Dwarf plants produce an equal number of fruit as `Mainstream' plants but are only half their size. Many of the plant and fruit characteristics for F1(Main Dwarf × `Mainstream') are similar to those of `Mainstream', except for greater leaf chlorophyll and rubisco activity per unit leaf area. The F1 (`Mainstream' × Main Dwarf) produced fewer and lower weight fruit than its reciprocal, F1 (Main Dwarf × `Mainstream').

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Effect of Organic Manures on Growth, Rhizome Yield and Quality Attributes of Turmeric (Curcuma longa L.)

The Agriculturists ◽

10.3329/agric.v10i1.11060 ◽

2012 ◽

Vol 10 (1) ◽

pp. 16-22 ◽

Cited By ~ 2

Author(s):

M. Z. U. Kamal ◽

M. N. Yousuf

Keyword(s):

Leaf Area ◽

Dry Matter ◽

Curcuma Longa ◽

Dry Weight ◽

Fresh Weight ◽

Area Index ◽

Yield Attributes ◽

Organic Manures ◽

Neem Cake ◽

Yield And Quality

The investigation was carried out to evaluate the effect of different organic manures on turmeric with reference to vegetative growth, biomass production, rhizome yield and its attributes of turmeric (Curcuma longa L.). Turmeric showed better response to the application of organic manures. Plant with neem cake application had the taller plant (79.30 cm), maximum number of tillers per plant (5.40), leaf number (5.40), leaf area (44.09) leaf area index (0.429), fresh weight of halum ( 190.05g), fresh weight of root (49.13 g), fresh weight of rhizome per plant (256.21 g) and dry weight of halum (15.21g), dry weight of root (7.32 g), dry weight of rhizome per plant (40.35 g), total dry matter yield (6.85 t ha-1) than those received other types of manures. Moreover, yield attributes such as number of mother rhizomes per plant-1 (1.75), more number of primary rhizomes per plant-1 (5.19), secondary rhizomes per plant-1 (18.03) and tertiary rhizomes per plant (7.69) were also highly accelerated by neem cake application. Similarly, the same treatment expressed the best in terms of size of mother rhizome (7.69 cm), primary rhizome (21.86 cm) and secondary rhizomes (7.05 cm).All these parameters in cumulative contributed to produce the highest estimated fresh rhizomes yield & cured rhizomes yield (29.48 t ha-1, 5.59 t ha-1 respectively). The highest curing percentage (20.28) was observed in T3 treatment having mustard cake@ 2.0 t/ha. Thus, organic manure like neem cake was best fitted natural fertilizer for turmeric cultivation.DOI: http://dx.doi.org/10.3329/agric.v10i1.11060The Agriculturists 2012; 10(1): 16-22

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A method to improve leaf succulence quantification

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89131999000100002 ◽

1999 ◽

Vol 42 (1) ◽

Cited By ~ 33

Author(s):

André Mantovani

Keyword(s):

Leaf Area ◽

Weight Ratio ◽

Volume Ratio ◽

Dry Weight ◽

Fresh Weight ◽

Ecological Implications ◽

Leaf Succulence ◽

Sun Leaves

Leaf succulence has important physiological and ecological implications. Currently it is quantified by Delf's index (fresh weight/leaf area) and fresh weight/ dry weight ratio. Both indeces are reconsidered and a new index is proposed. Shade and sun leaves from terrestrial, hemiepiphytic and epiphytic aroids were studied. Delf's formula, which does not consider dry weight, overestimated leaf succulence. As fresh weight / dry weight ratio (fw / dw) does not consider leaf area, plants with the same fw / dw ratio were more than five times different in area. The last case was only possible with a decrease in surface / volume ratio and a increase of mesophyll thickness, components not measured by fw / dw ratio. The new index proposed here, which takes into consideration dry weight and leaf area, showed a high correlation to mesophyll thickness.

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PEMANFAATAN PUPUK ORGANIK CAIR PAITAN (Tithonia diversifolia) PADA BERBAGAI DOSIS DAN RAGAM APLIKASINYA TERHADAP PERTUMBUHAN KAILAN (Brassica oleracea Var. Acephala)

JURNAL AGROTEKNOLOGI ◽

10.24014/ja.v11i1.7802 ◽

2020 ◽

Vol 11 (1) ◽

pp. 25

Author(s):

AHMAD TAOFIK ◽

SOFIYA HASANI ◽

AYU CAHYANINGTYAS ◽

BUDY FRASETYA

Keyword(s):

Leaf Area ◽

Plant Height ◽

Analysis Of Variance ◽

Growth Parameters ◽

Organic Fertilizer ◽

Dry Weight ◽

Fresh Weight ◽

Application Method ◽

Randomized Design ◽

Two Factors

The paitan plant contains allelopathic compounds for other plants so that the utilize of paitan plant as a source of liquid organic fertilizer (LOF) has not been widely applied. This research aimed to study the interaction between LOF dosage and appropriate application method of LOF to increase the growth of kailan plants. The research conducted at experimental garden of UIN Bandung from June-August 2016. The experimental design was a completely randomized design with two factors and replicated four times. The first factor was application methods (A), i.e. a1=direct application to the soil, and a2= spraying. The second factor was LOF dosage (T), i.e. t0: 0 ml plant-1, t1: 20 ml plant-1, t2: 40 ml plant-1, t3: 60 ml plant-1, t4: 80 ml plant-1. The growth parameters observed i.e. plant height (14, 21, 28, 35 and 42 Day after Transplanting (DAT)), leaf area 42 DAT, plant dry weight 42 DAT, and plant fresh weight 42 DAT. The data then analyzed with analysis of variance at a significant level of 5%. If the analysis of variance was significant, the Duncan multiple range test was used at α=5%. The research results showed there was no interaction between method of application with a various dosage of paitan LOF to all of the growth parameters. The application paitan LOF showed similar growth in terms of plant height, leaf area, plant dry, and plant fresh weight. The application method of paitan LOF direct to the soil or spraying to leaves can not increase kailan plant growth.

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