Effects of nitrogen fertilization on leaf area, light interception, and productivity of short-rotation Populustrichocarpa × Populusdeltoides hybrids

1994 ◽  
Vol 24 (1) ◽  
pp. 166-173 ◽  
Author(s):  
Paul E. Heilman ◽  
Xie Fu-Guang
Keyword(s):  
Leaf Area ◽  
Carbon Allocation ◽  
Leaf Size ◽  
Woody Biomass ◽  
Dry Weight ◽  
Curvilinear Relationship ◽  
Leaf Fall ◽  
Area Index ◽  
Short Rotation ◽  
Annual Biomass

Nitrogen treatment consisted of spring applications of ammonium nitrate at the rate of 167 kg N•ha−1•year−1 repeated for 3 years starting in the 2nd year after the planting of six Populus hybrids. No response to fertilizer was evident either in bole growth or leaves in year 2, but in year 3, fertilization caused a 14% increase in leaf size (upper terminal leaves), a 54% increase in leaf-fall mass, and a 58% increase in leaf area index (L, m2•m−2). Leaf and canopy responses were not as large in year four, i.e., a 32% increase in leaf-fall mass and a 31% increase in L. Biomass response to nitrogen, reported in an earlier paper, was a 24% increase in dry weight at the end of 4 years. This total was the result of a very large and significant dry weight response to nitrogen in year 3 (about 40%), and a small, nonsignificant response of about 8% in year 4. Leaf-fall means ranged from 3.3 Mg•ha−1•year−1 in year 3 on control plots to 5.8 Mg•ha−1•year−1 on fertilized plots in year 4. Means for L ranged from 3.8 on control plots in year 3 to 8.5 on fertilized plots in year 4. Plotting annual production of aboveground woody biomass versus L revealed a curvilinear relationship described by the polynomial model y = 6.92x − 0.18x2 (r2 = 0.963), where y is the current annual biomass production in Mg•ha−1•year−1 and x = L. Calculation of the extinction coefficient (k) in the Beer–Lambert equation indicated decreased efficiency of the canopies in capturing light in year 4 (k = 0.48) compared with year 3 (k = 0.63). Fertilization had no effect on k in either year. Efficiency of the leaf area in producing biomass per unit of L (E) was lower (though not significantly) on fertilized plots than on control plots (E = 5.3 vs. 5.8 Mg•ha−1•year−1•L−1, respectively). In contrast with the indications from the k-values, E appeared to increase in year 4 compared with year 3 (5.8 vs. 5.4 Mg•ha−1•year−1•L−1, respectively), a contradiction that could arise from a change in carbon allocation favoring aboveground over belowground tissues. The limited response of woody biomass to nitrogen in year 4 appears to be a consequence of the large increase in canopy density (L) on the control plots in that year compared with fertilized plots. The average for L on control plots was higher in year 4 than it was on fertilized plots in year 3. Also contributing to the limited response to nitrogen in year 4 were lower leaf area efficiencies at the high levels of L on the fertilized plots in year 4.

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.

Nutritional concerns in selection of black cottonwood and hybrid clones for short rotation

1986 ◽  
Vol 16 (4) ◽  
pp. 860-863 ◽  
Author(s):  
Paul E. Heilman ◽  
R. F. Stettler
Keyword(s):  
Nutrient Use Efficiency ◽  
Woody Biomass ◽  
Dry Weight ◽  
Utilization Efficiency ◽  
High Yield ◽  
Leaf Fall ◽  
Black Cottonwood ◽  
Short Rotation ◽  
Rooting Of Cuttings ◽  
P Utilization

Nitrogen in leaf fall and in aboveground tissue of close-spaced 4-year-old clones of black cottonwood (Populustrichocarpa Torr. & Gray), Populustrichocarpa × Populusdeltoides Bartr. hybrids, and a 'Robusta' clone was determined. Phosphorus and calcium in the harvested material were also determined. Dry weight of leaf fall varied from 4.4 to 6.6 Mg ha−1 year−1 and it contained from 62 to 84 kg N ha−1. Estimated annual uptake of N in aboveground biomass and leaves ranged from 95 to 276 kg N ha−1 and was largely related to clonal productivity. Aboveground dry weight of woody biomass at the end of 4 years varied from 29 to 111 Mg ha−1 with the two trichocarpa × deltoides hybrids being the highest producers. Nutrients contained in aboveground woody biomass differed greatly among clones in this study, ranging from 95 to 420 kg N ha−1, 14 to 105 kg P ha−1, and 80 to 288 kg Ca ha−1. The N and P utilization efficiency of clones ranked as follows: black cottonwood > new hybrids > 'Robusta'. For Ca, the ranking was as follows: black cottonwood = new hybrids > 'Robusta'. From the standpoint of nutrient-use efficiency, as well as high yield, rooting of cuttings, sprouting after harvest, and other desirable features, black cottonwood offers clear advantages to be captured in breeding programs for short-rotation culture.

Two Methods for the Rapid Assessment of Leaf Yields of Erythroxylum coca `Coca'

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 482e-483
Author(s):  
Mary C. Acock
Keyword(s):  
Leaf Area ◽  
Rapid Assessment ◽  
Leaf Size ◽  
Dry Weight ◽  
Branch Number ◽  
Area Index ◽  
Production Methods ◽  
Canopy Volume ◽  
Pca Method ◽  
Leaf Dry Weight

To determine the extent of world coca (Erythroxylum) production, methods for rapid estimation of yield (leaf mass) are required. The objective of this research was to compare two methods for rapidly acquiring data to estimate yield. The plant canopy analyzer (PCA) method was based on measuring canopy light interception with the LI-COR PCA, calculating leaf area index (L), and converting L to leaf dry weight using specific leaf area (SLA) values. The canopy subsample method was based on calculating leaf dry weight of a subsample from leaf and branch number, leaf size, and SLA, then multiplying by the ratio of the canopy volume to the subsample volume. PCA measurements underestimated leaf yields when values of L were ≥1.0. PCA estimates could be corrected by adjusting for the observed difference between leaf yields and PCA estimates. The corrected PCA and canopy subsample methods had errors of similar magnitude, both slightly underestimating yield. Both methods performed well when tested against data from a subsequent harvest. The canopy subsample method uses simple equipment and can be ap-plied in almost any environmental condition, but requires more time in the field than the PCA method. The corrected PCA method has slightly less random error than the canopy subsample method but requires expensive equipment, uniform light conditions in the field of view, and cannot be applied when raining.

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

2012 ◽  
Vol 10 (1) ◽  
pp. 16-22 ◽  
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

Characteristics of the canopy, root system and grain yield of a crop of Lupinus angustifolius cv. Unicrop

1975 ◽  
Vol 26 (3) ◽  
pp. 497 ◽  
Author(s):  
EAN Greenwood ◽  
P Farrington ◽  
JD Beresford
Keyword(s):  
Carbon Dioxide ◽  
Grain Yield ◽  
Leaf Area ◽  
Time Course ◽  
Dry Weight ◽  
Grain Filling ◽  
Main Axis ◽  
Carbon Dioxide Exchange ◽  
Area Index ◽  
Plant Parts

The time course of development of a lupin crop was studied at Bakers Hill, Western Australia. The aim was to gain insight into the crop factors influencing yield. Weekly measurements were made of numbers and weights of plant parts, and profiles of roots, leaf area and light interception. A profile of carbon dioxide in the crop atmosphere was taken at the time of maximum leaf area, and the net carbon dioxide exchange (NCE) of pods was estimated for three successive weeks. The crop took 10 weeks to attain a leaf area index (LAI) of 1 and a further 9 weeks to reach a maximum LAI of 3.75, at which time only 33% of daylight reached the pods on the main axis. Once the maximum LAI was attained at week 19, leaf fall accelerated and rapid grain filling commenced almost simultaneously on all of the three orders of axes which had formed pods. Measurements of NCE between pods on the main axis and the air suggest that the assimilation of external carbon dioxide by the pods contributed little to grain filling. Grain dry weight was 2100 kg ha-1 of which 30%, 60% and 10% came from the main axis, first and second order apical axes respectively. Only 23% of the flowers set pods and this constitutes an important physiological limitation to grain yield.

scholarly journals Representing winter wheat in the Community Land Model (version 4.5)

2017 ◽  
Vol 10 (5) ◽  
pp. 1873-1888 ◽  
Author(s):  
Yaqiong Lu ◽  
Ian N. Williams ◽  
Justin E. Bagley ◽  
Margaret S. Torn ◽  
Lara M. Kueppers
Keyword(s):  
Heat Flux ◽  
Winter Wheat ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Latent Heat Flux ◽  
Carbon Allocation ◽  
Net Ecosystem Exchange ◽  
Area Index ◽  
Community Land Model ◽  
The Us

Abstract. Winter wheat is a staple crop for global food security, and is the dominant vegetation cover for a significant fraction of Earth's croplands. As such, it plays an important role in carbon cycling and land–atmosphere interactions in these key regions. Accurate simulation of winter wheat growth is not only crucial for future yield prediction under a changing climate, but also for accurately predicting the energy and water cycles for winter wheat dominated regions. We modified the winter wheat model in the Community Land Model (CLM) to better simulate winter wheat leaf area index, latent heat flux, net ecosystem exchange of CO2, and grain yield. These included schemes to represent vernalization as well as frost tolerance and damage. We calibrated three key parameters (minimum planting temperature, maximum crop growth days, and initial value of leaf carbon allocation coefficient) and modified the grain carbon allocation algorithm for simulations at the US Southern Great Plains ARM site (US-ARM), and validated the model performance at eight additional sites across North America. We found that the new winter wheat model improved the prediction of monthly variation in leaf area index, reduced latent heat flux, and net ecosystem exchange root mean square error (RMSE) by 41 and 35 % during the spring growing season. The model accurately simulated the interannual variation in yield at the US-ARM site, but underestimated yield at sites and in regions (northwestern and southeastern US) with historically greater yields by 35 %.

scholarly journals Growth And Yield of Sorghum (Sorghum bicolor (L.) Moench) Varities in Sokoto Sudan Savanna of Nigeria

2021 ◽  
Vol 25 (8) ◽  
pp. 1513-1518
Author(s):  
A.S. Gunu ◽  
M. Musa
Keyword(s):  
Leaf Area ◽  
Block Design ◽  
Dry Weight ◽  
Growth And Yield ◽  
Area Index ◽  
Days To Heading ◽  
Number Of Leaves ◽  
Total Dry Weight ◽  
Sudan Savanna ◽  
Stalk Weight

Field trial was carried out during the 2019 rainy season (June to October) at the Dryland Teaching and Research Farm of the Faculty of Agriculture, Usmanu Danfodiyo University, Sokoto to determine the growth and yield of sorghum varieties in the study area. The treatments consisted of five (5) sorghum varieties (Samsorg 45, Samsorg 46, Janjari, Yartawa and Jardawa), the treatments were laid out in a Randomized Complete Block Design (RCBD) replicated three (3) times. Data were collected on the growth and yield of the crop. Janjari and Jardawa varieties were higher in plant height. Jardawa and Yartawa varieties were higher in number of leaves. Janjari and Yartawa varieties were higher in total dry weight. Janjari, Jardawa and Yartawa varieties were higher in harvest index. Yartawa variety was higher in leaf area, leaf area index and 1000-grain weight. Jardawa variety was higher in panicle length. Janjari variety was early in number of days to heading, flowering, and maturity and was higher in dry stalk weight. The grain yield (249 – 1506kg ha-1 ) was higher in Janjari and Yartawa varieties (1268 – 1506 kg ha-1). Based on the findings of this research, it could be concluded that Janjari and Yartawa varieties performed better than other varieties in the study area.

scholarly journals Effect of Foliar Application of Growth Regulators on Vegetative and Physiological Growth Parameters in Ajowan (Trachyspermum ammi L. Sprague)

2020 ◽  
pp. 100-109
Author(s):  
Y. Rajasekhara Reddy ◽  
G. Ramanandam ◽  
P. Subbaramamma ◽  
A. V. D. Dorajeerao
Keyword(s):  
Leaf Area ◽  
Foliar Application ◽  
Growth Parameters ◽  
Block Design ◽  
Foliar Spray ◽  
Dry Weight ◽  
Area Index ◽  
Chlorophyll Contents ◽  
Trachyspermum Ammi ◽  
Number Of Leaves

A field experiment was carried out during rabi season of 2018-2019, at college farm, College of Horticulture, Dr. Y.S.R. Horticultural University, Venkataramannagudem, West Godavari District, Andhra Pradesh. The experiment was laidout in a Randomised Block Design with eleven treatments (viz., T1- NAA @ 50 ppm, T2-NAA @ 100 ppm, T3-GA3 @ 50 ppm,  T4-GA3 @ 100 ppm, T5-Thiourea @ 250 ppm, T6-Thiourea @ 500 ppm, T7-28-Homobrassinolide @ 0.1 ppm, T8-28-Homobrassinolide @ 0.2 ppm, T9-Triacontinol @ 2.5 ppm, T10-Triacontinol @ 5 ppm, T11-(Control) Water spray) and three replications. The treatments were imposed at 30 and 45 DAT in the form of foliar spray. Foliar application of GA3@ 100 ppm (T4) had recorded the maximum plant height (108.20 cm), leaf area (9.53 cm2) and leaf area index (0.74). Foliar application of thiourea @ 250 ppm (T5) had recorded the maximum values with respect to number of primary branches (15.03 plant-1), number of secondary branches (83.40 plant-1), plant spread (1793 cm2 plant-1), fresh weight (376.29 g plant-1), dry weight (103.54 g plant-1) and number of leaves plant-1((298.8). The same treatment (T5) had recorded the highest values with respect to crop growth rate (1.44 gm-2d-1), chlorophyll-a (1.40 mg g-1), chlorophyll-b (0.076 mg g-1) and total chlorophyll contents (1.48 mg g-1) in the leaves.

Influence of different organic manures on growth, yield and mineral nutrient accumulation in lettuce (Lactuca sativa L.)

2021 ◽  
Vol 30 (2) ◽  
pp. 159-168
Author(s):  
Shabnur Chowdhury ◽  
MK Rahman
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Lactuca Sativa ◽  
Dry Weight ◽  
Organic Manure ◽  
Leaf Number ◽  
Nutrient Accumulation ◽  
Area Index ◽  
Organic Manures ◽  
Lactuca Sativa L

Effects of organic manures on growth and yield of lettuce (Lactuca sativa L.) and nutrient accumulation in its leaves was examined. The experiment was conducted in a completely randomized design (CRD) replicated thrice with ten treatments involving nine organic manures and a control treatment. Growth parameters viz. plant height, leaf number, leaf length, leaf area, leaf area index and fresh and dry weight of leaf, stem and root were assessed. The highest height (23.69 cm), longest leaf (32.18cm), leaf area (5883.43cm2), leaf area index (6.434), fresh weight (85.41 g) and dry weight (42.73 g) were found in Payel organic manure. The maximum leaf number (27) was recorded in Approshika organic manure. The maximum content of nitrogen (6.12%), phosphorus (1.83%), potassium (4.11%) and Sulphur (1.69%) were observed in Payel organic manure. The best growth performance and nutrient accumulation was observed in Payel organic manure. Dhaka Univ. J. Biol. Sci. 30(2): 159-168, 2021 (July)

Canopy Dynamics of Eucalyptus Maculata Hook. I. Distribution and Dynamics of Leaf Populations

1984 ◽  
Vol 32 (4) ◽  
pp. 387 ◽  
Author(s):  
EW Pook
Keyword(s):  
Water Supply ◽  
Leaf Area ◽  
Shoot Growth ◽  
Temperature Limit ◽  
Leaf Fall ◽  
Leaf Production ◽  
Area Index ◽  
Average Size ◽  
Non Destructive

The canopy dynamics of a regenerated 16-year-old stand of pole and sapling E. maculata were studied for 2½ years by repetitive non-destructive measurements in tree crowns accessed from a 20 m high scaffold tower. Average canopy leaf area density over a sample plot of 36 m2 was 0.23 m2 m-3 at a leaf area index of 4.3. Some 75% of leaf area was held in the canopies of overstorey eucalypts above 10 m in height. Average size of leaves increased gradually from top to bottom of tree canopies. Foliage production was usually concentrated in the upper crowns of trees where there was a higher proportion of active shoots, more frequent growth flushes and more rapid turnover of leaves than in lower canopy layers. Leaf area in the upper canopy fluctuated widely but increased in the long term, in mid canopy was more or less maintained and in lowest canopy declined. Crops of developing flower buds present on uppermost branches delayed and/or reduced shoot growth. Foliage production occurred in all months of the year. There was a unimodal annual rhythm of growth rate reaching a maximum in summer and a minimum in winter. Variable water supply, however, influenced production to peak in spring, summer or autumn. No shoot growth occurs in E. maculata at Kioloa when daily mean temperature (averaged for weekly intervals) falls below c. 10½C in winter. An upper temperature limit for growth could not be defined. The species apparently lacks dormancy mechanisms. Shoot growth is 'opportunistic' and occurs whenever environmental conditions are favourable. Patterns of leaf production and leaf fall were variable but peaks showed a general synchrony. Leaf fall, however, tended to lag behind leaf production. Leaves of all ages were shed but main losses were from older cohorts. Some 49% (s.d.±18%) of new leaves were lost while still small or immature, mainly during periods of vigorous shoot growth or low water supply. Browse of immature foliage was light. Normal senescence and leaf fall accounted for almost the entire loss of mature foliage.

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