Corrigendum - Leaf area development in barley—model construction and response to soil moisture status

1995 ◽  
Vol 46 (5) ◽  
pp. 845
Author(s):  
SP Milroy ◽  
PJ Goyne
Keyword(s):  
Soil Water ◽  
Leaf Area ◽  
Logistic Function ◽  
Leaf Expansion ◽  
Research Station ◽  
Area Index ◽  
Whole Plant ◽  
The Relationship ◽  
Area Development ◽  
Leaf Area Development

A model to simulate leaf area development for barley at the whole plant level was constructed. Data for leaf area development in the absence of soil water stress were collected from irrigated field trials grown at Hermitage Research Station, near Warwick, Queensland, in 1990. The response of leaf area expansion to soil water status was measured in a glasshouse trial. In the model, green leaf area per plant (GPLA) is derived as the difference between total leaf area produced per plant (TPLA) and senesced leaf area (SPLA). TPLA and SPLA are described by logistic functions of thermal time. Two types of senescence are included: that due to ageing of the whole plant (ontogenetic senescence) and senescence associated with the development of large canopies (light-induced senescence). The onset of ontogenetic senescence is linked to anthesis, whereas light-induced senescence occurs if the leaf area index of the crop exceeds 5.5. Leaf expansion of plants in pots varying in the fraction of transpirable soil water available (FTSW) was compared with leaf expansion of those in well-watered pots three times per week. The relationship between relative leaf expansion (RLE) and FTSW was described by a logistic function (r2 = 0.96). A 50% reduction in RLE occurred when FTSW = 0.34. Similarly, a logistic function described the relationship between relative transpiration (RT) and FTSW (r2 = 0.96). A 50% reduction in RT occurred when FTSW = 0.17. Potential leaf expansion as predicted by the non-stressed model was reduced in response to moisture stress via a ramp function relating RLE to RT. The model gave an unbiased prediction of the leaf area dynamics for 21 rainfed and irrigated crops of barley grown in southern Queensland between 1986 and 1993 (RMSD = 1.09 m2 m-2, r2 = 0.75, n = 76). Precision may have been reduced by the lack of information available on parameters for soil water balance when barley is grown on a range of soil types.

Leaf area development in barley—model construction and response to soil moisture status

1995 ◽  
Vol 46 (5) ◽  
pp. 845
Author(s):  
SP Milroy ◽  
PJ Goyne
Keyword(s):  
Soil Water ◽  
Leaf Area ◽  
Logistic Function ◽  
Leaf Expansion ◽  
Research Station ◽  
Area Index ◽  
Whole Plant ◽  
The Relationship ◽  
Area Development ◽  
Leaf Area Development

A model to simulate leaf area development for barley at the whole plant level was constructed. Data for leaf area development in the absence of soil water stress were collected from irrigated field trials grown at Hermitage Research Station, near Warwick, Queensland, in 1990. The response of leaf area expansion to soil water status was measured in a glasshouse trial. In the model, green leaf area per plant (GPLA) is derived as the difference between total leaf area produced per plant (TPLA) and senesced leaf area (SPLA). TPLA and SPLA are described by logistic functions of thermal time. Two types of senescence are included: that due to ageing of the whole plant (ontogenetic senescence) and senescence associated with the development of large canopies (light-induced senescence). The onset of ontogenetic senescence is linked to anthesis, whereas light-induced senescence occurs if the leaf area index of the crop exceeds 5.5. Leaf expansion of plants in pots varying in the fraction of transpirable soil water available (FTSW) was compared with leaf expansion of those in well-watered pots three times per week. The relationship between relative leaf expansion (RLE) and FTSW was described by a logistic function (r2 = 0.96). A 50% reduction in RLE occurred when FTSW = 0.34. Similarly, a logistic function described the relationship between relative transpiration (RT) and FTSW (r2 = 0.96). A 50% reduction in RT occurred when FTSW = 0.17. Potential leaf expansion as predicted by the non-stressed model was reduced in response to moisture stress via a ramp function relating RLE to RT. The model gave an unbiased prediction of the leaf area dynamics for 21 rainfed and irrigated crops of barley grown in southern Queensland between 1986 and 1993 (RMSD = 1.09 m2 m-2, r2 = 0.75, n = 76). Precision may have been reduced by the lack of information available on parameters for soil water balance when barley is grown on a range of soil types.

Leaf area development on different shoot types in a young aspen stand and its effect upon production

1970 ◽  
Vol 48 (10) ◽  
pp. 1801-1804 ◽  
Author(s):  
D. F. W. Pollard
Keyword(s):  
Leaf Area ◽  
Total Production ◽  
Short Shoot ◽  
Area Index ◽  
Young Leaves ◽  
Long Shoots ◽  
Short Shoots ◽  
Area Development ◽  
Leaf Area Development ◽  
Photosynthetic Efficiencies

Different shoot types in aspen crowns carried leaves of different ages; leaders continued to produce leaves until early August and always carried some young leaves, whereas short shoots completed development by mid-June. Development of foliage on long shoots was intermediate between that on leaders and short shoots. Leaf area index of the 6-year-old stand reached a maximum of 2.4, of which 2.1 was contributed by short-shoot foliage. The rest was formed by leaders and long shoots. Young leaves on leaders and long shoots were not sufficient to influence total production in the stand appreciably, even though young aspen leaves may have high photosynthetic efficiencies. These young leaves could, however, influence height growth and lateral development of the canopy.

Effects of drought on leaf area development, biomass production and nitrogen uptake of durum wheat grown in a Mediterranean environment

1995 ◽  
Vol 46 (1) ◽  
pp. 99 ◽  
Author(s):  
F Giunta ◽  
R Motzo ◽  
M Deidda
Keyword(s):  
Durum Wheat ◽  
Leaf Area ◽  
Nitrogen Uptake ◽  
Dry Matter ◽  
Growing Season ◽  
Dry Matter Accumulation ◽  
Mediterranean Environment ◽  
Area Index ◽  
Area Development ◽  
Leaf Area Development

A field experiment was carried out in Sardinia (Italy) on durum wheat to analyse the effects of different moisture treatments, irrigated (I), rainfed (R) and stressed (S), on leaf area index (LAI), radiation intercepted (Q) and water use (WU), efficiency of conversion of radiation and water into dry matter (RUE and WUE), nitrogen uptake and carbon and nitrogen partitioning in the above-ground part of the plant. In the period between beginning of stem elongation and heading, drought affected the maximum LA1 in the most stressed treatment (4.7 in S v. about 6.9 in R and I), but not Q and WU. RUE was also lowered by drought in this period (0.68 in S v. about 0.95 g MJ-1 in R and I) as a reduced biomass was recorded in S at heading (528gm-2 in S v. 777 g m-2 on average in R and I). In contrast with the previous period, the reduction in LA1 between heading and maximum ear weight (MEW) determined a significant reduction in Q and WU, WUE and RUE, resulting, ultimately, in notable differences in the total biomass produced until MEW (1203, 930 and 546 gm-2 in I, R and S respectively). The amount of stem reserves relocated to the grain decreased as the level of stress increased, going from 223gm-2 in I to 9gm-2 in S and was accumulated almost entirely (from 76% of the total in I to 100% in S), in the post-heading period. Nitrogen percentage was not affected by the treatments applied apart from the higher values in stem and flag leaf in S later in the growing season due to an inhibition of nitrogen translocation in S. The total nitrogen uptake was lower in S (12.3gm-2) than in I (16.6gm-2) only as a consequence of the different dry matter accumulation patterns. The importance of WUE in this type of Mediterranean environment is discussed, with particular concern to the key role of modulation of leaf area development through the growing season.

Growth and Productivity of Tapioca (Manihot utilissima)—I. Leaf Characteristics and Yield

1969 ◽  
Vol 5 (3) ◽  
pp. 183-194 ◽  
Author(s):  
C. N. Williams ◽  
S. M. Ghazali
Keyword(s):  
Leaf Area ◽  
Morphological Characteristics ◽  
Leaf Size ◽  
Time Orientation ◽  
Leaf Characteristics ◽  
Horizontal Orientation ◽  
Leaf Properties ◽  
The Relationship ◽  
Area Development ◽  
Leaf Area Development

SummaryThe shoots of high, medium and low yielding clones of tapioca were examined to see whether yield was associated with morphological characteristics of the foliage and/or with leaf area development. The lowest yielding variety had the highest leaf area per stem, and vice versa, differences in leaf area being mainly due to differences in leaf size. Leaves of the highest yielding variety possessed attenuated lobes, which tended to have a more vertical mid-day orientation, whereas the lowest yielding variety possessed large broad-lobed leaves with more horizontal orientation. The intermediate variety had acutely attenuated lobes and showed a much more vertical day-time orientation. The relationship between the leaf properties and canopy efficiency is discussed.

Effects of nitrogen supply on canopy development of maize and sunflower

2011 ◽  
Vol 62 (12) ◽  
pp. 1045 ◽  
Author(s):  
A. M. Massignam ◽  
S. C. Chapman ◽  
G. L. Hammer ◽  
S. Fukai
Keyword(s):  
Leaf Area ◽  
Plant Density ◽  
Carbon Assimilation ◽  
Leaf Nitrogen ◽  
Area Index ◽  
Canopy Development ◽  
N Limitation ◽  
N Supply ◽  
Area Development ◽  
Leaf Area Development

Nitrogen (N) limitation reduces canopy carbon assimilation by directly reducing leaf photosynthesis, and by developmentally reducing the rate of new leaf area development and accelerating leaf senescence. Effective use of N for biomass production under N limitation may be considered to be a result of a trade-off between the use of N to maintain high levels of specific leaf nitrogen (SLN the amount of N per unit leaf area) for high photosynthetic rate versus using N to maintain leaf area development (leaf area index – LAI). The objective here is to compare the effects of N supply on the dynamics of LAI and SLN for two crops, maize (Zea mays L.) and sunflower (Helianthus annuus L.) that contrast in the structure and development of their canopy. Three irrigated experiments imposed different levels of N and plant density. While LAI in both maize and sunflower was reduced under N limitation, leaf area development was more responsive to N supply in sunflower than maize. Observations near anthesis showed that sunflower tended to maintain SLN and adjust leaf area under reduced N supply, whereas maize tended to maintain leaf area and adjust SLN first, and, when this was not sufficient, SLN was also reduced. The two species responded differently to variation in N supply, and the implication of these different strategies for crop adaptation and management is discussed.

Variation in leaf area development and its effect on water use, yield and harvest index of droughted wheat

1987 ◽  
Vol 38 (6) ◽  
pp. 983 ◽  
Author(s):  
RA Richards ◽  
TF Townley-Smith
Keyword(s):  
Grain Yield ◽  
Leaf Area ◽  
Water Use ◽  
Harvest Index ◽  
Leaf Growth ◽  
Unit Length ◽  
Nonlinear Function ◽  
Area Index ◽  
Area Development ◽  
Leaf Area Development

Genotypes, chosen because of their variation in flowering, tillering and early leaf growth, were evaluated in 1 m long tubes in a glasshouse. These traits were selected for two reasons: firstly, because it was presumed they influence leaf area development and hence the water use, harvest index and yield of droughted wheat; secondly, because they are amenable to genetic manipulation and therefore can be selected in a breeding program. Four drought treatments were imposed in each of two seasons. The treatments and cultural conditions simulated droughts encountered by field-grown crops. Grain yield varied according to the amount of growth and water use before and after anthesis in relation to soil water supply. In the wettest treatments where plants had adequate water up to anthesis but were droughted thereafter (akin to a wet mediterranean-type environment), grain yield was positively associated with the amount of preanthesis growth. In the drier treatments, where droughts were sustained from before anthesis, genotypes having traits that reduced leaf area index saved more water for use after anthesis and had a higher harvest index and grain yield. However, pre-anthesis growth was also important, as it was estimated that in the driest treatments up to 60% of the grain dry weight was formed from reserves present at anthesis. These reserves represented up to 15% of the above-ground biomass at anthesis. Harvest index (y) was a nonlinear function of the proportion of water used after anthesis (x), y = 0.10 + 0.13 ln(x), r2 = 0.82 (P < 0.01).The determinate tillering or 'uniculm' wheats, although having some advantages over conventional tillering lines when sown at the same density, were largely indistinguishable from conventional wheats in their water use pattern when sown at twice the density. However, at both densities they had a higher stem weight per unit length and a higher specific leaf weight than conventional wheats, and this resulted in them having a lower harvest index and grain yield. These pleiotropic effects may reduce the possible advantages of these wheats, that is a reduced maximum leaf area and no sterile tillers, in dry environments.

Predicting leaf area development in response to temperature in three tropical annual forage legumes

1999 ◽  
Vol 50 (2) ◽  
pp. 253 ◽  
Author(s):  
B. C. Pengelly ◽  
R. C. Muchow ◽  
F. P. C. Blamey
Keyword(s):  
Leaf Area ◽  
Plant Density ◽  
Thermal Time ◽  
Forage Legumes ◽  
Degree Days ◽  
South Eastern ◽  
Rate Of Increase ◽  
The Relationship ◽  
Area Development ◽  
Leaf Area Development

Ley legumes are an important option in nitrogen (N) management in cropping–livestock systems in Australia’s northern cropping region. The complexity of managing N and water in these systems is increasingly being aided by the use of crop models which require quantitative estimates of the various components of growth. A study to predict plant leaf area (PLA) of 3 tropical forage legumes as a function of temperature under irrigated conditions was conducted at Gatton, south-eastern Queensland. The legumes were phasey bean [Macroptilium lathyroides (L.) Urban.], vigna [Vigna trilobata (L.) Verdc.], and sesbania (Sesbania cannabina Retz.). The PLA was to be predicted by establishing a relationship between plastochron index (PI) and accumulated thermal time, and then between PLA and PI. Daily rate of increase in PI (DIPI) was strongly related to accumulated thermal time in all species, with DIPI higher for phasey bean (0.51 degree-days) and sesbania (0.54 degree-days) than for vigna (0.14 degree-days). At a plant density of 50 plants/m2, the relationship between PI and PLA was largely dependent upon the proportion of PLA originating from branches rather than from the main stem. In sesbania, <20% of the PLA was contributed from leaves originating from branches, compared with about 40% in phasey bean and about 75% in vigna. The slope of the linear component of the relationship between PLA and PI in sesbania (85 cm2) was slightly less than the maximum leaf area per node recorded. The comparable slope for phasey bean was 57 cm2, being greater than the area of any individual leaf (40–50 cm2) because of the greater contribution of leaves originating from branches. In vigna, the very large contribution of leaves originating from branches to PLA, together with the slower DIPI for that species, resulted in the relationship between PI and PLA being much steeper than in either of the other species. The parameters developed for each species were successfully validated using independent data from other experiments in south-eastern Queensland. Increase in PLA in response to accumulated thermal time can be successfully predicted for these 3 tropical legumes at the set plant density. The successful prediction of PLA for legumes with a high degree of branching is of special significance, as it indicates that these methods may have application in predicting leaf growth in legumes which are being grazed and which have a number of active growing points. Nevertheless, the stability of the derived parameters needs to be assessed under a range of plant densities before they can be widely used to predict leaf area development in ley legumes.

GROWTH HABIT AND ROW WIDTH EFFECTS ON LEAF AREA DEVELOPMENT AND LIGHT INTERCEPTION OF FIELD BEANS

1979 ◽  
Vol 59 (1) ◽  
pp. 191-199 ◽  
Author(s):  
T. R. GARDINER ◽  
L. E. CRAKER ◽  
D. M. VIETOR
Keyword(s):  
Leaf Area ◽  
Growth Habit ◽  
Area Index ◽  
A Value ◽  
Row Width ◽  
Late Initiation ◽  
Short Season ◽  
Area Development ◽  
Leaf Area Development ◽  
Field Beans

Leaf area development and percent interception of photosynthetically-active radiation (PAR) were measured to compare a determinate, bush cultivar with an indeterminate, climbing or pole cultivar of Phaseolus vulgaris L. in a short season environment. Each cultivar was grown at a wide (91 cm) and narrow (45.5 cm) interrow spacing to evaluate the growth habit effects under currently recommended plant spacings. Percent PAR interception and leaf area index (LAI) were determined on five sampling dates and PAR penetrating through the canopy was recorded on four of those dates. A large reduction of LAI of the bush cultivar and continued expansion of leaves in the upper portion of the pole canopy resulted in a greater percentage of PAR interception by the pole cultivar than by the bush cultivar at 72 days after planting. The taller, unlodged vine-type canopy of the pole cultivar intercepted nearly 50% more PAR than the bush cultivar when the LAI of the two cultivars was comparable at 96 days. The continued leaf expansion and late initiation of pod filling limited the duration of rapid pod filling of the pole cultivar in the short season environment. LAI and percent interception of PAR by the bush cultivar were greater at the 45.5-cm than at the 91-cm spacing at 41 and 54 days. The maximum LAI and percent interception were only 3.2 and 82%, respectively, for the 91-cm spacing of the bush cultivar. LAI of the 45.5-cm spacing of the bush cultivar was reduced to a value less than that of the 91-cm spacing from 54 to 72 days, but percent interception by the 45.5-cm spacing was still greater. Percent interception of PAR at 41 days was greater at the 45.5-cm spacing than at the 91-cm spacing of the pole bean, but interrow spacing did not affect LAI or percent interception on the other dates.

An analysis of the effect of weed competition on growth and yield attributes in sorghum (Sorghum vulgare), cowpeas (Vigna unguiculata) and green gram (Vigna aureus)

1973 ◽  
Vol 81 (3) ◽  
pp. 449-453 ◽  
Author(s):  
B. A. C. Enyi
Keyword(s):  
Grain Yield ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Grain Weight ◽  
Green Gram ◽  
Area Index ◽  
Yield Attributes ◽  
Area Development ◽  
Leaf Area Development ◽  
Better Than

SUMMARYIn each of the crops studied, weeding increased grain yield, weeding 2 weeks after sowing being better than weeding either four or eight weeks after sowing and weeding two and four weeks after sowing being better than weeding either two and eight weeks or four and eight weeks aftersowing. Weeding thrice (two, four and eight weeks after sowing) was significantly superior to all the other weeding treatments. Weeding increased leaf area index, dry weight of side and mainstem and number of mature pods at harvest in green gram and cowpeas. In sorghum, apart from increasing leaf area index, it also increased the length of ears and grain weight per unit lengthof ear. The weeding treatments affected grain yield in cowpeas and green gram due totheir influence on leaf area development, development of the main and side stems and on the number of mature pods produced at harvest. The effect of the weeding treatments on grain yield of sorghum was due to their influence on leaf area development, length of ear and grain weight perunit length of ear.

scholarly journals Modeling the Effects of Drought Stress on Leaf Development in a Brassica oleracea Doubled Haploid Population Using Two-phase Linear Functions

2009 ◽  
Vol 134 (5) ◽  
pp. 543-552 ◽  
Author(s):  
Ralf Uptmoor ◽  
Mildred Osei-Kwarteng ◽  
Susanne Gürtler ◽  
Hartmut Stützel
Keyword(s):  
Drought Stress ◽  
Soil Water ◽  
Leaf Area ◽  
Water Status ◽  
Doubled Haploid Population ◽  
Two Phase ◽  
Soil Water Status ◽  
Effects Of Drought ◽  
Area Development ◽  
Leaf Area Development

The combination of quantitative trait loci (QTL) analysis and ecophysiological modeling has been suggested as an approach to reveal the genetic basis of complex traits since phenotypes change with time and environmental conditions and the variation within populations can be described by genotype-specific parameterization of response curves on time and influential environmental factors. The objectives of the present study are a genotype-specific parameterization of a model describing leaf area development under well-watered and drought stress conditions, the use of QTL for estimating model input parameters, an evaluation of the model, and a comparison of the genotype-specific and QTL-based model parameterization. We used a two-phase linear function to describe preflowering leaf area development in a Brassica oleracea L. doubled haploid population. To illustrate effects of drought on leaf growth, the function was combined with a plateau function, which estimates the soil water status at which stress effects begin to reduce leaf expansion, a genotype-specific slope of the response to soil water status, and the soil water status at which leaf expansion becomes zero. A total number of 14 QTL were detected on the parameters of the two-phase linear function describing preflowering leaf area development and the plateau function describing the effects of drought on leaf area development. Nine of these QTL colocalized to QTL detected on data of static leaf area measurements and osmotic adjustment. The entire model was able to distinguish between genotypes during later growth stages under well-watered and drought stress conditions. However, the predictability was largely reduced when drought stress became more severe at the final measurement dates. Independent evaluation trials showed that the accuracy of the model was on the same level or even higher when genotype specific input parameters were replaced by allele-specific QTL effects.

Sign in / Sign up

Export Citation Format

Share Document