AN ANALYSIS OF DRY MATTER PRODUCTION OF DOUGLAS-FIR SEEDLINGS IN RELATION TO TEMPERATURE AND LIGHT INTENSITY

1967 ◽  
Vol 45 (11) ◽  
pp. 2063-2072 ◽  
Author(s):  
Holger Brix
Keyword(s):  
Light Intensity ◽  
Leaf Area ◽  
Dry Matter ◽  
Douglas Fir ◽  
Dry Matter Production ◽  
Dry Matter Distribution ◽  
Pronounced Increase ◽  
Light Intensities ◽  
Matter Production ◽  
Net Assimilation

Seedlings of Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) were grown in growth chambers under all combinations of three temperatures (13, 18, and 24 °C) and three light intensities (450, 1000, and 1800 ft-c). Dry matter production of leaves, stem, and roots was determined at 65 and 100 days after germination. The leaf area produced per unit of leaf dry weight and the dry matter distribution to the plant organs was measured. Net assimilation rates between the ages of 65 and 100 days were calculated. Rates of photosynthesis per unit of leaf were determined at different light intensities and temperatures, and rates of respiration of plant top and of roots were found for different temperatures.Increasing light intensity affected dry matter production in two opposing ways: (i) it increased the rate of photosynthesis per unit leaf area, and (ii) it decreased the leaf area added per unit of dry matter produced. A pronounced increase in growth with increase in temperature from 13 to 18 °C was a result of a temperature influence on production of leaf area rather than the effect of photosynthesis per unit of leaf. Net assimilation rates decreased with increase in temperature at all light intensities.

Effects of Nitrogen, Phosphorus, Potassium and Magnesium on Growth of the Oil Palm

1972 ◽  
Vol 8 (4) ◽  
pp. 347-353 ◽  
Author(s):  
R. H. V. Corley ◽  
C. K. Mok
Keyword(s):  
Leaf Area ◽  
Oil Palm ◽  
Dry Matter ◽  
Fertilizer Application ◽  
Dry Matter Production ◽  
Matter Production ◽  
Oil Palms ◽  
Net Assimilation ◽  
Nitrogen Phosphorus ◽  
Bunch Yield

SUMMARYPotassium application appeared to increase dry matter production and yield of oil palms, primarily by increasing leaf area, while nitrogen increased both leaf area and net assimilation rate. Responses to phosphorus and magnesium were harder to interpret. Production of vegetative dry matter attained a fairly constant level at the higher rates of fertilizer application, while the ratio of bunch yield to total dry matter production was little affected by fertilizer treatments. The importance of these results for oil palm breeding, and their possible value in diagnosing fertilizer requirements, are briefly discussed.

Shading Responses of Purple and Yellow Nutsedges (Cyperus rotundusandC. esculentus)

Weed Science ◽  
1982 ◽  
Vol 30 (1) ◽  
pp. 25-30 ◽  
Author(s):  
David T. Patterson
Keyword(s):  
Leaf Area ◽  
Dry Matter ◽  
Plant Biomass ◽  
Cyperus Rotundus ◽  
Dry Matter Production ◽  
Purple Nutsedge ◽  
Yellow Nutsedge ◽  
Matter Production ◽  
Reduced Height ◽  
Net Assimilation

The effects of shade on dry-matter production, leaf area, and biomass partitioning in purple nutsedge (Cyperus rotundusL.) and yellow nutsedge (C. esculentusL.) were determined in a controlled-environment greenhouse with a day/night temperature regime of 32/26 C. For comparison with a full-light treatment, screening provided 40, 70, and 85% shade. Shading significantly reduced height of yellow nutsedge and dry-matter production, leaf-area production, and rhizome and tuber formation of both species. Shading decreased the partitioning of plant biomass into tubers and rhizomes and increased partitioning into leaves. Yellow nutsedge had a higher net-assimilation rate than purple nutsedge at all levels of shading, but the greater leaf-area duration or total amount of leaf area present in purple nutsedge resulted in greater dry-matter production by that species. The responses of the two species showed no differences in shade tolerance.

scholarly journals Nitrogen and potassium supply and the morphogenic and productive characteristics of marandu palisadegrass

2010 ◽  
Vol 39 (8) ◽  
pp. 1666-1675 ◽  
Author(s):  
Marcio Mahmoud Megda ◽  
Francisco Antonio Monteiro
Keyword(s):  
Leaf Area ◽  
Dry Matter ◽  
System Development ◽  
Block Design ◽  
Dry Mass ◽  
Dry Matter Production ◽  
Root System Development ◽  
Randomized Block Design ◽  
Matter Production ◽  
Specific Length

The objective of this work was to study morphogenic characteristics, and dry matter production of roots and shoots of marandu palisadegrass (Brachiaria brizantha cv. Marandu) submitted to combinations of nitrogen and potassium, in a nutritive solution, employing silica as substrate. The experiment was carried out in a greenhouse during the summer. It was used a 5² fractionated factorial scheme with 13 combinations of nitrogen and potassium, which were distributed in a randomized block design, with four replications. The nitrogen × potassium interaction was significant for the number of tillers and leaves, for leaf area, for shoots and root section dry mass, for total length and surface and specific length and surface in the roots. Production of aerial part dry mass positively correlated with the number of tillers and leaves and grass leaf area. Nitrogen rates modulated the root system development, and the root specific length and surface decreased when high rates of nitrogen and potassium were supllied. Nitrogen and potassium influence Marandu palisadegrass morphogenic characteristics, which are determinant for grass dry matter production.

Comparative Water Relations, Photosynthesis, and Growth of Soybean (Glycine max) and Seven Associated Weeds

Weed Science ◽  
1983 ◽  
Vol 31 (3) ◽  
pp. 318-323 ◽  
Author(s):  
David T. Patterson ◽  
Elizabeth P. Flint
Keyword(s):  
Glycine Max ◽  
Water Relations ◽  
Dry Matter ◽  
Stomatal Closure ◽  
Growth Dynamics ◽  
Dry Matter Production ◽  
Matter Production ◽  
Net Assimilation ◽  
Prickly Sida ◽  
Smooth Pigweed

Growth dynamics, water relations, and photosynthesis of soybean [Glycine max(L.) Merr. ‘Ransom’], common cocklebur (Xanthium pensylvanicumWallr.), jimsonweed (Datura stramoniumL.), prickly sida (Sida spinosaL.), sicklepod (Cassia obtusifoliaL.), smooth pigweed (Amaranthus hybridusL.), spurred anoda [Anoda cristata(L.) Schlect.], and velvetleaf (Abutilon theophrastiMedic.) were compared in a controlled-environment greenhouse programmed for 32C day and 23C night temperatures. Net photosynthetic rates, net assimilation rates, and water-use efficiency on a whole-plant or single-leaf basis were greatest in the C4-plant, smooth pigweed. Total dry-matter production at 29 days after planting was greatest in common cocklebur and least in jimsonweed. Interspecific differences in dry-matter production were highly positively correlated with leaf area duration and negatively correlated with net assimilation rate. Threshold leaf water-potential levels causing stomatal closure varied among species. The stomata of jimsonweed were the most sensitive to water stress and those of prickly sida were the least sensitive.

Depressed fodder quality and increased oestrogenic activity of lucerne infected with Pseudopeziza medicaginis

1980 ◽  
Vol 31 (6) ◽  
pp. 1103 ◽  
Author(s):  
WC Morgan ◽  
DG Parbery
Keyword(s):  
Protein Content ◽  
Leaf Area ◽  
Crude Protein ◽  
Dry Matter ◽  
Dry Matter Production ◽  
Crude Protein Content ◽  
Fodder Quality ◽  
Matter Production

As well as reducing dry matter production of lucerne, infection of 15 % of the leaf area by Pseucbpeziza medicaginis reduced digestibility by 14% and crude protein content by 16%. Infection caused oestrogenic activity in green lucerne.

Growth and yield studies of Lupinus angustifolius and L. albus in Victoria

1982 ◽  
Vol 22 (115) ◽  
pp. 76 ◽  
Author(s):  
KA Boundy ◽  
TG Reeves ◽  
HD Brooke
Keyword(s):  
Grain Yield ◽  
Leaf Area ◽  
Dry Matter ◽  
Yield Component ◽  
Early Flowering ◽  
Growth And Yield ◽  
Dry Matter Production ◽  
Sowing Time ◽  
Dry Matter Partitioning ◽  
Matter Production

The effect of serial planting on dry matter production, leaf area, grain yield and yield components cf Lupinus angustifoiius (cvv. Uniwhite, Uniharvest and Unicrop) and L. albus (cv. Ultra) was investigated in field plots at Rutherglen in 1973 and 1974. Delayed planting reduced dry matter production of all cultivars, and leaf area for Ultra. Differences in dry matter partitioning were observed between the late flowering Uniharvest, and the early flowering Unicrop and Ultra. In Uniharvest, delayed plantings resulted in a greater proportion of total dry matter being produced during the flowering phase, whereas the reverse was true for Unicrop and Ultra. The later flowering cultivars showed marked grain yield and yield component reduction with later sowing. Yields were reduced by 160.6 kg/ha and 222.5 kg/ha for each week's delay in sowing Uniharvest and Uniwhite, respectively. This effect was offset in the early flowering cultivars by greater development of lateral branches. In addition, when Unicrop and Ultra were planted in April, pod and flower abortion on the main stem resulted from low temperatures at flowering time. Optimum sowing time was early April for Uniwhite and Uniharvest, and early May for Unicrop and Ultra. Excellent vegetative growth under ideal moisture conditions highlighted the poor harvest indices of lupins and the scope for genetic improvement in the genus.

Effects of Time of Sowing and Phosphamidon (Dimecron) on Cowpea (Vigna unguiculata)

1974 ◽  
Vol 10 (2) ◽  
pp. 87-95 ◽  
Author(s):  
B. A. C. Enyi
Keyword(s):  
Grain Yield ◽  
Leaf Area ◽  
Vigna Unguiculata ◽  
Dry Matter ◽  
Dry Matter Production ◽  
Matter Production ◽  
Area Development ◽  
Leaf Area Development

SUMMARYApplication of dimecron to cowpea plants increased grain yield, its effect being more pronounced in widely spaced plants and those planted in March. Dimecron increased grain yield by encouraging greater leaf area development, by increasing the number of flowering inflorescences and the number of pods set per inflorescence, and by decreasing the number of shrivelled pods. March planting encouraged greater dry matter production than January and May planting. Dimecron application decreased the number of Ootheca beningseni, reduced the proportion of leaf damaged by these insects, and reduced the number of plants infested with aphids and Acidodis larvae.

Above- and below-ground net production in 40-year-old Douglas-fir stands on low and high productivity sites

1981 ◽  
Vol 11 (3) ◽  
pp. 599-605 ◽  
Author(s):  
Michael R. Keyes ◽  
Charles C. Grier
Keyword(s):  
Fine Roots ◽  
Dry Matter ◽  
Net Primary Production ◽  
Douglas Fir ◽  
Dry Matter Production ◽  
Net Production ◽  
High Productivity ◽  
Matter Production ◽  
Below Ground ◽  
Productivity Potential

Above- and below-ground net primary production was estimated for 40-year-old Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stands growing on sites with apparently large differences in productivity potential. Aboveground net production was estimated from direct measurements of tree growth; belowground productivity was derived from data obtained by sorting live and dead roots from soil cores used in combination with measurements of root growth on observation windows.Aboveground net production was 13.7 t•ha−1 on the high productivity site and 7.3 t•ha−1 on the low productivity site. Belowground dry matter production on the high productivity site was 4.1 t•ha−1 compared with 8.1 t•ha−1 for the poorer site. On the more productive site, 8% of total stand dry matter production was in fine roots in contrast to over 36% on the poorer site. The difference in total net production (aboveground plus belowground) between the two sites was small (2.4 t•ha−1). Apparent differences in aboveground productivity may, to a large extent, result from the need for a greater investment in the fine roots on harsher sites.

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