Effect of temperature on dry matter production of Douglas-fir seedlings during bud dormancy

1969 ◽  
Vol 47 (7) ◽  
pp. 1143-1146 ◽  
Author(s):  
Holger Brix
Keyword(s):  
Temperature Effect ◽  
Dry Matter ◽  
Growth Period ◽  
Dry Weight ◽  
Douglas Fir ◽  
Bud Dormancy ◽  
Dry Matter Production ◽  
Effect Of Temperature ◽  
Leaf Production ◽  
Matter Production

Bud dormancy was induced in Douglas-fir seedlings 90 days after seed germination. Dry matter production of bud-dormant plants was determined for a 7-week growth period at five controlled temperatures from 2 to 24 °C. There was no significant temperature effect between 7 and 24 °C on total dry matter production, which at 2 °C was reduced. Dry weight of the root was affected more by temperature than that of the plant top. A pronounced temperature effect on dry matter production was found previously between 13 and 18 °C for plants in the stage of leaf production. This did not occur for bud-dormant plants because temperature effect on leaf production was not present. Net assimilation rates during bud dormancy were generally lower than during the stage of leaf production, especially at low temperature. This may have been caused by a reduced "sink" for use of photosynthates during bud dormancy.

Seedling growth of summer-dormant and non-dormant ryegrasses in relation to temperature

1969 ◽  
Vol 20 (3) ◽  
pp. 417 ◽  
Author(s):  
JH Silsbury
Keyword(s):  
Dry Matter ◽  
Growth Curves ◽  
Dry Weight ◽  
Detailed Examination ◽  
Dry Matter Production ◽  
Controlled Environment ◽  
Lolium Rigidum ◽  
Relative Growth ◽  
Lolium Perenne L ◽  
Matter Production

Lolium rigidum Gaud. and a summer-dormant and a non-dormant form of Lolium perenne L. were grown as seedling plants for 32 days in controlled environment cabinets at constant temperatures of either 10, 20, or 30°C and in all cases with a 16-hr photoperiod at a light intensity of 3600 lm ft-2. Sampling at 4-day intervals permitted the detailed examination of dry matter growth curves. Differences in total dry matter production were related to initial differences in seedling dry weight, and the general responses to temperature were similar for each ryegrass. Total dry matter production was greatest at 20°C and lowest at 10°. A temperature of 30° did not induce dormancy in the summer-dormant ryegrass but did depress growth. Relative growth rate fell with time at each temperature.

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.

The growth of lodgepole pine seedlings raised under clear polythene cloches at five seedbed densities

1980 ◽  
Vol 10 (3) ◽  
pp. 426-428
Author(s):  
S. Thompson
Keyword(s):  
Plant Height ◽  
Dry Matter ◽  
Shoot Growth ◽  
Lodgepole Pine ◽  
Unit Length ◽  
Dry Weight ◽  
Dry Matter Production ◽  
Matter Production ◽  
Pine Seedlings ◽  
Foliage Weight

The components of shoot growth and dry matter production in 1 + 0 lodgepole pine (Pinuscontorta Dougl. ex Loud. spp. contorta) seedlings raised under clear polythene cloches for 12 weeks at five seedbed densities (180–720 plants/m2) were studied. The greater plant height found at the highest seedbed density was the result of increased stem unit length, not increased number of stem units. The increase in plant dry weight as seedbed density decreased was largely due to greater dry weight of roots, branchwood, and branch foliage, and not to increases in stemwood and stem foliage weight. Seedbed densities of less than 460 seedlings/m2 are required to produce yields of suitably sturdy seedlings in excess of 50% of the crop.

A winter wheat crop simulation model without water or nutrient limitations

1984 ◽  
Vol 102 (2) ◽  
pp. 371-382 ◽  
Author(s):  
A. H. Weir ◽  
P. L. Bragg ◽  
J. R. Porter ◽  
J. H. Rayner
Keyword(s):  
Winter Wheat ◽  
Simulation Model ◽  
Grain Growth ◽  
Dry Matter ◽  
Growth Period ◽  
Dry Matter Production ◽  
Wheat Crop ◽  
Daily Maximum ◽  
Computer Simulation Model ◽  
Matter Production

SummaryA whole crop computer simulation model of winter wheat has been written in FORTRAN and used to simulate the growth of September- and October-sown crops of Hustler wheat at Rothamsted for the years 1978–9, 1979–80 and 1980–1. Results of the simulations, which are for crops with adequate water and nutrients, are compared with observations from experiments at Rothamsted. The model uses daily maximum and minimum temperatures and daylength to calculate the dates of emergence, double ridge, anthesis and maturity of the crops and the growth and senescence of tillers and leaves. In the simulations, the canopy intercepts daily radiation and produces dry matter that is partitioned between roots, shoots, leaves, ears and grain. Partial simulations, using observed LAI values, produced dry matter in close agreement with observations of late-sown crops, but consistently overestimated the total dry-matter production of the early-sown crops. Full simulation described satisfactorily the average difference in dry-matter production to be expected with changes in time of sowing, but did not give as close correspondence for individual crops. A grain growth submodel, that linked maximum grain weight to average temperatures during the grain growth period, correctly simulated the observed growth of individual grains in the 1981 crop. The benefits to be obtained by combining whole crop modelling with detailed crop observations are discussed.

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.

The growth and performance of cotton in a desert environment: II. Dry matter production

1969 ◽  
Vol 73 (1) ◽  
pp. 75-86 ◽  
Author(s):  
A. B. Hearn
Keyword(s):  
Growth Rate ◽  
Dry Matter ◽  
Initial Period ◽  
Dry Weight ◽  
Dry Matter Production ◽  
Area Index ◽  
Vegetative Phase ◽  
Matter Production ◽  
Sink Size ◽  
And Performance

SUMMARYVariety, water and spacing were treatments in two experiments with cotton in 1963 and 1964 in which fruiting points, flowers and bolls were counted and the dry weights and leaf areas of plants were measured at intervals during the season.Until leaf-area index, L, started to decrease, the equation described how dry weight, W, changed. The equation gave smoothed estimates of crop growth rate, C, which were consistent with estimates of photosynthesis made with de Wit's (1965) model. The relationship between G and L conformed to , derived from Beer's Law, rather than C = aL — bL2 derived from the linear regression of E on L. When L > 3 the crop appeared to use most of the available light, so that C approached a maximum. Treatments initially affected dry-matter production through the numbers and types of branches and nodes, which in turn affected the sinks available and thus the proportion of dry matter reinvested in new leaf. This initial period, when growth was simple to describe in conventional terms, was denned as the vegetative phase of growth.The start of the reproductive phase of growth overlapped the vegetative phase. The change from one to the other was completed when the rate of dry weight increase of the bolls, CB, equalled C. This indicated that the sink formed by the bolls had increased sufficiently in size to use all the assimilates available for growth. Sink size increased as the crop flowered and was estimated from the product of the number of bolls and the growth rate of a single boll.When CB equalled C, bolls were shed which prevented the size of the sink to increase beyond the ability of the plant to supply it with assimilates. This agrees with Mason's nutritional theory of boll shedding. Because of the crop's morphology and because age decreased the photosynthesis of the crop, the size of the sink inevitably increased out of phase with the supply of assimilates. The extent to which this was so determined when CB equalled C. It is postulated that environment, genotype and agronomic practice affect yield according to whether they increase or decrease the extent to which the sink size and the supply of assimilates are out of phase.

scholarly journals The effect of potash fertilization on dry matter production of permanent pasture throughout the season.

1958 ◽  
Vol 6 (2) ◽  
pp. 124-130
Author(s):  
P. De Vries ◽  
C.T. De Wit
Keyword(s):  
Sandy Soil ◽  
Dry Matter ◽  
Dry Matter Production ◽  
Effect Of Temperature ◽  
K Uptake ◽  
Permanent Pasture ◽  
Matter Production ◽  
Low K ◽  
K Response

On sandy soil of low K availability, permanent pasture cut 5 times during the year received up to 200 kg/ha K2O as 40% KC1 before or after one of the cuts. The effect of K fertilizing in autumn depended largely on K withdrawal with previous cuts. K uptake was not determined by growth. Except for the first cut K uptake was greater than that needed for reasonable growth. No effect of temperature on K response was found. The best treatment was 200 kg/ha K2O applied in spring. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Modelling growth and nitrogen balance of barley under ambient and future conditions

1996 ◽  
Vol 5 (3) ◽  
pp. 299-310 ◽  
Author(s):  
Jouko Kleemola ◽  
Tuomo Karvonen
Keyword(s):  
Soil Temperature ◽  
Dry Matter ◽  
Spring Barley ◽  
Dry Weight ◽  
N Fertilization ◽  
Snow Accumulation ◽  
Dry Matter Production ◽  
Hordeum Vulgare L ◽  
Crop Species ◽  
Matter Production

According to current scenarios, atmospheric CO2 -concentration ([CO2]) and average air temperature will rise in the future. The predicted longer growing season in Finland would imply that more productive cultivars and even new crop species could be grown. Moreover, higher [CO2] is also likely to increase dry matter production of crops. This study analyzed the growth of spring barley (Hordeum vulgare L.) under ambient and suggested future conditions, and its response to N fertilization. Model simulations of soil temperature and of snow accumulation and melting were also studied. The calibration and validation results showed that the model performed well in simulating snow dynamics, soil temperature, the growth of barley, and the response of crop growth to N fertilization under present conditions. According to the simulation runs, if a cultivar was adapted to the length of the growing period, the increase in dry matter production was 23% in a low estimate scenario of climate change, and 56% in a high estimate scenario under a high level of nitrogen fertilization. The simulation study showed that the shoot dry weight increased by 43%, on average, under high N fertilization (150-200 kg N/ha), but by less (20%) under a low level of N (25-50 kg N/ha) when the conditions under a central scenario for the year 2050 were compared with the present ones.

scholarly journals Nutrient uptake and dry matter yield in the ‘Gunung’ yam (Dioscorea alata) grown on an Ultisol without vine support

1969 ◽  
Vol 79 (3-4) ◽  
pp. 121-130
Author(s):  
Héber Irizarry ◽  
Ricardo Goenaga ◽  
Ulises Chardón
Keyword(s):  
Nutrient Uptake ◽  
Dry Matter ◽  
Dry Weight ◽  
Minor Element ◽  
Dry Matter Production ◽  
Fertilizer Treatment ◽  
Dioscorea Alata ◽  
Dry Matter Yield ◽  
Matter Production ◽  
A Minor

Two experiments were established 1 May through 1 December 1991 and 1992 to determine the monthly nutrient uptake and dry matter production of the 'Gunung' yam (Dioscorea alata) grown on an Ultisol. During the first year the plants were fertilized with 0; 667; 1,333; 2,000 and 2,667 kg/ha of a 15-5- 15-5 (N, P2O5, K2O and MgO) fertilizer supplemented with a minor element mixture. No fertilizer was applied the second year. Biomass harvests were conducted at 2, 3, 4, 5, 6 and 7 months after planting. At each harvest, the plants were dug-up and separated into leaf-laminas, vine and petioles, roots and tubers. Fresh and oven-dry weights of the plant components were determined and samples from each were analyzed for N, P, K, Ca and Mg. Regardless of the year, tuber dry matter yield was not significantly affected by the fertilizer treatment. Maximum nutrient uptakes were 214 kg/ha of N, 19 kg/ha of P, 223 kg/ha of K, 95 kg/ha of Ca and 9 kg/ha of Mg. Nitrogen, K and Ca uptake peaks occurred about five months after planting. Maximum dry matter production was 11,303 kg/ha, 8,672 kg/ha of which was tuber dry weight. The dry matter production peak occurred at the completion of the 7-month cropping cycle. The plants utilized 24.7 kg/ha of N, 2.2 kg/ha of P, 25.7 kg/ha of K, 11.0 kg/ha of Ca and 1.0 kg/ha of Mg, for every 1,000 kg/ha of edible dry matter produced.

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