Relative fitness of s-triazine susceptible and resistant biotypes of Chenopodium album

The relative fitness of s-triazine susceptible and resistant biotypes of Chenopodium album from Quebec were compared in three greenhouse experiments. Under non-competitive conditions, there was no difference in dry matter production between biotypes, but the resistant biotype allocated less dry matter to seed production and produced fewer seeds than the susceptible. Results from de Wit replacement series performed at 400 plants m2 indicated that the relative proportion of biomass and seeds produced by the susceptible biotype was always greater than the proportion of susceptible plants present in any given treatment. The effects of root, shoot, and full (root + shoot) competition were compared between and within biotypes at planting densities of 400,666,934,1200, and 1466 seedlings m-2. Biotype had the most pronounced effect on all variables among the factors studied. The susceptible seedlings were taller, had a greater leaf area index (LAI), more leaves, and greater leaf, stem, and above-ground dry matter yields than the resistant seedlings, regardless of the planting density or the mode of competition. The fitness of the susceptible biotype was greatest when both biotypes were competing for light. The effects of shoot competition for light on yield, LAI, leaf numbers, and seedling height, were as important as those of full competition. The effects of root competition, although significant, were not nearly as important. The data indicate that if s-triazines are no longer used in a field, the C. album population will revert naturally to susceptibility because of the superior fitness of the susceptible biotype.

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Effects of Planting Density on Water Use and Productivity of Pearl Millet (Pennisetum Typhoides) Grown on Stored Water. II. Water Use, Light Interception and Dry Matter Production

Experimental Agriculture ◽

10.1017/s0014479700017786 ◽

1984 ◽

Vol 20 (3) ◽

pp. 215-224 ◽

Cited By ~ 30

Author(s):

S. N. Azam-Ali ◽

P. J. Gregory ◽

J. L. Monteith

Keyword(s):

Pearl Millet ◽

Water Use ◽

Dry Matter ◽

Dry Weight ◽

Planting Density ◽

Area Index ◽

Wide Spacing ◽

Neutron Probe ◽

Matter Production ◽

Intercepted Radiation

SUMMARYPearl millet was grown on stored water at Niamey, Niger, using three row spacings. Water extraction based on neutron probe readings was compared with crop transpiration using a porometer and allied measurements. Between 23 and 52 days after sowing, plants at the narrow and medium spacings used about 77 and 100 mm of water, respectively, and those at the wide spacing used between 59 and 75 mm. Estimates of seasonal crop evaporation from leaf resistances and from the green leaf area index (GLAI) of the crops were 103, 130 and 123 mm for the narrow, medium and wide spacings, respectively. The water use per unit of dry weight produced was similar for both narrow and medium spacings but water was used more efficiently in the wide spacing. Dry weight increased in proportion to intercepted radiation with the same efficiency (1·3 g MJ−1) irrespective of spacing.

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Prediction of the influence of water, sowing date and planting density on dry matter production of wheat

Australian Journal of Agricultural Research ◽

10.1071/ar9800001 ◽

1980 ◽

Vol 31 (1) ◽

pp. 1 ◽

Cited By ~ 8

Author(s):

RJ Hanks ◽

DW Puckridge

Keyword(s):

Dry Matter ◽

South Australia ◽

Sowing Date ◽

Planting Density ◽

Dry Matter Production ◽

Balance Model ◽

Area Index ◽

Matter Production ◽

Influence Of Water ◽

Good Agreement

A water balance model was used to calculate dry matter yields for wheat. The prediction used initial soil water, irrigation, rainfall and pan evaporation as inputs. Leaf area index (LAI) was estimated by an empirical equation and changes in LAI were determined by the ratio of predicted to potential transpiration and relative density. Time of sowing influenced time of maximum LAI. Dry matter production was calculated from equations relating LAI and photosynthesis. The model was tested with data from wheat crops in South Australia which had been grown with large differences in water supply, planting density and sowing date between seasons. There was good agreement between predicted and measured production.

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Effects of Planting Density on Leaf Area and Productivity of Two Maize Cultivars in Nigeria

Experimental Agriculture ◽

10.1017/s0014479700013478 ◽

1982 ◽

Vol 18 (1) ◽

pp. 93-100 ◽

Cited By ~ 8

Author(s):

S. U. Remison ◽

E. O. Lucas

Keyword(s):

Grain Yield ◽

Leaf Area Index ◽

Leaf Area ◽

Dry Matter ◽

Plant Population ◽

Planting Density ◽

Dry Matter Yield ◽

Area Index ◽

Positive Correlation ◽

Maize Cultivars

SUMMARYTwo maize cvs, FARZ 23 and FARZ 25, were grown at three densities (37,000, 53,000 and 80,000 plants/ha) in 1979 and 1980. Leaf area index (LAI) increased with increase in plant population and was at a maximum at mid-silk. Grain yield was highest at 53,000 plants/ha. There was no relation between LAI and grain yield but there was a positive correlation between LAI and total dry matter yield.

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Studies on Transpiration Suppressants on Spring Sorghum in North-Western India in Relation to Soil Moisture Regimes. II. Effect on Growth and Nutrient Uptake

Experimental Agriculture ◽

10.1017/s0014479700003276 ◽

1984 ◽

Vol 20 (2) ◽

pp. 161-170

Author(s):

D. Boobathi Babu ◽

S. P. Singh

Keyword(s):

Soil Moisture ◽

Leaf Area Index ◽

Nutrient Uptake ◽

Leaf Area ◽

Dry Matter ◽

Western India ◽

Area Index ◽

Matter Production ◽

Moisture Regimes ◽

North Western

SUMMARYThe effects of irrigation and spraying of transpiration suppressants on growth and nutrient uptake by spring sorghum (CSH 6) have been investigated. Crop growth, measured by plant-height, leaf area index and dry matter production, and uptake of N, P and K increased with more frequent irrigation and in response to the spraying of transpiration suppressants. Foliar applications of atrazine at 200 g ha−1 and CCC at 300 ml ha−1 proved to be the best in this NW Indian location.

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Comparative Yield, Fiber Quality and Dry Matter Production of Cotton Planted at Various Densities under Equidistant Row Arrangement

Agronomy ◽

10.3390/agronomy10020232 ◽

2020 ◽

Vol 10 (2) ◽

pp. 232

Author(s):

Nangial Khan ◽

Fangfang Xing ◽

Lu Feng ◽

Zhanbiao Wang ◽

Minghua Xin ◽

...

Keyword(s):

Leaf Area Index ◽

Leaf Area ◽

Dry Matter ◽

Plant Density ◽

Fiber Quality ◽

Biomass Accumulation ◽

Lint Yield ◽

Planting Density ◽

Area Index ◽

High Plant Density

The number of cotton plants grown per unit area has recently gained attention due to technology expense, high input, and seed cost. Yield consistency across a series of plant populations is an attractive cost-saving option. Field experiments were conducted to compare biomass accumulation, fiber quality, leaf area index, yield and yield components of cotton planted at various densities (D1, 1.5; D2, 3.3; D3, 5.1; D4, 6.9; D5, 8.7; and D6, 10.5 plants m−2). High planting density (D5) produced 21% and 28% more lint yield as compared to low planting density (D1) during both years, respectively. The highest seed cotton yield (4662 kg/ha) and lint yield (1763 kg/ha) were produced by high plant density (D5) while the further increase in the plant population (D6) decreased the yield. The increase in yield of D5 was due to more biomass accumulation in reproductive organs as compared to other treatments. The highest average (19.2 VA gm m−2 d−1) and maximum (21.8 VM gm m−2 d−1) rates of biomass were accumulated in reproductive structures. High boll load per leaf area and leaf area index were observed in high planting density as compared to low, while high dry matter partitioning was recorded in the lowest planting density as compared to other treatments. Plants with low density had 5% greater fiber length as compared to the highest plant density, while the fiber strength and micronaire value were 10% and 15% greater than the lowest plant density. Conclusively, plant density of 8.7 plants m−2 is a promising option for enhanced yield, biomass, and uniform fiber quality of cotton.

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EFFECT OF PLANTING DENSITY ON DRY-MATTER PRODUCTION AND EVAPOTRANSPIRATION OF TULIPS

Acta Horticulturae ◽

10.17660/actahortic.1975.47.55 ◽

1975 ◽

pp. 397-398 ◽

Cited By ~ 1

Author(s):

G.G.M. van der Velk

Keyword(s):

Dry Matter ◽

Planting Density ◽

Dry Matter Production ◽

Matter Production

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Growth analysis of chickpea (Cicer arietinum L.)

Scientia Agricola ◽

10.1590/s0103-90161994000300008 ◽

1994 ◽

Vol 51 (3) ◽

pp. 430-435 ◽

Cited By ~ 4

Author(s):

S.S.S. Nogueira ◽

V. Nagai ◽

N.R. Braga ◽

M. Do C.S.S. Novo ◽

M.B.P. Camargo

Keyword(s):

Leaf Area Index ◽

Leaf Area ◽

Dry Matter ◽

Growth Analysis ◽

Climatic Conditions ◽

Area Index ◽

Experimental Station ◽

Matter Production ◽

Winter Crop ◽

Quadratic Models

An experiment to study the growing pattern of a chickpea variety, IAC-Marrocos, was carried out at the Monte Alegre Experimental Station, SP, during 1987 and 1988. The dry matter production of all parts of the plant, as well the leaf area index, were weekly evaluated. Exponential quadratic models of regression were adjusted to total dry matter, leaf dry matter and leaf area index, and a linear model to dry matter of grain. Based on the growth analysis it was concluded that the chickpea is a rustic eatable plant that can be recommended as an alternative winter crop for similar climatic conditions as those of the experiment.

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A comparison of barley cultivars with different leaf inclinations

Australian Journal of Agricultural Research ◽

10.1071/ar9720945 ◽

1972 ◽

Vol 23 (6) ◽

pp. 945 ◽

Cited By ~ 41

Author(s):

JF Angus ◽

R Jones ◽

JH Wilson

Keyword(s):

Dry Matter ◽

Canopy Structure ◽

The Other ◽

Dry Matter Production ◽

Visible Radiation ◽

Area Index ◽

Assimilation Chamber ◽

Barley Cultivars ◽

Matter Production ◽

Erect Leaf

Under conditions of adequate moisture an erect-leaf barley cultivar, Lenta, responded to an increase in density (resulting from doubling of the sowing rate) with increases in dry matter production and in grain yield, whereas the cultivar Research, which has long lax leaves, responded with decreases in dry matter production and yield. In a study of canopy structure and its effects on light interception and utilization, it was found that in Research, with a leaf area index (LAI) of 6.1, the leaves were concentrated near the canopy surface and a relatively small proportion of the above-crop light penetrated through this layer. The net crop photosynthesis of this canopy (measured in a field assimilation chamber) was 3.8 g CO2/m2.hr when visible radiation was 313 W/m2. With Lenta (LAI 7.0) on the other hand, leaves were concentrated in the middle layers of the canopy and the light was more evenly distributed throughout the canopy. The net crop photosynthesis with the same radiation as for Research was 4.3 g CO2/m2.hr. The relative rates of photosynthesis at various levels in the canopies were determined by introducing 14CO2 into the assimilation chambers enclosing the cultivars and observing where the 14C was fixed. With Research most of it was localized near the canopy surface while with Lenta most of it was near the centre of the canopy. Of the 14CO2 taken up, 7 % was fixed in the leaf sheaths of Research and 12% in those of Lenta.

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

The Journal of Agricultural Science ◽

10.1017/s0021859600024151 ◽

1969 ◽

Vol 73 (1) ◽

pp. 75-86 ◽

Cited By ~ 23

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.

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