Above-Ground Dry Matter Production in Three Stands of Trembling Aspen

1972 ◽  
Vol 2 (1) ◽  
pp. 27-33 ◽  
Author(s):  
D. F. W. Pollard

Above-ground biomass, annual production, and leaf area index (LAI) were estimated for several years in aspen stands aged 6, 15, and 52 years old in 1968. Based on regressions of dry weight on stem diameter, biomass (stems and branches) estimates for 1968 were 21 500 kg ha−1 in the juvenile stand, 51 200 kg ha−1 in the intermediate stand, and 91 800 kg ha−1 in the mature stand. Net annual above-ground production (stems and branches) for these stands in 1968 was 6900, 7000, and 1340 kg ha−1 respectively. In 1969, foliage amounted to 2600, 2600, and 1500 kg ha−1, providing LAI of 2.4, 2.9, and 1.6 for the stands. Net assimilation rates were roughly 20, 17, and 9 g m−2 week−1.Aspen stands regenerated as suckers may attain maximum annual production within a few years, coincident with the development of maximum LAI.

1984 ◽  
Vol 20 (2) ◽  
pp. 161-170
Author(s):  
D. Boobathi Babu ◽  
S. P. Singh

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.


1994 ◽  
Vol 51 (3) ◽  
pp. 430-435 ◽  
Author(s):  
S.S.S. Nogueira ◽  
V. Nagai ◽  
N.R. Braga ◽  
M. Do C.S.S. Novo ◽  
M.B.P. Camargo

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.


Científica ◽  
2020 ◽  
Vol 48 (2) ◽  
pp. 85
Author(s):  
Wellington Mezzomo ◽  
Marcia Xavier Peiter ◽  
Adroaldo Dias Robaina ◽  
Jardel Henrique Kirchner ◽  
Rogério Ricalde Torres ◽  
...  

1984 ◽  
Vol 20 (2) ◽  
pp. 161-170 ◽  
Author(s):  
D. Boobathi Babu ◽  
S. P. Singh

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.


1980 ◽  
Vol 31 (4) ◽  
pp. 673 ◽  
Author(s):  
MM Ludlow ◽  
DA Charles-Edwards

Dry weight, leaf area, light interception and canopy photosynthesis were measured during 3- or 5-week regrowth periods of Setaria anceps/Desmodium intortum swards cut to 7.5 or 15 cm. Dry matter production during the experiment and over the growing season increased with cutting height and with interval between defoliations, but the proportion of grass to legume was unaffected. These effects of defoliation on dry matter production were similar to those estimated for integrated canopy photosynthesis from measured light interception and calculated leaf photosynthetic characteristics. Height and frequency of defoliation had no effect on canopy extinction coefficient for light, nor on the leaf photosynthetic characteristics, except for the first 1-2 weeks after defoliation when leaf photosynthetic rates appeared to be depressed. The main effects of height and frequency of defoliation on dry matter production were through their effects on leaf area index and light interception.


2020 ◽  
Vol 21 (supplement 1) ◽  
Author(s):  
T. Srinithan ◽  
K. Arivukkarasu Arivukkarasu ◽  
P. Sivasakthivelan ◽  
R. Rex Immanuel

A field experiment was conducted during Kuruvai season at the Experimental Farm, Department of Agronomy, Annamalai University to evaluate the performance of early post emergence application of herbicides on weed control in transplanted rice. The experiment was carried out in a Randomized Block Design with eight treatments and three replications. All the imposed treatments significantly influenced the weed parameters and crop parameters in rice. The experimental results revealed that, hand weeding twice at 20 and 40 DAT recorded the lowest total weed count (13.74), highest weed control efficiency (WCE) (92.79 per cent), highest plant height (85.76 cm), higher leaf area index (4.28), higher crop dry matter production (7689 kg ha-1 )and highest nutrient uptake by rice crop (134.79, 33.17, 99.41 kg of N, P2O5 , K2O ha-1, respectively) which was statistically on par with application of penoxsulam + cyhalofop butyl@135 g ha-1 (premix)(15 DAT) that recorded the total weed count (16.74), weed control efficiency (91.21 per cent), plant height (85.03cm), leaf area index (4.19), dry matter production (7567 kg ha-1), crop nutrient uptake (132.37 , 32.48, 97.25 kg of N, P2O5 , K2O ha-1, respectively). Highest total weed count, with lowest plant height, leaf area index, crop dry matter production and crop nutrient uptake were recorded with unweeded control.


Author(s):  
B. Sreedevi ◽  
Aarti Singh ◽  
M. Tejaswini

Aerobic rice is a new way of cultivating rice that requires less water than lowland rice. A field experiment was conducted during the kharif season of 2015 to evaluate the effects of nutrient management with Biofertilizers on growth and yield attributes, yield, nutrient uptake and economics different rice cultivars. The experiment was laid out split plot design with four replications. Main plot treatments consisted of two cultivars viz., whereas, sub plot treatments comprised of nutrient management practices namely, N1-125% RDF, N2-125% RDF + Biofertilizers, N3 -100% RDF, N4 -100% RDF + Biofertilizers, N5-75% RDF, N6-75% RDF + Biofertilizers. The source of biofertiliser was a combination of Azospirillum, Phosphorus Solubilizing Bacteria and Potassium Solubilizer applied @ 5 kg/ha-1. Crop dry matter production (2582.3 g/m2), root dry matter production (910.1 g/m2), tillers/m2 (566), leaf area index (4.54), panicles/m2 (535), panicle length (23.81), panicle weight (4.56) and test weight (25.3) was higher in PA 6444 compared to DRR Dhan 44. Higher uptake of nutrients was also observed in PA 6444. Rice fertilized with 125% RDF + Biofertilizers (N2) produced higher crop (2901.6 g/m2) and root dry matter production (1028.1 g/m2), tillers/m2 (561) and leaf area index (5.19). This treatment also recorded higher yield attributes and grain yield (3.55 t/ha). With respect to nutrient uptake, application of 125% RDF + Biofertilizers (N2) recorded      higher N, P and K uptake by grain and straw and higher profitability (1.57) than other nutrient combinations.


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