Fractal analysis for root growth of plant seedlings under doubled CO2 concentration

As opposed to direct sowing, production of seedlings of vegetable crops for transplanting is commonly practiced by vegetable growers. This study was undertaken to determine the effects of humic acid on the growth and the macro and micro nutrients contents in tomato (Lycopersicon esculentum) and eggplant (Solanum melongena var. esculentum) seedlings under greenhouse conditions. Different levels of humic acid (50, 100, 150, 200 ml l-1) were applied to growing media (peat) after transplanting of examined seedlings of the species every ten days by the time of planting. The highest growth rate for leaf stem and root growth were obtained at 50 and 100 ml l-1 HA and 50, 100, 150 ml l-1 HA for tomato and eggplant seedlings., respectively as compared to the control. The highest content of macro and micronu trient contents were obtained at 100 ml l-1 HA and 200 ml l-1 HA for tomato and egg plant seedlings, respectively as compared to the control.

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Effects of elevated CO2 on development and morphology of spring wheat grown in cooled and non-cooled open-top chambers

Functional Plant Biology ◽

10.1071/pp98016 ◽

1998 ◽

Vol 25 (5) ◽

pp. 617 ◽

Cited By ~ 11

Author(s):

M. van Oijen ◽

A.H.C.M. Schapendonk ◽

M.J.H. Jansen ◽

C.S. Pot ◽

J. van Kleef ◽

...

Keyword(s):

Elevated Co2 ◽

Spring Wheat ◽

Cooling System ◽

Co2 Concentration ◽

Triticum Aestivum L ◽

Ambient Conditions ◽

Morphological Response ◽

Open Top Chambers ◽

Temperature Interaction ◽

Doubled Co2 Concentration

Facilities for studying effects of elevated CO2 on crops affect the microclimate in the crop. Open-top chambers may increase temperature by 1–3˚C compared to ambient conditions. This paper describes a newly developed cooling system for open-top chambers. In 1995 and 1996, experiments were carried out to test the system and analyse the effects of temperature on crop phenological and morphological response to elevated CO2. Spring wheat (Triticum aestivum L. cv. Minaret) was subjected to ambient and doubled CO2 concentration in both cooled and non-cooled chambers. The cooling system reduced temperature by 1.6–2.4˚C, and this delayed maturity by 10 days. In contrast, elevated CO2 did not affect phenological development. Elevated CO2 reduced tiller density, green leaf number per tiller and specific leaf area, thereby reducing the capacity for light interception of the crop. Crop height growth before anthesis mainly responded to temperature, but after anthesis it was only affected by CO2, indicating a shift from sink- to source-limited growth. For none of the parameters studied, a significant statistical interaction of CO2 and temperature was found. The cooling system proved effective. Atemperature difference of about 2˚C affected crop development and morphology more strongly than CO2 doubling. However, the absence of CO2-temperature interaction suggests that CO2 effects may validly be investigated even without a cooling system.

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Jack pine becomes more vulnerable to cavitation with increasing latitudes under doubled CO2 concentration

Botany ◽

10.1139/cjb-2017-0142 ◽

2018 ◽

Vol 96 (2) ◽

pp. 111-119 ◽

Cited By ~ 2

Author(s):

Md. Shah Newaz ◽

Qing-Lai Dang ◽

Rongzhou Man

Keyword(s):

Soil Moisture ◽

Hydraulic Conductivity ◽

Pinus Banksiana ◽

Carbon Dioxide Concentration ◽

Field Capacity ◽

Co2 Concentration ◽

Jack Pine ◽

Photoperiod Regime ◽

Seed Origin ◽

Doubled Co2 Concentration

Trees may migrate northward in response to climate change and become exposed to new photoperiod and soil moisture regimes. This study assessed the impacts of photoperiod and its interaction with soil moisture and carbon dioxide concentration ([CO2]) on the hydraulic conductivity in jack pine (Pinus banksiana Lamb.) and its vulnerability to xylem embolism. Seedlings were exposed to 400 vs. 950 μmol·mol−1 [CO2], 60%–70% vs. 30%–40% (of field capacity) soil moisture, and photoperiods of seed origin and 5° and 10° north of seed origin in greenhouses. Cavitation vulnerability curves were measured for determining the xylem pressure at which 50% hydraulic conductivity was lost (ΨPLC50). It was found that elevated [CO2] significantly increased hydraulic conductivity, whereas low soil moisture decreased it. Under elevated [CO2], the xylem became progressively more vulnerable to embolism with changes in photoperiod regime from the seed origin to 10° north of the seed origin, as indicated by the progressively less negative ΨPLC50. However, no such a trend was detected under the ambient [CO2]. The results suggest that the species may become less resistant to drought as the atmospheric [CO2] increases, hindering the northward migration or seed transfers. Even within its current natural distribution range, trees near its northern boundary of the range may be more vulnerable to embolism as the atmospheric [CO2] increases even without any change in moisture conditions.

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Effects of Cenococcum Geophilum on the Growth of Seedlings Of Ostryopsis Davidiana Dence. And Pinus Tabuleaformis Carr.

Bangladesh Journal of Botany ◽

10.3329/bjb.v50i3.55848 ◽

2021 ◽

Vol 50 (3) ◽

pp. 679-683

Author(s):

Hui Li ◽

Qingzhi Yao ◽

Ying Tie ◽

Huiying Zhao

Keyword(s):

Root Growth ◽

Host Plant ◽

Host Plants ◽

Pinus Tabulaeformis ◽

Infection Rates ◽

Cenococcum Geophilum ◽

Different Strains ◽

Plant Seedlings ◽

Growth Of Seedlings

The affinity and promoting ability of the Cenococcum geophilum strains (CgSO1, CgSB2, CgO5, SPOP2 and Cg5 #) to Ostryopsis davidiana and Pinus tabulaeformis were studied. The results showed that the tested strains formed ectomycorrhizae（ECM）with O. davidiana except the Cg5 # strain and the infection rates were 40-50%. CgSO1 and CgSPOP2 formed ECM with P. tabulaeformis and the infection rates were 10.3 and 12.4%, respectively. C. geophilum can promote the growth of the two host plant seedlings, especially for root growth. Results proved that the affinity of different strains to host plants and the affinity of the same strain to different host plants are different. Bangladesh J. Bot. 50(3): 679-683, 2021 (September)

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