Seed Size, the Only Factor Positively Affecting Direct Seeding Success in an Abandoned Field in Quebec, Canada

Annick St-Denis; Christian Messier; Daniel Kneeshaw

doi:10.3390/f4020500

Germination ecology of six species of Eucalyptus in shrink–swell vertosols: moisture, seed depth and seed size limit seedling emergence

Australian Journal of Botany ◽

10.1071/bt16155 ◽

2017 ◽

Vol 65 (1) ◽

pp. 22 ◽

Cited By ~ 4

Author(s):

Lorena Ruiz Talonia ◽

Nick Reid ◽

Caroline L. Gross ◽

R. D. B. Whalley

Keyword(s):

Soil Moisture ◽

Seed Size ◽

Seedling Emergence ◽

Seed Viability ◽

Direct Seeding ◽

Eucalyptus Species ◽

Sowing Depth ◽

South Wales ◽

Dry Conditions ◽

Moisture Conditions

We examined the potential of direct-seeding Eucalyptus species to revegetate the vertosol (‘cracking clay’) soils that characterise the floodplains of north-western New South Wales. We investigated the influence of sowing depth (0, 6, 12 and 20 mm) and three soil-moisture scenarios (dry, moist and flooded) on seedling emergence of seedlings of six species of Eucalyptus with a range of seed sizes (E. blakelyi, E. camaldulensis, E. melanophloia, E. melliodora, E. pilligaensis and E. populnea). We used cracking clay soil from the region in a glasshouse environment. Seedling emergence was low despite high seed viability and provision of optimum temperatures and soil moisture conditions. All six species exhibited greatest emergence when sown at 0–6-mm depth, with seed size being less important than moisture (except under dry conditions) and proximity to the surface. Species responded differently to the three watering treatments. Eucalyptus melanophloia exhibited greatest emergence in the ‘dry’ watering treatment. The floodplain species, E. camaldulensis, E pilliganesis and E. populnea, had the greatest emergence under flood conditions. Eucalyptus blakelyi and E. melliodora exhibited intermediate emergence in relation to all three soil-moisture regimes. Although the direct seeding of these species in vertosol soils in the region may be successful on occasion, windows of opportunity will be infrequent and the planting of seedling tubestock will be more reliable for revegetation.

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FloRunTM ‘331’ Peanut Variety

EDIS ◽

10.32473/edis-ag42-2019 ◽

2019 ◽

Vol 2019 (1) ◽

Author(s):

Barry L. Tillman

Keyword(s):

Seed Size ◽

Growth Habit ◽

Yield Potential ◽

High Yield ◽

University Of Florida ◽

High Oleic ◽

Central Stem ◽

Research And Education ◽

The University ◽

High Yield Potential

FloRunTM ‘331’ peanut variety was developed by the University of Florida, Institute of Food and Agricultural Sciences, North Florida Research and Education Center near Marianna, Florida. It was released in 2016 because it combines high yield potential with excellent disease tolerance. FloRunTM ‘331’ has a typical runner growth habit with a semi-prominent central stem and medium green foliage. It has medium runner seed size with high oleic oil chemistry.

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Dynamics of CO2 emission from chernozems under agricultural use

Agricultural science and practice ◽

10.15407/agrisp4.03.043 ◽

2017 ◽

Vol 4 (3) ◽

pp. 43-49

Author(s):

M. Miroshnychenko ◽

O. Siabruk

Keyword(s):

Carbon Dioxide ◽

Agricultural Practices ◽

Growing Season ◽

Warm Period ◽

Direct Seeding ◽

Soil Tillage ◽

Plant Residues ◽

Hydrothermal Conditions ◽

Organic Mineral ◽

Mineral System

Aim. The comparison of the effect of hydrothermal conditions and various agricultural practices on the emission of CO 2 from chernozems in the Left-Bank Forest-Steppe of Ukraine. Methods. The dynamics of the intensity of carbon dioxide emissions from chernozem calcic (typical chernozem – in Ukrainian classifi cation) was studied during the growing season of 2011–2012. The observations were based on two fi eld experiments with various methods of soil till- age (6–7 years from the beginning of the experiment) and fertilization systems (21–22 years from the beginning of the experiment). Particularly, plowing at 20–22 cm, disking at 10–12 cm, cultivation at 6–8 cm and direct seeding using Great Plains drill were studied among the soil tillage methods. Mineral system (N 45 P 50 K 45 ), organic system (manure 8 t/ha) and combined organic-mineral system (manure 8 t/ha + N 45 P 50 K 45 ) were studied among fertilization systems. The intensity of CO 2 fl ux was determined using the non-stationary respiratory chambers by the alkaline absorption method, with averaging of the results during the day and the frequency of once a month. Results. During the warm period, the emission of carbon dioxide from the soil changes dynamically depending on temperature and humidity. The maximum of emission coincides with the periods of warm summer showers in June-July, the minimum values are characteristic for the late autumn period. The total emission losses of carbon in chernozems over the vegetation period ranged from 480 to 910 kg/ha and varied depending on the methods of tillage ± (4.0–6.0) % and fertilization systems ± (3.8–7.1) %. The changes in the intensity of CO 2 emission from the soil under different methods of soil tillage are associated with hydrothermal regime and the depth of crop residues location. The biggest difference is observed im- mediately after tillage, but in the spring period the differences are only 12–25 %, and after drying of the top layer of soil become even less. Direct seeding technology provides the greatest emission of CO 2 from chernozem, which is fa- cilitated by better water regime and more complete mineralization of plant residues on the soil surface. Annual losses of carbon are the least under disking of soil at 10–12 cm. The changes in the intensity of CO 2 emission from the soil under different fertilization systems are associated with the involvement of the additional organic matter from plant residues and manure to the microbiological decomposition. The greatest emission was observed under the organic- mineral fertilization system, which increased the loss of carbon by 7–8 % in comparison with the mineral system in the unfavorable hydrothermal year and by 11–15 % in the more favorable year. These differences are observed mainly during the fi rst half of the growing season when there is a clear tendency to increase the intensity of soil respiration. Conclusions. The hydrothermal conditions of the warm period of the year are decisive in the formation of the CO 2 emission fl ow from chernozems. Due to the improvement of agricultural practices, emissions might be reduced but not more that by 15 % of natural factor contribution.

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