SUPERABSORBENT POLYMER-AMENDED MEDIA FOR CONTAINER-GROWN WOODY ORNAMENTAL CROPS

Rooted cuttings of Photinia X fraseri and Podocarpus macrophyllus were grown in Metro-mix 500 amended with 0.0, 0.25, 0.50, 0.75, or 1.0% (w/w) Stockosorb 300, a K-based superabsorbent polymer. All 3-liter containers were irrigated with 500 ml of 100, 200, 300, or 400 ppm 20N-8.7P-16.72K Peters fertilizer solution once every 3, 6, 9, or 12 days, respectively. In comparison with the unamended media, P. X fraseri had equal or better growth (shoot and root fresh and dry weights, increased height, and branch and leaf numbers) with 3, 6, and 9 day irrigation in all but the 1 % amended medium. Growth of P. macrophyllus was not noticeably affected by the polymer amendment. This is not unexpected since P. X fraseri is a broad-leaf plant while P. macrophyllus is a slow growing, narrow-leaf conifer. Nitrogen, P, and K tissue levels for Photinia and Podocarpus decreased for the 12 day irrigation treatment regardless of amendment rate. Except for Fe, which was highest at nine day irrigation intervals, micronutrients remained more or less constant in both species. The amended media had a greater water holding capacity at termination of the project (144 and 192 days for Photinia and Podocarpus, respectively) than at the start. Thus, K-based superabsorbents may be used successfully to reduce irrigation frequency.

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Zinc Uptake by Pelargonium × hortorum Grown in Shredded Tire Rubber-amended Media

HortScience ◽

10.21273/hortsci.32.3.485b ◽

1997 ◽

Vol 32 (3) ◽

pp. 485B-485

Author(s):

Mohammad Baqir ◽

Richard L. Harkess

Keyword(s):

Particle Size ◽

Experimental Design ◽

Bulk Density ◽

Tissue Analysis ◽

Rooted Cuttings ◽

Tire Rubber ◽

Air Space ◽

The Media ◽

Water Holding ◽

Slow Growing

On 2 Feb. 1996, rooted cuttings of Pelargonium × hortorum L. H. Bailey cvs. Tango and Blues were planted in 750-cm3 (14 cm in diameter) pots containing peatmoss mixed with shredded tire rubber (2–6.0 mm particle size) at 0%, 20%, 40%, 60%, or 80%. Plants were irrigated by hand, drip, or ebb-and-fl ood, and were arranged in a split-plot experimental design. A wetting agent (Aqua Gro 2000 L, Aquatrols Corporation, Cherry Hill, N.J.) was mixed at the rate of 6 ml per 3750 ml of water and 120 ml of solution was applied to each plant. Greenhouse studies indicated that geraniums could be grown successfully in media containing up to 20% shredded tire rubber by volume when irrigated by hand. Plants grown in media containing more than 20% rubber were observed to be slow-growing and chlorotic. Tissue analysis of the plants indicated significantly increased levels of zinc in plants grown in media containing high percentages of rubber. Geraniums grown in media containing 80% rubber and irrigated using ebb-and-fl ood benches had the significantly highest levels of foliar zinc. Media porosity, percent air space, and bulk density increased, while water holding capacity decreased with increasing amounts of shredded tire rubber added to the media.

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Growth of Container-grown Plants With and Without Azomite Soil Amendment

HortScience ◽

10.21273/hortsci.33.3.492c ◽

1998 ◽

Vol 33 (3) ◽

pp. 492c-492

Author(s):

Chris Ely ◽

Mark A. Hubbard

Keyword(s):

Plant Growth ◽

Physical Properties ◽

Bulk Density ◽

Soil Amendment ◽

Extended Period ◽

Mineral Elements ◽

Field Soil ◽

Rooted Cuttings ◽

Sodium Calcium ◽

Water Holding

Azomite is a mined, commercially available, hydrated sodium calcium aluminosiliclate soil amendment reported to act as a source of mineral elements. To determine its effect on plant growth, Dendranthema `Connie' rooted cuttings, Malus seedlings, and Citrus seedlings were grown in containers in one of two growing media: ProMix BX or ProMix BX with Azomite (1:1, v:v). Plant height was monitored weekly and after 6 weeks of growth, fresh and dry plant weights of roots and shoots were determined. There was no difference in any of the parameters measured as a result of the addition of Azomite. Any nutritional influence of the Azomite may only be evident in different conditions, e.g., field soil, or over an extended period of time. The Azomite altered the medium's physical properties and therefore bulk density and water-holding capacity of the Azomite were determined for consideration.

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Irrigation Scheduling with Soil Gas Diffusivity as a Decision Tool to Mitigate N2O Emissions from a Urine-Affected Pasture

Agriculture ◽

10.3390/agriculture11050443 ◽

2021 ◽

Vol 11 (5) ◽

pp. 443

Author(s):

Camille Rousset ◽

Timothy J. Clough ◽

Peter R. Grace ◽

David W. Rowlings ◽

Clemens Scheer

Keyword(s):

Irrigation Management ◽

Irrigation Treatment ◽

Irrigation Scheduling ◽

Soil Gas ◽

N2o Emissions ◽

Irrigation Frequency ◽

Water Demands ◽

Gas Diffusivity ◽

Matter Production ◽

Access To Water

Pastures require year-round access to water and in some locations rely on irrigation during dry periods. Currently, there is a dearth of knowledge about the potential for using irrigation to mitigate N2O emissions. This study aimed to mitigate N2O losses from intensely managed pastures by adjusting irrigation frequency using soil gas diffusivity (Dp/Do) thresholds. Two irrigation regimes were compared; a standard irrigation treatment based on farmer practice (15 mm applied every 3 days) versus an optimised irrigation treatment where irrigation was applied when soil Dp/Do was ≈0.033 (equivalent to 50% of plant available water). Cow urine was applied at a rate of 700 kg N ha−1 to simulate a ruminant urine deposition event. In addition to N2O fluxes, soil moisture content was monitored hourly, Dp/Do was modelled, and pasture dry matter production was measured. Standard irrigation practices resulted in higher (p = 0.09) cumulative N2O emissions than the optimised irrigation treatment. Pasture growth rates under treatments did not differ. Denitrification during re-wetting events (irrigation and rain) contributed to soil N2O emissions. These results warrant further modelling of irrigation management as a mitigation option for N2O emissions from pasture soils, based on Dp/Do thresholds, rainfall, plant water demands and evapotranspiration.

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Irrigation of greenhouse tomatoes grown in "Harrow" peat-bags

Canadian Journal of Plant Science ◽

10.4141/cjps91-136 ◽

1991 ◽

Vol 71 (3) ◽

pp. 947-949 ◽

Cited By ~ 2

Author(s):

Athanasios P. Papadopoulos ◽

Chin S. Tan

Keyword(s):

Lycopersicon Esculentum ◽

Key Words ◽

Environmental Conditions ◽

Total Yield ◽

Fruit Size ◽

Irrigation Frequency ◽

Marketable Yield ◽

Greenhouse Tomato ◽

Greenhouse Tomatoes ◽

Fertilizer Solution

Three spring and two fall crops of greenhouse tomato (Lycopersicon esculentum L. Mill; various cultivars) grown in "Harrow" peat bags were irrigated 1, 4, 8 or 16 times daily. All plants received the same volume of fertilizer solution which varied with time from 0.2 to 1.0 L plant−1 d−1 according to crop and environmental conditions. The results showed little or no effect of irrigation frequency on early or total yield, number of grade no. 1 fruit, or fruit size. Key words: Lycopersicon esculentum, marketable yield

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Rooting and Overwintering Stem Cuttings of Stewartia pseudocamellia Maxim. Relevant to Hormone, Media, and Temperature

HortScience ◽

10.21273/hortsci.43.7.2124 ◽

2008 ◽

Vol 43 (7) ◽

pp. 2124-2128 ◽

Cited By ~ 4

Author(s):

Ajay Nair ◽

Donglin Zhang ◽

John Smagula ◽

Dongyan Hu

Keyword(s):

Cold Treatment ◽

Stem Cuttings ◽

Optimum Conditions ◽

Rooted Cuttings ◽

Four Seasons ◽

Different Temperatures ◽

Overwintering Survival ◽

Garden Plant ◽

Water Holding

Stewartia pseudocamellia Maxim. (Japanese Stewartia), a member of Theaceae (tea family), is an excellent garden plant with ornamental features for all four seasons. Reproduction difficulty, however, limits its popularity. We conducted three experiments to ascertain the optimum conditions needed for rooting and subsequent overwintering of semihardwood Stewartia pseudocamellia cuttings. Cuttings were collected in July and prepared for rooting using two types of hormones (KIBA quick dip and Hormodin powder) and three media (Perlite + ProMix, Perlite + Perennial Mix, or Perlite + ProMix + Perennial Mix). Rooted cuttings were overwintered at four different temperatures. The best overwintering temperature was 5 °C, at which 65.6% of newly rooted cuttings survived. Temperatures lower than –12.2 °C were detrimental to the plants. Without cold treatment, only 21.9% of the rooted cuttings survived, which was three times lower than those that received 5 °C treatments. Plants rooted in Perlite + Perennial Mix had 61.8% overwintering survival, which is significantly higher than Perlite + ProMix. The quality of roots, indicated by total root length per cutting, was higher (104.3 cm) with Perlite + Perennial Mix, but not statistically significant. Cuttings treated with rooting hormones had higher rooting percentages (71.9% to 93.6%) as compared with the control (53%). For the same concentration (8000 mg·L−1), liquid (KIBA) and liquid + powder (KIBA + indole-3-butyric acid) rooting hormones resulted in better rooting percentages than powder (Hormodin) alone, although there was no statistical difference in rooting percentages among rooting hormone treatments. The best hormone for subsequent overwintering survival was the combination of quick dip (5000 mg·L−1 KIBA) and Hormodin #2 (0.3% a. i.; equivalent to 3000 mg·L−1). It resulted in 64.2% survival, significantly higher than for KIBA quick dip (8000 mg·L−1 a.i.) or Hormodin #3 (0.8% a. i.; equivalent to 8000 mg·L−1) alone. Our results suggest that reproduction (rooting and overwintering) of Stewartia was affected by many factors. We recommend rooting Stewartia in media that has good aeration and moderate water-holding capacity and overwintering them at ≈5 °C.

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The production and water extraction of lucerne and ryegrass under different irrigation frequencies on a shallow soil.

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.2014.76.2948 ◽

2014 ◽

Vol 76 ◽

pp. 221-228

Author(s):

A.J. Michel ◽

H.E. Brown ◽

E.I. Teixeira ◽

E.D. Meenken ◽

S. Maley ◽

...

Keyword(s):

Medicago Sativa ◽

Lolium Perenne ◽

Biomass Production ◽

Irrigation Treatment ◽

Water Extraction ◽

First Year ◽

Irrigation Frequency ◽

Shallow Soil ◽

Dry Conditions ◽

Medicago Sativa L

Abstract A field experiment was conducted on a shallow soil (low plant available water holding capacity) at Lincoln (Canterbury, New Zealand) to compare the biomass production of lucerne (Medicago sativa L.) and perennial ryegrass (Lolium perenne) under four different irrigation frequencies: (T1) replacing water use (WU) twice a week (replicating centre pivot rewetting frequencies); (T2) replacing WU fortnightly (replicating travelling irrigator); (T3) replacing WU every 3 weeks (replicating border dyke); (T4) nil irrigation (rain fed only). Soil water content was measured hourly at 0-30 cm depth and fortnightly at 0-150 cm depth. Plots were sown in March 2011 and defoliated on eight (ryegrass) and five to six (lucerne) occasions each season between September 2011 and May 2014. Annual biomass production during the first year was highest for ryegrass under each treatment because the lucerne crops were still establishing. During the second and third year of experimentation ryegrass yielded higher or similar to lucerne under the irrigated treatments (T1, T2 and T3). This was attributed to a decline in lucerne stands due to weed pressure. It is important to note that the ryegrass crop has received 250-700 kg N/ha per year depending on the irrigation treatment. Under dry conditions (T4) ryegrass yielded more than lucerne in both year 2 and 3. This result contrasts the literature and is attributed to the greater capacity of ryegrass to grow in cooler season and the stony sub-soil meaning lucerne received no summer yield advantage from its deep tap root. Key words: Medicago sativa L., Lolium perenne, biomass, water extraction, irrigation frequency

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Preparation and Characterization of Superabsorbent Polymers Based on Sawdust

Polymers ◽

10.3390/polym11111891 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1891 ◽

Cited By ~ 2

Author(s):

Mingchang Zhang ◽

Shaodi Zhang ◽

Zhuoran Chen ◽

Mingzhi Wang ◽

Jinzhen Cao ◽

...

Keyword(s):

Water Evaporation ◽

Superabsorbent Polymer ◽

X Ray Diffraction ◽

Synthesis Conditions ◽

Saturated Water ◽

Crosslinker Content ◽

Swelling Rate ◽

Forestry Industry ◽

Water Holding

Sawdust, a cheap by-product of the timber and forestry industry, was considered as a framework structure to prepare superabsorbent polymer with acrylic acid (AA) and acrylamide (AM), the synthetic monomers. The effects of initiator content, crosslinker content, AA content, AM content, degree of neutralization of AA, and reaction temperature on the swelling rate of superabsorbent polymer were investigated. The synthesized polymer was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Under optimal synthesis conditions, the results showed that the swelling rate of the polymer in deionized water and 0.9% NaCl solution reached 738.12 and 90.18 g/g, respectively. The polymer exhibits excellent swelling ability, thermal stability, and reusability. After the polymer was introduced into the samples (soil or coal), the water evaporation rate of the samples was significantly reduced, and the saturated water holding capacity and pore structure were also significantly improved.

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Raman spectroscopy to assess water holding capacity in muscle from fast and slow growing broilers

LWT ◽

10.1016/j.lwt.2014.01.028 ◽

2014 ◽

Vol 57 (2) ◽

pp. 696-700 ◽

Cited By ~ 4

Author(s):

Phodchanee Phongpa-Ngan ◽

Samuel E. Aggrey ◽

Jake H. Mulligan ◽

Louise Wicker

Keyword(s):

Raman Spectroscopy ◽

Water Holding Capacity ◽

Water Holding ◽

Slow Growing

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Water regime parameters in Chrysanthemum

TAURIDA HERALD OF THE AGRARIAN SCIENCES ◽

10.33952/2542-0720-2021-2-26-74-88 ◽

2020 ◽

Vol 2(26) ◽

pp. 74-88

Author(s):

S.G. Denisova ◽

◽

A.A. Reut ◽

Keyword(s):

Water Content ◽

Water Deficit ◽

Water Regime ◽

Water Holding Capacity ◽

Total Water Content ◽

Total Water ◽

Irrigation Frequency ◽

Resistant Varieties ◽

The Republic ◽

Water Holding

In introduction studies, it is urgent to determine how favorable the water balance of the species studied is under defined environmental conditions. The research aimed to scrutinize the water regime of Chrysanthemum × hortorum Bailey and select drought-resistant varieties to replenish the range of plants used for floriculture in the Republic of Bashkortostan on grey forest (Haplic Greyzems) loamy soil. The studies were conducted in 2018‒2020. Irrigation frequency – twice a week. After each watering, soil loosening was carried out. One week before sampling for analysis, we stopped watering flowers. Water regime indicators were analyzed according to the method of artificial wilting (V. N. Tarenkov et al. 1990) and methodology of saturation of plant samples (V. P. Moiseev et al. 2009). Sublethal water deficit was determined by the method of T. K. Goryshina et al. 1965 modified by N. I. Bobrovskaya 1971. Observations and analyses were carried out once a month from May to September in the regrowth, budding and flowering phases. The value of the sublethal water deficit was clarified (28.4 %). During the growing season, the varieties did not experience irreversible moisture deficit in the tissues. Chrysanthemum varieties under identical soil-climatic and agrotechnical conditions had the following range of indicators of total water content and water-holding capacity – 70.0‒90.4 % and 19.00‒64.6 %, respectively. It indicates a considerable degree of adaptation. Analysis of variance revealed that varietal differentiation significantly affects the indicators of the water regime; the share of influence varied from 21.17 to 31.72 %. Direct dependence of the indicators of the content of ‘mobile’ moisture on the total water content (y = 0.74x – 21.377) was revealed, as well as the inverse one ‒ the indicators of the content of ‘mobile’ moisture and water-holding capacity (y = 0.74x – 21.377). According to the scale developed by Denisova S. G. and Reut A. A. (2020), four highly drought-tolerant varieties ‘Volny Agideli’, ‘Regina’, ‘Sakmara’, ‘Bardo’ were identified.

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Fertigation Frequency Affects Growth and Water and Nitrogen Use Efficiencies of Swingle Citrumelo Citrus Rootstock Seedlings

HortScience ◽

10.21273/hortsci.45.8.1255 ◽

2010 ◽

Vol 45 (8) ◽

pp. 1255-1259 ◽

Cited By ~ 8

Author(s):

Juan Carlos Melgar ◽

Arnold W. Schumann ◽

James P. Syvertsen

Keyword(s):

Water Use ◽

N Uptake ◽

Dry Weight ◽

Irrigation Frequency ◽

N Uptake Efficiency ◽

Citrus Rootstock ◽

Use Efficiency ◽

Swingle Citrumelo ◽

Fertilizer Solution ◽

Leaf N

We determined if frequency of application of irrigation water plus fertilizer in solution (fertigation) could modify root and shoot growth along with growth per unit nitrogen (N) and water uptake of seedlings of the citrus rootstock Swingle citrumelo growing in a greenhouse. In the first experiment, all plants received the same amount of water with sufficient fertilizer N but in three irrigation frequencies applied in 10 1.5-mL pulses per day, one 15-mL application per day, or 45 mL applied every 3 days. Plants irrigated at the highest frequency grew the least total dry weight and had the highest specific root length. Plants with lowest irrigation frequency grew the most and used the least water so had the highest water use efficiency. There were no irrigation frequency effects on relative growth allocation between shoot and roots, net gas exchange of leaves, or on leaf N. A second experiment used identical biweekly irrigation volumes and fertilizer rates, but water and fertilizer were applied using four frequency combinations: 1) daily fertigation; 2) daily irrigation with fertilizer solution applied every 15 days; 3) fertigation every 3 days; or 4) irrigation every 3 days and fertilizer solution applied every 14 days. Total plant growth was unaffected by treatments, but the highest frequency using the lowest fertilizer concentration grew the greatest root dry weight in the uppermost soil depths. Roots grew less and leaf N was highest when N was applied every 15 days, implying that root N uptake efficiency was increased when fertigated with the highest fertilizer concentration. All plants had similar water use efficiencies. A third experiment was conducted with irrigation every 3 days and with four different N application frequencies: every 3, 6, 12, or 24 days using four fertilizer concentrations but resulting in similar total N amounts every 24 days. There were no differences in growth, gas exchange, or water use efficiency. Given the fact that all treatments received adequate and equal amounts of water and fertilizer, fertigation frequency had only small effects on plant growth, although very high frequency fertigation decreased N uptake efficiency.

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