Physiological Effects of Incomplete Root-zone Wetting on Plant Growth and Their Implications for Irrigation Management

Real-time monitoring of substrate parameters in the root-zone through dielectric sensors is considered a promising and feasible approach for precision irrigation and fertilization management of greenhouse soilless vegetable crops. This research investigates the effects of timer-based (TIMER) compared with dielectric sensor-based irrigation management with different irrigation set-points [SENSOR_0.35, SENSOR_0.30 and SENSOR_0.25, corresponding to substrate volumetric water contents (VWC) of 0.35, 0.30 and 0.25 m3 m−3, respectively] on water use, crop performance, plant growth and physiology, product quality and post-harvest parameters of soilless green bean (Phaseolus vulgaris L., cv Maestrale). In SENSOR treatments, an automatic system managed irrigation in order to maintain substrate moisture constantly close to the specific irrigation set-point. The highest water amount was used in TIMER treatment, with a water saving of roughly 36%, 41% and 47% in SENSOR_0.35, SENSOR_0.30 and SENSOR_0.25, respectively. In TIMER, the leaching rate was ≈31% of the total water consumption, while little leaching (<10%) was observed in SENSOR treatments. TIMER and SENSOR_0.35 resulted in similar plant growth and yield, while irrigation set-points corresponding to lower VWC values (SENSOR_0.30 and SENSOR_0.25) resulted in inadequate water availability conditions and impaired the crop performance. The study confirms that rational sensor-based irrigation allows to save water without compromising anyhow the product quality. In SENSOR irrigation management, in fact, especially in the case of optimal water availability conditions, it was possible to obtain high quality pods, with fully satisfactory characteristics during storage at 7 °C for 15 days.

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Managing Landscape Irrigation to Avoid Soil and Nutrient Losses

EDIS ◽

10.32473/edis-ss586-2013 ◽

2013 ◽

Vol 2013 (11) ◽

Author(s):

George Hochmuth ◽

Laurie Trenholm ◽

Don Rainey ◽

Esen Momol ◽

Claire Lewis ◽

...

Keyword(s):

Natural Environment ◽

Management Practices ◽

Root Zone ◽

Irrigation Management ◽

Critical Factor ◽

Nutrient Losses ◽

County Agents ◽

The Right ◽

Soil And Water

Proper irrigation management is critical to conserve and protect water resources and to properly manage nutrients in the home landscape. How lawns and landscapes are irrigated directly impacts the natural environment, so landscape maintenance professionals and homeowners must adopt environmentally-friendly approaches to irrigation management. After selecting the right plant for the right place, water is the next critical factor to establish and maintain a healthy lawn and landscape. Fertilization is another important component of lawn and landscape maintenance, and irrigation must be applied correctly, especially following fertilization, to minimize potential nutrient losses. This publication supplements other UF/IFAS Extension publications that also include information on the role of soil and the root zone in irrigation management. This publication is designed to help UF/IFAS Extension county agents prepare materials to directly address nutrient losses from lawns and landscapes caused by inadequate irrigation management practices. This 6-page fact sheet was written by George Hochmuth, Laurie Trenholm, Don Rainey, Esen Momol, Claire Lewis, and Brian Niemann, and published by the UF Department of Soil and Water Science, October 2013. http://edis.ifas.ufl.edu/ss586

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Plastic Mulch Color Effects on Light Micro-environment and Watermelon Plant Growth

HortScience ◽

10.21273/hortsci.33.3.474d ◽

1998 ◽

Vol 33 (3) ◽

pp. 474d-474

Author(s):

N.K. Damayanthi Ranwala ◽

Dennis R. Decoteau

Keyword(s):

Plant Growth ◽

Light Transmission ◽

Root Zone ◽

Dry Mass ◽

Plant Responses ◽

Plastic Mulch ◽

Plant Parts ◽

Reflected Light ◽

Total Light ◽

Dry Mass Partitioning

This study was conducted to evaluate the spectral properties of various colored plastic color mulches and to determine the effects of upwardly reflected light from the mulch surfaces on watermelon plant growth when differences in root zone temperatures are minimized. Two-week-old watermelon plants were grown with black mulch, red-painted mulch, SRM-Red mulch (Sonoco, Inc., Harstville, S.C.), and white mulch. Total light reflection (58 μmol·m–2·s–1 in 400–700 nm) and red: far-red (R:FR = 0.44) of reflected light were lower in black mulch and highest in white mulch (634 and 0.92, respectively). Both black mulch and white mulch had same blue:red (B:R = 0.6) while white mulch had higher B:FR (0.58) in reflected light compared to black mulch (0.26). Reflective properties of red mulches were somewhat similar, and R:FR, B:R, and B:FR were 0.8, 0.2, and 0.18, respectively. However, SRM-Red mulch had highest total light (355 μmol·m–2·s–1 in 400–700 nm) transmission through the mulch, and R:FR, B:R, and B:FR were 0.84, 0.28, and 0.23, respectively. Light transmission through the other mulches was nonsignificant. Watermelon plants grown with black mulch and red mulches had higher internode lengths compared to white mulch after 20 days. Further, plants grown under black had significant higher petiole elongation accompanied with higher dry mass partitioning to petioles, and lower partitioning to roots, stems, and leaves. There was no effects of surface mulch color on total plant dry mass or photosynthesis although plants with black had higher transpiration rate. This suggests the differential regulation of dry mass partitioning among plant parts due to mulch color. The similar plant responses with black mulch and white mulch to plants treated with FR or R light at the end of photoperiod implies the involvement of phytochrome regulation of growth due to mulch surface color.

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The effect of seaweed extract on tomato plant growth, productivity and soil

Journal of Applied Phycology ◽

10.1007/s10811-021-02387-2 ◽

2021 ◽

Author(s):

Hashmath Inayath Hussain ◽

Naga Kasinadhuni ◽

Tony Arioli

Keyword(s):

Plant Growth ◽

Tomato Plant ◽

Root Zone ◽

Soil Health ◽

Dry Weight ◽

Bacterial Count ◽

Community Diversity ◽

Seaweed Extract ◽

Total Bacterial Count ◽

Soil Biology

AbstractThis study investigated the effects of seaweed extract (SWE) made from the brown algae Durvillaea potatorum and Ascophyllum nodosum on plants and soil. The application of SWE to soil growing tomato plants showed dual effects. SWE comprehensively improved tomato plant growth (flower clusters, flower number, fruit number, root length, root and shoot dry weight, SPAD) and increased plant productivity (yield and quality). Similarly, SWE application effected soil biology at the soil root zone by increasing total bacterial count and available soil nitrogen and impacting bacterial community diversity with an increase in certain bacterial families linked to soil health. A broader understanding of the effects of SWE on the plant-soil ecosystem may offer breakthrough approaches for sustainable food production.

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Soil moisture assessment based on Sentinel 1/2 and in-situ data: The vineyard case study

10.5194/egusphere-egu21-16507 ◽

2021 ◽

Author(s):

Maria Paula Mendes ◽

Ana Paula Falcão ◽

Magda Matias ◽

Rui Gomes

Keyword(s):

Soil Moisture ◽

Climate Models ◽

Root Zone ◽

Irrigation Management ◽

Management Strategies ◽

Winter Period ◽

Classification Algorithms ◽

Precipitation Regime ◽

Terrain Attributes ◽

Sentinel 2

Vineyards are crops whose production has a major economic impact in the Portuguese economy (~750 million euros) being exported worldwide. As the climate models project a larger variability in precipitation regime, the water requirements of vineyards can change and drip irrigation can be responsible for salt accumulation in the root zone, especially when late autumn and winter precipitation is not enough to leach salts from the soil upper horizons, turning the soil unsuitable for grape production.The aim of this work is to present a methodology to map surface soil moisture content (SMC) in a vineyard, (40 hectares) based on the application of two classification algorithms to satellite imagery (Sentinel 1 and Sentinel 2). Two vineyard plots were considered and three field campaigns (December 2017, January 2018 and May 2018) were conducted to measure soil moisture contents (SMC). A geostatistical method was used to estimate the SM class probabilities according to a threshold value, enlarging the training set (i.e., SMC data of the two plots) for the classification algorithms. Sentinel-1 and Sentinel-2 images and terrain attributes fed the classification algorithms. Both methods, Random Forest and Logistic Regression, classified the highest SMC areas, with probabilities above 14%, located close to a stream at the lower altitudes.RF performed very well in classifying the topsoil zones with lower SMC during the autumn-winter period (F-measure=0.82).This delineation allows the prevention of the occurrence of areas affected by salinization, indicating which areas will need irrigation management strategies to control the salinity, especially under climate change, and the expected increase in droughts.

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Physiological effects of the brown seaweedAscophyllum nodosum)and humic substances on plant growth, enzyme activities of certain pepper plants grown under salt stress

Acta Biologica Hungarica ◽

10.1556/018.68.2018.3.8 ◽

2018 ◽

Vol 69 (3) ◽

pp. 325-335 ◽

Cited By ~ 1

Author(s):

Mahmut Yildiztekin ◽

Atilla Levent Tuna ◽

Cengiz Kaya

Keyword(s):

Salt Stress ◽

Plant Growth ◽

Humic Substances ◽

Enzyme Activities ◽

Physiological Effects ◽

Pepper Plants

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Culture of Hydrilla (Hydrilla verticillata) in Sand Root Media Amended with Three Fertilizers

Weed Science ◽

10.1017/s0043174500026400 ◽

1986 ◽

Vol 34 (1) ◽

pp. 34-39 ◽

Cited By ~ 4

Author(s):

David L. Sutton

Keyword(s):

Plant Growth ◽

Plant Tissue ◽

Root Zone ◽

Hydrilla Verticillata ◽

Dry Weight ◽

Pond Water ◽

Sand Soil ◽

Plant Weight ◽

Root Media ◽

Tuber Production

Hydrilla [Hydrilla verticillata(L.f.) Royle # HYLLI] was grown for 4 to 16 weeks in pans filled with either an organic muck-sand soil, sand, or sand mixed with Osmocote, Esmigran, and dolomite under outdoor conditions in plastic-lined pools with flowing pond water. Dry weight for plants cultured in sand plus the fertilizers was dependent on the concentration of fertilizer and was from 6 to 14 times that of plants cultured in sand alone. Dry weight was also higher for three treatments of sand amended with fertilizer than for plants cultured in the organic muck-sand soil. Water temperature for different growth periods influenced dry weight of hydrilla cultured with all three root media. Tuber production was independent of three levels of fertilizer for 16 weeks of plant growth, but plant weight was dependent on the concentration of nutrients in the root zone. Of nine plant tissue nutrients measured, only phosphorus in both the shoots and roots was dependent on the level of fertilizer in the root zone. This suggests that growth of hydrilla is controlled by nutrients in the root zone. The use of sand amended with various levels of fertilizers may be a way to simulate fertility levels of sediments as a method to study aquatic sites for their potential to support growth of hydrilla.

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Using Soil Solution Monitoring to Determine the Effects of Irrigation Management and Fertigation on Nitrogen Availability in High-density Apple Orchards

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.123.4.706 ◽

1998 ◽

Vol 123 (4) ◽

pp. 706-713 ◽

Cited By ~ 16

Author(s):

D. Neilsen ◽

P. Parchomchuk ◽

G.H. Neilsen ◽

E.J. Hogue

Keyword(s):

Soil Solution ◽

Irrigation Water ◽

Root Zone ◽

Irrigation Management ◽

Sprinkler Irrigation ◽

Loamy Sand ◽

N Availability ◽

Silt Loam ◽

N Concentration ◽

Loam Soil

Direct application of fertilizers in irrigation water (fertigation) is an efficient method of supplying nutrients to fruit trees. Information is needed on the relationship between irrigation and N inputs on N availability in order to target nutrient applications to meet plant demands. Soil solution was collected from permanently installed suction lysimeters and NO3-N concentration was measured over the growing season in three experiments: 1) comparison of sprinkler irrigation + broadcast fertilizer with weekly fertigation + daily drip irrigation; 2) comparison of (NH4)2SO4 or Ca(NO3)2 as N sources under daily fertigation; and 3) comparisons of combinations of irrigation applied at either fixed rates or to meet evaporative demand and fertilizer (Ca(NO3)2) applied daily either at fixed rates or to maintain a given concentration in the fertigation solution in two soil types—loamy sand and silt loam. Trials are located in high density apple plantings of either `Gala' or `Empire' apple (Malus × domestica Borkh.) on M.9 rootstock. Nitrate-N concentration in the soil solution measured at 30 cm deep remained higher, over more of the growing season, for weekly fertigation + daily drip irrigation than for a single broadcast fertilizer application + sprinkler irrigation. With daily Ca(NO3)2 fertigation, soil solution NO3- N concentrations increased and decreased rapidly with the onset and end of fertigation respectively, remained relatively constant during the intervening period and were directly proportional to either the amount of N or the amount of irrigation water added. Daily fertigation with (NH4)2SO4 resulted in less control of NO3-N availability in the root-zone than with Ca(NO3)2, which may be problematic for precise timing of N nutrition. Except for the fixed irrigation rate applied to the loamy sand soil, soil solution NO3-N concentrations at 30 cm beneath the emitter were similar to average concentrations in the fertigating solution, for all methods of irrigation management in both soil types. Elevated NO3-N concentrations in soil solution below the root zone (75 cm deep) were detected in the loamy sand regardless of methods of N application and irrigation although there was some evidence of less leaching to this depth, under scheduled irrigation. In the silt loam soil, considerably lower concentrations of NO3-N were found beneath the root zone than at 30 cm deep for all of irrigation procedures and frequently there was insufficient water moving to 75 cm to provide sample. Tree growth in the loamy sand was less than in the silt loam soil; was limited by low application of irrigation water in 1992 and 1993; was unaffected by NO3-N concentration in the root zone, indicating that N inputs could be minimized by adding N to maintain concentrations of 75 μg·mL-1 or possibly less. Nitrogen inputs may also be reduced if fertilizer N and irrigation water could be retained within the root zone. For coarse-textured soils this will require precise additions of water and possibly soil amendments to improve water holding capacity.

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Mitigation of Nickel Toxicity and Growth Promotion in Sesame through the Application of a Bacterial Endophyte and Zeolite in Nickel Contaminated Soil

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17238859 ◽

2020 ◽

Vol 17 (23) ◽

pp. 8859 ◽

Cited By ~ 1

Author(s):

Muhammad Naveed ◽

Syeda Sosan Bukhari ◽

Adnan Mustafa ◽

Allah Ditta ◽

Saud Alamri ◽

...

Keyword(s):

Plant Growth ◽

Contaminated Soil ◽

Root Zone ◽

Plant Biomass ◽

Growth Promotion ◽

Research Work ◽

Control Treatment ◽

Soil Conditions ◽

Combined Application ◽

Bioavailable Fraction

Nickel (Ni) bioavailable fraction in the soil is of utmost importance because of its involvement in plant growth and environmental feedbacks. High concentrations of Ni in the soil environment, especially in the root zone, may retard plant growth that ultimately results in reduced plant biomass and yield. However, endophytic microorganisms have great potential to reduce the toxicity of Ni, especially when applied together with zeolite. The present research work was conducted to evaluate the potential effects of an endophytic bacterium Caulobacter sp. MN13 in combination with zeolite on the physiology, growth, quality, and yield of sesame plant under normal and Ni stressed soil conditions through possible reduction of Ni uptake. Surface sterilized sesame seeds were sown in pots filled with artificially Ni contaminated soil amended with zeolite. Results revealed that plant agronomic attributes such as shoot root dry weight, total number of pods, and 1000-grains weight were increased by 41, 45, 54, and 65%, respectively, over control treatment, with combined application of bacteria and zeolite in Ni contaminated soil. In comparison to control, the gaseous exchange parameters (CO2 assimilation rate, transpiration rate, stomatal- sub-stomatal conductance, chlorophyll content, and vapor pressure) were significantly enhanced by co-application of bacteria and zeolite ranging from 20 to 49% under Ni stress. Moreover, the combined utilization of bacteria and zeolite considerably improved water relations of sesame plant, in terms of relative water content (RWC) and relative membrane permeability (RMP) along with improvement in biochemical components (protein, ash, crude fiber, fat), and micronutrients in normal as well as in Ni contaminated soil. Moreover, the same treatment modulated the Ni-stress in plants through improvement in antioxidant enzymes (AEs) activities along with improved Ni concentration in the soil and different plant tissues. Correlation and principal component analysis (PCA) further revealed that combined application of metal-tolerant bacterium Caulobacter sp. MN13 and zeolite is the most influential strategy in alleviating Ni-induced stress and subsequent improvement in growth, yield, and physio-biochemical attributes of sesame plant.

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Arbuscular mycorrhizal fungi alleviate abiotic stresses in potato plants caused by low phosphorus and deficit irrigation/partial root-zone drying

The Journal of Agricultural Science ◽

10.1017/s0021859618000023 ◽

2018 ◽

Vol 156 (1) ◽

pp. 46-58 ◽

Cited By ~ 13

Author(s):

Caixia Liu ◽

Sabine Ravnskov ◽

Fulai Liu ◽

Gitte H. Rubæk ◽

Mathias N. Andersen

Keyword(s):

Plant Growth ◽

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Growth Response ◽

Root Zone ◽

Plant Biomass ◽

N Uptake ◽

Arbuscular Mycorrhizal ◽

P Fertilization ◽

Low Phosphorus

AbstractDeficit irrigation (DI) improves water use efficiency (WUE), but the reduced water input often limits plant growth and nutrient uptake. The current study examined whether arbuscular mycorrhizal fungi (AMF) could alleviate abiotic stress caused by low phosphorus (P) fertilization and DI.A greenhouse experiment was conducted with potato grown with (P1) or without (P0) P fertilization, with AMF (M1+:Rhizophagus irregularisor M2+:Glomus proliferum) or AMF-free control (M−) and subjected to full irrigation (FI), DI or partial root-zone drying (PRD).Inoculation of M1+ and M2+ maintained or improved plant growth and P/nitrogen (N) uptake when subjected to DI/PRD and P0. However, the positive responses to AMF varied with P level and irrigation regime. Functional differences were found in ability of AMF species alleviating plant stress. The largest positive plant biomass response to M1+ and M2+ was found under FI, both at P1 and P0 (25% increase), while plant biomass response to M1+ and M2+ under DI/PRD (14% increase) was significantly smaller. The large growth response to AMF inoculation, particularly under FI, may relate to greater photosynthetic capacity and leaf area, probably caused by stimulation of plant P/N uptake and carbon partitioning toward roots and tubers. However, plant growth response to AMF was not related to the percentage of AMF root colonization. Arbuscular mycorrhizal fungi can maintain and improve P/N uptake, WUE and growth of plants both at high/low P levels and under FI/DI. If this is also the case under field conditions, it should be implemented for sustainable potato production.

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