Steel Slag Raises pH of Greenhouse Substrates

Dolomitic lime (DL) is the primary liming agent used for increasing pH in peatmoss-based substrates. Steel slag (SS) is a byproduct of the steel manufacturing industry that has been used to elevate field soil pH. The objective of this research was to determine the pH response of a peatmoss-based greenhouse substrate to varying rates of DL or SS. Two experiments were conducted with an 85 peatmoss : 15 perlite substrate. In the first experiment, the substrate was amended with 0, 2.4, 4.8, or 7.1 kg·m−3 of either DL or SS. Half of the containers remained fallow and the other half were potted with a single sunflower (Helianthus annuus L. ‘Pacino Gold’). In the second experiment, fallow containers were only used with the substrate amended with 0, 2.4, 4.8, 9.5, or 14.2 kg·m−3 DL or SS. Sunflower were measured for relative foliar chlorophyll content, shoot mass, root ratings, and foliar nutrient concentrations. Substrate electrical conductivity (EC) and pH were measured weekly using the pour-through procedure. All sunflower plants grew vigorously, although nonamended controls had less shoot dry weight than those amended with DL or SS. There were minor differences in foliar concentration of N, Ca, Mg, and Mn; however, these differences did not adversely affect plant growth. Summarizing across both experiments, EC was affected by treatment and time, although all substrates had EC readings within the range recommended for floriculture crop production (1.0–4.6 mS⋅cm−1). Substrate pH differed slightly in Expt. 1 between fallow and planted containers. Substrate pH increased exponentially with increasing rates of either DL or SS. Maximum pH in fallow DL and SS amended substrates was 6.57 and 6.93, respectively, in Expt. 1 and 6.85 and 7.67, respectively, in Expt. 2. The SS used in this experiment resulted in a greater pH response than DL with higher application rates. SS is a viable material for raising pH of soilless substrates.

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Adaptation of Lupinus angustifolius L. and L. pilosus Murr. to calcareous soils

Australian Journal of Agricultural Research ◽

10.1071/ar98177 ◽

1999 ◽

Vol 50 (6) ◽

pp. 1027 ◽

Cited By ~ 4

Author(s):

J. D. Brand ◽

C. Tang ◽

A. J. Rathjen

Keyword(s):

Calcareous Soils ◽

South Australia ◽

Clay Content ◽

Dry Weight ◽

Lupinus Angustifolius ◽

Nutrient Concentrations ◽

Carbonate Content ◽

Soil Factors ◽

Shoot Dry Weight ◽

Caco3 Content

Current varieties of narrow-leafed lupin (Lupin angustifolius L.) are poorly adapted to alkaline and calcareous soils found commonly throughout the south-estern Australian cropping zone. Apot experiment compared the growth of Lupinus angustifolius cv. Gungurru with L. pilosus P20954 in a range of soils collected throughout South Australia. The soils displayed a range of texture (clay, 3–82%), pH (1:5 soil:H2O, 7·0–9·6), and calcium carbonate content (CaCO3, 0–47%). Potting mix (pH 5·8) was used as the control. The plants were grown for 7 weeks with weekly measurements of chlorosis score and leaf number. At harvest, dry weights were recorded and the youngest fully expanded leaves were analysed for nutrient concentrations. The line P20954 grew much better in all the soils than Gungurru in terms of plant dry weight relative to the control soil, this being particularly evident in the calcareous soils. Chlorosis score correlated highly with shoot dry weight for Gungurru, but not for P20954. The main soil factor contributing to the chlorosis score of Gungurru was CaCO3 content, whereas none of the soil factors significantly affected P20954, although in Weeks 2 and 3 chlorosis score correlated with CaCO3 content. The dry weight of Gungurru was affected by a combination of factors including clay content, pH, and CaCO3 content, whereas the dry weight of P20954 was affected by most of the soil factors measured. The dry weight of P20954 was positively correlated with aluminium and magnesium concentrations. Concentrations of all nutrients were above critical levels for both genotypes grown in all soils. The results indicate that L. pilosus has the potential to be grown in areas where current varieties of L. angustifolius are poorly adapted.

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Evaluating Calibrachoa (Calibrachoa ×hybrida Cerv.) Genotype Sensitivity to Iron Deficiency at High Substrate pH

HortScience ◽

10.21273/hortsci11038-16 ◽

2016 ◽

Vol 51 (12) ◽

pp. 1452-1457 ◽

Cited By ~ 1

Author(s):

Ryan W. Dickson ◽

Paul R. Fisher ◽

Sonali R. Padhye ◽

William R. Argo

Keyword(s):

Iron Deficiency ◽

Ph Effect ◽

Iron Concentration ◽

Dry Weight ◽

Percent Reduction ◽

Crop Species ◽

High Substrate ◽

Deficiency Symptoms ◽

Shoot Dry Weight ◽

Substrate Ph

Floriculture crop species that are inefficient at iron uptake are susceptible to developing iron deficiency symptoms in container production at high substrate pH. The objective of this study was to compare genotypes of iron-inefficient calibrachoa (Calibrachoa ×hybrid Cerv.) in terms of their susceptibility to showing iron deficiency symptoms when grown at high vs. low substrate pH. In a greenhouse factorial experiment, 24 genotypes of calibrachoa were grown in peat:perlite substrate at low pH (5.4) and high pH (7.1). Shoot dry weight, leaf SPAD chlorophyll index, flower index value, and shoot iron concentration were measured after 13 weeks at each substrate pH level. Of the 24 genotypes, analysis of variance (ANOVA) found that 19 genotypes had lower SPAD and 18 genotypes had reduced shoot dry weight at high substrate pH compared with SPAD and dry weight at low substrate pH. High substrate pH had less effect on flower index and shoot iron concentration than the pH effect on SPAD or shoot dry weight. No visual symptoms of iron deficiency were observed at low substrate pH. Genotypes were separated into three groups using k-means cluster analysis, based on the four measured variables (SPAD, dry weight, flower index, and iron concentration in shoot tissue). These four variables were each expressed as the percent reduction in measured responses at high vs. low substrate pH. Greater percent reduction values indicated increased sensitivity of genotypes to high substrate pH. The three clusters, which about represented high, medium, or low sensitivity to high substrate pH, averaged 59.7%, 42.8%, and 25.2% reduction in SPAD, 47.7%, 51.0%, and 39.5% reduction in shoot dry weight, and 32.2%, 9.2%, and 27.7% reduction in shoot iron, respectively. Flowering was not different between clusters when tested with ANOVA. The least pH-sensitive cluster included all four genotypes in the breeding series ‘Calipetite’. ‘Calipetite’ also had low shoot dry weight at low substrate pH, indicating low overall vigor. There were no differences between clusters in terms of their effect on substrate pH, which is one potential plant iron-efficiency mechanism in response to low iron availability. This experiment demonstrated an experimental and statistical approach for plant breeders to test sensitivity to substrate pH for iron-inefficient floriculture species.

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Potted Gerbera Production in a Subirrigation System Using Low-concentration Nutrient Solutions

HortScience ◽

10.21273/hortsci.39.6.1283 ◽

2004 ◽

Vol 39 (6) ◽

pp. 1283-1286 ◽

Cited By ~ 24

Author(s):

Youbin Zheng ◽

Thomas Graham ◽

Stefan Richard ◽

Mike Dixon

Keyword(s):

Nutrient Solution ◽

Final Stage ◽

Crop Production ◽

Dry Weight ◽

Interveinal Chlorosis ◽

Nutrient Levels ◽

Stage 4 ◽

Total Dry Weight ◽

Substrate Ph ◽

Nutrient Solutions

To determine whether currently used commercial nutrient solution concentrations can be reduced during the final stage (last 4 to 5 weeks) of production of potted gerbera (Gerbera jamesonii `Shogun') under recirculating subirrigation conditions, plants were grown under one of four nutrient levels (10%, 25%, 50%, and 100% of full strength). Nutrient concentration levels did not affect leaf area, flower number and appearance, and plant total dry weight. There were no significant differences in the greenness (as measured by SPAD meter) of leaves from plants that received the 50% and 100% strength nutrient solutions. However, leaves from plants that received the 10% and 25% strength solution showed significantly less greenness than that of the plants that received 50% and 100% strength nutrient solutions. There were interveinal chlorosis symptoms on the younger leaves of some plants in the 10% and 25% strength nutrient treatments. It is suspected that this interveinal chlorosis was due to iron (Fe) deficiency caused by the increased substrate pH. It is concluded that the nutrient solution concentrations typically used for potted gerbera production in commercial greenhouses at the final stage (4 to 5 weeks) under recirculating subirrigation conditions, can be safely reduced by at least 50% without adversely affecting crop production. Nutrient salts accumulated in the top section of the growth substrate under all treatments levels; however, no phytotoxic effects were observed. No differences in water use (141 mL per plant per day) were observed amid the various nutrient levels. Fertilizer inputs were reduced in the 50%, 25%, and 10% treatments by 54%, 75%, and 90% respectively, relative to the 100% treatment. After 4 weeks under recirculating conditions, the qualities of the nutrient solutions were still within acceptable limits.

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Co-composted Biochar Enhances Growth, Physiological, and Phytostabilization Efficiency of Brassica napus and Reduces Associated Health Risks Under Chromium Stress

Frontiers in Plant Science ◽

10.3389/fpls.2021.775785 ◽

2021 ◽

Vol 12 ◽

Author(s):

Muhammad Naveed ◽

Bisma Tanvir ◽

Wang Xiukang ◽

Martin Brtnicky ◽

Allah Ditta ◽

...

Keyword(s):

Antioxidant Enzyme ◽

Health Risks ◽

Contaminated Soil ◽

Enzyme Activities ◽

Crop Production ◽

Industrial Effluents ◽

Dry Weight ◽

Antioxidant Enzyme Activities ◽

Maximum Increase ◽

Shoot Dry Weight

Among heavy metals, chromium (Cr) contamination is increasing gradually due to the use of untreated industrial effluents for irrigation purposes, thereby posing a severe threat to crop production. This study aimed to evaluate the potential of compost, biochar (BC), and co-composted BC on the growth, physiological, biochemical attributes, and health risks associated with the consumption of Brassica grown on Cr-contaminated soil. Results revealed that Cr stress (Cr-25) significantly reduced the growth and physiological attributes and increased antioxidant enzyme activities in Brassica, but the applied amendments considerably retrieved the negative effects of Cr toxicity through improving the growth and physiology of plants. The maximum increase in plant height (75.3%), root length (151.0%), shoot dry weight (139.4%), root dry weight (158.5%), and photosynthetic rate (151.0%) was noted with the application of co-composted BC under Cr stress (Cr-25) in comparison to the control. The application of co-composted BC significantly reduced antioxidant enzyme activities, such as APX (42.5%), GP (45.1%), CAT (45.4%), GST (47.8%), GR (47.1%), and RG (48.2%), as compared to the control under Cr stress. The same treatment reduced the accumulation of Cr in grain, shoot, and roots of Brassica by 4.12, 2.27, and 2.17 times and enhanced the accumulation in soil by 1.52 times as compared to the control. Moreover, the application of co-composted BC significantly enhanced phytostabilization efficiency and reduced associated health risks with the consumption of Brassica. It is concluded that the application of co-composted BC in Cr-contaminated soil can significantly enhance the growth, physiological, and biochemical attributes of Brassica by reducing its uptake in plants and enhanced phytostabilization efficiency. The tested product may also help in restoring the soils contaminated with Cr.

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Effects of Potassium Availability on Growth and Development of Barley Cultivars

Agronomy ◽

10.3390/agronomy11112269 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2269

Author(s):

Widad Al Azzawi ◽

Muhammad Bilal Gill ◽

Foad Fatehi ◽

Meixue Zhou ◽

Tina Acuña ◽

...

Keyword(s):

Crop Production ◽

Dry Weight ◽

Major Effect ◽

Grain Weight ◽

Grain Number ◽

Barley Cultivars ◽

Shoot Dry Weight ◽

Spike Number ◽

Potassium Supply ◽

The Impact

Potassium deficiency is one of the major issues affecting crop production around the globe. Giving the high cost of potassium fertilizers and environmental concerns related to inappropriate fertilization practices, developing more potassium use efficient (KUE) varieties is critical for sustainable food production in agricultural systems. In this study, we analysed the impact of potassium availability on agronomical attributes of thirty barley genotypes grown at four different levels of potassium (0.002 mM, 0.02 mM, 2 mM, 20 mM) under glasshouse conditions. The results showed that the availability of potassium in the soil had a major effect on yield components i.e., spike number, grain number and grain weight. Furthermore, grain weight showed a strong correlation with grain number and spike number at all levels of potassium supply. Although an increase in potassium supply led to an increase in plant height in all genotypes, the correlation with grain weight was very weak at all levels. Potassium supplementation caused an increase in shoot dry weight, which also showed a weak correlation with grain weight at the 0.002 mM potassium supply level. The genotypes Gebeina, Skiff, YF374, Flagship and YF374 were highly efficient in performing at suboptimal K supply levels and, thus, can be recommended to be grown in K-impoverished soils. We also suggest that grain and spike numbers could be used as proxies for KUE studies, to construct DH lines and identify QTL to improve low potassium tolerance and KUE in barley.

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Comparison of Growth and Alkalinity-induced Responses in Two Cultivars of Hibiscus (Hibiscus rosa-sinensis L.)

HortScience ◽

10.21273/hortsci.41.7.1704 ◽

2006 ◽

Vol 41 (7) ◽

pp. 1704-1708 ◽

Cited By ~ 4

Author(s):

Luis Alonso Valdez-Aguilar ◽

David William Reed

Keyword(s):

Root Zone ◽

Reductase Activity ◽

Dry Weight ◽

Hydroponic Culture ◽

Root Mass ◽

Shoot Dry Weight ◽

Hibiscus Rosa Sinensis ◽

Growing Medium ◽

Ph Increase ◽

Shoot Mass

Response to alkalinity was evaluated in two hibiscus cultivars, Bimini Breeze and Carolina Breeze, grown in a soilless growing medium and in hydroponic culture. For soilless growing medium, plants were potted in a sphagnum peat–perlite-based substrate and irrigated with solutions containing 0 to 10 mm NaHCO3 for 12 weeks. In hydroponic culture, bare-rooted plants were transferred to a 9-L tray containing a Hoagland's nutrient solution prepared with NaHCO3 at the concentrations previously indicated. In soilless growing medium, shoot dry weight was minimally affected by NaHCO3 concentration for `Bimini Breeze', but `Carolina Breeze' exhibited a significant decrease in shoot mass with increasing NaHCO3 concentration. In hydroponic culture, increasing concentration of NaHCO3 induced a decrease in shoot and root mass in both cultivars, but root mass decrease was more pronounced in `Bimini Breeze'. In soilless growing medium, increasing the concentration of NaHCO3 caused an increase in growing medium pH. The pH increase was less pronounced for `Bimini Breeze' than for `Carolina Breeze', indicating a higher capacity for root zone acidification by `Bimini Breeze'. Newly developed leaves of both cultivars showed increasing chlorosis with increasing NaHCO3 concentration. However, `Bimini Breeze' was more tolerant because, according to regression models, 5.7 mm NaHCO3 would be required to reduce chlorophyll levels by 10%, compared with 2.2 mm for `Carolina Breeze', when grown in soilless medium. Fe reductase activity decreased when `Carolina Breeze' plants were grown in 5 mm NaHCO3. However, in `Bimini Breeze', Fe reductase activity was enhanced. These observations indicate that the increased tolerance of `Bimini Breeze' to increasing alkalinity is the result of enhanced Fe reductase activity and increased acidification of the root zone.

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Fertilizer, Irrigation, and Natural Ericaceous Root and Soil Inoculum (NERS): Effects on Container-grown Ericaceous Nursery Crop Biomass, Tissue Nutrient Concentration, and Leachate Nutrient Quality

HortScience ◽

10.21273/hortsci.46.5.799 ◽

2011 ◽

Vol 46 (5) ◽

pp. 799-807 ◽

Cited By ~ 2

Author(s):

Gladis M. Zinati ◽

John Dighton ◽

Arend-Jan Both

Keyword(s):

Nutrient Concentration ◽

Irrigation System ◽

Block Design ◽

Dry Weight ◽

Fertilizer Application ◽

Nutrient Concentrations ◽

Fertilizer Rate ◽

Nutrient Runoff ◽

Shoot Dry Weight ◽

Substrate Medium

We tested the effects of using an inoculum containing natural ericoid roots and soil (NERS) with two fertilizer and irrigation rates on plant growth, shoot (stems and leaves) nutrient concentration, leachate quality, and mycorrhizal colonization of container-grown Coast Leucothoe [Leucothoe axillaris (Lam.) D. Don] and Japanese Pieris [Pieris japonica (Thunb.) D. Don ex G. Don]. Uniform rooted liners were grown in 10.8-L containers in a pine bark, peatmoss, and sand (8:1:1 by volume) substrate medium in a randomized complete block design with four replications. A controlled-release fertilizer, Polyon® Plus 14-16-8 (14N–7P–6.6K), was incorporated in the substrate medium at the 100% manufacturer's recommended fertilizer rate [representing high fertilizer rate (HF)] (56 g per container) to supply 7.84 g nitrogen (N) and at 50% the manufacturer's recommended rate [representing low fertilizer rate (LF)]. Plants were irrigated using a cyclic drip irrigation system at high (HI) and low (LI) irrigation rates calibrated to supply 25.2 L of water and 16.8 L per week, respectively. On average, NERS inoculation increased shoot growth of Leucothoe and Pieris by 56% and 60%, respectively. Shoots of Leucothoe inoculated with NERS had higher N, phosphorus (P), magnesium (Mg), and manganese (Mn) concentrations than non-inoculated plants. At LF, nitrous-N (NOx-N) and orthophosphorus (PO4-P) concentrations in the leachate were reduced by 53% from Leucothoe and 62% from Pieris compared with HF-treated plants. A reduction of 37% and 36% in PO4-P concentration in leachates from Leucothoe and Pieris, respectively, were achieved at the reduced irrigation (LI) rate. The NERS inoculation reduced PO4-P concentrations in leachate from Leucothoe by 26% and NOx-N concentration by 33% in leachates from Pieris compared with non-inoculated plants. Compared with plants grown in the HI–HF treatment, the combination of LI–LF treatment reduced NOx-N concentrations in leachates from Leucothoe by 60% (P = 0.016) and reduced PO4-P leachate concentrations from Pieris by 72% (P = 0.0096). Decreasing the fertilizer rate to 50% of the recommended rate and the irrigation rate to 67% of the recommended rate in conjunction with the incorporation of NERS reduced leachate nutrient concentrations of two main water pollutants (NOx-N and PO4-P). Adopting the practice of adding NERS containing fungi and bacteria can be an effective system to increase shoot dry weight, allow reduction in fertilizer application, conserve water for irrigation, and minimize subsequent nutrient runoff in nursery operations.

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Crabapple and Lilac Growth and Root-zone Temperatures in Northern Nursery Production Systems

HortScience ◽

10.21273/hortsci.45.1.30 ◽

2010 ◽

Vol 45 (1) ◽

pp. 30-35 ◽

Cited By ~ 3

Author(s):

Catherine A. Neal

Keyword(s):

Production Systems ◽

Root Zone ◽

Dry Weight ◽

Plastic Container ◽

Shoot Dry Weight ◽

Common Lilac ◽

Ground System ◽

Nursery Production ◽

Landscape Establishment ◽

Shoot Mass

Crabapple (Malus ‘Donald Wyman’) and common lilac (Syringa vulgaris ‘Monge’) were grown from liners to marketable size in five production systems: field-grown, plastic container, pot-in-pot (PiP), bag-in-pot (BiP), and above-ground system (AGS). The objectives were to compare growth in modified container systems, which could potentially eliminate overwintering requirements in northern production nurseries and to compare the effects on tree root growth during landscape establishment. There were no significant differences in crabapple root or shoot mass after two seasons except PiP dry root weights exceeded field-grown trees. For lilacs, there were significant differences in growth and shoot dry weight with field-grown and PiP plants being largest. PiP root-zone temperatures (RZTs) were similar to field-grown RZTs. Container, BiP, and AGS systems all exceeded lethal high and low RZT thresholds, resulting in root damage. Five trees from each treatment were transplanted into a low-maintenance landscape and dug up 3 years later. There were no significant differences in top growth, but the effects of the production systems were evident in the root architecture. BiP and field-grown trees had fewest root defects and the greatest number of roots extending into the landscape soil.

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In Vitro Screening of Soybean Genotypes under Salinity Stress

International Journal of Applied Sciences and Biotechnology ◽

10.3126/ijasbt.v4i2.15100 ◽

2016 ◽

Vol 4 (2) ◽

pp. 207-212

Author(s):

M.K. Hasan ◽

K.M. Nasiruddin ◽

M. Al-Amin ◽

A.K.M.S. Hossain

Keyword(s):

Crop Production ◽

Arid Regions ◽

Principal Component ◽

Dry Weight ◽

Limiting Factors ◽

Percent Reduction ◽

Shoot Dry Weight ◽

Soybean Genotypes ◽

Total Dry Weight

Salinity is one of the most limiting factors for successful crop production in in arid and semi-arid regions of the world. Thirty eight soybean genotypes were screened at 8mMNaCl under in vitro condition. Salinity reduced Shoot dry weight, Root dry weight and Plant height. Salt susceptibility index was fully and positive correlated with percent reduction of total dry weight. Principal component analysis showed that the first two components were extracted that comprises of about 98.6% of the total variation in the genotypes. Based on the K-means clustering, 8, 6, 12 and 12 genotypes were categorized under cluster II, IV, III and I and considered as tolerant, moderately tolerant, moderately susceptible and susceptible which represents the 21, 16, 31.5 and 31.5%, respectively. Genotypes Shohag, AGS 313, PK 416, AGS 66, MACS 57, AGS 195, GC 308, AGS 129 were found relatively tolerant to salinity.Int J Appl Sci Biotechnol, Vol 4(2): 207-212

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Heritability in the early nodulation of F3 and F4 soybean lines

Canadian Journal of Plant Science ◽

10.4141/p96-098 ◽

1997 ◽

Vol 77 (2) ◽

pp. 201-205 ◽

Cited By ~ 8

Author(s):

D. L. Pazdernik ◽

P. H. Graham ◽

J. H. Orf

Keyword(s):

Glycine Max ◽

Growth Stage ◽

Dry Weight ◽

Plant Performance ◽

Nodule Development ◽

Plant Introductions ◽

Shoot Dry Weight ◽

Glycine Max L ◽

Shoot Mass ◽

Two Populations

We have previously identified differences among soybean [Glycine max (L.) Merr.] lines in early nodulation and N2 fixation, and related early nodule development and overall plant performance under N-limited field conditions. The objectives of the present study were: 1) to estimate heritabilities for nodule fresh weight (NFW), shoot dry weight (SDW), and root dry weight (RDW) determined 17 d after inoculation (DAI); 2) to examine genetic variation for total nodule soluble protein (TSOLP) at 17 DAI, and SDW and shoot N derived from fixation (SNdfa) at the R5 growth stage; and 3) to assess relationships between early nodulation and subsequent R5 shoot mass and SNdfa. The two populations used were derived from the Minnesota-adapted cultivars Kasota and Parker, and two plant introductions PI 437966 and PI 384469B. Genetic variances within populations were significant for most traits measured at 17 DAI, and at the R5 growth stage. Heritability estimates ranged from 0.79–0.82 for NFW, 0.51–0.56 for SDW, and 0.38–0.40 for RDW, with SDW also correlated with seed size at 17 DAI (r = 0.88**). Additional correlation analyses showed SNdfa correlated with NFW (r = 0.33**) and TSOLP (r = 0.46**). The results of this study suggest that gains from selection are possible for NFW and SDW at early stages of plant development. Key words: Glycine max (L.) Merr., nodulation, nitrogen fixation, heritabilitynot available

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