Nitrogen Management of Drip-iIrrigated Peppers

Inadequate N can reduce growth and yield, but excess N can be uneconomical and environmentally harmful. Our objective was to investigate the potential for using fertigation and on-farm plant-nutrient monitoring to improve the efficiency of N fertilizer use by bell peppers (Capsicum annuum L.). Two N fertilizer treatments were compared: 1) all N applied preplant and 2) one-third of the N applied preplant and the remainder injected into the drip-irrigation lines throughout the growing season. Total application rates were N at 118 kg·ha–1 for both treatments. Data were collected for total yield, marketable yield, and fruit size. Leaf and petiole samples were collected every 2 weeks and were used to monitor plant N status throughout the growing season. A Horiba/Cardy nitrate meter was used to measure nitrate concentrations in freshly-pressed petiole sap. A SPAD chlorophyll meter was used to measure leaf chlorophyll content and give an indirect measure of leaf N concentrations. Subsamples of leaves and petioles also were saved for conventional laboratory analyses. Whole (aboveground) plant samples were collected every 2 weeks, analyzed, and used to calculate differences in N accumulation. Suction cup samplers were installed at the 24-in soil depth and water samples collected every 1 to 2 weeks for nitrate analysis. Except for early in the growing season, petiole sap nitrate and leaf chlorophyll were higher in the fertigation treatment. Plant dry matter and total N accumulation also were much larger, but fertigation did not increase yield. Nitrate leaching was greater early in the season with 100% preplant N, but later in the season it was greater with fertigation. Data suggested that adequate plant N, reduced nitrate leaching, and equivalent yields are possible with fertigation at reduced N-rates compared to 100% preplant fertilizer applications.

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Bio-fortified Compost as A Substitute for Chemical N Fertilizer for Growth, N Accumulation, and Yield of Sweet Corn

Akta Agrosia ◽

10.31186/aa.22.2.84-94 ◽

2020 ◽

Vol 22 (2) ◽

pp. 84-94

Author(s):

Marwanto Marwanto ◽

Shinta Puspita Wati ◽

Atra Romeida ◽

Merakati Handajaningsih ◽

Teguh Adiprasetyo ◽

...

Keyword(s):

Crop Yield ◽

Sweet Corn ◽

Block Design ◽

Chemical Fertilizer ◽

N Fertilizer ◽

Growth And Yield ◽

Partial Substitution ◽

Inorganic N ◽

N Accumulation ◽

Total N

ABSTRACTFinding the appropriate method of fertilizer application to simultaneously enhance farm productivity and ensure ecosystem sustainability has been receiving a lot of attention. A field experiment was carried in the Research Plot Agriculture Faculty Bengkulu University Campus Indonesia in 2017. The purpose of this study was (1) to assess the significant effects of inorganic N fertilizer (IF) substitution with bio-fortified compost (BC) under equal N conditions on growth, N accumulation, and yield of sweet corn, and (2) to determine the appropriate level to which inorganic N fertilizer could be reduced and equivalently replaced by bio-fortified compost to promote sweet corn growth and yield. The treatments consisted of six different proportions of inorganic N fertilizer (IF) substitution with bio-fortified compost (BC). Each treatment was designed on the basis of equal amount of total N input from a combination of both fertilizers (138 kg N ha-1). They were arranged in a randomized block design with 3 replications. They included (1) 100% IF plus 0% BC, (2) 75% IF plus 25% BC, (3) 50% IF plus 50% BC, (4) 25% IF plus 75%, (5) 0% IF plus 100% BC, and (6) no IF and no BC. The results showed that the increasing proportion of IF replaced by BC resulted in an increase for all variables (except for plant height) but they decreased when 100% IF substitution with 100% BC was applied. Among the partial substitution treatments, 50% IF plus 50% BC consistently produced the best growth, N accumulation, and yield increase. Treatments of 50% IF plus 50% BC and 25% IF plus 75% BC produced the highest green cob weight with husk per plot (10.74 – 10.84 kg plot-1), which was 16% to 19% higher than treatment of 100% IF plus % BC. The three partial substitution treatments produced crop yield components as good as treatment of 100% IF plus 0% BC. Treatment of 0% IF plus 100% BC reduced plant growth, N accumulation, and crop yield and its components. The appropriate level to which IF could be reduced and equivalently replaced by BC was at the range of 25% to 75%. Hence, a suitable replacement of inorganic N fertilizer with bio-fortified compost is considered a reasoned way to simultaneously increase crop yield and reduce environmental degradation.Keywords: organic fertilizer, chemical fertilizer, bio-fortification, chemical fertilizer substitution, bio-fortified compost

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Poultry manure effects on soil nitrogen processes and nitrogen accumulation in red raspberry

Canadian Journal of Plant Science ◽

10.4141/p99-136 ◽

2000 ◽

Vol 80 (4) ◽

pp. 849-860 ◽

Cited By ~ 13

Author(s):

D. M. Dean ◽

B. J. Zebarth ◽

C. G. Kowalenko ◽

J. W. Paul ◽

K. Chipperfield

Keyword(s):

Dry Matter ◽

Poultry Manure ◽

Growing Season ◽

Rubus Idaeus ◽

Inorganic N ◽

N Accumulation ◽

Total N ◽

Soil Inorganic N ◽

History Of ◽

N Management

This study examined the effects of solid poultry layer manure addition on soil N processes and on dry matter and N accumulation in red raspberry (Rubus idaeus L.). In trials conducted in two years, approximately 50% of the 400 kg total N ha−1 applied as manure was recovered as soil inorganic N 1 mo after manure application when manure was incorporated within 4 h of application. Three trials were conducted in two commercial raspberry fields: one with no history of manure use and one other with a history of heavy annual applications of poultry manure. Treatments included 55 kg N ha−1 as NH4NO3, 100 or 200 kg total N ha−1 as manure, and a control that received no manure or fertilizer N. Soil inorganic N to 60 cm depth was measured throughout the growing season. Berry yield was estimated, and dry matter and N accumulation was determined in floricanes at first berry ripening and in primocanes at the end of the growing season. Few significant effects of N fertilization were measured for any crop yield, growth or N accumulation parameter. This was attributed to the large (>150 kg N ha−1) supply of N to the crop in the unamended soil, primarily from soil N mineralization. Dry matter accumulation in the fruiting clusters was strongly correlated to estimated berry yield, and may provide a simple means for assessing relative yield within experiments. Soil nitrate measured in August after berry harvest may serve as a "report card" to assess N management in the current growing season, to refine fertilizer N management for subsequent growing seasons, and as an index of the risk of nitrate leaching over the following fall and winter in south coastal British Columbia. Key words: Nitrogen mineralization, nitrate leaching, manure N availability, Rubus idaeus

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Differences in growth and yield responses to Aphis gossypii Glover between different okra varieties

Plant Protection Science ◽

10.17221/2250-pps ◽

2008 ◽

Vol 43 (No. 3) ◽

pp. 109-117 ◽

Cited By ~ 7

Author(s):

H.K. Shannag ◽

J.M. Al-Qudah ◽

I.M. Makhadmeh ◽

N.M. Freihat

Keyword(s):

Leaf Area ◽

Aphis Gossypii ◽

Total Yield ◽

Dry Weight ◽

Growing Season ◽

Growth And Yield ◽

Experimental Plant ◽

Local Reduction ◽

Yield Responses ◽

Aphid Populations

The reactions of five commercial varieties of okra, <i>Abelmoschus esculentus</i>, to <i>A. gossypii</i> were evaluated under semiarid field conditions. Each experimental plant of varieties Clemson spineless, Clemson spineless 80, Lee, Perkins dwarf, and Local was infested 60 days after emergence by three late-nymphal instars of the aphid. The results showed that aphid populations increased constantly on the varieties, except for days 42 and 49 after infestation, attaining a peak at about the end of the growing season. Differences in aphid densities were recorded between varieties. The aphids were most numerous on var. Local, while lowest in number on var. Lee. Infestation by aphids on okra varieties reduced yield by 57% on var. Perkins dwarf, 56% on var. Lee, 24% on var. Clemson spineless, 21% on var. Clemson spineless 80, and 5% on var. Local. Reduction in the number of pods produced per plant followed the same pattern as observed for total yield. Aphids had not altered significantly the vegetative plant growth at day 37 following infestation. At day 66, a substantial decrease in shoot fresh and dry weights and also leaf area was evident on var. Perkins dwarf while on var. Clemson spineless only the leaf area was significantly reduced. Moreover, aphid-free controls varied widely in their growth and productivity at the end of growing season. Varieties Clemson spineless and Clemson spineless 80 produced the highest total yield and pod numbers, var. Local the lowest. The varieties Perkins dwarf and Clemson spineless produced significantly higher shoot fresh and dry weight, as well as leaf area, than vars. Lee and Local.

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EFFECTS OF NITROGEN RATES ON SUMMER SQUASH GROWTH AND YIELD

HortScience ◽

10.21273/hortsci.41.3.506c ◽

2006 ◽

Vol 41 (3) ◽

pp. 506C-506

Author(s):

Camille E. Esmel ◽

Bielinski M. Santos ◽

James P. Gilreath

Keyword(s):

Growth And Yield ◽

Organic N ◽

Yield Response ◽

Vegetable Production ◽

Florida Current ◽

Marketable Yield ◽

N Accumulation ◽

Plant Vigor ◽

Summer Squash ◽

Petiole Sap

Nitrogen (N) is the most growth-limiting for vegetable production in sandy soils. In Florida, current recommendations for preplanting N applications (100 lb/acre of N) in `Crookneck' summer squash (Cucurbita pepo) differ from those used by the growers (>200 lb/acre). Therefore, two field studies were conducted in Ruskin and Balm, Fla., to examine the effect of 50, 100, 150, 200, 250, and 300 lb/acre of N on summer squash growth and yield. Variables collected during this study were plant vigor (0–10 scale, where 0 = dead plant) at 3 and 7 weeks after planting (WAP), petiole sap nitrate-nitrogen (NO3-N) at 4 and 8 WAS, and marketable yield starting on 4 WAS (13 and 10 harvests in Ruskin and Balm, respectively). In Ruskin, plant vigor increased linearly with N rates, whereas there was no significant N effect in Balm. No differences in petiole sap NO3-N were observed in either location. In Ruskin, there was a rapid marketable yield increase (§25%) between 50 and 100 lb/acre of N, followed by no change afterwards. In contrast, there was no yield response in Balm. In the latter location, no crop had been established in the previous 3 years, enabling the soil to maximize its organic N accumulation (>40 lb/acre organic-N), whereas in Ruskin the experimental location had been continuously planted during the last three seasons (§25 lb/acre organic-N). The data demonstrated that organic N is an important source of the nutrient to complement preplant applications in summer squash.

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Petiole sap NO3-N testing as a method for monitoring nitrogen nutrition of potato crops

Canadian Journal of Plant Science ◽

10.4141/p96-091 ◽

1997 ◽

Vol 77 (2) ◽

pp. 273-278 ◽

Cited By ~ 12

Author(s):

D. Waterer

Keyword(s):

Dry Matter ◽

Nitrogen Nutrition ◽

Growing Season ◽

Fertilizer Application ◽

N Fertilizer ◽

Split Application ◽

Potato Crops ◽

Fertilizer Rates ◽

Petiole Sap ◽

N Status

Petiole sap NO3-N concentrations were tested as a means for monitoring crop nitrogen (N) status and N fertilizer responses in potatoes. An ion specific electrode was used to monitor sap NO3-N concentrations of three varieties of potatoes grown with differing amounts of N fertilizer in 1993–1995. Plots provided with varying amounts of fertilizer N applied prior to planting or as a split application were sampled on six occasions through the growing season. Sap NO3-N levels were positively correlated with petiole dry matter NO3-N levels. Petiole sap NO3-N levels reflected rates and timing of N fertilizer application. Sap NO3-N levels in the three cultivars showed similar changes with time after planting and increasing N fertilizer rates. However, sap NO3-N levels measured under a particular set of conditions were unique for each cultivar. The correlation between yields and sap NO3-N levels varied with the sampling date and cultivar. Recommendations were developed for critical sap NO3-N concentrations at various stages in the development of the three cultivars. Key words: Ion specific electrode, nitrate, petiole, nitrogen, tissue testing, Solanum tuberosum

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Large Single-head Broccoli Yield as Affected by Plant Density, Nitrogen, and Cultivar in a Plasticulture System

HortTechnology ◽

10.21273/hortsci.19.4.792 ◽

2009 ◽

Vol 19 (4) ◽

pp. 792-795 ◽

Cited By ~ 1

Author(s):

Daniel L. Schellenberg ◽

Anthony D. Bratsch ◽

Zhengxing Shen

Keyword(s):

Plant Density ◽

Agricultural Research ◽

Total Yield ◽

N Fertilizer ◽

Planting Density ◽

Open Market ◽

Fresh Market ◽

Marketable Yield ◽

N Accumulation ◽

Rate Dependent

An open-market window has been identified in Virginia for fall broccoli (Brassica oleracea var. italica). Vegetable producers using plasticulture systems can capitalize on this opportunity by growing broccoli as a second crop after summer vegetables. The objective of this project was to evaluate suitability of two broccoli cultivars, Everest and Gypsy, for the fall production of large single-heads (>6 inches in diameter) for the fresh market. Planting density and rate of nitrogen (N) fertilizer (25, 60, and 100 lb/acre N) effects on yield characteristics were evaluated in a plasticulture system during a 3-year study (2003–05) conducted with broccoli transplants at the Virginia Polytechnic Institute and State University Kentland Agricultural Research Farm near Blacksburg, VA. The percentage of large heads was cultivar, plant density, and N rate dependent. The midseason ‘Gypsy’ produced significantly higher total yield and head weight compared with the early-season ‘Everest’. The optimum density to maximize floret production per area was 12,500 plants/acre and a supplemental N rate of 100 lb/acre. This N rate significantly (P < 0.002) improved marketable yield, large head yield, and leaf N accumulation compared with the lower rates. The data indicate that the feasibility of growing fall broccoli using a plasticulture system depends on the number of large heads produced for the fresh market. This in turn will depend on the choice of cultivar, stand establishment, and the requirement for supplemental N fertilizer over the residual level available in the soil after the first crop.

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Effects of Preplant Nitrogen and Sulfur Fertilizer Sources on Strawberry

HortTechnology ◽

10.21273/horttech.20.1.193 ◽

2010 ◽

Vol 20 (1) ◽

pp. 193-196 ◽

Cited By ~ 2

Author(s):

Bielinski M. Santos

Keyword(s):

Ammonium Sulfate ◽

Nitrate Leaching ◽

Total Yield ◽

Sandy Soils ◽

Field Studies ◽

Fruit Weight ◽

Growth And Yield ◽

Appropriate Use ◽

Leaching Potential ◽

Marketable Fruit

Field studies were conducted to determine effects of preplant nitrogen (N) and sulfur (S) sources on ‘Strawberry Festival’ strawberry (Fragaria ×ananassa) growth and yield. Six treatments resulted from the preplant application of ammonium nitrate [AN (34% N)], ammonium sulfate [AS (21% N and 24% S)], ammonium sulfate nitrate [ASN (26% N and 14% S)], polymer-coated AS [PCAS (20% N and 23% S)], and elemental S (90% S). A nontreated control was added. The N was fixed at 50 lb/acre for AN, AS, ASN, and PCAS, which resulted in S rates of 0, 57, 27, and 57 lb/acre, respectively. The S rate of the elemental S treatment was set at 57 lb/acre. For early fruit number, the highest values were found in plots treated with AS and elemental S, while the highest total fruit numbers were obtained in plots treated with AS, ASN, PCAS, and elemental S. There was no difference in total fruit numbers between the nontreated control and AN. Plots treated with elemental S, PCAS, ASN, and AS had the highest early marketable fruit weights, whereas the lowest early marketable fruit weight was found in the nontreated plots. In comparison with the nontreated control plots, all the preplant fertilization programs improved early marketable fruit weight, with AN, AS, ASN, PCAS, and elemental S. Total marketable fruit weights were maximized in plots treated with preplant AS, ASN, PCAS, or elemental S. There was no difference between the total fruit weights obtained in the control and AN-treated plots. The data indicated that the strawberry total yield increases can be attributed to the use of preplant fertilizer sources containing S. This research may lead to a more appropriate use of N for strawberry production in Florida, minimizing the nitrate-leaching potential in high sandy soils by eliminating N sources from preplant fertilization programs.

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Carbon and Nitrogen Reserves in Perennial Strawberry Affect Plant Growth and Yield

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.133.6.735 ◽

2008 ◽

Vol 133 (6) ◽

pp. 735-742 ◽

Cited By ~ 3

Author(s):

Laura Elisa Acuña-Maldonado ◽

Marvin P. Pritts

Keyword(s):

Foliar Application ◽

Growing Season ◽

Plant Size ◽

Early Spring ◽

Growth And Yield ◽

N Application ◽

N Content ◽

Total N ◽

Carbohydrate Concentration ◽

Foliar Urea

Early spring growth of perennial strawberry (Fragaria ×ananassa Duch.) plants is supported by the carbohydrate and nitrogen (N) reserves accumulated from the previous growing season. The limitations of these reserves on the initial spring growth and yield of perennial strawberries have not been studied in detail, particularly the influence of N reserves. Differential N fertigation (0 to 20 mm N) was applied to potted strawberries during the growing season and a supplemental foliar urea application was applied to a portion of the plants in the fall to modify reserve N during dormancy. Plant N content and spring vegetative growth the year after fertigation increased nearly twofold with increasing N fertigation. Photosynthesis per unit leaf area also increased up to 10 mm of fertilizer N and then stabilized through 20 mm. Foliar urea application in fall further increased total plant N content and size, decreased carbohydrate concentration, and also decreased yield in plants with the most total N. Nitrogen fertigation was resumed on a portion of these plants in early spring, but new growth and subsequent yield were unaffected by spring N application. In a second experiment, CO2 enrichment with and without soil and foliar N application in the fall was used to vary carbon (C) and N reserves. CO2 enrichment in fall increased plant size and yield the next July by ≈20%, but total nonstructural carbohydrate and N concentrations were unaffected. Foliar urea application also increased N and C reserves (but not concentration) as well as yield in both enriched and unenriched plants. Although foliar urea in fall decreased carbohydrate concentration, total reserve levels were unaffected because treated plants were larger. In this experiment, spring N increased plant size by ≈50%, but yield was increased only 12%, suggesting that yields are mostly dependent on reserves. Increasing N reserves with a late fall foliar application is one strategy growers can use to efficiently enhance growth and yield in low to moderately fertilized plants.

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Nitrogen Fertigation Rates Affect Stored Nitrogen, Growth, and Blooming in Iris germanica ‘Immortality’

HortScience ◽

10.21273/hortsci.51.2.186 ◽

2016 ◽

Vol 51 (2) ◽

pp. 186-191 ◽

Cited By ~ 1

Author(s):

Xiaojie Zhao ◽

Guihong Bi ◽

Richard L. Harkess ◽

Jac J. Varco ◽

Tongyin Li ◽

...

Keyword(s):

Plant Height ◽

Dry Weight ◽

Growing Season ◽

N Fertilizer ◽

N Content ◽

Total N ◽

N Concentration ◽

Inflorescence Stems ◽

Iris Germanica ◽

N Rates

Tall bearded (TB) iris (Iris germanica L.) has great potential as a specialty cut flower due to its fragrance and showy, multicolor display; however, limited research has been reported on optimal nitrogen (N) nutrient management for TB iris. The objectives of this study were to investigate the effects of N fertilizer rate on plant growth and flowering of ‘Immortality’ iris and determine the influence of both stored N and spring-applied N fertilizer on spring growth and flowering. On 14 Mar. 2012, rhizomes of ‘Immortality’ iris were potted in a commercial substrate with no starter fertilizer. Plants were fertigated with 0, 5, 10, 15, or 20 mm N from NH4NO3 twice per week from 28 Mar. to 28 Sept. 2012. In 2013, half of the plants from each of the 2012 N rate were supplied with either 0 or 10 mm N from 15NH415NO3 twice per week from 25 Mar. to 7 May 2013. Growth and flowering data including plant height, leaf SPAD, number of fans and inflorescence stems, and length of inflorescence stem were collected during the growing season. Plants were harvested in Dec. 2012 and May 2013 to measure dry weight and N concentration in leaves, roots, and rhizomes. Results showed higher 2012 N rates increased plant height, leaf SPAD reading, and number of inflorescence stems at first and second blooming in 2012. Greater 2012 N rates also increased plant dry weight and N content in all structures, and N concentration in roots and rhizomes. Rhizomes (58.8% to 66.3% of total N) were the dominant sink for N in Dec. 2012. Higher 2012 N rates increased plant height, number of fans, and the number of inflorescence stems at spring bloom in 2013. In May 2013, N in leaf tissue constituted the majority (51% to 64.3%) of the total plant N. Higher 2012 N rates increased total dry weight, N concentration, and N content in all 2013 15N rates; however, leaf dry weight in all plants was improved by 2013 15N rate. Percentage of tissue N derived from 2013 15N (NDFF) decreased with increasing 2012 N rate. New spring leaves were the dominant sink (56.8% to 72.2%) for 2013 applied 15N. In summary, ‘Immortality’ iris is capable of a second blooming in a growing season, this second blooming dependent on N fertilization rate in current year. A relatively high N rate is recommended to produce a second bloom.

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An Innovative Application of MEISTER (Polyolefin-coated Urea) to Strawberry Pots to Supply N for the Whole Growing Season in Kumamoto, South Japan

HortScience ◽

10.21273/hortsci.31.4.663d ◽

1996 ◽

Vol 31 (4) ◽

pp. 663d-663

Author(s):

K. Takamori ◽

T. Ishida ◽

S. Miyoshi ◽

K. Ayama ◽

T. Higashi

Keyword(s):

Growing Season ◽

N Fertilizer ◽

Experimental Results ◽

New Method ◽

Single Application ◽

Greenhouse Soil ◽

Total N ◽

Coated Urea ◽

Soil Volume ◽

Experimental Plots

A hundred days and 240 days are required for growing strawberry plants in the nursery and in the greenhouse, respectively. Therefore, fertilization using conventional fertilizers is often repeated. To eliminate repeated topdressing, to decrease the amount of N to apply, and to save farming labor, a new fertilization method using MEISTER was studied. Since MEISTER is an excellent controlled fertilizer, the new method can apply all N necessary to grow strawberry plants almost for a year only by a single application (no N fertilizer is applied to the greenhouse soil). The experimental plots basically consist of two kinds of treatment: changing ratios of soil volume per pot or per plant (50 to 800 ml/pot) and kinds and levels of fertilizers (conventional fertilizer and two kinds of MEISTER). The experimental results showed 1) soil of ≥200 ml/pot is necessary to grow strawberry seedlings in summer when the soil is subjected to drying, 2) a blended material of two MEISTER products with sigmoid dissolution can supply N for the whole growing season, and 3) MEISTER application can reduce 40% of the total N conventionally applied.

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