scholarly journals Nitrogen Sources and Rates for Direct-seeded and Transplanted Head Lettuce

HortScience ◽  
1992 ◽  
Vol 27 (3) ◽  
pp. 228-230 ◽  
Author(s):  
J.L. Walworth ◽  
D.E. Carling ◽  
G.J. Michaelson
Keyword(s):  
Nitrogen Sources ◽  
Growing Season ◽  
Field Trials ◽  
Planting Dates ◽  
N Application ◽  
Planting Methods ◽  
Application Rates ◽  
Head Weight ◽  
Southcentral Alaska ◽  
Direct Seeded

Head lettuce (Lactuca sativa L.) cv. Salinas was produced in field trials in southcentral Alaska with varying planting dates, planting methods, N sources, and N application rates. Variables measured included head weight and diameter and harvest date. Nitrogen source had little effect on head weight. Direct-seeded lettuce produced heaviest beads from early plantings; transplants produced heaviest heads when planted in mid- to late season. Transplanting generally produced heavier heads than direct-seeding. Head weight of transplanted and direct-seeded lettuce was maximized with ≈112 kg N/ha. The data suggest that 112 kg N/ha may be suitable for lettuce direct-seeded or transplanted throughout the growing season.

scholarly journals Seasonal Nitrogen Partitioning and Nitrogen Uptake of Carrots as Affected by Nitrogen Application in a Mineral and an Organic Soil

HortScience ◽  
2006 ◽  
Vol 41 (5) ◽  
pp. 1332-1338 ◽  
Author(s):  
Sean M. Westerveld ◽  
Alan W. McKeown ◽  
Mary Ruth McDonald
Keyword(s):  
N Uptake ◽  
Mineral Soil ◽  
Growing Season ◽  
Organic Soil ◽  
Nitrogen Partitioning ◽  
N Budget ◽  
N Application ◽  
Total N ◽  
Application Rates ◽  
N Removal

An understanding of nitrogen (N) uptake and the partitioning of N during the season by the carrot crop (Daucus carota subsp. sativus [Hoffm.] Arkang.) is required to develop more efficient N fertilization practices. Experiments were conducted on both organic and mineral soils to track the accumulation of dry matter (DM) and N over the growing season and to develop an N budget of the crop. Treatments included two carrot cultivars (`Idaho' and `Fontana') and 5 N rates ranging from 0% to 200% of the provincial recommendations in Ontario. Foliage and root samples were collected biweekly from selected treatments during the growing season and assessed for total N concentration. Harvest samples were used to calculate N uptake, N in debris, and net N removal values. Accumulation of DM and N in the roots was low until 50 to 60 days after seeding (DAS) and then increased linearly until harvest for all 3 years regardless of the soil type, cultivar, and N rate. Foliage dry weight and N accumulation were more significant by 50 to 60 DAS, increased linearly between 50 and 100 DAS, and reached a maximum or declined slightly beyond 100 DAS in most cases. The N application rates required to maximize yield on mineral soil resulted in a net loss of N from the system, except when sufficient N was available from the soil to produce optimal yield. On organic soil, a net removal of N occurred at all N application rates in all years. Carrots could be used as an N catch crop to reduce N losses in a vegetable rotation in conditions of high soil residual N, thereby improving the N use efficiency (NUE) of the crop rotation.

Yield parameters of Beta beets as a basis to estimate the biogas yield

2014 ◽  
pp. 169-176 ◽  
Author(s):  
Philipp Starke ◽  
Christa Hoffmann
Keyword(s):  
Sugar Beet ◽  
Dry Matter ◽  
Field Trials ◽  
Sugar Yield ◽  
Dry Matter Yield ◽  
N Application ◽  
Fodder Beet ◽  
Biogas Yield ◽  
Application Rates ◽  
N Rates

High biogas yields are expected from sugar beet because of its high root yield. But it has not been analysed yet, which varieties are best suited to reach the highest biogas yield. The study thus aimed at identifying a parameter to estimate the biogas yield of sugar beet. To get a broad variation of yields and beet qualities, field trials were conducted from 2008 to 2011 at 2 sites (Göttingen and Regensburg, Germany) with different sugar beet varieties and fodder beet. Different N application rates were included and furthermore, autumn sown beets (winter beet). Dry matter composition was analyzed, biogas yield and methane concentration were determined in batch experiments. Sugar beet reached root dry matter yields of more than 20tha–1 and thereby exceeded fodder beet. Moderate N application increased root dry matter yield, whereas higher N rates only enhanced the leaf dry matter yield. But most likely, leaves will not be considered for fermentation because of their low concentration of dry matter and organic dry matter. Winter beet reached total dry matter yields of 12tha–1, but dry matter was not as easily digestible as that of spring sown beets. Biogas yield showed a close linear relation to the root dry matter and the sugar yield as well. Sugar beet varieties can therefore be assessed for anaerobic digestion by their sugar yield. As sugar yield is already the main target, breeding for biogas beets will not be substantially different from that for beets used for sugar manufacture.

scholarly journals Root Distribution and Yield of Direct Seeded and Transplanted Watermelon

1999 ◽  
Vol 124 (5) ◽  
pp. 458-461 ◽  
Author(s):  
D.S. NeSmith
Keyword(s):  
Root Length ◽  
Root Distribution ◽  
Root Length Density ◽  
Citrullus Lanatus ◽  
Growing Season ◽  
Soil Cores ◽  
Marketable Yield ◽  
Stand Establishment ◽  
Planting Methods ◽  
Direct Seeded

Transplanting generally results in more rapid stand establishment than direct seeding for cucurbit crops. A 2-year field study was conducted to examine the pattern of rooting of watermelon [Citrullus lanatus (Thunb.) Matsum. & Nak.] following usage of different planting methods, and to determine subsequent effects on crop yield. Root length was assessed by obtaining soil cores three times per growing season to a depth of 75 cm. Transplanted watermelons generally had greater root length density in the upper 30 cm of soil 4 to 7 weeks after planting (WAP). However, by 11 to 12 WAP root distribution was similar over the entire 75 cm soil profile for the two planting methods. Total marketable yields were comparable for direct seeded and transplanted watermelons during 1995, but transplanted watermelon yield exceeded direct seeded yield by 40% in 1996. In both years, 90% to 100% of the marketable yield of transplanted watermelons was obtained at the first harvest, compared to 0% to 55% for direct seeded watermelons. These findings suggest that rapid root proliferation of transplanted watermelons may be an important factor in their earlier establishment and increased early yields as compared to direct seeded watermelons.

Mesotrione Activity on Crabgrass (Digitariaspp.) as Influenced by Nitrogen Fertilization Rate, Source, and Timing

2015 ◽  
Vol 29 (2) ◽  
pp. 263-273
Author(s):  
Leslie L. Beck ◽  
Aaron J. Patton ◽  
Quincy D. Law ◽  
Daniel V. Weisenberger ◽  
James T. Brosnan ◽  
...  
Keyword(s):  
Nitrogen Concentration ◽  
Field Trials ◽  
Fertilization Rate ◽  
Weed Species ◽  
N Application ◽  
Application Timing ◽  
N Source ◽  
Application Rates ◽  
Herbicide Activity ◽  
Large Crabgrass

Mesotrione, a 4-hydroxyphenylpyruvate dioxygenase-inhibiting herbicide, is labeled for PRE and POST crabgrass control. It has enhanced efficacy on smooth and large crabgrass when applied in conjunction with soil-applied nitrogen (N). The objectives of this study, using crabgrass as the weed species, were to (1) determine the influence of N rate and tissue N concentration on mesotrione activity, (2) determine the influence of N source on mesotrione activity, and (3) determine the influence of N application timing on mesotrione activity. Large crabgrass plants that received 12 kg N ha−1or more before mesotrione application had more bleached and necrotic leaves compared with plants that received 0 kg N ha−17 d after treatment (DAT) in the greenhouse. Although N application rates as high as 98 kg N ha−1were tested, 90% leaf bleaching and necrosis were observed with rates of 8.9 or 10.1 kg N ha−1in Tennessee and Indiana, respectively. Nitrogen concentration in large crabgrass leaf and stem tissue on the day of the mesotrione application was closely related to the bleaching and necrosis symptoms observed 7 DAT. Although N rate influenced mesotrione activity, N source did not. Nitrogen application timing was also important, with N applications 3, 1, and 0 d before a mesotrione application having the highest percentage of bleached and necrotic leaves in greenhouse experiments. Both greenhouse and field trials support the finding that N applications in proximity to the mesotrione application enhance herbicide activity. Thus, practitioners can pair N and POST mesotrione applications together or in proximity to enhance crabgrass control.

scholarly journals Sweetcorn production from transplants

2007 ◽  
Vol 13 (2) ◽  
Author(s):  
F. Orosz ◽  
K. Slezák
Keyword(s):  
Sweet Corn ◽  
New Products ◽  
Early Period ◽  
Growing Season ◽  
Negative Influence ◽  
Planting Dates ◽  
Early Season ◽  
Growing Period ◽  
Early Ripening ◽  
Direct Seeded

In our trial we tried to find out how the time of propagation and transplanting influenced the growing season of sweet corn along with some major properties relevant to quality. The following technological variations were compared with the help of the variety Spirit (normal sweet, very early ripening): transplanted plants with floating row cover (with 2 planting dates); transplanted plants with no row cover: direct seeded plants with no row cover. The 21 day transplant growing period reduced the growing period by 16 to 20 days, compared to the technology used in the existing practice of production. Earliness had a negative influence on ear size, nonetheless it is worth while to attempt since the market is not so exacting with new products in the early period. Covering the seedlings in the early season was clearly beneficial, as the floating row cover provided protection for plants against lower night temperatures which are common in this period.

Considerations for the mitigation of nitrate contamination: stable isotopes and insights into the importance of soil processes

2011 ◽  
Vol 64 (6) ◽  
pp. 1254-1260 ◽  
Author(s):  
George H. Somers ◽  
Martine M. Savard
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Nutrient Management ◽  
Growing Season ◽  
Fertilizer Application ◽  
Nitrate Contamination ◽  
N Application ◽  
Application Rates ◽  
Direct Leaching ◽  
The Impact

Nutrient management is widely promoted to minimize the impact of intensive fertilizer use on groundwater quality, however watershed-scale stable isotope studies in eastern North America suggest nitrogen transport to groundwater is dominated by non-growing season fluxes derived principally from the mineralization and nitrification of soil organic matter. In the current field scale study, δ15N ratios of nitrate in tile drain effluents from experimental potato plots treated with 300 kg/ha ammonia nitrate and those with no fertilizer both average +4.7‰, close to the +4.0‰ ratios observed in soils of the same plots, and distinct from values near 0‰ for inorganic fertilizer. A source apportionment model using δ15N and δ18O in nitrate suggests that even with heavy fertilizer application, less than 10% of non-growing season N flux is derived from direct leaching of fertilizer, the remainder representing N from various sources, including residual fertilizer that has been assimilated into the broader soil organic matter pool and subsequently released via mineralization and nitrification. Factors controlling these losses could be as closely related to cropping practices as initial N application rates, providing potential opportunities for more efficiently utilizing N available in the soil profile and reducing initial N application rates.

scholarly journals Effects of nitrogen on accumulation and partitioning of dry matter and nitrogen of vegetables. 2. Leek

1995 ◽  
Vol 43 (4) ◽  
pp. 435-446
Author(s):  
H. Biemond
Keyword(s):  
Leaf Age ◽  
Field Trials ◽  
N Accumulation ◽  
N Application ◽  
Total N ◽  
Plant Parts ◽  
Time Of Application ◽  
Application Rates ◽  
Fertilizer Rates ◽  
Final Harvest

Two greenhouse and 2 field trials were carried out on leeks cv. Albana with different N fertilizer rates and application dates. Observations included frequent measurements of DM and N accumulation in leaf blades, leaf sheaths and, if present, scapes. Both the amount of N applied and the time of application affected the total accumulation of DM and N in the plant. The relative partitioning rates of DM increase to the shaft were affected in such a way that the final harvest indices for DM (which ranged from 0.32 to 0.53) were significantly lower at higher N application rates. The final harvest indices for N (0.21-0.35) were not significantly affected by amount or timing of fertilizer applications. The total N concentrations of leaf blades and leaf sheaths decreased with increasing leaf age. Average nitrate N concentrations over all plant parts were always below 40%.

scholarly journals Title Exploring the Impacts of Genotype-Management-Environment Interactions on Wheat Productivity, Water Use Efficiency, and Nitrogen Use Efficiency under Rainfed Conditions

Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2310
Author(s):  
Raheel Osman ◽  
Muhammad Naveed Tahir ◽  
Syed Tahir Ata-Ul-Karim ◽  
Wajid Ishaque ◽  
Ming Xu
Keyword(s):  
N Uptake ◽  
Weather Conditions ◽  
Growing Season ◽  
Wheat Cultivars ◽  
N Application ◽  
Application Rates ◽  
Rainfed Conditions ◽  
Use Efficiency ◽  
Crop N Uptake ◽  
N Use

Wheat production under rainfed conditions is restrained by water scarcity, elevated temperatures, and lower nutrient uptake due to possible drought. The complex genotype, management, and environment (G × M × E) interactions can obstruct the selection of suitable high yielding wheat cultivars and nitrogen (N) management practices prerequisite to ensure food security and environmental sustainability in arid regions. The agronomic traits, water use efficiency (WUE), and N use efficiencies were evaluated under favorable and unfavorable weather conditions to explore the impacts of G × M × E on wheat growth and productivity. The multi-N rate (0, 70, 140, 210, and 280 kg N ha−1) field experiment was conducted under two weather conditions (favorable and unfavorable) using three wheat cultivars (AUR-809, CHK-50, and FSD-2008) in the Pothowar region of Pakistan. The experiments were laid out in randomized complete block design (RCBD), with split plot arrangements having cultivars in the main plot and N levels in the subplot. The results revealed a significant decrease in aboveground biomass, grain yield, crop N-uptake, WUE, and N use efficiency (NUE) by 15%, 22%, 21%, 18%, and 8%, respectively in the unfavorable growing season (2014–2015) as compared to favorable growing season (2013–2014) as a consequence of less rainfall and heat stress during the vegetative and reproductive growth phases, respectively. FSD-2008 showed a significantly higher aboveground biomass, grain yield, crop N-uptake, WUE, and NUE as compared to other wheat cultivars in both years. Besides, N140 appeared as the most suitable dose for wheat cultivars during the favorable growing season. However, any further increase in N application rates beyond N140 showed a non-significant effect on yield and yield components. Conversely, the wheat yield increased significantly up to 74% from N0 to N70 during the unfavorable growing season, and there was no substantial difference between N70–N280. The findings provide opportunities for maximizing yield while avoiding excessive N loss by selecting suitable cultivars and N application rates for rainfed areas of Pothowar Plateau by using meteorological forecasting, amount of summer rainfall, and initial soil moisture content.

scholarly journals Effect of different soil and weather conditions on efficacy, selectivity and dissipation of herbicides in sunflower

2020 ◽  
Vol 66 (No. 9) ◽  
pp. 468-476
Author(s):  
Miroslav Jursík ◽  
Martin Kočárek ◽  
Michaela Kolářová ◽  
Lukáš Tichý
Keyword(s):  
Cation Exchange Capacity ◽  
Chenopodium Album ◽  
Soil Layer ◽  
Weather Conditions ◽  
Growing Season ◽  
Application Rate ◽  
Exchange Capacity ◽  
Vertical Transport ◽  
Application Rates ◽  
High Precipitation

Six sunflower herbicides were tested at two application rates (1N and 2N) on three locations (with different soil types) within three years (2015–2017). Efficacy of the tested herbicides on Chenopodium album increased with an increasing cation exchange capacity (CEC) of the soil. Efficacy of pendimethalin was 95%, flurochloridone and aclonifen 94%, dimethenamid-P 72%, pethoxamid 49% and S-metolachlor 47%. All tested herbicides injured sunflower on sandy soil (Regosol) which had the lowest CEC, especially in wet conditions (phytotoxicity 27% after 1N application rate). The highest phytotoxicity was recorded after the application of dimethenamid-P (19% at 1N and 45% at 2N application rate). Main symptoms of phytotoxicity were leaf deformations and necroses and the damage of growing tips, which led to destruction of some plants. Aclonifen, pethoxamid and S-metolachlor at 1N did not injure sunflower on the soil with the highest CEC (Chernozem) in any of the experimental years. Persistence of tested herbicides was significantly longer in Fluvisol (medium CEC) compared to Regosol and Chernozem. Dimethenamid-P showed the shortest persistence in Regosol and Chernozem. The majority of herbicides was detected in the soil layer 0–5 cm in all tested soils. Vertical transport of herbicides in soil was affected by the herbicide used, soil type and weather conditions. The highest vertical transport was recorded for dimethenamid-P and pethoxamid (4, resp. 6% of applied rate) in Regosol in the growing season with high precipitation.  

scholarly journals Dynamics of the Degradation of Acetyl-CoA Carboxylase Herbicides in Vegetables

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 405
Author(s):  
Miroslav Jursík ◽  
Kateřina Hamouzová ◽  
Jana Hajšlová
Keyword(s):  
Linear Models ◽  
Growing Season ◽  
Field Trials ◽  
Baby Food ◽  
Vegetable Production ◽  
The Czech Republic ◽  
Herbicide Residues ◽  
Harvest Intervals ◽  
Small Plot

(1) Background: Aryloxyphenoxy-propionates and cyclohexanediones are herbicides most widely used in dicot crops worldwide. The main objective of the study was to determine the dynamics of herbicide residues in carrot, lettuce, cauliflower, and onion in order to suggest a low level of residues in harvested vegetables. (2) Methods: Small plot field trials were carried out in four vegetables in the Czech Republic. The samples of vegetables were collected continuously during the growing season. Multiresidue methods for the determination of herbicide residues by LC-MS/MS were used. Non-linear models of degradation of individual herbicides in vegetables were calculated using the exponential decay formula. Action GAP pre-harvest intervals for the 25% and 50% maximum residue limit (MRL) and 10 µg kg−1 limit (baby food) were established for all tested herbicides. (3) Results: The degradation dynamics of fluazifop in carrot, onion, and cauliflower was significantly slower compared to quizalofop and haloxyfop. The highest amount (2796 µg kg−1) of fluazifop residues was detected in cauliflower 11 days after application. No residue of propaquizafop and cycloxydim was detected in any vegetable samples. (4) Conclusions: Aryloxyphenoxy-propionate herbicide (except propaquizafop) could contaminate vegetables easily, especially vegetables with a short growing season. Vegetables treated with fluazifop are not suitable for baby food. Lettuce and cauliflower treated by quizalofop are not suitable for baby food, but in onion and carrot, quizalofop could be used. Propaquizafop and cycloxydim are prospective herbicides for non-residual (baby food) vegetable production.

Sign in / Sign up

Export Citation Format

Share Document