Effect of nitrogen fertilization on head size, vitamin C content and storage life of broccoli (Brassica oleracea var. Italica)

1994 ◽  
Vol 74 (3) ◽  
pp. 607-610 ◽  
Author(s):  
Peter M. A. Toivonen ◽  
B. J. Zebarth ◽  
P. A. Bowen

Broccoli quality in British Columbia can vary with season and with the farm site on which it is grown. One major management difference between farms is nitrogen fertilization rate. This work was conducted to determine the effect of nitrogen fertilization (0, 125, 250, 375, 500 and 625 kg N ha−1) and growing season (three plantings in 2 consecutive years) on vitamin C content, head size and storability of broccoli (Brassica oleracea var. Italica, 'Emperor'). The climatic conditions during crop growth and development had a greater overall effect on vitamin C content, head diameter and head weight than nitrogen fertilization. Weight and vitamin C losses during storage in the first year were not affected by nitrogen fertilization rates. Moderate nitrogen application rates of 125 and 250 kg N ha−1 in all three plantings produced a head size considered optimal for marketing. Key words: Postharvest, vegetable quality, climatic conditions

2020 ◽  
Vol 98 (Supplement_2) ◽  
pp. 31-31
Author(s):  
Kevin R Meng ◽  
Eric Bailey ◽  
Josh Zeltwanger ◽  
Hannah Allen ◽  
Mikaela Adams ◽  
...  

Abstract Chemical seed-head suppression of endophyte infected tall fescue (Lolium arundinaceum) improves stocker cattle performance but may decrease forage yield. Spring nitrogen application increases tall fescue growth with a concomitant increase in ergot alkaloids, produced by the symbiotic endophyte Epichloë coenophiala. We hypothesized that greater amounts of nitrogen applied to tall fescue would increase forage yield and offset losses in forage production from chemical suppression of seed-heads with metsulfuron without effect on alkaloid concentration. Ninety-six steers (270 ± 20 kg) were randomly assigned to one of sixteen paddocks (1.8 ha) on April 18 and continuously grazed for 57 d. Paddocks were blocked by previous use (n = 4) and randomly assigned to one of four treatments; no metsulfuron, no nitrogen (NEGCON), metsulfuron with 0 (MET0), 67 (MET67), or 134 (MET134) kg/ha of ammonium nitrate, applied March 11. Steers grazing MET0 paddocks were removed 17 d early due to insufficient forage availability. Steer weight, forage yield, forage nutritive value and ergot alkaloids in forage samples were measured monthly. Seed-head frequency and species composition were determined in June. Metsulfuron application reduced (P < 0.01) tall fescue seed-heads by 80%. Metsulfuron decreased (P = 0.03) ergovaline but ergovaline increased (P < 0.01) at each monthly sampling across treatments. Nitrogen had no impact on ergovaline concentration (P = 0.50). Forage yield tended to be least (P = 0.07) for MET0, intermediate for NEGCON and MET67, and tended to be greatest for MET134 (P = 0.08). Steer ADG was not affected by treatment (P < 0.80). Metsulfuron decreased NDF (P=0.02) regardless of fertilization rate. Forage CP increased with fertilization (P < 0.01) and no differences were detected between NEGCON and MET0 (P = 0.45). Species composition was not impacted (P >0.07) by treatment. Metsulfuron decreased seed-head growth and ergovaline concentration in tall fescue. Additional nitrogen fertilizer ameliorated forage yield lost to metsulfuron application but did not impact steer gain.


2013 ◽  
Vol 33 (1) ◽  
pp. 51-58
Author(s):  
Emilia Mokrzecka

The effect of fertilization of savoy with (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub>, Ca(NO<sub>3</sub>)<sub>2</sub>, NH<sub>4</sub>NO<sub>3</sub> and CO(NH<sub>2</sub>)<sub>2</sub> on the crop, vitamin C content and carbohydrates content was investigated in a pot experiment. The largest crop and the lowest vitamin C content was found with Ca(NO<sub>3</sub>)<sub>2</sub>. The plants fertilized with CO(NH<sub>2</sub>)<sub>2</sub> showed the highest content of carbohydrates.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kailou Liu ◽  
Jiangxue Du ◽  
Yijun Zhong ◽  
Zhe Shen ◽  
Xichu Yu

AbstractNutrient-deficient red soil found in the southern region of China is increasingly being used for potato crops to meet the demand for this staple food. The application of nitrogen fertilizer is necessary to support the production of higher tuber yields; however, the links between nitrate nitrogen and the nitrogen balance in red soil are unknown. A field experiment was conducted in Jiangxi Province in 2017 and 2018 to determine the effects of different nitrogen application rates, 0 kg ha−1 (N0), 60 kg ha−1 (N60), 120 kg ha−1 (N120), 150 kg ha−1 (N150), 180 kg ha−1 (N180), 210 kg ha−1 (N210), and 240 kg ha−1 (N240, the highest rate used by local farmers), on potatoes growing in red soil. Data on tuber yield, crop nitrogen uptake, and the apparent nitrogen balance from the different treatments were collected when potatoes were harvested. Additionally, the content and stock of nitrate nitrogen at different soil depths were also measured. Nitrogen fertilization increased tuber yield but not significantly at application rates higher than 150 kg ha−1. We estimated that the threshold rates of nitrogen fertilizer application were 191 kg ha−1 in 2017 and 227 kg ha−1 in 2018, where the respective tuber yields were 19.7 and 20.4 t ha−1. Nitrogen uptake in potato in all nitrogen fertilization treatments was greater than that in N0 by 61.2–237% and 76.4–284% in 2017 and 2018, respectively. The apparent nitrogen surplus (the amount of nitrogen remaining from any nitrogen input minus nitrogen uptake) increased with increasing nitrogen application rates. The nitrate nitrogen stock at a soil depth of 0–60 cm was higher in the 210 and 240 kg ha−1 nitrogen rate treatments than in the other treatments. Moreover, double linear equations indicated that greater levels of nitrogen surplus increased the nitrate nitrogen content and stock in soils at 0–60 cm depths. Therefore, we estimate that the highest tuber yields of potato can be attained when 191–227 kg ha−1 nitrogen fertilizer is applied to red soil. Thus, the risk of nitrate nitrogen leaching from red soil increases exponentially when the apparent nitrogen balance rises above 94.3–100 kg ha−1.


2001 ◽  
Vol 81 (4) ◽  
pp. 765-772 ◽  
Author(s):  
C. Bélec ◽  
S. Villeneuve ◽  
J. Coulombe ◽  
N. Tremblay

This study, spanning 2 yr at two different sites, compared the effects of nitrogen fertilization on broccoli yield and quality in relation to the influence of site and production season. This research also evaluated the potential use of measuring nitrate in petiole extracts to determine broccoli nitrogen requirements when making a second fertilizer application 5 wk after transplant. Treatments consisted of factorial combinations of three nitrogen fertilization rates at transplant (Nmin, 50-Nmin and 100-Nmin kg N ha–1, where Nmin was the soil nitrate concentration) and four nitrogen fertilization rates 5 wk after transplant (0, 50, 100 and 150 kg N ha–1). The marketable yield of broccoli increased with the rate of nitrogen application. Hollow stem incidence showed the same trend as yield, and was greatest when high levels of nitrogen were applied 5 wk after transplant. Interactions between the 5-wk nitrogen application and production year, as well as growing site were significant. The nitrate content of the sap was measured immediately before the 5-wk nitrogen application and 2 wk later. The nitrate concentration measured at 5 wk increased with transplant nitrogen, as did the concentration measured at 7 wk. Nitrate concentration at 7 wk increased curvilinearly with the 5-wk fertilizer application rates. Sap analysis provided clear evidence of the effect of nitrogen application rates, but Environment precluded determination of an absolute threshold of nitrate sufficiency in the sap. Key words: Brassica oleracea L. var. Italica, split application, quality, environment


Author(s):  
Jana Matějková ◽  
Kristína Petříková

This work give results from analyses of variety, growing site, year and storage influence on the ascorbic acid content by selected vegetables: carrot (Daucus carota L.), parsley (Petroselinum crispum Nyman ex A. W. Hill), onion (Allium cepa L.), garlic (Allium sativum L.) and leek (Allium porrum L.). The evaluation carried on during the years 2004 to 2006.The variety influence on ascorbic acid was statistically significant by carrot, parsley root and also parsley leaves and by garlic. In carrots had late varieties Olympia and Tinga significant higher vitamin C content (more than over 60 %) compared to early to half-late varieties Delicia, Kráska, Stupická and Nerac F1. The growing site influence was significant only by parsley leaves and onion. The influence of the growing year was one of the most important factors, which influenced vitamin C contents in selected vegetables – except of carrot was this factor statistically significant by all sorts. Changes in vitamin C content in growing years were induced above all by different climatic conditions (temperatures and rainfall courses). Higher ascorbic acid content was by garlic in the year 2005, when lower tem­pe­ra­tu­res during July were noted compared to year 2004. In parsley root and leaves, onion and leek was noted higher ascorbic acid content in year 2005, when average temperatures in August were as far as 2°C lower than in year 2004. In the case of leek could the increase of ascorbic acid in year 2005 result also from minimal rainfall during October in comparison with October 2004. By all storaged vegetables was noted statistically significant decrease of vitamin C after 30-days storage. The losses of vitamin C were highest in carrot (45 %), followed by parsley (25 %), garlic (24 %) and onion (22 %).Vitamin C content was the highest by parsley leaves (1692 mg . kg−1), parsley contained high vitamin C amounts also in root (515 mg . kg−1). Leek varieties contained 281 to 297 mg . kg−1 of vitamin C, garlic varieties 105 to 132 mg . kg−1, onion varieties 94 to 104 mg . kg−1 and carrot varieties 58 to 117 mg . kg−1 vitamin C.


Author(s):  
C deRoton ◽  
A Wiernik ◽  
I Wahlberg ◽  
B Vidal

AbstractSeveral trials the results of which are compiled in this paper, were carried out at the Tobacco Institute of Bergerac (ITB) and in the area nearby from 1996 to 2003. The objective was to study the formation of tobacco-specific nitrosamines (TSNA) in dark air-cured and burley tobaccos during curing and post-curing treatment under the conditions of cultivation, curing and storage commonly applied by the growers in the south-western part of France. For experimental purposes special treatments were performed in certain trials.The results showed that the main genetic trait involved in the formation of TSNA is the propensity of a variety to convert nicotine to nornicotine (NN). In addition, the ability of a variety to lose water rapidly limits the formation of nitrite and hence also the formation of TSNA. Furthermore, agricultural practices that led to an increase of alkaloid concentrations in the tobacco leaves also led to an increase of TSNA concentration. Priming, a mode of harvest which speeds up the cure, as compared to stalk-cutting, as well as low temperatures during curing, limit the formation of TSNA, but do not yield tobaccos of the best quality. Ventilation in the barn plays a major role, and the leaves cured in well ventilated curing structures, such as plastic sheds, generally contained smaller amounts of TSNA than leaves cured in a conventional curing barn. The results also indicated that the TSNA concentrations may increase after the end of cure, if the cured tobaccos were kept hanging in the barn under humid conditions. The concentration of TSNA may also continue to increase, whereas nitrite concentrations tend to decrease, when the leaves are kept in bales.It can be concluded that the French climatic conditions with moderate temperatures and low relative humidity at the time of curing, are favourable for the production of air-cured tobaccos with a good quality and low TSNA concentrations (1.5-3.5 µg/g), provided that the variety has low NN content, the nitrogen fertilization is moderate, the curing is performed in a well ventilated environment, the tobacco is taken down and stripped as soon as it is cured, and the bales are stored as briefly as possible before the leaves are threshed and stabilized.


Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3746
Author(s):  
Magdalena Polak-Śliwińska ◽  
Małgorzata Tańska

The benefits of natural honeybee products (e.g., honey, royal jelly, beeswax, propolis, beevenom and pollen) to the immune system are remarkable, and many of them are involved in the induction of antibody production, maturation of immune cells and stimulation of the immune system. The type of plants in the geographical area, climatic conditions and production method have a significantly influence on the nutritional quality of honey. However, this variability can influence consumer liking by the sensory attributes of the product. The aim of this work was to compare the most popular honeys from Poland in terms of nutritional value, organoleptic properties and antioxidant activity. In the study, five varieties of honey (honeydew, forest, buckwheat, linden and dandelion) from conventional and organic production methods were tested. The nutritional characteristics of honey samples included acidity, content of water, sugars, vitamin C, HMF and phenolics (total and flavonoids), while honey color, taste, aroma and consistency were investigated in the organoleptic characteristics. The antioxidant activity was determined in water- and ethanol-soluble honey extracts using DPPH and ORAC tests. The results showed that organoleptic and nutritional characteristics of popular Polish honeys differ significantly in relation to plant source and production method. The significant effect of honey variety on the content of HMF, saccharose and phenolics, as well as acidity and antioxidant capacity were noted. The impact of variety and variety × production method interaction was significant in the case of the content of vitamin C, glucose and fructose. A visible difference of buckwheat and forest honeys from other samples was observed. The highest content of total phenolics with antioxidant activity based on the SET mechanism was found in buckwheat honeys, while forest honeys were richer in flavonoids.


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