PERFORMANCE  OF  BIODEGRADABLE  FLOATING  DIRECT  COVERS   IN  THE  FIELD  PRODUCTION  OF  BUTTERHEAD  LETTUCE  DURING  SPRING  AND  AUTUMN  TRIALS

Non-degradable polypropylene nonwovens are difficult to dispose and their utilization represents high economic costs. This study was conducted on lettuce cultivated during the spring and autumn seasons in the southern part of Poland to test biodegradable nonwovens as plant covers. Several nonwovens were developed from aliphatic-aromatic copolyesters (ACC), one without modifiers (SB48/11) and three with the addition of fatty acid dimers: two commercial variants (SB20/13, SB21/13) and one made from plant biomass (SB28/13). Nonwoven polypropylene (PP) fleece was included as a control cover. One week after covering with SB48/11, stomatal conductance (gs) increased in lettuce plants in parallel with higher transpiration rate (E) and sub-stomatal CO2 concentration (Ci) relative to the control, but differences in these parameters evened out in mature plants. In the spring, degradable covers with their higher mass per unit area, caused a decrease in marketable yield of lettuce compared to the control PP, resulting mainly from the deterioration of plant quality and lower mean weight per head. In the autumn season, yield was statistically not different between treatments. Yield of spring lettuces was 78% higher compared to the autumn cultivation period. Plants grown under SB20/13 had the lowest dry weight and L-ascorbic acid, while plants under SB21/13 had the highest dry weight and L-ascorbic acid content. Plants under SB28/13 had higher chlorophyll a content. Generally, no effect of covers was noted for carotenoid concentrations. The content of dry weight, L-ascorbic acid, and carotenoids were higher in plants harvested in spring, while no effects of crop season on chlorophyll level were observed. All tested biodegradable nonwovens are a potential substitute for standard polypropylene in autumn trials, but for spring covering unit weight of these materials should be reduced.

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Effect of biodegradable nonwoven covers on yield and chemical composition of overwintering onion

Italus Hortus ◽

10.26353/j.itahort/2020.1.4154 ◽

2020 ◽

Vol 27 ◽

pp. 41-54

Author(s):

Andrzej Kalisz ◽

Agnieszka Sękara ◽

Andrzej Jurkow ◽

Aneta Grabowska

Keyword(s):

Ascorbic Acid ◽

Chemical Composition ◽

Open Field ◽

Sugar Content ◽

Ascorbic Acid Content ◽

Dry Weight ◽

Vegetable Crops ◽

Marketable Yield ◽

Total Sugar Content ◽

Onion Bulbs

Floating row covers are important pre-harvest factors for maximizing the yield of vegetable crops grown under open-field conditions. It is necessary to replace oil-based nonwoven covers with biodegradable ones that are environmentally friendly. The aim of this study was to investigate the effects of biodegradable nonwoven covers, made of aliphatic-aromatic copolyesters, with or without fatty acid dimers (SB20/13, SB21/13, and SB28/13), on yield and chemical composition of ‘Glacier’ and ‘Swift’ winter onions. In the first experiment, we observed a higher total marketable yield and higher harvest index for onions covered with SB21/13 (by 24% and 3%, respectively) when compared to the control (polypropylene nonwoven). The SB20/13 cover significantly decreased mean bulb weight by 15.3% than in control. Bulbs harvested from the plots covered with SB21/13 had lower dry weight by 3.2-3.7% and those covered with SB28/13 showed the lowest L-ascorbic acid content when compared to all other treatments (by 6.3-10.3%). The lowest total sugar content was found in control onion bulbs, but it was significantly different only from bulbs covered by SB20/13, which had more sugar by 10.6%. In the second experiment, plants covered with the SB28/13 had a 1 st grade yield of onions higher by 47% than that of the control. The highest mean bulb weight was obtained from plants covered with the SB21/13 nonwoven. Covering with nonwovens caused a decrease in dry weight (SB20/13 and SB21/13, by 1.3-1.7%, respectively) and L-ascorbic acid (all nonwovens, by 15.6% for SB21/13 up to 22% for SB20/13) in onion bulbs in comparison to the control. Since the tested biodegradable nonwovens covers did not cause any decrease in the yield of winter onions compared to polypropylene nonwovens, the former appear to be a suitable environmental-friendly solution for the open-field cultivation of this important vegetable crop.

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The yield and quality of broccoli grown under flat covers with soil mulching

Plant Soil and Environment ◽

10.17221/168/2014-pse ◽

2014 ◽

Vol 60 (No. 5) ◽

pp. 228-233 ◽

Cited By ~ 2

Author(s):

E. Kosterna

Keyword(s):

Ascorbic Acid ◽

Dry Matter ◽

Nutritive Value ◽

Ascorbic Acid Content ◽

Chemical Components ◽

Marketable Yield ◽

Fresh Matter ◽

Organic Mulch ◽

Yield And Quality ◽

Rye Straw

The experiment was carried out between 2010 and 2012. Effect of plants covering and the kind of organic mulch applied to soil mulching on the yield and selected component of nutritive value in Milady F<sub>1</sub> broccoli cultivated for early harvest was investigated. The application of polypropylene fibre contributed to a significant increase in the marketable yield of broccoli on average by 5.25 t/ha, weight of head by 0.10 kg and length of arc by 1.44 cm. Increase of the content of chemical components as a result of plants covering amounted to 1.76% for dry matter, 2.50 mg/100 g fresh matter (FM) for ascorbic acid, 0.65% FM for total sugar and 0.15% FM for monosaccharides. All kinds of straw contributed to an increase in the broccoli yield and improvement its parameters. The highest marketable yield and weight of head was obtained in the plots mulched with buckwheat straw. Irrespective of covering, cultivation on the mulch with buckwheat straw contributed to a slight decrease in dry matter, total sugars content, whereas cultivation on the rye straw decreased ascorbic acid content.

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Composition of Four Potato Cultivars in Relation to Cold Storage and Reconditioning

HortTechnology ◽

10.21273/horttech.5.3.250 ◽

1995 ◽

Vol 5 (3) ◽

pp. 250-253 ◽

Cited By ~ 9

Author(s):

James A. Okeyo ◽

Mosbah M. Kushad

Keyword(s):

Ascorbic Acid ◽

Specific Gravity ◽

Cold Storage ◽

Soluble Protein ◽

Sugar Content ◽

Ascorbic Acid Content ◽

Dry Weight ◽

Total Sugar ◽

The Other ◽

Total Sugar Content

`Atlantic', `BelRus', `Kennebec', and `Superior' potatoes (Solarium tuberosum L.) were evaluated for ascorbic acid, soluble protein, and sugar content (reducing and nonreducing) at harvest, after 6 weeks of storage at 3C, and after 2 weeks of reconditioning at 25C. At harvest, ascorbic acid and soluble protein contents varied among the cultivars, with `Superior' containing the highest ascorbic acid (154 mg/100 g dry weight) and soluble protein content (46.4 mg·g−1 dry weight). Cold storage resulted in a drastic reduction (±50%) in ascorbic acid content in all four cultivars. Ascorbic acid also decreased during reconditioning of tubers, but the reduction was less than during cold storage. In contrast, soluble protein contents were not influenced significantly by cold storage or reconditioning, except for `BelRus' and `Kennebec', which had less protein after reconditioning. At harvest, glucose, fructose, and sucrose contents were at similar levels in all cultivars, except for fructose in `Kennebec', which was more than 2-fold higher. `Kennebec' also had a significantly lower specific gravity than the other cultivars. However, unlike the other cultivars, reconditioning of `Kennebec' tubers did not affect its specific gravity or total sugar content. Data suggest that `Kennebec's' poor processing quality may have resulted from a combination of low specific gravity and high total sugar content.

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Biostimulant Effects of an Aqueous Extract of Duckweed (Lemna minor L.) on Physiological and Biochemical Traits in the Olive Tree

Agriculture ◽

10.3390/agriculture11121299 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1299

Author(s):

Luca Regni ◽

Daniele Del Buono ◽

Begoña Miras-Moreno ◽

Biancamaria Senizza ◽

Luigi Lucini ◽

...

Keyword(s):

Chlorophyll Content ◽

Aqueous Extract ◽

Plant Biomass ◽

Growth Parameters ◽

Lemna Minor ◽

Net Photosynthesis ◽

Dry Weight ◽

Co2 Concentration ◽

Olive Tree ◽

Water Volume

Biostimulants are becoming increasingly popular in agriculture for their ability to induce beneficial effects in crops, paving the way towards the identification of new materials with biostimulant potential. This study evaluated the potential of different concentrations of an aqueous extract (0.25%, 0.50%, and 1.00%, dry weight/water volume, respectively) obtained from duckweed (Lemna minor L.) to stimulate olive plants. Leaf net photosynthesis (Pn), leaf transpiration rate (E), stomatal conductance (gs), sub-stomatal CO2 concentration (Ci), chlorophyll content and other plant growth parameters were investigated. As a result, the extract improved Pn, gs, Ci, chlorophyll content and plant biomass production (leaf fresh and dry weight). Furthermore, the duckweed extract generally increased the uptake of nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe) and zinc (Zn), while it did not influence the content of sodium (Na), manganese (Mn) and copper (Cu). The untargeted metabolomic profiling of the extract revealed the presence of signalling compounds (including phytohormones), phenolics and glutathione. Such broad diversity of bioactives may support the stimulatory potential observed in olive. In summary, this study revealed for the first time that duckweed could be seen as a promising species to obtain extracts with biostimulant properties in olive trees.

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Yield and Nutritional Quality of Vesuvian Piennolo Tomato PDO as Affected by Farming System and Biostimulant Application

Agronomy ◽

10.3390/agronomy9090505 ◽

2019 ◽

Vol 9 (9) ◽

pp. 505 ◽

Cited By ~ 14

Author(s):

Gianluca Caruso ◽

Stefania De Pascale ◽

Eugenio Cozzolino ◽

Antonio Cuciniello ◽

Vincenzo Cenvinzo ◽

...

Keyword(s):

Ascorbic Acid ◽

Organic Acids ◽

Plant Biomass ◽

Protein Hydrolysate ◽

Tomato Fruit ◽

Farming System ◽

Fruit Yield ◽

Soluble Solids ◽

Marketable Yield ◽

Area Index

Scientific investigations are being increasingly devoted to biostimulant effects on vegetable yield and quality, with the perspective of sustainable crop management. Two farming systems (conventional or organic) in factorial combination with two biostimulant treatments (tropical plant extract (PE); legume-derived protein hydrolysate (PH)) plus a non-treated control were compared in terms of tomato fruit yield, yield components, mineral composition, functional and nutritional indicators. PE- and PH-based biostimulants resulted in higher plant biomass, PH even in higher leaf area index, compared to non-treated control. Marketable yield was not significantly affected by farming system. PH and PE gave higher yield than non-treated control. PH treatment led to higher fruit number than the control, whereas PE incurred significant increase in yield only under organic farming. The mean fruit weight attained the highest value upon PE application under conventional management. Colour component a* (redness) was higher with the conventional system compared to the organic one, whereas an opposite trend was shown by the organic acids malate, oxalate and isocitrate. Irrespective of the farming system, the soluble solids, fruit brightness (L*) and redness as well as the target organic acids malate, oxalate, citrate and isocitrate were significantly higher than untreated plants by 10.1%, 16.1%, 19.8%, 18.9%, 12.1%, 13.5% and 26.8%, respectively, with no significant differences between the PH- and PE-based biostimulants. Higher lipophilic activity and total ascorbic acid concentration but lower lycopene were recorded under organic management. PE and PH application resulted in higher total phenol and ascorbic acid as well as in lycopene content, and lipophilic antioxidant activity than the non-treated control. Biostimulants proved to be an effective sustainable tool for enhancing tomato fruit yield and functional quality both under conventional and organic vegetable systems.

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CHANGES IN THE RELATIVE AMOUNTS OF ASCORBIC ACID AND GLYCOGEN IN DENERVATED RAT GASTROCNEMIUS MUSCLE

Canadian Journal of Biochemistry ◽

10.1139/o65-081 ◽

1965 ◽

Vol 43 (6) ◽

pp. 705-710 ◽

Cited By ~ 5

Author(s):

G. L. A. Graff ◽

A. J. Hudson ◽

K. P. Strickland

Keyword(s):

Ascorbic Acid ◽

Muscle Mass ◽

Gastrocnemius Muscle ◽

Glycogen Content ◽

Ascorbic Acid Content ◽

Relative Increase ◽

Unit Weight ◽

Contributory Factor ◽

Denervated Muscle ◽

A Value

In this investigation both ascorbic acid and glycogen were determined in rat gastrocnemius muscle after denervation for times ranging from 12 hours to 60 days. To assess more correctly the changes due to denervation, concentrations per unit weight and content per whole muscle were expressed as a percentage of the corresponding value obtained from the contralateral control. The concentrations of ascorbic acid and glycogen in the normal rat gastrocnemius were, respectively, 2.7 ± 0.1 μg (S.E.M. for 51 animals) and 355 (as a glucose equivalent) ± 15 μg (S.E.M. for 52 animals) per 100 mg wet weight. The concentration of ascorbic acid per unit weight showed significant increase (+ 27%) 36 hours after neurotomy and reached five times the control value 60 days after the denervation. The ascorbic acid content of the whole denervated muscle gradually accumulated to a value of 195% of control at 5 days and then declined to a value of 78% at 15 days and 65% at 60 days. In the later stages of atrophy the losses in ascorbic acid were always less than the losses in muscle mass. The glycogen concentration per unit weight remained essentially unchanged for the first 36–48 hours after neurotomy; it then dropped abruptly to 39% of the original value on the 3rd day and stayed at about this level until the 60th day after denervation. In the first 12 hours there appeared to be a slight rise in the glycogen content of the whole denervated muscle. Subsequently, there was a rapid loss of glycogen from 116% of normal at 24 hours to 35% at 3 days; during the same period of time the loss in muscle mass was only 16%. The loss in glycogen content after 60 days represented 94% of the original amount.The observed initial accumulation of ascorbic acid after denervation may reflect a relative increase in active transport (or in situ synthesis) over breakdown mechanisms. The results reported rule out the possibility that a local deficiency in ascorbic acid per unit weight of muscle is a contributory factor to denervation atrophy and show that there is a continuous local accumulation of ascorbic acid.

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Physiological and biochemical responses of Sorghum vulgare plants to supplemental ultraviolet-B radiation

Canadian Journal of Botany ◽

10.1139/b98-137 ◽

1998 ◽

Vol 76 (7) ◽

pp. 1290-1294 ◽

Cited By ~ 1

Author(s):

Navin Kumar Ambasht ◽

Madhoolika Agrawal

Keyword(s):

Ascorbic Acid ◽

Gas Exchange ◽

Peroxidase Activity ◽

Plant Biomass ◽

Stratospheric Ozone ◽

Ascorbic Acid Content ◽

Ultraviolet B ◽

Sorghum Vulgare ◽

Ultraviolet B Radiation ◽

Physiological And Biochemical

Sorghum (Sorghum vulgare (Pers.) cv. MSH 51) plants were grown in the field under ambient and supplemental levels of ultraviolet-B radiation (UV-B; supplemental daily dose corresponding to a 20% reduction in the stratospheric ozone column). Gas exchange characteristics, biomass, and levels of photosynthetic pigments, flavonoids, catalase, peroxidase activity, and ascorbic acid were determined to evaluate the changes induced by enhanced levels of UV-B irradiation. Gas exchange analysis indicated that one of the reasons for the decline in photosynthesis is stomatal limitation. Enhanced UV-B also caused reductions in chlorophyll and carotenoid pigments after 60 days of exposure. Concentrations of UV-B absorbing pigments increased linearly with age. UV-B irradiation also increased phenolic compounds. Catalase activity decreased, while peroxidase activity increased in response to elevated UV-B. There was a decrease in total plant biomass and ascorbic acid content of plants exposed to UV-B. Thus, an enhanced level of UV-B irradiation over a long period has a cumulative unfavourable effect on a number of physiological and biochemical processes, leading to a reduction in dry matter production.Key words: UV-B radiation, Sorghum vulgare, photosynthesis, stomatal resistance, flavonoids, peroxidase.

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Different Temperature Regimes Influenced the Quality of Broccoli Seedlings, Which Caused a Change in the Chemical Composition of Mature Heads

Agronomy ◽

10.3390/agronomy11091806 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1806

Author(s):

Andrzej Kalisz ◽

Joanna Gil ◽

Edward Kunicki ◽

Agnieszka Sękara ◽

Andrzej Sałata ◽

...

Keyword(s):

Ascorbic Acid ◽

Chemical Composition ◽

Chemical Constituents ◽

Chilling Stress ◽

Soluble Sugars ◽

Ascorbic Acid Content ◽

Dry Weight ◽

Temperature Treatment ◽

Long Term Effects ◽

Low Temperature Treatment

Exposure of vegetable seedlings to lowered temperature affects their growth and the content of certain chemical constituents. Chilling activates defensive mechanisms against stress and leads to acclimatization which increases plant ability to withstand harsh field conditions. Thus, seedlings subjected to low-temperature treatment had altered metabolic pathways, and these changes can persist until harvest. We therefore assessed: (i) the direct response of broccoli seedlings to 1 week or 2 weeks at lowered temperatures (6 °C, 10 °C, 14 °C, and 18 °C—control); and (ii) the long-term effects of the latter treatments on phytochemical components level in mature heads of broccoli cultivated in the field. Chilling stress decreased seedling shoot and root fresh and dry weights, plant height, number of leaves, leaf area, leaf perimeter, and leaf width. The most spectacular reductions in these parameters were observed at 6 °C and 10 °C. Longer exposure to lowered temperature resulted in greater reduction in the values of morphological traits. Chilling led to reduction in L-ascorbic acid content in broccoli seedlings, while a 6 °C temperature caused an increase in soluble sugars. The highest content of dry weight, soluble sugars, and L-ascorbic acid were observed in the heads of plants exposed to 14 °C; however, the content of dry weight (at 10 °C) and L-ascorbic acid (at 6 °C and 10 °C) also increased in broccoli heads in comparison with the control. Longer chilling (for 2 weeks) generally increased the content of these constituents in mature broccoli. Lower temperature (6–14 °C) applied at seedling stage increased P and Zn contents in broccoli heads in comparison to the control, whereas plants treated with 10 °C had more K, Fe, and, together with 6 °C treatment, Cu. The lowest temperature applied to the seedlings (6 °C) caused an increase in Mn content, while no effects of seedling chilling was noted for Ca levels. Significant linear correlations were noted and regression models were developed for the content of dry weight, soluble sugars, and L-ascorbic acid in the broccoli heads based on the chosen seedling parameters. The results show that the effect of lowered temperature to which the seedlings were subjected persists also in the further stages of plant ontogenesis, causing permanent changes in the chemical composition of mature broccoli heads.

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Biochemical, Phytochemical and Antioxidant Analysis of Leaves and Seed of Fenugreek Plant

FRONTIERS IN CHEMICAL SCIENCES ◽

10.52700/fcs.v1i2.8 ◽

2020 ◽

Vol 1 (2) ◽

pp. 9-18

Author(s):

Haq Nawaz ◽

Hina Andaleeb ◽

Sobia Aziz ◽

Saba Rehman

Keyword(s):

Ascorbic Acid ◽

Acid Content ◽

Reducing Sugars ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Reducing Power ◽

Ascorbic Acid Content ◽

Dry Weight ◽

Water Soluble ◽

Total Phenolic

In the present study leaves and seeds of two different varieties of Fenugreek plant viz. Trigonella foenum gracium and Trigonella corniculata, collected from Bahawalpur, Pakistan were subjected to the biochemical, phytochemical and antioxidant analysis. The content of total sugars, non reducing sugars and reducing sugars in selected parts of these varities were found to be 5.007±0.101 to 8.133±0.223, 4.255±0.150 to 7.099±0.316 and 0.751±0.064 to 1.410±0.071 g/100g of dry weight respectively. Water soluble, salt soluble and total salt soluble protein content range from 1.172±0.001 to 6.015±0.132, 1.517±0.038 to 1.174±0.006 and 0.013±0.001 to 0.018±0.001 g/100 g of dry weight respectively and the total free amino acids ranged from 1.198±0.014 to 4.554±0.006 g/100 g of dry weight. The range of tannins and saponin contents in analyzed parts of these varities was found to be 0.057±0.009 to 0.117±0.025 and 0.083±0.012 to 0.0151±0.045 g /100g of dry weight respectively. Similarly, flavonoids and hydrogen cyanide content ranged from 0.021±0.000 to 0.055±0.004 and 0.0234±0.008 to 0.307±0.009 g/100g of dry weight respectively; while ascorbic acid content was found to be in the range of 0.068±0.08 to 0.267±0.031 g/100g of dry weight. Total phenolic acid content of the selected parts of these varities were estimated on the basis of difference in dipole moment and its range was observed from 0.0539±0.024 to 0.856±0.064 g/100g of dry weight. The total antioxidants analysis showed that ascorbic acid and trolox contents (mg Eqv./100g of extract) were found to be lower in Trigonella corniculata seeds (0.066±0.001 and 0.047±0.001 mg Eqv./100g respectively) and higher in Trigonella corniculata leaves (0.069±0.001 and 0.050±0.001 mg Eqv./100g respectively).The DPPH radical scavenging activity and reducing power were found to be in the range of 31.736±2.430 to 39.590±2.432 and 0.974±0.231 to 2.301±0.068 respectively. The different parts of studied varities of fenugreek plant, having higher values of %DPPH inhibition and reducing power showed least count of IC50 and vice versa.

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Yield and quality of bush processing tomatoes fertilized with dried organic and organomineral fertilizers

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun200856020031 ◽

2008 ◽

Vol 56 (2) ◽

pp. 31-38 ◽

Cited By ~ 2

Author(s):

Stanislav Boček ◽

Ivan Malý ◽

Šárka Patočková

Keyword(s):

Ascorbic Acid ◽

Farmyard Manure ◽

Total Yield ◽

Ascorbic Acid Content ◽

Fruit Weight ◽

Mineral Fertilizers ◽

Marketable Yield ◽

Yield And Quality ◽

Processing Tomatoes

The effect of dried organic and organomineral fertilizers on the yield and quality of the bush processing tomatoes variety ‘Proton’ were explored in 2005–2006. Field experimental plots were established in Žabčice in the Czech Republic. The following variants of fertilizers were included: Agormin T, Agro, Dvorecký agroferm, farmyard manure, mineral fertilizers and unfertilized control. All plots, except the control, were fertilized with mineral fertilizers on the same nutrients level. Total yield, marketable yield, number of fruits and mean fruit weight were assessed. Total solids, carotenoids, ascorbic acid and nitrates (mg.kg−1 of fresh fruit weight) were analysed in fruits. Fertilizers did not significantly influence total yield and marketable yield. The highest yields were found at Agormin T (7.42 kg . m−2 and 6.73 kg . m−2, respectively), the highest mean fruit weight was found at mineral fertilizers (82.9 g) and Agormin T (82.4 g). Fertilizing with Agro resulted in the highest number of fruits (81.0 pieces . m−2). Dvorecký agroferm significantly increased ascorbic acid content in fruits compared to the control. The highest nitrates content was recorded for the control, the lowest for mineral fertilizers. There was not found significant effect of fertilizers on total solids and carotenoids. All tested dried organic or organomineral fertilizers were shown to be efficient alternatives to traditional farmyard manure. Only Agro significantly decreased ascorbic acid content in comparison to farmyard manure.

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