Next Article in Journal
Global Trends in the Research and Development of Petrochemical Waste Gas from 1981 to 2022
Previous Article in Journal
The Conceptualization of a Modular Residential Settlement Project Emerging in a Displacement Situation due to War in the Context of Sustainable Development Requirements
Previous Article in Special Issue
Investigation of the Main Parameters Influencing the Kinetics of an Ammonia Stripping Plant Treating Swine Digestate
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Sustainability
Volume 16
Issue 14
10.3390/su16145973
sustainability-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Biodegradable Spray Mulch Applications in Greenhouse Agroecosystems

by
Michele Caputo
1,
Carlo Di Cesare
1,
Paola Iovieno
1,
Barbara Immirzi
2,
Daniela Baldantoni
3,*,
Marija Stipic
1,
Massimo Zaccardelli
1 and
Accursio Venezia
1
1
Council for Agricultural Research and Economics, 84098 Pontecagnano, SA, Italy
2
Institute on Polymers, Composites and Biomaterials, National Research Council, 80078 Pozzuoli, NA, Italy
3
Department of Chemistry and Biology “Adolfo Zambelli”, University of Salerno, 84084 Fisciano, SA, Italy
*
Author to whom correspondence should be addressed.
Sustainability 2024, 16(14), 5973; https://doi.org/10.3390/su16145973
Submission received: 14 June 2024 / Revised: 7 July 2024 / Accepted: 9 July 2024 / Published: 12 July 2024
(This article belongs to the Collection Feature Papers in Sustainable Use of the Environment and Resources)
Browse Figures
Versions Notes

Abstract

:
The replacement of synthetic chemical herbicides and traditional plastic sheets is a major challenge of modern horticulture in view of a sustainable weed management. In the first step of this research, we tested the weed control efficacy of two biodegradable polymers, chitosan and galactomannan, applied to the soil surface as spray mulching, with or without the addition of charcoal as a light masking agent, and five essential oils with recognized herbicide properties. The results showed the ability of chitosan in reducing the number and the biomass of annual plants, regardless of the addition of charcoal and essential oils. In the second step, we tested the efficacy of one or three days of false seeding to increase the effectiveness of chitosan against seed germination. The results showed, on average, a reduction of 79% of annual weed presence after three days of false seeding. In both steps, the microbial biomass and three indicators of microbial activity (i.e., basal respiration, FDA hydrolysis activity, and D-glucosamine-induced respiration) were measured in the soil under the experiments in order to investigate possible alterations of soil biological activity induced by the treatments. The results provided no evidence of negative impact of the treatments on soil microbial biomass and activity.

1. Introduction

Weeds are one of the main problems in agroecosystems because they take up space and other resources from crops, competing for light, water, and nutrients. The main method of struggle adopted in recent decades is the use of synthetic chemicals, such as the herbicide glyphosate, N-(phosphonomethyl)glycine, whose production began in 1974 [1]. Glyphosate has been classified among the probable carcinogens by the International Agency for Cancer Research (IARC) of the World Health Organization [2]. Moreover, herbicide resistance is becoming a significant problem in weed management [3,4,5]. Nowadays, weeds have developed resistance to 21 of the 31 known herbicide sites of action and to 165 different herbicides [6].
Since the use of synthetic chemical herbicides is not allowed in organic agroecosystems, the scientific community is increasingly motivated to find substances that can have the same effect on weeds without compromising human and environmental health. Numerous natural substances have shown herbicidal effects, such as essential oils [7,8,9] and acetic acid [10]. Fourteen fungi and one bacterium have been registered as bioherbicides in Canada, China, Japan, The Netherlands, South Africa, and the United States [11].
Mulching is a widely used practice, especially in organic agriculture. It consists of covering of the soil with polyethylene plastic sheets or natural materials such as straw, which block the growth of weeds, although the efficacy is restricted to annual species [12,13]. Plastic mulching is suspected to be a significant source of microplastics in terrestrial environments due to its intensive application and improper disposal [14]. In 2018, the European Union (EU) adopted the first strategy for plastics, which is part of the EU’s, circular economy action plan [15,16], introducing restrictive measures on the use of various plastic products and supporting the development of biodegradable, bio-based, and compostable plastics.
Biodegradable polymers have emerged as potential alternatives to plastic sheets [17,18,19,20,21]; some of them are commercially available, while others remain under research [22]. After exhausting their weed control function, they can be incorporated into the soil by tillage, undergoing decomposition into carbon dioxide, methane, water, and inorganic compounds, mainly by the enzymatic action of microorganisms [23], resulting in poor management and environmental costs.
Some biodegradable mulches may be applied at low cost in liquid form by a simple spray pump and solidify after spreading. Two of these materials, quite well known, are chitosan, a low-cost biopolymer usually obtained from discarded crustacean shells of the food industry [24], and galactomannans, neutral heteropolysaccharides composed of galactose and mannose, obtained from the endosperm of seeds of some Leguminous plants, in which they have several functions, including a reserve of carbohydrates [25]. Galactomannan or chitosan applied to the soil forms a thin biodegradable biofilm. Charcoal (an organic compound produced by the incomplete combustion of organic matter) has also been tested in combination with the two biopolymers for its ability to shade the buds of weeds, hindering their growth [26].
Spray coatings based on different formulations of biodegradable compounds have been tested to assess their stability. Kirchinger and coworkers [27] reported a mulching effect of six months of a material composed by a water-based starch and an oil-based sodium alginate compound. Immirzi et al. [28], studying the performance of a galactomannan and cellulose mulching spray on lettuce crops, reported better results under a greenhouse controlled atmosphere than in open fields. Schettini et al. [29] reported a persistence in greenhouses of up to 18 months of novel mulching biodegradable polymeric materials based on hydrolyzed proteins derived from the leather industry. However, none of these studies investigated the efficacy of the mulches directly on weed emergence.
The efficacy of chitosan-derived mulching sprays in controlling the growth of weeds was tested on Viburnum lucidum Mill. [30] and on Haematococcus pluvialis [31] cultivations. Both studies resulted in efficient inhibition of weed germination and growth without phytotoxic effects on the crops. However, these experiments were carried out in containers or pots, where the mulch is subjected to less stress than on larger surfaces.
In order to explore sustainable weed management in modern agroecosystems, we focused on possible alternatives to synthetic chemical herbicides and traditional plastic mulches on the growth of weeds naturally occurring in horticultural soils. In particular, the research aims at investigating, under greenhouse conditions, (i) the mulching effect of chitosan- and galactomannan-based liquid spray coatings, with or without the addition of five essential oils and charcoal, as an environmentally friendly tool for weed control; (ii) the ability of false seeding to increase the effectiveness of spray mulching to control weed germination, an aspect that has not been investigated.

2. Materials and Methods

2.1. Mulching Treatments

The field experiments were carried out under a multi-tunnel greenhouse at CREA-Research Center for vegetable and ornamental crops in Pontecagnano (Province of Salerno, Italy; 40°38′ N, 14°53′ E, 48 m a.s.l.). The soil, naturally infested with several species of weeds, is a Calcaric Cambisol with the following properties [29]: sand, silt, and clay, 430, 390, and 180 g kg−1, respectively; soil organic carbon (SOC), 26 g kg−1; total N, 2.3 g kg−1; available P, 52 mg kg−1; pH(H2O), 7.9. The study consisted of two experiments, each replicated twofold in different seasons. Each experiment was carried out on different soil areas under the same multi-tunnel (Figure 1) after soil milling at 15 cm of depth.

2.1.1. Experiment 1

The soil surface was divided into 45 plots of one square meter each, and the soil was wetted with 30 mm of water to promote the interruption of dormancy of weed seed or other propagules (false seeding). The following day, each plot was split in two halves: one was left untreated, and the other one was treated with one of the fifteen combined associations of biopolymer + additive + essential oil, as reported in Table 1. The plots were distributed according to a randomized block design with three replicates.
In each half-plot treated, 1 L of an aqueous suspension containing one/neither of the two biopolymers (chitosan and galactomannan; Lianyungang Zhongda Seaweed Industrial Co., LTD; Lianyungang, China) alone or together with light-masking vegetable charcoal and with or without the addition of one of the five essential oils (caraway, oregano, rosemary, thyme, lemon balm; ACEF; Piacenza, Italy) at a concentration of 1% v/v was sprayed by an ordinary device for phytoiatric treatments. The chitosan was also added with glycerol, cellulose fiber, and acetic acid as chitosan solubilizing agents to 3% v/v final concentration. Each plot was irrigated by sprinkling with 10 mm of water 3 times a week from treatment application until the weeds were collected (see Section 2). This experiment was replicated in two seasons: Spring and Autumn 2016, with treatments applied on 30 March 2016 and 3 October 2016, respectively.

2.1.2. Experiment 2

The most effective and simple treatment from Experiment 1 (i.e., the biopolymer chitosan added with charcoal, glycerol, cellulose fiber, and acetic acid, with no essential oils) was further investigated for its effects on plants and soil microbial community using the same dosage per half plot, also testing the effect of increasing from one to three days the delay between the false seeding and the execution of the liquid mulching treatment to the soil. An experimental block design was used, alternating the plots with one and three days of delay and seven replicates. The experiment was repeated in two seasons: Winter and Summer 2017, with treatments applied on 2 December 2016 and 17 July 2017, respectively.

2.2. Plant Reliefs

The plant reliefs were carried out on 17 May 2016 and 1 December 2016 in Experiment 1 and on 15 March 2017 and 11 August 2017 in Experiment 2. In both the experiments, in a square of 0.2 m2 at the center of the two half plots, grown weeds were taxonomically identified, and the number of plants as well as the aboveground fresh and dry biomasses of annual and perennial species were determined.

2.3. Soil Sampling and Pre-Treatment

Surface (0–5 cm of depth) soil samples were collected from the treated half-plots and from the coupled untreated half-plots on 6 May 2016 and 21 December 2016 and on 15 March 2017 and 25 August 2017. In each half-plot, four soil cores were collected by a gouge auger and pooled to obtain a homogenous sample per plot. Soil samples were sieved (2 mm) and stored at 4 °C until the laboratory analyses.

2.4. Soil Laboratory Analyses

For soil analyses, we considered that any exogenous material introduced into the soil system might potentially alter the biomass and the activity of the microbial community, with unpredictable consequences on soil functions; for instance, chitosan may have antimicrobial effects [32,33]. For this reason, we investigated the effects of the mulching treatment with chitosan, with or without additives, on some microbiological and biochemical indicators of soil quality and health: (i) the microbial biomass, which is indicative of more or less favorable conditions for microbial growth [34]; (ii) the basal respiration, i.e., the measurement of the CO2 evolution by the microbial community in steady-state conditions, which is indicative of the intensity of the microbial metabolism involved in organic matter decomposition [35]; (iii) the FDA hydrolysis activity, attributable to several non-specific lipases, proteases, and esterases, indicative of the general heterotrophic activity of the soil microbial community [36]; and (iv) the substrate-induced respiration after D-glucosamine addition to soil samples, which may reveal the effects of the exposure to chitosan on microbial metabolism [37]. To this end, soil samples from each half plot were separately analyzed in two replicates. FDA hydrolysis activity was determined according to Gonzalez-Quiñones et al. [34]. Basal respiration was assessed by measuring the CO2 evolution from soil samples incubated as described in Iovieno et al. [38]. The CO2 evolution induced by the amendment of soil samples with D-glucose or D-glucosamine was assessed according to Degens et al. [39]. The C-CO2 evolved after glucose amendment was assumed as an indicator of microbial biomass according to the SIR method [40]. The basal and the glucose or D-glucosamine-induced respiration of soil samples were measured as CO2 concentration in the headspace of glass vials by a gas chromatograph (GC6850, Agilent Technologies, Inc.; Santa Clara, CA, USA) equipped with a thermal conductivity detector and a capillary HP PLOT Q column.

2.5. Statistical Analysis

The significance of differences between each treatment and its own untreated control was tested by one-way analysis of variance (ANOVA), followed by Tukey’s test (for α = 0.05) for mean comparisons. Before ANOVAs, data were tested for normality and homoscedasticity through Shapiro and Bartlett tests, respectively.

3. Results

3.1. Experiment 1

Plant reliefs resulted in the identification of six annual and three perennial species. Annual species were common purslane (Portulaca oleracea L.), redroot pigweed (Amaranthus retroflexus L.), fat hen (Chenopodium album L.), black nightshade (Solanum nigrum L.), stinging nettle (Urtica dioica L.), and shepherd’s purse (Capsella bursa-pastoris L.) in both seasons. Perennial plants were couch grass (Cynodon dactylon L.) and cyperus (Cyperus sp.) in both seasons, and also bindweed (Convolvulus sp.) in Autumn. The results of the Experiment 1 showed that galactomannan alone, with the addition of charcoal or with the addition of charcoal plus each of the five essential oils, had no effects on weed growth in comparison to the non-treated control (Table 2).
On the contrary, chitosan, in all combinations, resulted in a noticeable reduction in the number as well as in the fresh and dry biomass of annual plants in comparison with non-treated controls, even though differences were not always significant (Table 3). Significant differences between treated and untreated plots were reported particularly in Spring, for plant number. In that season, the percentage of reduction of annual plant number was 63% with chitosan alone, which was generally similar to or higher than that found with the addition of essential oils. The only exception was the addition of thyme essential oil, which reduced by 77% the number of annual plants in comparison to the untreated control. The addition of charcoal resulted in a significant reduction of annual plant fresh biomass in Spring and dry biomass in Autumn. In Spring, the addition of caraway appeared to increase the percentage of reduction of annual plant dry biomass from 54% for chitosan alone to 68%. In the other cases, the addition of essential oils did not show significant differences in comparison to untreated controls and did not increase the effects produced by chitosan alone or with charcoal. No detectable effect was observed in the growth of the perennial plants in Autumn. During the Spring, in the non-treated half-plots, the perennial species did not vegetate, or they did negligibly.

3.2. Experiment 2

In Experiment 2, only chitosan with charcoal treatment was used as well as the delay of one or three days from false seeding, and the treatment was tested for its ability to improve the herbicidal effect. Annual plants were the same as in Experiment 1, except for stinging nettle and shepherd’s purse, which were not found in Summer. Perennial plants were couch grass, cyperus, and bindweed in both seasons. The treatment with chitosan and charcoal applied one day after false seeding showed a reduction of the number of annual plants (Figure 2) in both seasons (Winter and Summer 2017), whereas fresh and dry biomass were significantly reduced only in Winter, by 86 and 84%, respectively.
In the plots treated three days after the false seeding, the presence of annual plants was set to zero in Summer, whereas in Winter their number was reduced by 73% and their fresh as well as dry biomass by 93% (Figure 2). No significant effect was found in perennial species, neither in Winter when the plants grew little or not at all, nor in Summer, when growth was vigorous (Figure 3).

3.3. Soil Microbial Biomass and Activity

Due to the lack of herbicidal efficacy of treatments with galactomannan, the soil microbial biomass and activity in Experiment 1 were measured only in the plots treated with chitosan, with or without additives. No significant differences were found between any treatment and the untreated control and among treatments, neither in Spring nor in Winter, for all the measured parameters (Figure 4).
In Experiment 2 (Figure 5) only the D-glucosamine-induced respiration and FDA hydrolysis activity showed a significant effect of the treatment. D-glucosamine-induced respiration was higher in the plots treated with chitosan + charcoal applied after three days of false seeding than in the corresponding untreated control in Winter only (+11%), whereas no differences were found in Summer.
FDA hydrolysis activity was lower in the plots treated with chitosan + charcoal at both one and three days of delay than in the corresponding untreated control, only in Summer.

4. Discussion

In our experimental conditions, chitosan was shown to be more efficient than galactomannan in weed control. In fact, galactomannan did not show the ability to reduce the germination and the growth of weeds, neither alone nor with the addition of charcoal or of charcoal plus essential oils. By contrast, the number of annual plants, such as common purslane (Portulaca oleracea L.), redroot pigweed (Amaranthus retroflexus L.), fat hen (Chenopodium album L.), black nightshade (Solanum nigrum L.), stinging nettle (Urtica dioica L.), and shepherd’s purse (Capsella bursa-pastoris L.), appeared noticeably reduced by chitosan application. The inhibiting effects of chitosan on annual grasses agrees with the findings of Giaccone [30], who tested this mulch on the weeds prickly sowthistle (Sonchus asper (L.) Hill subsp. asper), and broad-leaved willowherb (Epilobium montanum L.) seeded in containers.
The ability of chitosan + charcoal treatment to significantly reduce the fresh and dry annual plant biomass in Spring and Autumn, respectively, suggests that the efficacy of chitosan may be improved by the addition of charcoal, likely due to blocking of light penetration through the mulching film [41]. Braunak et al. [42] also reported that the addition of charcoal to a sprayable biodegradable polymer membrane enhanced its inhibition of seedling emergence. Essential oils generally did not enhance the weed inhibition of both galactomannan and chitosan. An herbicidal effect of up to 40% for pine essential oil was reported by Young [43]. In our study, we cannot exclude that the effect of essential oils was masked by their entrapment in the biopolymer [44]. In consideration of the high commercial cost and the dubious herbicidal effectiveness found, essential oils were excluded in the subsequent experimentation.
Spray mulching coatings applied after three days of false seeding had significant effects on annual weed reduction compared to the untreated control, where seed germination of the weeds identified as redroot pigweed, shepherd’s purse, fat hen, stinging nettle, common purslane, and black nightshade in Winter and common purslane, redroot pigweed, fat hen, and black nightshade in Summer regularly occurred. Usually, the false seeding allows seeds to germinate and be destroyed by mechanical processing. In this work, the spray replaced the processing: the greater herbicidal efficacy of the three-day-delay treatment is explained by the greater number of germinated seedlings on which the chitosan mixture was able to act.
No significant effect of treatments was found on the growth of perennial species, represented mainly by bindweed, couch grass, and cyperus, neither in Winter when the plants grew little or not at all, nor in Summer, when growth was vigorous. Their mode of propagation, not by seed as annual plants but by cuttings and rhizomes, allowed them to vegetate regularly, explaining the lack of herbicidal efficacy of chitosan. The low effect on perennial species is in line with what was found with mulching with plastic films [45,46]. Other studies confirmed the cyperus capacity for sprouting independently of mulching [12,13]. However, rhizome reduction, especially on Paspalum dilatatum (not present in our test) was found using spray mulches [47].
Several additional management techniques that decrease field bindweed, including mowing, grazing, crop diversification, solarization, shading, flaming, and crop competition, have been proposed [48]. The prolonged exposure of films to weathering agents (solar radiation, high air temperature, relative humidity, etc.) and the employment of chemical substances determine progressive degradation and photo-oxidation processes with a variation of physical and mechanical properties of the films [49].
In order to simulate the natural weathering endured by chitosan-cellulose-based coatings during their permanence on the soil, the biocomposite was exposed to an accelerated photo-degradation process of several hours to UV rays, and only after 300 h of exposure was there a gradual degradation of both chitosan and fiber [50]. Beyond the duration of biodegradable mulch and the efficacy on weed growth inhibition, an effect on fruit production and the quality of muskmelon was reported [51].
Though chitosan has been recently used in agriculture to control plant diseases, exhibiting toxic effects and inhibiting fungal growth [52], soil microbial biomass and activity was not negatively affected by treatments with chitosan, with or without additives; similarly, chitosan added with charcoal did not affect soil quality, with a few exceptions. In fact, FDA hydrolysis activity in Summer decreased in the plots treated one and three days after false seeding in comparison to untreated ones. However, this was the only parameter showing a noticeable reduction under chitosan mulching in comparison to the untreated control, and the variation of a single parameter (only in one sampling of the second experiment) is not sufficiently indicative to assess changes in soil quality [53]. D-glucosamine-induced respiration slightly increased only in the plots treated three days after false seeding in Winter. Though this increase was statistically significant, we cannot exclude that it could be due to that specific site of the experimental field and to the particular moment, as our data do not show other cases of an increase in this parameter attributable to chitosan. O’Dowd and Hopkins [37] reported that microbial respiration induced by amino acid addition to soil was increased by previous exposures to the same compound: in a laboratory experiment, they found that repeated amendment of a forest soil with single amino acids determined an increase in substrate-induced respiration rate up to 200% after the second dose, applied 18 days after the first.
The general lack of differences among treatments and the corresponding control suggests that (i) the treatments did not alter the microbial biomass; (ii) there was not a marked preferential growth of microbial populations better able to metabolize the monomer of chitin as a source of carbon and energy; (iii) there was no change in the physiological status of the autochthonous microflora; (iv) there does not appear to be an increase in the expression of genes encoding specific membrane transporters or enzymes involved in the metabolic pathway leading to the mineralization of chitosan and D-glucosamine. The overall results suggest that chitosan + charcoal, with or without essential oils, did not produce an evident alteration of the biomass and the functioning of the microbial community, at least for the measured functions. However, since these parameters are widely accepted as indicators of soil health [54,55] it is reasonable to state that there is no evidence that the treatments have deleterious effects on the soil biological system. This result is ecologically relevant, since chitosan is known to have an antimicrobial effect [32,33,52]. Despite the encouraging results of this study, it should be underlined that they do not allow highlighting potential synergic or antagonistic interactions among the biodegradable polymer, essential oils, and charcoal on weed growth and soil quality. Likewise, information about the potential influence of environmental factors such as different temperatures and soil moisture on the effectiveness of biodegradable spray mulch application is missing. This lack of knowledge limits the applicability of the studied treatments on a large spatial scale and points to the need for further studies.

5. Conclusions

The current study demonstrates that it is possible to control weeds by natural mulching that remains stable on the soil for the whole duration of the crop cycle. In the present research, the chitosan-based mixture resulted in an effective treatment against annual weeds. The herbicide effectiveness was improved by a three-day delay of the treatment after the false seeding. In the organic culture of transplanted vegetables, the proposed treatment could be preferable to biodegradable films, which show variable results depending on the weather trend. The application in the cultivation of sown vegetables, for which it is not possible to use mulching films, must be verified. The studied treatments seem to be sustainable and environmentally friendly, since no evidence of a negative impact on soil microbial biomass and activity was found.

Author Contributions

Conceptualization, P.I. and A.V.; methodology, P.I. and A.V.; validation, P.I. and A.V.; formal analysis, P.I. and A.V.; investigation, M.C., C.D.C., P.I., B.I., D.B., M.S., M.Z. and A.V.; resources, P.I., B.I., D.B., M.Z. and A.V.; data curation, M.C., P.I. and A.V.; writing—original draft preparation, M.C., P.I. and A.V.; writing—review and editing, M.C., C.D.C., P.I., B.I., D.B., M.S., M.Z. and A.V.; visualization, M.C., P.I. and A.V.; supervision, A.V.; project administration, A.V.; funding acquisition, A.V. All authors have read and agreed to the published version of the manuscript.

Funding

This research was supported by MIUR, Research Projects: ‘Research advanced materials for Agro-food, MAReA’; PON03_00106_1.

Data Availability Statement

Data are contained within the article.

Acknowledgments

The authors would like to remember Mario Malinconico, a Scientist at CNR-IPCB (Pozzuoli, NA, Italy) who passed away during the Summer of 2021, as an inventor of this type of approach to mulching and the environment. Moreover, the authors are grateful to Pasquale Mormile, a researcher at CNR-ISASI (Pozzuoli, NA, Italy), for providing galactomannan, and to Riccardo Scotti, a researcher at CREA-Research Centre for Vegetable and Ornamental Crops (Pontecagnano, SA, Italy), who kindly revised the English language of the manuscript.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Van Bruggen, A.H.C.; He, M.M.; Shin, K.; Mai, V.; Jeong, K.C.; Finckh, M.R.; Morris, J.G. Environmental and health effects of the herbicide glyphosate. Sci. Total Environ. 2018, 616–617, 255–268. [Google Scholar] [CrossRef] [PubMed]
  2. Portier, C.J.; Armstrong, B.K.; Baguley, B.C.; Baur, X.; Belyaev, I.; Bellé, R.; Belpoggi, F.; Biggeri, A.; Bosland, M.C.; Bruzzi, P.; et al. Differences in the carcinogenic evaluation of glyphosate between the International Agency for Research on Cancer (IARC) and the European Food Safety Authority (EFSA). J. Epidemiol. Community Health 2016, 70, 741–745. [Google Scholar] [CrossRef]
  3. Dentzman, K.; Burke, I.C. Herbicide resistance, tillage, and community management in the Pacific Northwest. Sustainability 2021, 13, 1937. [Google Scholar] [CrossRef]
  4. Duke, S.O. Why have no new herbicide modes of action appeared in recent years? Pest Manag. Sci. 2012, 68, 505–512. [Google Scholar] [CrossRef] [PubMed]
  5. Kraehmer, H. Innovation: Changing trends in herbicide discovery. Outlooks Pest Man. 2012, 23, 115–118. [Google Scholar] [CrossRef]
  6. Heap, I. The International Herbicide-Resistant Weed Database. Available online: www.weedscience.org (accessed on 5 June 2024).
  7. Blázquez, M.A.; Carbó, E. Control of Portulaca oleracea by boldo and lemon essential oils in different soils. Ind. Crop Prod. 2015, 76, 515–521. [Google Scholar] [CrossRef]
  8. Nikolova, M.; Traykova, B.; Yankova-Tsvetkova, E.; Stefanova, T.; Dzhurmanski, A.; Aneva, I.; Berkov, S. Herbicide potential of selected essential oils from plants of Lamiaceae and Asteraceae families. Acta Agrobot. 2021, 74, 7411. [Google Scholar] [CrossRef]
  9. Hazrati, H.; Saharkhiz, M.J.; Niakousari, M.; Moein, M. Natural herbicide activity of Satureja hortensis L. essential oil nanoemulsion on the seed germination and morphophysiological features of two important weed species. Ecotoxicol. Environ. Saf. 2017, 142, 423–430. [Google Scholar] [CrossRef]
  10. Yang, N.; Sun, Z.X.; Feng, L.S.; Zheng, M.Z.; Dao-Cai, C.; Meng, W.Z.; Hou, Z.Y.; Bai, W.; Li, K.Y. Plastic film mulching for water-efficient agricultural applications and degradable films materials development research. Mat. Manuf. Proc. 2014, 30, 143–154. [Google Scholar] [CrossRef]
  11. Sindhu, S.S.; Khandelwal, A.; Phour, M.; Sehrawat, A. Bioherbicidal potential of rhizosphere microorganisms for ecofriendly weed management. In Role of Rhizospheric Microbes in Soil; Meena, V., Ed.; Springer: Singapore, 2018; Volume 1. [Google Scholar]
  12. Mas, M.T.; Pardo, G.; Pueyo, J.; Verdú, A.; Cirujeda, A. Can hydromulch reduce the emergence of perennial weeds? Agronomy 2021, 11, 393. [Google Scholar] [CrossRef]
  13. Mzabri, I.; Rimani, M.; Charif, K.; Kouddanne, N.; Bericchi, A. Study of the effect of mulching materials on weed control in Saffron cultivation in eastern Morocco. Sci. World J. 2021, 9727004. [Google Scholar] [CrossRef] [PubMed]
  14. Huang, Y.; Liu, Q.; Jia, W.; Yan, C.; Wang, J. Agricultural plastic mulching as a source of microplastics in the terrestrial environment. Environ. Pollut. 2020, 260, 114096. [Google Scholar] [CrossRef] [PubMed]
  15. European Commission Proposal for a Directive of the European Parliament and of the Council on the Reduction of the Impact of Certain Plastic Products on the Environment. Brussels, 28 May 2018, COM 28 Final. Available online: https://eur-lex.europa.eu/legal-content/en/ALL/?uri=CELEX%3A52018PC0340 (accessed on 11 July 2024).
  16. UNEP. Single-Use Plastics: A Roadmap for Sustainability United Nations Environment Programme; UNEP: Nairobi, Kenya, 2018; Available online: www.unep.org/resources/report/single-use-plastics-roadmap-sustainability (accessed on 11 July 2024).
  17. Sartore, L.; Schettini, E.; De Palma, L.; Brunetti, G.; Cocozza, C.; Vox, G. Effect of hydrolyzed protein-based mulching coatings on the soil properties and productivity in a tunnel greenhouse crop system. Sci. Total Environ. 2018, 645, 1221–1229. [Google Scholar] [CrossRef] [PubMed]
  18. Vox, G.; Santagata, G.; Malinconico, M.; Immirzi, B.; Mugnozza, G.S. Biodegradable films and spray coatings as eco-friendly alternative to petro-chemical derived mulching films. J. Agric. Eng. 2013, XLIV, e44. [Google Scholar] [CrossRef]
  19. Adhikari, R.; Bristow, K.L.; Casey, P.S.; Freischmidt, G.; Hornbuckle, J.W.; Adhikari, B. Preformed and sprayable polymeric mulch film to improve agricultural water use efficiency. Agric. Water Manag. 2016, 169, 1–13. [Google Scholar] [CrossRef]
  20. Malinconico, M.; Santagata, G.; Schettini, E. Sprayable polysaccharide-based fiber reinforced emulsions for environmentally sound plasticulture. Macromol. Symp. 2006, 245–246, 578–583. [Google Scholar] [CrossRef]
  21. Mormile, P.; Petti, L.; Rippa, M.; Immirzi, B.; Malinconico, M.; Santagata, G. Monitoring of the degradation dynamics of agricultural films by IR thermography. Polym. Degrad. Stab. 2007, 92, 777–784. [Google Scholar] [CrossRef]
  22. Kasirajan, S.; Ngouajio, M. Polyethylene and biodegradable mulches for agricultural applications: A review. Agron. Sustain. Dev. 2012, 32, 501–529. [Google Scholar] [CrossRef]
  23. Song, J.H.; Murphy, R.J.; Narayan, R.; Davies, G.B.H. Biodegradable and compostable alternatives to conventional plastics. Philos. Trans. R. Soc. B Biol. Sci. 2009, 364, 2127–2139. [Google Scholar] [CrossRef]
  24. Kumar, M.N.R. A review of chitin and chitosan applications. React. Funct. Polym. 2000, 46, 1–27. [Google Scholar] [CrossRef]
  25. Reid, J.S.G.; Edwards, M.E. Galactomannans and other cell wall storage polysaccharides in seeds. In Food Polysaccharides and Their Application; Stephen, A.M., Ed.; Marcel Dekker Inc.: New York, NY, USA, 1995; pp. 155–186. [Google Scholar]
  26. Anifantis, A.; Canzio, G.; Cristiano, G.; De Lucia, B.; Russo, G.; Vecchietti, L.; Immirzi, B.; Malinconico, M.; Santagata, G. Influence of the use of drip irrigation systems and different mulching materials on ornamental sunflowers in greenhouse cultivation. Acta Hortic. 2011, 952, 385–392. [Google Scholar] [CrossRef]
  27. Kirchinger, M.; Holzknecht, E.; Redl, M.; Steinkellner, S.; Emberger, P.; Remmele, E. A spray-on environmentally friendly degradable mulch material and its high efficiency in controlling above-ground biomass of weeds in greenhouse experiments. J. Plant Dis. Prot. 2024, 131, 1009–1020. [Google Scholar] [CrossRef]
  28. Immirzi, B.; Malinconico, M.; Santagata, G. Characterization of galactomannans and cellulose fibres based composites for new mulching spray technology. Acta Hortic. 2008, 801, 195–202. [Google Scholar] [CrossRef]
  29. Schettini, E.; Sartore, L.; Barbaglio, M.; Vox, G. Hydrolyzed protein based materials for biodegradable spray mulching coatings. Acta Hortic. 2012, 952, 359–366. [Google Scholar] [CrossRef]
  30. Giaccone, M.; Cirillo, C.; Scognamiglio, P.; Teobaldelli, M.; Mataffo, A.; Stinca, A.; Pannico, A.; Immirzi, B.; Santagata, G.; Malinconico, M.; et al. Biodegradable mulching spray for weed control in the cultivation of containerized ornamental shrubs. Biol. Technol. Agric. 2018, 5, 21. [Google Scholar] [CrossRef]
  31. Lee, J.B.; Park, Y.H.; Jeon, M.S.; Kim, S.; E Choi, Y. Polyethylenimine linked with chitosan improves astaxanthin production in Haematococcus pluvialis. Appl. Microbiol. Biot. 2023, 107, 569–580. [Google Scholar] [CrossRef] [PubMed]
  32. Rabea, E.I.; Badawy, M.E.-T.; Stevens, C.V.; Smagghe, G.; Steurbaut, W. Chitosan as antimicrobial agent: Applications and mode of action. Biomacromolecules 2003, 4, 1457–1465. [Google Scholar] [CrossRef] [PubMed]
  33. El Hadrami, A.; Adam, L.R.; El Hadrami, I.; Daayf, F. Chitosan in plant protection. Marine Drugs 2010, 8, 968–987. [Google Scholar] [CrossRef] [PubMed]
  34. Gonzalez-Quiñones, V.; Stockdale, E.A.; Banning, N.C.; Hoyle, F.C.; Sawada, Y.; Wherrett, A.D.; Jones, D.L.; Murphy, D.V. Soil microbial biomass. Interpretation and consideration for soil monitoring. Soil Res. 2011, 49, 287–304. [Google Scholar] [CrossRef]
  35. Wang, W.J.; Dalal, R.C.; Moody, P.W.; Smith, C.J. Relationship of soil respiration to microbial biomass, substrate availability and clay content. Soil Biol. Biochem. 2003, 35, 273–284. [Google Scholar] [CrossRef]
  36. Schnürer, J.; Rosswall, T. Fluorescein diacetate hydrolysis as a measure of total microbial activity in soil and litter. Appl. Environ. Microbiol. 1982, 43, 1256–1261. [Google Scholar] [CrossRef] [PubMed]
  37. O’Dowd, R.W.; Hopkins, D.W. Mineralization of carbon from D- and L-amino acids and D-glucose in two contrasting soils. Soil Biol. Biochem. 1998, 30, 2009–2016. [Google Scholar] [CrossRef]
  38. Iovieno, P.; Morra, L.; Leone, A.; Pagano, L.; Alfani, A. Effect of organic and mineral fertilizers on soil respiration and enzyme activities of two Mediterranean horticultural soils. Biol. Fertil. Soils 2009, 45, 555–561. [Google Scholar] [CrossRef]
  39. Degens, B.P.; Schipper, L.A.; Sparling, G.P.; Vojvodic-Vukovic, M. Decreases in organic C reserves in soils can reduce the catabolic diversity of soil microbial communities. Soil Biol. Biochem. 2000, 32, 189–196. [Google Scholar] [CrossRef]
  40. Anderson, J.P.E.; Domsch, K.H. A physiological method for the quantitative measurement of microbial biomass in soils. Soil Biol. Biochem. 1978, 10, 215–221. [Google Scholar] [CrossRef]
  41. Indurthi, S.; Ashoka, P.; Saikanth, D.R.K.; Das, H.; Kumar, V.; Pancholi, R. Application and impacts of mulch installation techniques on Indian horticulture: An in-depth review. Int. J. Plant Soil Sci. 2023, 35, 2135–2147. [Google Scholar] [CrossRef]
  42. Braunak, M.V.; Zaja, A.; Tam, K.; Filipovic, L.; Filipovic, V.; Wang, Y.; Bristow, K.L. A sprayable biodegradable polymer membrane (SBPM) technology: Effect of band width and application rate on water conservation and seedling emergence. Agric. Water Manag. 2020, 230, 105900. [Google Scholar] [CrossRef]
  43. Young, S.L. Natural product herbicides for control of annual vegetation along roadsides. Weed Technol. 2004, 18, 580–587. [Google Scholar] [CrossRef]
  44. Assadpour, E.; Can Karaça, A.; Fasamanesh, M.; Mahdavi, S.A.; Shariat-Alavi, M.; Feng, J.; Kharazmi, M.S.; Rehman, A.; Jafari, S.M. Application of essential oils as natural biopesticides; recent advances. Crit. Rev. Food Sci. Nutr. 2024, 64, 6477–6497. [Google Scholar] [CrossRef]
  45. Abbate, C.; Scavo, A.; Pesce, G.R.; Fontanazza, S.; Restuccia, A.; Mauromicale, G. Soil bioplastic mulches for agroecosystem sustainability: A comprehensive review. Agriculture 2023, 13, 197. [Google Scholar] [CrossRef]
  46. Radics, L.; Bognar, E.S. Comparison of different mulching method for weed control in organic green bean and tomato. Acta Hortic. 2004, 638, 189–196. [Google Scholar] [CrossRef]
  47. Mas, M.T.; Verdú, A.M.C.; Pardo, G.; Pueyo, J.; Claramunt, J.; Cirujeda, A. Shoot and biomass reduction of perennial weeds using hydromulches and physical changes in the mulches. J. Plant Dis. Prot. 2024, 131, 433–443. [Google Scholar] [CrossRef]
  48. Orloff, N.; Mangold, J.; Miller, Z.; Menalled, F. A meta-analysis of field bindweed (Convolvulus arvesis L.) and Canada thistle (Cirsium arvense L.) management in organic agricultural systems. Agric. Ecosyst. Environ. 2018, 254, 264–272. [Google Scholar] [CrossRef]
  49. Feuilloley, P.; Cesar, G.; Benguigui, L.; Grohens, Y.; Pillin, I.; Bewa, H.; Lefaux, S.; Jamal, M. Degradation of polyethylene designed for agricultural purposes. J. Polym. Environ. 2005, 13, 349–355. [Google Scholar] [CrossRef]
  50. Santagata, G.; Schettini, E.; Vox, G.; Immirzi, B.; Mugnozza, S.; Malinconico, M. Biodegradable spray mulching and nursery pots: New frontiers for research. In Soil Degradable Bioplastics for a Sustainable Modern Agriculture, Green Chemistry and Sustainable Technology; Malinconico, M., Ed.; Springer: Berlin/Heidelberg, Germany, 2017; pp. 121–124. [Google Scholar]
  51. Cozzolino, E.; Di Mola, I.; Ottaiano, L.; Bilotto, M.; Petriccione, M.; Ferrara, E.; Mori, M.; Morra, L. Assessing yield and quality of melon (Cucumis melo L.) improved by biodegradable mulching film. Plants 2023, 12, 219. [Google Scholar] [CrossRef] [PubMed]
  52. Mackiewicz-Walec, E.; Olszewska, M. Biostimulants in the production of forage grasses and turfgrasses. Agriculture 2023, 13, 1796. [Google Scholar] [CrossRef]
  53. Schloter, M.; Dilly, O.; Munch, J.C. Indicators for evaluating soil quality. Agric. Ecosyst. Environ. 2003, 98, 255–262. [Google Scholar] [CrossRef]
  54. Alkorta, I.; Aizpurua, A.; Riga, P.; Albizu, I.; Amézaga, I.; Garbisu, C. Soil enzyme activities as biological indicators of soil health. Rev. Environ. Health 2003, 18, 65–73. [Google Scholar] [CrossRef]
  55. Cardoso, E.J.B.N.; Vasconcellos, R.L.F.; Bini, D.; Miyauchi, M.Y.; dos Santos, C.A.; Lopes Alves, P.R.; de Paula, A.M.; Nakatani, A.S.; de Moraes Pereira, J.; Nogueira, M.A. Soil health: Looking for suitable indicators. What should be considered to assess the effects of use and management on soil health? Sci. Agric. 2013, 70, 274–289. [Google Scholar] [CrossRef]
Sustainability 16 05973 g001
Figure 1. A panoramic view of the experimental field set up under a multi-tunnel greenhouse at CREA-Research Center for vegetable and ornamental crops in southern Italy.
Figure 1. A panoramic view of the experimental field set up under a multi-tunnel greenhouse at CREA-Research Center for vegetable and ornamental crops in southern Italy.
Sustainability 16 05973 g001
Sustainability 16 05973 g002
Figure 2. Number, fresh biomass, and dry biomass of annual plants in Winter (A) and Summer (B) 2017 in the plot treated with chitosan + charcoal 1 or 3 days after false seeding (Chit + char:1 and Chit + char:3) and in the corresponding non-treated control (NT:1 and NT:3). Different letters indicate significant differences (for α = 0.05).
Figure 2. Number, fresh biomass, and dry biomass of annual plants in Winter (A) and Summer (B) 2017 in the plot treated with chitosan + charcoal 1 or 3 days after false seeding (Chit + char:1 and Chit + char:3) and in the corresponding non-treated control (NT:1 and NT:3). Different letters indicate significant differences (for α = 0.05).
Sustainability 16 05973 g002
Sustainability 16 05973 g003
Figure 3. Number, fresh biomass, and dry biomass of perennial plants in Winter (A) and Summer (B) 2017 in the plot treated with chitosan + charcoal 1 or 3 days after false seeding (Chit + char:1 and Chit + char:3) and in the corresponding non-treated control (NT:1 and NT:3). Different letters indicate significant differences (for α = 0.05).
Figure 3. Number, fresh biomass, and dry biomass of perennial plants in Winter (A) and Summer (B) 2017 in the plot treated with chitosan + charcoal 1 or 3 days after false seeding (Chit + char:1 and Chit + char:3) and in the corresponding non-treated control (NT:1 and NT:3). Different letters indicate significant differences (for α = 0.05).
Sustainability 16 05973 g003
Sustainability 16 05973 g004
Figure 4. Microbial biomass, basal respiration, FDA hydrolysis activity, and glucosamine-induced respiration (SIR D-glucosamine) measured in Spring (A) and in Autumn (B) 2016 in the soils treated with chitosan (Chit) + charcoal (char) + essential oils, chitosan + charcoal, chitosan alone, and non-treated control (NT). Thym = thyme; rose = rosemary; oreg = oregano; lemo = lemon balm; cara = caraway. Different letters indicate significant differences (for α = 0.05).
Figure 4. Microbial biomass, basal respiration, FDA hydrolysis activity, and glucosamine-induced respiration (SIR D-glucosamine) measured in Spring (A) and in Autumn (B) 2016 in the soils treated with chitosan (Chit) + charcoal (char) + essential oils, chitosan + charcoal, chitosan alone, and non-treated control (NT). Thym = thyme; rose = rosemary; oreg = oregano; lemo = lemon balm; cara = caraway. Different letters indicate significant differences (for α = 0.05).
Sustainability 16 05973 g004
Sustainability 16 05973 g005
Figure 5. Microbial biomass, basal respiration, FDA hydrolysis activity, and glucosamine-induced respiration (SIR D-glucosamine) measured in Winter (A) and Summer (B) 2017 in the soils treated with chitosan + charcoal 1 or 3 days after false seeding (Chit + char:1 and Chit + char:3) and in the corresponding non-treated control (NT:1 and NT:3). Different letters indicate significant differences (for α = 0.05).
Figure 5. Microbial biomass, basal respiration, FDA hydrolysis activity, and glucosamine-induced respiration (SIR D-glucosamine) measured in Winter (A) and Summer (B) 2017 in the soils treated with chitosan + charcoal 1 or 3 days after false seeding (Chit + char:1 and Chit + char:3) and in the corresponding non-treated control (NT:1 and NT:3). Different letters indicate significant differences (for α = 0.05).
Sustainability 16 05973 g005
Table 1. Treatments performed in Experiment 1 carried out in a multi-tunnel greenhouse at CREA-Research Center for vegetable and ornamental crops in southern Italy, with the indication of the combined addition of biopolymer, additive, and essential oil.
Table 1. Treatments performed in Experiment 1 carried out in a multi-tunnel greenhouse at CREA-Research Center for vegetable and ornamental crops in southern Italy, with the indication of the combined addition of biopolymer, additive, and essential oil.
BiopolymerAdditiveEssential Oil
chitosancharcoalcaraway
chitosancharcoallemon balm
chitosancharcoalnone
chitosancharcoaloregano
chitosancharcoalrosemary
chitosancharcoalthyme
galactomannancharcoalcaraway
galactomannancharcoallemon balm
galactomannancharcoalnone
galactomannancharcoaloregano
galactomannancharcoalrosemary
galactomannancharcoalthyme
chitosannonenone
galactomannannonenone
nonenonenone
Table 2. Effect of treatments (T) with galactomannan (Gal), charcoal (char), and essential oils (e.o.) from thyme, rosemary, lemon balm, oregano, and caraway on growth of annual and perennial weeds in comparison with the corresponding non-treated control (NT). Coefficients of variation are reported in parentheses. Different letters indicate significant differences (for α = 0.05).
Table 2. Effect of treatments (T) with galactomannan (Gal), charcoal (char), and essential oils (e.o.) from thyme, rosemary, lemon balm, oregano, and caraway on growth of annual and perennial weeds in comparison with the corresponding non-treated control (NT). Coefficients of variation are reported in parentheses. Different letters indicate significant differences (for α = 0.05).
NumberFresh Biomass (g m−2)Dry Biomass (g m−2)
SpringAutumnSpringAutumnSpringAutumn
TNTTNTTNTTNTTNTTNT
Annual plantsGal + char + thyme e.o.85.0 a123 a101 a108 a1125 a1258 a259 a335 a113 a142 a42.0 a59.0 a
(0.44)(0.51)(0.08)(0.21)(1.03)(0.66)(0.07)(0.48)(0.94)(0.38)(0.13)(0.53)
Gal + char + rosemary e.o.123 a128 a123 a123 a2284 a1897 a332 a280 a194 a203 a66.0 a49.0 a
(0.30)(0.21)(0.17)(0.30)(0.38)(0.32)(0.40)(0.38)(0.31)(0.38)(0.40)(0.31)
Gal + char + lemon balm e.o.145 a120 a118 a76.0 a2012 a1373 a327 a257 a200 a140 a41.0 a40.0 a
(0.12)(0.18)(0.42)(0.36)(0.26)(0.27)(0.48)(0.62)(0.29)(0.29)(0.66)(0.71)
Gal + char + oregano e.o.80.0 a75.0 a196 a111 a1066 a1009 a446 a371 a127 a124 a73.0 a59.0 a
(0.60)(0.61)(0.72)(0.34)(0.51)(0.45)(0.30)(0.38)(0.46)(0.18)(0.12)(0.40)
Gal + char + caraway e.o.100 a151 a100 a123 a1875 a1809 a344 a343 a202 a221 a50.0 a64.0 a
(0.18)(0.20)(0.35)(0.06)(0.44)(0.36)(0.65)(0.13)(0.48)(0.38)(0.30)(0.25)
Gal + char128 a138 a120 a176 a1716 a1486 a362 a508 a169 a155 a46.0 a73.0 a
(0.09)(0.42)(0.76)(0.76)(0.40)(0.67)(0.94)(0.84)(0.55)(0.47)(0.97)(0.81)
Gal116 a158 a258 a125 a2246 a1759 a537 a469 a232 a205 a87.0 a78.0 a
Perennial plants (0.28)(0.13)(0.90)(0.20)(0.17)(0.28)(0.46)(0.27)(0.22)(0.38)(0.45)(0.44)
Gal + char + thyme e.o.0.00 a0.00 a105 a83.0 a0.00 a0.00 a160 a185 a0.00 a0.00 a43.0 a47.0 a
(0.00)(0.00)(0.52)(0.03)(0.00)(0.00)(0.67)(0.33)(0.00)(0.00)(0.56)(0.33)
Gal + char + rosemary e.o.0.00 a0.00 a131 a83.0 a0.00 a0.00 a156 a143 a0.00 a0.00 a43.0 a37.0 a
(0.00)(0.00)(0.76)(0.40)(0.00)(0.00)(0.75)(0.38)(0.00)(0.00)(0.94)(0.43)
Gal + char + lemon balm e.o.0.00 a0.00 a78.0 a101 a0.00 a0.00 a154 a233 a0.00 a0.00 a33.0 a44.0 a
(0.00)(0.00)(0.48)(0.16)(0.00)(0.00)(0.52)(0.33)(0.00)(0.00)(0.54)(0.19)
Gal + char + oregano e.o.0.00 a0.00 a88.0 a93.0 a0.00 a0.00 a149 a227 a0.00 a0.00 a37.0 a52.0 a
(0.00)(0.00)(0.39)(0.08)(0.00)(0.00)(0.46)(0.19)(0.00)(0.00)(0.15)(0.94)
Gal + char + caraway e.o.0.00 a0.00 a120 a75.0 a0.00 a0.00 a273 a160 a0.00 a0.00 a63.0 a43.0 a
(0.00)(0.00)(0.15)(0.35)(0.00)(0.00)(0.14)(0.82)(0.00)(0.00)(0.15)(0.94)
Gal + char0.00 a0.00 a75.0 a60.0 a0.00 a0.00 a164 a122 a0.00 a0.00 a33.0 a30.0 a
(0.00)(0.00)(0.29)(0.30)(0.00)(0.00)(0.33)(0.28)(0.00)(0.00)(0.32)(0.34)
Gal0.00 a0.00 a85.0 a66.0 a0.00 a0.00 a151 a305 a0.00 a0.00 a37.0 a42.0 a
(0.00)(0.00)(0.52)(0.24)(0.00)(0.00)(0.21)(0.34)(0.00)(0.00)(0.31)(0.02)
Table 3. Effect of treatments (T) with chitosan (Chit), charcoal (char), and essential oils (e.o.) from thyme, rosemary, lemon balm, oregano, and caraway on growth of annual and perennial weeds in comparison with the corresponding non-treated control (NT). Coefficients of variation are reported in parentheses. Different letters indicate significant differences (for α = 0.05); * = p < 0.05, ** = p < 0.01.
Table 3. Effect of treatments (T) with chitosan (Chit), charcoal (char), and essential oils (e.o.) from thyme, rosemary, lemon balm, oregano, and caraway on growth of annual and perennial weeds in comparison with the corresponding non-treated control (NT). Coefficients of variation are reported in parentheses. Different letters indicate significant differences (for α = 0.05); * = p < 0.05, ** = p < 0.01.
NumberFresh Biomass (g m−2)Dry Biomass (g m−2)
SpringAutumnSpringAutumnSpringAutumn
TNTTNTTNTTNTTNTTNT
Annual plantsChit + char + thyme e.o.48.0 a138 a41.0 a186 a294 a1594 a89.0 a376 a28.0 a182 a8.00 a43.0 a
(0.75)(0.42)(1.09)(0.75)(0.94)(0.81)(1.51)(0.85)(1.07)(0.69)(1.55)(0.61)
Chit + char + rosemary e.o.53.0 b *160 a50.0 a126 a575 a1286 a81.0 a267 a70.0 a140 a15.0 a41.0 a
(0.05)(0.19)(0.44)(0.61)(0.53)(0.59)(0.77)(0.58)(0.43)(0.51)(0.88)(0.44)
Chit + char + lemon balm e.o.38.0 b *168 a61.0 a120 a754 a2191 a77.0 a295 a93.0 a204 a10.0 a44.0 a
(0.15)(0.41)(0.05)(0.54)(0.79)(0.68)(0.57)(0.51)(0.57)(0.51)(0.75)(0.58)
Chit + char + oregano e.o.70.0 b *136 a85.0 a128 a985 a1555 a163 a440 a86.0 b *172 a11.0 b *78.0 a
(0.26)(0.13)(0.39)(0.21)(0.53)(0.12)(1.20)(0.53)(0.54)(0.13)(0.65)(0.18)
Chit + char + caraway e.o.76.0 b **153 a36.0 a115 a409 a1493 a45.0 a276 a68.0 b *214 a5.00 a44.0 a
(0.16)(0.16)(0.31)(0.69)(0.87)(0.27)(0.50)(0.93)(0.64)(0.32)(0.23)(0.81)
Chit + char56.0 a173 a55.0 a103 a434 b *1826 a55.0 a210 a69.0 a219 a6.00 b *46.07 a
(0.33)(0.42)(0.24)(0.47)(1.07)(0.29)(0.29)(0.56)(0.73)(0.42)(0.57)(0.58)
Chit55.0 b **148 a170 a210 a554 a1590 a409 a720 a71.0 b *155 a45.0 a89.0 a
Perennial plants (0.16)(0.19)(1.02)(0.95)(0.30)(0.41)(1.00)(0.43)(0.40)(0.28)(0.68)(0.39)
Chit + char + thyme e.o.10.0 a0.00 a95.0 a103 a28.0 a0.00 a156 a195 a4.00 a0.00 a33.0 a50.0 a
(0.86)(0.00)(0.97)(0.77)(0.86)(0.00)(0.65)(0.84)(0.86)(0.00)(0.65)(0.79)
Chit + char + rosemary e.o.0.00 a8.00 a88.0 a65.0 a0.00 a28.0 a113 a133 a0.00 a5.00 a27.0 a28.0 a
(0.00)(0.91)(0.66)(0.61)(0.00)(0.91)(0.91)(0.51)(0.00)(0.91)(0.97)(0.60)
Chit + char + lemon balm e.o.9.00 a0.00 a95.0 a58.0 a47.0 a0.00 a156 a140 a8.00 a0.00 a31.0 a27.0 a
(1.02)(0.00)(0.48)(0.52)(1.02)(0.00)(0.87)(0.64)(0.68)(0.00)(0.97)(0.78)
Chit + char + oregano e.o.0.00 a6.00 a153 a73.0 a0.00 a32.0 a238 a145 a0.00 a4.00 a78.0 a37.0 a
(0.00)(1.07)(0.41)(0.38)(0.00)(1.07)(0.39)(0.42)(0.00)(0.91)(0.53)(0.66)
Chit + char + caraway e.o.9.00 a16.0 a145 a115 a26.0 a85.0 a199 a241 a5.00 a12.0 a45.0 a55.0 a
(0.85)(1.08)(0.82)(0.61)(0.85)(1.08)(0.76)(0.53)(0.85)(1.08)(0.88)(0.56)
Chit + char7.00 a0.00 a125 a70.0 a42.0 a0.00 a162 a155 a7.00 a0.00 a35.0 a38.0 a
(1.06)(0.00)(0.59)(0.14)(1.06)(0.00)(0.88)(0.57)(1.06)(0.00)(0.82)(0.62)
Chit15.0 a0.00 a88.0 a45.0 a29.0 a0.00 a116 a120 a6.00 a0.00 a28.0 a23.0 a
(0.68)(0.00)(0.33)(0.51)(0.68)(0.00)(0.20)(0.73)(0.84)(0.00)(0.45)(0.63)
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Caputo, M.; Di Cesare, C.; Iovieno, P.; Immirzi, B.; Baldantoni, D.; Stipic, M.; Zaccardelli, M.; Venezia, A. Biodegradable Spray Mulch Applications in Greenhouse Agroecosystems. Sustainability 2024, 16, 5973. https://doi.org/10.3390/su16145973

AMA Style

Caputo M, Di Cesare C, Iovieno P, Immirzi B, Baldantoni D, Stipic M, Zaccardelli M, Venezia A. Biodegradable Spray Mulch Applications in Greenhouse Agroecosystems. Sustainability. 2024; 16(14):5973. https://doi.org/10.3390/su16145973

Chicago/Turabian Style

Caputo, Michele, Carlo Di Cesare, Paola Iovieno, Barbara Immirzi, Daniela Baldantoni, Marija Stipic, Massimo Zaccardelli, and Accursio Venezia. 2024. "Biodegradable Spray Mulch Applications in Greenhouse Agroecosystems" Sustainability 16, no. 14: 5973. https://doi.org/10.3390/su16145973

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop