Italian Journal of Agronomy
ISSN / EISSN : 1125-4718 / 2039-6805
Published by: PAGEPress Publications (10.4081)
Total articles ≅ 782
Latest articles in this journal
Italian Journal of Agronomy; https://doi.org/10.4081/ija.2021.1872
Cover crops and mulches have become an alternative for soil management in vineyards due to the agronomic, environmental, and economic advantages, especially the possibility of weed control. Implicitly to this objective lies the idea of assessing the potential herbicide effect of the allelochemicals released by different cover crop and mulch species. With this objective, the present work evaluated the phytotoxic effects of 12 aqueous extracts of selected species with potential use as a cover crop or mulch: a Bromus species mixture (B. hordeaceus L. and B. rubens L.), Festuca arundinacea Schreb., Hordeum murinum L., H. vulgare L., Vulpia ciliata Dumort., Medicago rugosa Desr., M. sativa L., Trifolium subterraneum L., T. incarnatum L., Phacelia tanacetifolia Benth., Sinapis alba L., and Pinus sylvestris L.,on the germination and early growth of three troublesome weeds (Conyza bonariensis (L.) Cronquist, Aster squamatus (Spreng.) Hieron, and Bassia scoparia (L.) A. J.). The different in vitro bioassays showed that aqueous extracts of some species significantly inhibited or reduced germination and root and shoot growth of the target weed species in a dose-response manner. Germination of A. squamatus and C. bonariensis was reduced by 100-80% by the different extracts applied at 50% concentration, and completely blocked at 100% concentration, except for M rugosa extract to which both species showed less sensitivity. Root elongation of A. squamatus was absolutely inhibited under every extract and concentration, whereas C. bonariensis root growth showed only some tolerance to the crude extracts of F. arundinaceaand P. sylvestris. Bassia scoparia was relatively tolerant to the aqueous plant extracts, except for T. subterraneum crude extract, which reduced total germination by 80%; otherwise, B. scoparia showed higher general sensitivity of shoot growth than the other two weed species. The chemical profiles of phenolic compounds of the aqueous extracts were obtained and identified by HPLC-DAD, the phenolic profiles of H. murinum, V. ciliata, and M. rugosa being reported in this work for the first time. Using stepwise regression, the influence of certain phenolic compounds from the aqueous extracts on the germination and early growth of weeds was predicted. Among other significant compounds, the flavonoid naringenin identified in T. subterraneumaqueous extract at 8.09 µg·mL-1 was predicted to underlie its specific phytotoxicity on B. scoparia germination. These results support the use of cover crops and mulches in weed management and can help to select the most suitable species to adopt according to the target weed species. Highlights The phytotoxic nature of the aqueous extracts of twelve conventional and novel cover crops and mulch species was demonstrated on three troublesome weed species in vineyards. Phenolic acids and flavonoids of the twelve aqueous extracts were identified and quantified by HPLC-DAD, and, by regression analysis, some allelochemicals were postulated as responsible for the phytotoxic effects. The water-soluble phenolic profiles of three potential cover crops, namely Hordeum murinum, Vulpia ciliata, and Medicago rugosa, are reported for the first time. In vitro germination and early root growth of Conyza bonariensis and Aster squamatus were almost entirely restricted by any of the twelve plants' aqueous extracts and presumably by the joint action of their particular allelopathic compounds. Bassia scoparia germination was relatively much less sensitive to the extracts, except for Trifolium subterraneum, for which the flavonoid naringenin was predicted to underlie its specific phytotoxicity.
Italian Journal of Agronomy; https://doi.org/10.4081/ija.2021.1875
Agricultural producers and scientists have long recognized both beneficial and detrimental aspects of soil tillage. With the development and adoption of herbicide-resistant crops, particularly glyphosate-resistant crops, herbicides such as glyphosate replaced the need for tillage either before or after crop planting. Thus, tillage has become less important for weed management and has been a primary enabler for the success of the majority of conservation production systems. Currently, herbicide-resistant and troublesome weeds are continually challenging agricultural decisions throughout the world. Conservation tillage hectarage are at constant risk of being converted to higher-intensity tillage systems due to lack of weed control. The shift to higher-intensity tillage facilitates burial of weed seed through use of inversion tillage and/or use of surface tillage to facilitate preplant incorporated and preemergence herbicides for control of herbicide resistant or troublesome weeds, especially in non-irrigated production. For example, Palmer amaranth (Amaranthus palmeri) has become the dominant weed problem in United States row crop production because of evolved resistance to glyphosate. Inversion tillage was clearly demonstrated to be an effective tool in helping the management of this weed. However, there is no question that most tillage operations promote soil loss, adversely affect (lower) surface water quality, and negatively impact soil productivity. Depending on the severity of the herbicide-resistant or troublesome weed infestation, multiple strategies involving integration of cultural as well as chemical weed control will be needed to overcome the need for tillage. Utilizing high biomass conservation tillage systems, such as those used extensively in South America and introduced to the United States, can help reduce the emergence of weeds by suppressing weed germination and growth. When the winter cover crop is planted early and managed for maximum growth, a dense mat is formed on the soil surface. Because weed emergence and growth are suppressed by the physical barrier and shading provided by the residue, more residue results in increased weed control. Conservation tillage systems that minimize soil disturbance (direct seeding or minimum tillage) can further reduce weed seed germination. In addition, allelopathy plays a role in weed suppression, but quantifying allelopathic effects in applied research is rarely accomplished. Creative research programs have been developed that meet conservation compliance requirements and at the same time judiciously use tillage as an element for management of resistant or troublesome species. Similar programs are needed to help manage other herbicide resistant or troublesome weed species in other regions and cropping systems. Further research is critically needed in instances when few or no other options are available to ensure the economic viability of farming operations while addressing long-term soil quality concerns.
Italian Journal of Agronomy; https://doi.org/10.4081/ija.2021.1865
Specialty crop herbicides are not a target for herbicide discovery programs and many of these crops do not have access to relevant herbicides. High‐value fruit and vegetable crops represent high potential liability in the case of herbicide‐induced crop damage and low acres for revenue. Labor shortages and higher manual weeding costs are an issue for both conventional and organic specialty crop growers. Robotic weeders are promising new weed control tools for specialty crops, because they are cheaper to develop and, with fewer environmental and human health risks, are less regulated than herbicides. However, many of the robotic weeders are too expensive for small growers to use. In the future greater investment into robotic weeders for small scale growers will be important. The Clearpath robotics platform Husky may provide a cheap and autonomous way to control weeds in small diversified specialty crop farms. Being able to work autonomously in multiple soil moisture environments is the driving factor behind optimizing the Husky platform for weed control. Research has been conducted to evaluate the impact of soil moisture and mechanical actuator on mobility and weed control. Though weed control was not commercially acceptable in these studies, future optimizations to the Husky robotics platform have the potential to achieve commercial success.
Italian Journal of Agronomy; https://doi.org/10.4081/ija.2021.1850
A field study was carried out in 2017 and 2018 in two Italian rice farms (at Livorno Ferraris and Rovasenda) to assess the effect of using cover crops as green mulching on weed control and rice yield. In each site, three different rice fields were sown after rice harvest with either Vicia villosa, Lolium multiflorum, or a mixture of both (V. villosa 40% + L. multiflorum 60%); at Rovasenda a small percentage of Brassica napus and Triticale was also present in the mixture. An additional field at both sites without cover crop was considered as a control reference. Rice was broadcasted sown within the cover crop in May. After few days, the cover crop was terminated in half of each field using a roller-crimper, while in the other half it was terminated by shredding. Within 10 days, the fields were flooded for about a week to promote the degradation of the cover crop biomass. Then, the fields were cultivated in flooding conditions without further weed control. Weed density and weed cover were evaluated thrice during the growing season. At harvest, rice yield and harvest index were determined. Mixed nested ANOVAs were performed for each site to assess the effect of cover crop species, termination technique, and the interaction between cover crop and year. L. multiflorum showed a high biomass before termination, while V. villosa had a more variable development. At Rovasenda, V. villosa growth was limited because of the combination of scarce emergence due to sod-seeding and frost damage. In general, green mulching significantly affected weed density. The best weed suppression was observed with L. multiflorum and mix at Rovasenda, with values of weed density 5 t ha-1) was observed in 2018 in the shredded mixture at Rovasenda and in V. villosa at Livorno Ferraris in 2017. Generally, control fields showed lower yields (1-3 t ha-1) at both sites. The termination methods did not significantly affect both weed density and rice yield. The results highlighted that green mulching could reduce weed infestations, even though alone is not able to completely avoid weed development. Some critical issues of the technique were observed, such as the need of a good cover crop establishment, that eventually results in abundant biomass production and significant weed suppression. Highlights - Green mulching reduces weed pressure but it should be integrated with other weed control techniques. - Hairy vetch showed poor establishment because of the combination of scarce emergence due to sod-seeding and low temperatures. - Italian ryegrass was more tolerant to low temperatures and showed a good cover that contained weed growth. - Cover crop mixture showed variable results with higher suppression probably related to the number of cover crop species present in the mixture. - The termination methods (crimping and shredding) did not affect weed density and rice yield.
Italian Journal of Agronomy; https://doi.org/10.4081/ija.2021.1869
Cover crops are essential tools in agroecosystems for reducing the reliance on synthetic inputs and associated environmental risks. Alongside their benefits to soil fertility, cover crops can control weeds by their competitive and allelopathic attributes. Laboratory and field experiments were conducted to assess the allelopathic potential of two cover crop species, rye (Secale cereale L.) and squarrose clover (Trifolium squarrosum L.), alone or in mixture, on seed germination and growth of arable weeds. Aqueous extracts of the two cover crops and their mixture were tested in a bioassay on Conyza canadensis (L). Cronq., Amaranthus retroflexus L. and Digitaria sanguinalis (L.) Scop. In vitro effects of aqueous extracts varied in a dose-dependent manner, with cover crops and weed species. All three extracts were able to reduce the germination of A. retroflexus (-87%) considerably. Inhibitory effects by rye and mixture extracts on radicle growth of all weed species ranged between 51 and 82%. Rye extract was the best at reducing shoot length of C. canadensis and D. sanguinalis (-39 to 44%), while squarrose clover was more effective on A. retroflexus (-79%). Plant extracts also delayed the germination time of weed species with substantial effect of the mixture on C. canadensisseeds. In the field experiment, no significant weed suppression was provided by cover crop residues incorporated as green manure compared to control plots, despite tillage being more effective in reducing weed density. Still, the cover crop mixture mulch controlled weed emergence significantly better than single cover crop mulches. The chemical characterization of cover crop residues, both shoots and roots, revealed a notable richness of allelopathic phenolic acids and flavonoids, that through slow decomposition may constitute potential natural herbicides. From the analysis of the aqueous extracts, other non-analyzed and/or unidentified water-soluble allelopathic compounds should underlie the phytotoxicity observed in vitro, at least for rye. For cover crop mixture, positive interactions among plant materials leading to a better release of allelochemicals and weeding effectiveness are discussed according to chemical profiles and field data. Our study demonstrated the allelopathic activity of the cover crops and their potential to be included in weed management strategies according to cropping system needs. Additional trials are needed to confirm the performance of cover crop residues under field conditions. Highlights - Rye and squarrose clover are cover crops with potential allelopathic effects. - Aqueous extracts of residues of rye, squarrose clover and their mixture reduced and/or slowed weed germination of A. retroflexus and C. canadensis in in vitro bioassays. - The aqueous extracts, depending on the concentration of residues, had inhibitory effects on radicle and shoot growth of A. retroflexus, C. canadensis and D. sanguinalis. - Under field conditions, mulch of a mix of rye and squarrose clover suppressed weeds better than the single species.
Italian Journal of Agronomy, Volume 16; https://doi.org/10.4081/ija.2021.1810
Soil salinity threatens agricultural production worldwide by constraining plant growth and final crop yield. The early stages are most sensitive to salinity, in response to which salicylic acid (SA) has demonstrated beneficial effects in various plant species. Based on this, a maize (Zea mays L.) pot experiment was set up combining three levels of soil salinity (0, 6 and 12 dS m–1), obtained through NaCl addition, with three levels of SA (0, 300 and 600 mM), applied by leaf spraying 20 days after seedling emergence. Fifteen days later, the following traits were assessed: morphology (plant height, leaf number), growth (root and shoot dry weight), leaf water status [relative water content (RWC), electrolyte leakage (EL)], pigments (chlorophyll a and b, carotenoids, anthocyanin), antioxidant enzymes (peroxidase, catalase, ascorbate peroxidase, vitamin C), oxidative stress markers (H2O2, malondialdehyde), osmo-regulating compounds (free amino acids, soluble proteins and sugars, proline), hormones [indole-3-acetic acid, gibberellic acid (GA), abscisic acid (ABA), ethylene], element (Na, K, Ca, Mg and Cl) concentration and content in roots, stem and leaves. Salinity severely affected maize growth (–26% total dry weight), impaired leaf water status (–31% RWC), reduced photosynthetic pigments, enhanced all antioxidant enzymes and oxidative stress markers, two osmo-regulating compounds (soluble sugars and proline) out of four, and all hormones except GA. SA was shown effective in containing most of the stress effects, while supporting plant defences by upgrading antioxidant activities (reduced oxidative stress markers), increasing cell membrane stability (–24% EL) and leaf water status (+20% RWC), and reducing plant stress signalling (–10% ABA and -20% ethylene). Above all, SA contrasted the massive entry of noxious ions (Na+ and Cl–), in favour of K+, Ca2+ and Mg2+ accumulation. Lastly, salicylic acid was shown beneficial for maize growth and physiology also under non-saline condition, suggesting a potential use in normal field conditions. Highlights - Foliar applied salicylic acid alleviated salinity effects on maize growth at early plant stage. - Salicylic acid improved leaf water status, chlorophyll content, and strengthened anti-oxidant enzymes under salinity. - Salicylic acid reduced oxidative stress markers while enhancing osmo-regulating and hormonal responses to salinity. - Salicylic acid hampered Na and Cl entry and translocation to above ground organs, preserving leaf cell membrane integrity. - Salicylic acid was shown beneficial for maize growth and physiology also under non-saline conditions.
Italian Journal of Agronomy, Volume 16; https://doi.org/10.4081/ija.2021.1870
Changmaogu is a very rare and endangered rice landrace cultivated in a very limited area by Lama people, a branch of Bai ethnic group in Lanping County, Yunnan, China. No study on this precious landrace had been reported. This study was intended to explore the genetic diversity so as to develop strategy for conserving Changmaogu. The Changmaogu samples were compared with other three varieties (Hejing 16, Nipponbare and Hongxiangmi), using 24 pairs of SSR markers. Among all varieties, Changmaogu showed the richest genetic diversity. Cluster analysis also showed that Changmaogu can be distinguished in the genetic distance of 0.68. These data suggested that landrace is of great significance for the selection of rice varieties under the harsh environment and the acquisition of parents in the breeding work. The high altitude, low temperature and complex microbial community may be the important factors of genetic diversity in Changmaogu. The influence of ‘agriculture-processing-marketing’ mode of landraces should be continuously tracked. The strategy for conservation and sustainable development of Changmaogu was proposed in the present paper. Highlights - Changmaogu, a very rare and endangered rice landrace cultivated in a very limited area by Lama people, has more abundant genetic diversity than the three compared cultivars-Hejing 16, Nipponbare and Hongxiangmi, which enables it to adapt to changing environmental conditions, ensures local food supply and agricultural economic development, and makes it an effective supplement to the rice gene pool. - The result of UPGMA clustering analysis based on genetic distance led to the formation of three clusters, which Changmaogu had further genetic distance compared with hybrid rice Hejing 16 and rice parents Nipponbare, further revealing the utilization potential of Changmaogu in crop breeding. - The genetic diversity of Changmaogu and Hongxiangmi was compared to reveal the important position of Changmaogu in the protection of landrace, and to explore the potential impact of commercial activities on the genetic diversity of landrace. - According to the case of Changmaogu, this paper puts forward reasonable and effective strategies for the protection, which can be derived and applied to the protection of other landraces.
Italian Journal of Agronomy, Volume 16; https://doi.org/10.4081/ija.2021.1960
To: Pier Paolo Roggero, Editor-in-Chief, Italian Journal of Agronomy, and Michele Moscato, PAGEPress Publications, Publisher We take note of your communication following the report by Dr. Paolo Bazzoffi regarding the copyright infringement of the paper ‘Effectiveness of the GAEC cross-compliance standard short-term measures for runoff water control on sloping land (temporary ditches and grass strips) in controlling soil erosion’ (Authors: Bazzoffi, Ciancaglini, Laruccia), that can be found at the following address: https://www.agronomy.it/index.php/agro/ article/view/ija.2011.6.s1.e3. The title of the retracted publication is: ‘Temporary ditches are effective in reducing soil erosion in hilly areas. An evaluation with the RUSLE model’ (Authors: Francaviglia, Neri), that can be found at the following address: https://www.agronomy.it/index. php/agro/article/view/1762). The undersigned authors thoroughly agree with the points raised by Dr. Paolo Bazzoffi in relation to the copyright infringement. In particular, we agree that the original paper ‘Effectiveness of the GAEC cross compliance standard short-term measures for runoff water control on sloping land (temporary ditches and grass strips) in controlling soil erosion’ was not clearly indicated as original data source in the paper ‘Temporary ditches are effective in reducing soil erosion in hilly areas. An evaluation with the RUSLE model’. We also recognize that we did not give credit to Dr. Paolo Bazzoffi of the original methodology, particularly: i) the original materials and methods; ii) the GIS elaboration; and iii) the original data and results. The authors declare that: - they considered the opportunity to review the data published by Dr. Bazzoffi et al. shown in Table 7 of their original publication after a data re-elaboration, as shown in Table 3 of the publication to be retracted, with the aim to provide a statistical comparison of erosion in hilly agricultural land among the Italian Regions, as well as introducing an evaluation of the weight of the parameters implemented in the RUSLE model using a multiple regression technique; - they are aware of not having adequately recognized the copyrights of Dr. Bazzoffi and co-authors Ciancaglini and Laruccia. For these reasons, and as requested, we retract the paper ‘Temporary ditches are effective in reducing soil erosion in hilly areas. An evaluation with the RUSLE model’ from publication. We apologize to Dr. Bazzoffi, Dr. Ciancaglini and Dr. Laruccia for the unpleasant inconvenience caused. We also take the opportunity to thank Dr. Paolo Bazzoffi for coordinating the EFFICOND and MONACO projects, in which we participated in various work packages, offering the possibility of a valuable and constructive work experience. Sincerely, Rosa Francaviglia and Ulderico Neri
Italian Journal of Agronomy, Volume 16; https://doi.org/10.4081/ija.2021.1820
The sustainability of warm-season turfgrass species in winter dormancy is a major concern in Mediterranean ecology. The concept of overseed a lawn has been still new for many developing countries such as Turkey as part of a regular maintenance. Therefore, a 2-year study was conducted at the experimental fields of Ege University, Izmir/Turkey during 2014-2016 years to compare the effects of four different overseeding times (September 15, September 30, October 15 and October 30) on four warm season turfgrass species (Cynodon dactylon cv. SR9554, Cynodon dactylon × Cynodon transvaalensis cv. Tifway-419, Paspalum vaginatum cv. Sea Spray and Zoysia japonica cv. Zenith) by measuring visual turf quality (1-9 score) and some related characteristics as texture (mm), cover (1-9 score), weed infestation (1-9 score) and colour (1-9 score). ‘50% cv. Troya+50% cv. Esquire’ perennial ryegrass (Lolium perenne L.) mixture was used for overseeding in trial. According to results, visual turf quality performance of 6.0 scores and above were obtained from all treatments. We concluded that October 15 should be most suitable time for overseeding applications. Additionally, L. perenne L. can be practiced successfully in Mediterranean region in order to eliminate the concerns of warm-season turfgrasses in the winter dormancy period observed in cold temperatures. Highlights - No gaps were formed in plots and high coverage degrees were maintained during overseeding periods in all treatments. - Homogeneous spring transition was occurred from Lolium perenne L. to warm-season turfgrass species in all overseeding times. - Visual turf quality performance of 6.0 scores and above which is acceptable level were obtained from all overseeding times. - Better results were obtained from overseeding applications on Paspalum vaginatum and Cynodon dactylon × Cynodon transvaalensis. - The different results among the warm-season turfgrass species can provide effective information for future research studies.
Italian Journal of Agronomy, Volume 16; https://doi.org/10.4081/ija.2021.1843
The ongoing climate change, which is threatening grassland agroecosystems throughout Europe, is also evident in the Italian grasslands. These systems, often located in marginal areas, are species-rich ecosystems characterized by variable, and often unreliable, grass and forage production and strongly dependent on interactions between climate, soil and agricultural management practices (e.g. land abandonment, lack of investments on innovation, stocking rates reduction, etc.), making them very sensitive and vulnerable to climate change. This review draws from the scientific literature the impacts of current and expected climatic changes on grassland and forage crop systems framed in three different bio-climatic zones of Italy, namely the Alpine, Continental and Mediterranean, and focussing on: i) grassland biodiversity and vegetation; and ii) forage production and quality. The main aims of this review are to: i) revise the existing literature in the domain, highlighting different or common trends among different Italian biogeographical regions; ii) provide information on the main climatic impacts analysed and drivers involved in the studied evolutions; and iii) point out the knowledge gaps currently pending in order to hypothesize the future scenarios of research in this sector. Even if this review has pointed out differences in approaches, adopted methodologies and purposes of conducted researches, some common trends can be highlighted, though located in three different environments. Expected warming and modification on rainfall pattern will produce deep changes in vegetation of grassland types, with reduction or the disappearance of cold tolerant species and a spread of xeric/thermophilus ones and shrubby vegetation and with a general upward shift of vegetation types in mountain areas. Moreover, a general reduction of aboveground biomass is expected, as summer droughts is considered a main driver able to force grassland productivity. Finally, warming and rainfall reduction are considered the main factors able to reduce forage quality and palatability of grasslands, as a consequence of reduction of nitrogen content in the available biomass and of the higher spread of less unpalatable species and shrubs. The hypothesis is that the information gained from this review can provide insights on the current level of knowledge on the expected impacts of climate change on Italian grassland systems, and support the development of policy strategies for adaptation at national level. Highlights - This review highlights grassland systems responses to climate change in the Alpine, Apennine and Mediterranean areas of Italy.- Future climate will determine deep changes in grassland composition, extension and productivity. - Droughts is considered the main factor affecting forage quality and palatability.- Further research is needed to understand climate change impacts on grassland vegetation in the Mediterranean.