La vegetazione infestante del mais ha subito importanti fenomeni evolutivi, con l’aumento della diffusione di alcune malerbe e con l’introduzione o la perdita di importanza di altre specie. Questo fenomeno è il risultato delle numerose innovazioni tecnologiche che hanno interessato la coltura e del diserbo chimico in particolare. La situazione degli inerbimenti attualmente presenti nel mais appare alquanto complessa e differenziata fra le varie realtà dei sistemi maidicoli del nostro paese. In termini generali, sono da considerare ubiquitarie specie quali: Sorghum halepense, Echinochloa crus–galli, Digitaria sanguinalis, Lolium spp., Paniucum dichotomiflorum e Setaria spp. , tra le graminacee, e Chenopodium album, C. polyspermum Solanum nigrum, Amaranthus retroflexus, Polygonum aviculare, P. persicaria, Abutilon theophrasti, Bidens spp., Xanthium strumarium, Convolvulus arvensis, Calystegia sepium e Cirsium arvense tra le infestanti a foglia larga. Le numerose possibilità di lotta offerte dall’industria dei prodotti agrochimici consentono di pianificare interventi in diverse fasi del ciclo colturale (pre-semina, pre-emergenza e post-emergenza) e di effettuare interventi specifici per la risoluzione di situazioni malerbologiche particolari. Numerosi mezzi agronomici, meccanici e fisici, agendo direttamente o indirettamente sulla popolazione infestante, possono essere efficacemente integrati con il mezzo chimico o rappresentare una valida alternativa ad essi, in particolare nelle aree ad indirizzo biologico. This paper describes the role and importance of weed management in Italian maize fields. The weed dynamics of the last decades is depicted by describing the main technological innovations adopted by farmers. In particular, a key role has been played by chemical weed control, which greatly contributed to the mechanization of the crop and reduction of manpower required. The introduction of atrazine in 1964 led in few years to the adoption of chemical weed control on most of the Italian maize area and the repeated use of this triazine herbicide induced the selection of resistant populations of Amaranthus spp., Solanum nigurm and Chenopodium album in several areas. At the same time, the weed population structure showed several alterations, with the selection of a flora mainly constituted by Sorghum halepense, annual grasses (Echinochloa spp., Setaria spp., Digitaria sanguinalis, and Panicum dichotomiflorum) and perennial broad-leaf weeds (Convolvulus arvensis, Bilderdykia convolvulus). The spread of species difficult to control and highly competitive, as well as several environmental concerns (which were the main reasons for abandoning atrazine from the end of ‘80s) led to a deep revision of all the weed management programs. New importance was gained by agronomical, mechanical and physical weed control in the last few years. The adoption of rotation, in particular, can prevent the selection of a specific flora, and promote annual species that show poor competitive capacity and low seed dormancy. The rotation also allows to get rid of problematic maize weeds by controlling them in the rotational crops (such as S. halepense in soyabean). Despite the availability of a large number of herbicides applicable in post-emergence, the most common weed management program (at least 95% of the area) is based on a pre-emergence treatment, followed (if required) by a post-emergence treatment or hoeing. The environment sustainability of weed control in maize is improved by the availability of new equipments for mechanical weed control, that are applicable both in integrated and non-chemical weed control programs.
La gestione della flora infestante nel mais
VIDOTTO, Francesco;FERRERO, Aldo
2005-01-01
Abstract
La vegetazione infestante del mais ha subito importanti fenomeni evolutivi, con l’aumento della diffusione di alcune malerbe e con l’introduzione o la perdita di importanza di altre specie. Questo fenomeno è il risultato delle numerose innovazioni tecnologiche che hanno interessato la coltura e del diserbo chimico in particolare. La situazione degli inerbimenti attualmente presenti nel mais appare alquanto complessa e differenziata fra le varie realtà dei sistemi maidicoli del nostro paese. In termini generali, sono da considerare ubiquitarie specie quali: Sorghum halepense, Echinochloa crus–galli, Digitaria sanguinalis, Lolium spp., Paniucum dichotomiflorum e Setaria spp. , tra le graminacee, e Chenopodium album, C. polyspermum Solanum nigrum, Amaranthus retroflexus, Polygonum aviculare, P. persicaria, Abutilon theophrasti, Bidens spp., Xanthium strumarium, Convolvulus arvensis, Calystegia sepium e Cirsium arvense tra le infestanti a foglia larga. Le numerose possibilità di lotta offerte dall’industria dei prodotti agrochimici consentono di pianificare interventi in diverse fasi del ciclo colturale (pre-semina, pre-emergenza e post-emergenza) e di effettuare interventi specifici per la risoluzione di situazioni malerbologiche particolari. Numerosi mezzi agronomici, meccanici e fisici, agendo direttamente o indirettamente sulla popolazione infestante, possono essere efficacemente integrati con il mezzo chimico o rappresentare una valida alternativa ad essi, in particolare nelle aree ad indirizzo biologico. This paper describes the role and importance of weed management in Italian maize fields. The weed dynamics of the last decades is depicted by describing the main technological innovations adopted by farmers. In particular, a key role has been played by chemical weed control, which greatly contributed to the mechanization of the crop and reduction of manpower required. The introduction of atrazine in 1964 led in few years to the adoption of chemical weed control on most of the Italian maize area and the repeated use of this triazine herbicide induced the selection of resistant populations of Amaranthus spp., Solanum nigurm and Chenopodium album in several areas. At the same time, the weed population structure showed several alterations, with the selection of a flora mainly constituted by Sorghum halepense, annual grasses (Echinochloa spp., Setaria spp., Digitaria sanguinalis, and Panicum dichotomiflorum) and perennial broad-leaf weeds (Convolvulus arvensis, Bilderdykia convolvulus). The spread of species difficult to control and highly competitive, as well as several environmental concerns (which were the main reasons for abandoning atrazine from the end of ‘80s) led to a deep revision of all the weed management programs. New importance was gained by agronomical, mechanical and physical weed control in the last few years. The adoption of rotation, in particular, can prevent the selection of a specific flora, and promote annual species that show poor competitive capacity and low seed dormancy. The rotation also allows to get rid of problematic maize weeds by controlling them in the rotational crops (such as S. halepense in soyabean). Despite the availability of a large number of herbicides applicable in post-emergence, the most common weed management program (at least 95% of the area) is based on a pre-emergence treatment, followed (if required) by a post-emergence treatment or hoeing. The environment sustainability of weed control in maize is improved by the availability of new equipments for mechanical weed control, that are applicable both in integrated and non-chemical weed control programs.
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