CHEMICAL OPTIONS FOR THE CONTROL OF SILVERLEAF NIGHTSHADE (Solanum elaeagnifolium)

Abstract

Silverleaf nightshade is a difficult-to-control perennial weed. Field experiments were conducted in northern Greece to evaluate the control of silverleaf nightshade with POST applications of glufosinate (1,500 g a.i. ha-1), glyphosate (3,600 g a.i. ha-1), tembotrione (148.5 g a.i. ha-1), and a mixture of tembotrione plus bentazon (148.5 plus 1,440 g a.i. ha-1) at an early vegetative stage (plant height 10-15 cm) and at the beginning of flowering (plant height 30-50 cm). Glufosinate provided > 95% control of silverleaf nightshade from 7 to 39 days after treatment (DAT), regardless of the vegetative stage at herbicide application. Similarly, glyphosate provided up to 90% control around 39 DAT at either growth stage applied, exhibiting gradually increasing efficacy. Tembotrione alone controlled silverleaf nightshade 85% when applied at the early vegetative stage and 48% when applied at the beginning of flowering. The mixture of tembotrione plus bentazon applied at the beginning of flowering exhibited 74% control at 21 DAT; however, the control was decreased to 41% at 35 DAT. When the mixture was applied at the early vegetative stage, S. elaeagnifolium control was 61% at 23 DAT, which was decreased to 27% at 39 DAT. Glufosinate and glyphosate were found to be reliable options for control of silverleaf nightshade when applied at either weed growth stage; tembotrione could be also another reliable option, however, when applied only at an early vegetative stage. The results have significant implications for developing appropriate management practices for silverleaf nightshade, taking into account chemical options for preventing the evolution of herbicide resistance.

Are Mediterranean forest ecosystems under the threat of invasive species Solanum elaeagnifolium?

“…Solanum elaeagnifolium grows in a wide range of environmental conditions (Mekki 2007), tolerating relatively high temperatures (20-34 °C), low annual rainfall (250-600 mm - Stanton et al 2007), and saline conditions, and it thrives on poor organic matter soils (Uludag et al 2016, Gitsopoulos et al 2017. Taproots can penetrate the soil to depths of 2 m or more, a characteristic that enables plants to tolerate drought and outperform shallow-rooted vegetation, especially during summer dry periods.…”

“…For example, the allelopathic mechanisms can be incorporated in agro-ecosystems for weed control through several ways such as the inclusion of allelopathic crops in crop rotations, the use of their residues for cover cropping, or by selection of the most active allelochemicals to be used as bioherbicides ). In the case of S. elaeagnifolium, it may also be combined with current chemical control methods (Cambardella & Elliott 1992, Choudhary & Bordovsky 2006, Gitsopoulos et al 2017.…”

Biology, distribution and management of the globally invasive weed Solanum elaeagnifolium Cav (silverleaf nightshade): A global review of current and future management challenges

“…These herbicides can reduce S. elaeagnifolium in all vegetative forms (e.g., juvenile and mature plants), but is most effective when applied during the plants active growth stage between early spring to autumn (Table 1) Choudhary & Bordovsky, 2006;Eleftherohorinos et al, 1993;Gitsopoulos et al, 2017). Furthermore, a study by Gitsopoulos et al (2017) shows that tembotrione can kill S. elaeagnifolium when applied in the early life stage of the plant. To achieve successful control of any weed species it is important to limit seed production and any subsequent the success of such application (Chahal & Jhala, 2015;Gitsopoulos et al, 2017).…”

Development of a temperature-based seed germination model for silverleaf nightshade (Solanum elaeagnifolium)

“…The control of S. elaeagnifolium is highly challenging due to its vigorous vegetative growth and extensive root system (Qasem et al 2019). Although glyphosate and ammonium sulfate can provide effective control (Gitsopoulos et al 2017), the lack of selectivity of the two herbicides limits their usage for control scenarios such as preemergence and direct spraying. Other herbicides that have shown efficacy (e.g., imazapyr, aminopyralid, and picloram) are not suitable for agricultural purposes (Wu et al 2016).…”

“…Other herbicides that have shown efficacy (e.g., imazapyr, aminopyralid, and picloram) are not suitable for agricultural purposes (Wu et al 2016). Furthermore, mechanical control tools, such as tillage and cultivation, are not practicable for S. elaeagnifolium, because the use of mechanical machinery can break the root system and spread the propagules throughout the field (Gitsopoulos et al 2017;Qasem et al 2019;Wu et al 2016). These limitations create the need for novel ecologically based control approaches that can be integrated into the currently used control methods.…”