Reducing Fertilization for Cut Roses: Effect on Crop Productivity and Twospotted Spider Mite Abundance, Distribution, and Management

Abstract

Fertilization reduction could be a useful pest management tactic for floriculture crops if it reduced pest populations with little loss in crop yield and quality. We evaluated the response of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), to different fertilization levels for cut roses, Rosa hybrida L. 'Tropicana' and quantified fertilization effects on (1) management of T. urticae on roses, (2) abundance and distribution of T. urticae on roses, and (3) yield and quality of the cut rose crop. We tested two fertilization levels, 10% (15 ppm N) and 100% (150 ppm N) of the recommended level for commercial production, and three control methods: no control measure; a predatory mite, Phytoseiulus persimilis Athias-Henriot; and a miticide, bifenazate. Combinations of both bottom up (fertilization) and top down (biological or chemical control) tactics provided a greater degree of T. urticae control than either tactic alone. Rose productivity was reduced with fertilization at 10% of the recommended level; therefore, we conducted studies with T. urticae on roses fertilized with 33% (50 ppm N), 50% (75 ppm N), and 100% (150 ppm N) of the recommended level. Mean numbers of T. urticae and T. urticae eggs per flower shoot were twice as high on roses fertilized with 100 versus 33% or 50% of the recommended level. Number of rose leaves and total leaf area infested by T. urticae were similar at all fertilization levels. Cut rose yield and marketability were not compromised on plants fertilized with 50% of the recommended level.

Efecto de Tetranychus urticae Koch en la calidad del tallo floral de 15 cultivares de rosa

“…En primavera de 2010 la temperatura promedio fue muy similar production cycles attributed to an increase in them. Another environmental factor that can affect mite population growth is the fertilization of the plant (Chow et al, 2009;Flores et al, 2011).…”

“…Otro factor ambiental que también puede afectar el crecimiento poblacional del ácaro es la fertilización de la planta (Chow et al, 2009;Flores et al, 2011).…”

“…también pueden influir en la atracción o repelencia del ácaro (Graham et al, 2008;Mumm y Dicke, 2010;Flores et al, 2011), todos dentro de una compleja relación entre parasito y huésped que debe explorarse individualmente (Hernández et al, 2002;Vivanco et al, 2005). Todos estos elementos pueden ser criterios complementarios en el manejo integral del cultivo y en mejoramiento genético (Chow et al, 2009). Recientes estudios reportan, además del manejo ambiental, el uso de compuestos volátiles de hojas de plantas como Cleome gynandra L./Gynandropsis gynandra (L.) Briq.…”

“…can also influence attracting or repelling mite (Gaham et al, 2008;Mumm and Dicke, 2010;Flores et al, 2011), all within a complex relationship between parasite and host must individually explored (Hernandez et al, 2002;Vivanco et al, 2005). All these elements can be complementary criteria in integrated crop management and genetic improvement (Chow et al, 2009). Recent studies, in addition to environmental management, report the use of volatile compounds from plant leaves as Cleome gynandra L./ Gynandropsis gynandra (L.) Briq.…”

Smart-use of fertilizers to manage spider mites (Acari: Tetrachynidae) and other arthropod pests

“…They found that the leaf content of phosphorous in cut roses (Rosa hybrida L) increased in response to increased nitrogen fertilization, but this increase did not cause significant increase in population densities of spider mites. However, Chow et al (2009) found that spider mite densities were positively correlated with levels of nitrogen fertilization. Chen et al (2007) found a positive correlation between nitrogen and phosphorous concentrations in three foliage strata of ivy geranium, Pelargonium peltatum (L.) and within-plant distribution of spider mites.…”