Influence of Compaction and Subsoil Tillage on Soil Conditions and Pink Eye

Abstract

A densely compacted soil layer has been a prevalent feature of the vegetable crop production region of Central Wisconsin, resulting in poor water drainage, increased susceptibility to tuber disease, and reduced yield and quality in potatoes. Subsoil tillage has been implemented on a widescale for management of problems associated with compacted soil layers. Pink eye is a tuber disorder that causes storage and processing losses. Periods of moisture stress and increased hill temperatures have been linked to pink eye incidence, but the cause of this disorder is unknown and few specific management recommendations exist. The goals of this work were to quantify the impact of compacted soils and subsoil tillage on development of potato pink eye. Small plot experiments were conducted to quantify response of soil conditions and potato pink eye to soil compaction and subsoil tillage. Compacted soils resulted in higher volumetric soil water content and extended periods of free water, especially after substantial precipitation events. Subsoil tillage allowed for more rapid movement of water following large precipitation events decreasing periods of free water. More compacted soils also had higher soil temperatures. Subsoil tillage delayed the development and progression of pink eye symptoms, but did not influence overall incidence. Increased soil moisture and temperature corresponded with more rapid development of pink eye in compacted and conventionally tilled soils. This research suggests subsoil tillage may be useful in reducing the severity of pink eye symptoms by alleviating compacted subsoil layers that limit water drainage. In addition, prevention of compaction reduced soil temperatures which limited pink eye development.Resumen Una capa de suelo densa y compacta ha sido la característica prevalente en la región de producción de hortalizas de Wisconsin Central, dando como resultado un drenaje deficiente, incremento de la susceptibilidad del tubérculo a las enfermedades y reducción del rendimiento y calidad de las papas. La labranza del subsuelo ha sido implementada en gran escala para el manejo de problemas asociados con capas de suelo compacto. El ojo rosado es un desorden del tubérculo que causa pérdidas durante el almacenaje y procesamiento. Los periodos de estrés de humedad e incremento de la temperatura del surco han sido relacionados con la incidencia de ojo rosado, pero se desconoce la causa de este desorden y existen pocas recomendaciones de manejo. Las metas de este trabajo fueron cuantificar el impacto de los suelos compactos y la labranza del subsuelo en el desarrollo del ojo rosado. Se realizaron experimentos en parcelas pequeñas para cuantificar la respuesta de las condiciones del suelo y ojo rosado de la papa, a la compactación del suelo y labranza del subsuelo. Los suelos compactos resultaron en contenido volumétrico de agua más alto y extensos periodos de agua libre especialmente después de una fuerte lluvia. La labranza del subsuelo permitió el movimiento más rápido del agua después de una lluvia fuer...

Relationship Between Pink Eye Symptoms and Cell Damage in the Tuber Periderm and Cortex

“…Because of the confusion and lack of information, little progress has been made in identifying the cellular and physiological effects of PE and finding means to prevent it. Copas et al (2008) demonstrated that increased soil temperatures and moisture were correlated to the development of PE. Lulai et al (2006) hypothesized that the hypoxic or anoxic conditions and high soil temperatures often associated with pink eye can result in higher oxygen demand and the death of periderm cells, in particular phellogen cells required for the maintenance and expansion of the periderm during tuber growth.…”

“…PE symptoms progress from ephemeral pink discolorations around tuber eyes to watersoaked or dried and cracked "corky-patch" periderm (Secor 1988). Corky patch, or "bullhide" symptoms can complicate skin removal during processing and advanced PE may lead to bud-end rot, either at harvest or during storage (Copas et al 2008;Secor and Rouse 1992).…”

“…Although no one has been able to recreate PE under controlled conditions, it has been associated with high temperatures followed by excessive moisture and with early dying and early vine senescence (Copas et al 2008;Secor 1988;Secor and Gudmestad 2001;Secor and Rouse 1992). While some reports have linked PE to either Pseudomonas fluorescens (Folsom and Friedman 1959) or Verticillium spp.…”

“…Compromised native periderm or its absence leaves cells susceptible to subsequent infection by bacteria and fungi. Copas et al (2008) demonstrated progression of PE to bud end rot during the growing season prior to harvest and Lulai et al (2006) found that Rhizoctonia can invade PE-afflicted tissue.…”

“…Specific objectives included (1) evaluation of the progression of visible PE symptoms, (2) documentation of cellular changes related to the progression of PE symptoms and aberrant suberization in PE affected tissues, (3) determination of the viability of cells within PE affected tissues, and (4) immunolocalization of pectin and extensin epitopes in cell walls of PE-afflicted tissue. Copas et al (2008). Tubers were sampled every other week from early July through harvest from six plants in 32 plots (60 to 120 tubers per plot) and evaluated for pink eye symptoms.…”