Effects of mulching on above and below ground pests and beneficials in a green onion agroecosystem

Abstract

In 2013 and 2014, different mulching systems were investigated for their potential to suppress above and below ground pests, and enhance beneficial arthropods and soil health in green onion (Allium cepa) plantings. Three types of mulch systems (organic, living and solarization mulch) were evaluated and compared. Green onions were grown in four pre-plant treatments: 1) organic mulch generated by flail mowing a sunn hemp (Crotalaria juncea) cover crop (SH) followed by a no-till cropping system, 2) soil solarization (Sol), 3) sunn hemp-solarization mulch in which the sunn hemp was incorporated into the soil followed by soil solarization (SHSol), and 4) bare ground with insecticides (BG). Sol, SHSol and BG were practiced in conventional tilled system. SH (in 2013 and 2014) and SHSol (in 2014) treatments included strips of buckwheat and cowpea along the crop border to serve as living mulch or insectary plants. Green onion plants in SH had lower thrips and leaf miners damage than other treatments in both study years. When insectary borders were added to SHSol in 2014, thrips and leaf miners damages were also reduced in SHSol compared to Sol and BG. Incidence of purple blotch was reduced in SH and SHSol treatments in 2014. The SH treatment contained an increased abundance and richness of detritivores, predatory arthropods, parasitoids and beneficial free-living nematodes (particularly bacterivores and fungivores). Although weeds and initial populations of plant-parasitic nematodes were lower in solarization (Sol, SHSol) than other treatments, green onion yield was greatest in SH organic mulch systems in both study years. Overall, the integration of surface organic, living and solarization mulches into a green onion agroecosystem provided multiple ecosystem services including suppression of above and below ground pest organisms.

A Review of Prospective Biocontrol Agents and Sustainable Soil Practices for Bulb Mite (Acari: Acaridae) Management

“…populations, it has been observed that the use of conservation strategies such as organic mulching can increase soil diversity and ultimately decrease populations of other pest organisms or their negative effect on crop plants. In several cases, the use of organic amendments has been shown to reduce populations of organisms considered to be pests such as phytoparasitic nematodes (e.g., [74][75][76][77][78]), and phytophagous mites (e.g., [79]), as well as damage by some phytophagous insects (e.g., [80]), and the increase of organisms considered beneficial such as free-living nematodes (e.g., [74,76,78,80]) and predatory mites (e.g., [74,75,79]). At laboratory level and on a small scale, it has been shown that, for some organisms such as some predatory mite species, the addition of alternative such as free-living nematodes can enhance their survival and reproduction and, in turn, their densities [81][82][83], which would be reflected in an increase in the control of phytophagous organisms [82,83].…”

“…increase of organisms considered beneficial such as free-living nematodes (e.g., [74,76,78,80]) and predatory mites (e.g., [74,75,79]). At laboratory level and on a small scale, it has been shown that, for some organisms such as some predatory mite species, the addition of alternative such as free-living nematodes can enhance their survival and reproduction and, in turn, their densities [81][82][83], which would be reflected in an increase in the control of phytophagous organisms [82,83].…”

Intensificação de sistemas de produção de palma forrageira por meio de consorciação rotativa com gramíneas, leguminosas e oleaginosas: uma revisão

“…A cobertura morta visa minimizar as perdas de água do sistema para a atmosfera, com a inserção de materiais orgânicos (palhadas, resíduos vegetais, etc.) ou inorgânico (plástico) sobre o solo, buscando-se aumentar o rendimento das culturas agrícolas (Quintanilla-Tornel et al, 2016;Alves et al, 2018).…”

“…Com o intuito de potencializar o aproveitamento da água aplicada no sistema, a inserção de cobertura morta sobre o solo contribui para a redução das percas de água pela evaporação, além de disponibilizar nutrientes com sua mediante decomposição para o solo, e com isso promovendo ecossistemas mais sustentáveis para a produção vegetal no semiárido brasileiro (Quintanilla-Tornel et al, 2016;Alves et al, 2018).…”

The Impact of Agricultural Practices on Soil Organisms: Lessons Learnt from Market-gardens

“…Mulching is a form of cover crops that remains on the surface of the soil. It can be inorganic or organic material (plastic, straw, cover crop residues or live plant) and it is used to prevent soil erosion, increase water retention, pest control and weed control [10,68,69,70]. However, few of the surveyed farmers are using this method.…”