Super absorbent polymer application in seeds and planting furrow: it will be a new opportunity for rainfed agriculture

Abstract

Brazil is the fourth largest grain producer in the world. Its agriculture is mainly rainfed, with two cropping seasons per year. While the first crop (i.e., spring/summer) receives greater precipitation, the second crop (i.e., autumn/winter) is associated with greater risk of crop failure mainly due to the low rainfall, suggesting that technologies that could optimize water use during that period are needed. Superabsorbent polymers (SAP) are used in the forestry sector to reduce seedling mortality and the frequency of irrigation of eucalyptus and pinus glue owing to their ability to increase water storage capacity in the soil. However, to our knowledge, very little is known about the use of SAP in annual agricultural crops. To this end, the effects of SAP, as a seed coat or applied in the planting grooves, on the initial development of sorghum seedlings under conditions of water deficit were evaluated in two experiments under greenhouse conditions. In experiment 1, sorghum seeds with and without SAP coating were seeded in trays and subjected to three irrigation intervals to induce water deficit. The percentage of emergence and emergence speed index were evaluated and, at 26 days after sowing, seedling height, number of leaves per plant, survival rate, and dry mass of shoot and root were evaluated. In experiment 2, the seeds of sorghum with and without SAP coating were sown in pots, with SAP applied in the planting grooves. At 30 days after sowing, the plant stand, number of leaves per plant, plant height, and dry matter mass of leaves, stem, and root were evaluated. The results showed that SAP applied both as a seed coat and in planting grooves increased seedling growth and dry mass of aerial parts at 26 days and 30 days for experiments 1 and 2, respectively. In addition, seed coating with SAP increased plant survival rate, but reduced the rate of seedling emergence in both experiments. Therefore, the use of SAP as a seed coat or applied in the planting groove has beneficial effects on the vegetative development of sorghum under low water conditions. Further research is needed to address the effect of SAP on seedling emergence. ResumoO Brasil é o quarto maior produtor de grãos no mundo. Sua agricultura é baseada em cultivos de sequeiro, com duas safras por ano. A segunda safra é a mais afetada, por estar associada à maiores riscos climáticos, principalmente pela baixa pluviosidade nos meses de janeiro à abril. Nesse sentido, tecnologias que otimizem o uso da água podem reduzir os riscos de quebra de safra. O uso de polímeros superabsorventes (PSA) vem sendo consolidado no setor florestal, visando reduzir a mortalidade de mudas e a frequência de irrigações de pegamento de eucalipto e pinus devido ao aumento da capacidade de armazenamento de água no solo. Entretanto, não há relatos sobre o uso do PSA em culturas anuais. O objetivo deste trabalho foi avaliar o efeito do PSA como revestimento de sementes e no sulco de plantio no desenvolvimento inicial de plântulas de sorgo sob condições de déficit hídrico....

Effects of insecticides applied in-furrow with superabsorbent polymer on peanut cultivars infected with Tomato spotted wilt virus

“…SAP has been used in agricultural applications before (Bai et al, 2013;de Barros et al, 2017;Bhardwaj et al, 2007;Busscher et al, 2009;Campos et al, 2015;Dehkordi 2016;Ekebafe et al, 2011;Hayat and Ali 2004;Pouci et al, 2008;Sojka and Lentz 1997), but to our knowledge, this was the first study to examine its utility in the peanut -Tomato spotted wilt virus system. Spotted wilt incidence in different cultivars and treatment regimens (in the absence of SAP) has been the subject of several prior studies (Branch et al, 2003;Culbreath et al, 2000;Culbreath et al, 2016;Drake et al, 2009;Herbert Jr. et al, 1991;Lynch et al, 1984;Marasigan et al, 2018).…”

“…Superabsorbent polymers (SAP) are currently used as soil conditioners and encapsulation devices for delivery of some pesticides (de Barros et al, 2017;Campos et al, 2015). Examples of SAP include cross-linked hydrophilic polymers; SAP utilize monomers of acrylamide, acrylic acid, and their salts potassium acrylate or sodium acrylate to absorb large quantities of liquid, 10 to 1000 times their original weight or volume, in a short period of time (Ahmed 2015;de Barros et al, 2017;Horie et al, 2004;Zohuriaan-Mehr and Kabiri 2008).…”

“…Superabsorbent polymers (SAP) are currently used as soil conditioners and encapsulation devices for delivery of some pesticides (de Barros et al, 2017;Campos et al, 2015). Examples of SAP include cross-linked hydrophilic polymers; SAP utilize monomers of acrylamide, acrylic acid, and their salts potassium acrylate or sodium acrylate to absorb large quantities of liquid, 10 to 1000 times their original weight or volume, in a short period of time (Ahmed 2015;de Barros et al, 2017;Horie et al, 2004;Zohuriaan-Mehr and Kabiri 2008). Examples of beneficial uses of SAP in agriculture include enhancing soil permeability and infiltration rates, soil aeration, water consumption, water use efficiency, microbial activity, and overall plant performance by reducing leaching and promoting root development (de Barros et al, 2017;Campos et al, 2015;Dehkordi 2016;Woodhouse and Johnson 1991).…”

“…Examples of SAP include cross-linked hydrophilic polymers; SAP utilize monomers of acrylamide, acrylic acid, and their salts potassium acrylate or sodium acrylate to absorb large quantities of liquid, 10 to 1000 times their original weight or volume, in a short period of time (Ahmed 2015;de Barros et al, 2017;Horie et al, 2004;Zohuriaan-Mehr and Kabiri 2008). Examples of beneficial uses of SAP in agriculture include enhancing soil permeability and infiltration rates, soil aeration, water consumption, water use efficiency, microbial activity, and overall plant performance by reducing leaching and promoting root development (de Barros et al, 2017;Campos et al, 2015;Dehkordi 2016;Woodhouse and Johnson 1991). In relation to water use, SAP also have potential to reduce irrigation frequency and associated costs by 50%, as well as erosion and runoff (de Barros et al, 2017;Campos et al, 2015;Dehkordi 2016;Woodhouse and Johnson 1991).…”

“…Examples of beneficial uses of SAP in agriculture include enhancing soil permeability and infiltration rates, soil aeration, water consumption, water use efficiency, microbial activity, and overall plant performance by reducing leaching and promoting root development (de Barros et al, 2017;Campos et al, 2015;Dehkordi 2016;Woodhouse and Johnson 1991). In relation to water use, SAP also have potential to reduce irrigation frequency and associated costs by 50%, as well as erosion and runoff (de Barros et al, 2017;Campos et al, 2015;Dehkordi 2016;Woodhouse and Johnson 1991).…”