Cultivar response to fungicide application in relation to rice blast control, productivity and sustainability

Abstract

-Four field trials were conducted, from 1995 to 1997, with the objective of studying the response of four upland cultivars to foliar fungicide application in relation to panicle blast control, grain yield and sustainability. Differential disease control and yield response of cultivars to fungicide treatment were obtained. Losses in grain yield of cultivars IAC 202, Caiapó, Rio Paranaíba and Araguaia due to panicle blast were 44.8%, 27.4%, 24.4% and 18.2%, respectively. Two applications of tricyclazole or benomyl controlled panicle blast, as indicated by lower values of disease progress curve and relative panicle blast severity, and increased grain yield of the cultivar IAC 202. The losses in 100 panicle grain weight and grain yield were significantly reduced by 22.3% and 25.1% in IAC 202 and 23.6% and 20.5% in Caiapó, respectively, with two sprays of tricyclazole. Sustainable value index for yield was maximum with two applications of tricyclazole (0.59), followed by one application at booting (0.46) and at heading (0.40) in cultivar IAC 202. Results showed no yield response of the cultivars Rio Paranaíba and Araguaia to fungicide applications for panicle blast control.Index terms: Oryza sativa, yield factors, pest control, chemical control. Resposta de cultivares de arroz à aplicação de fungicidas em relação ao controle da brusone nas panículas, produtividade e sustentabilidadeResumo -Foram realizados quatro experimentos no campo, de 1995 a 1997, com o objetivo de estudar a resposta das cultivares de arroz de terras altas à aplicação de fungicidas foliares, em relação ao controle da brusone nas panículas, produtividade e sustentabilidade. Foram obtidas respostas diferenciais das cultivares às aplicações de fungicidas quanto ao controle da brusone e produtividade. As perdas em produtividade, causadas pela brusone, nas panículas, foram de 44,8%, 27,4%, 24,4% e 18,2% nas cultivares IAC 202, Caiapó, Rio Paranaíba e Araguaia, respectivamente. Os valores da área sob curva de progresso da doença e da severidade relativa da brusone nas panículas foram menores, resultando em aumento de produtividade com duas aplicações de tricyclazole ou benomyl na cultivar IAC 202. As perdas quanto ao peso de 100 panículas e produtividade foram 22,3% e 25,1% na IAC 202, e 23,6% e 20,5% na Caiapó, respectivamente, com duas aplicações de tricyclazole. O valor do índice de sustentabilidade para produtividade foi máximo (0,59) com duas aplicações de tricyclazole, seguido por uma aplicação no emborrachamento (0,46) e na emissão de panícula (0,40) na cultivar IAC 202. Houve ausência de resposta das cultivares Rio Paranaíba e Araguaia às aplicações de fungicidas no controle da brusone nas panículas em relação à produtividade.

Efficacy of Fungicides and Bio-Agents against Pyricularia gresia in Paddy and Yield Gap Analysis Thought Frontline Demonstration

“…Various workers observed that the P. fluorocens and T. harzianum all treatment significantly control the neck blast and leaf blast disease (Sueyadi et al, 2013;Hegde, 2006 4 and fig 1). Our results are in conformity with earlier reports by Sood and Kapoor (1997), Tirmali et al, (2001), Prabhu et al, (2003) Debashis et al, (2012), Ganesh et al, (2012) and Prasanna and Veerabhadraswamy (2014) which reported that fungicides application increases the yield of rice.…”

Management of Stem Rot Disease of Paddy Using Fungicides

“…Our results are in conformity with those of previous publication where, fungicides application increases the yield of rice (Sood and Kapoor, 1997;Tirmali et al, 2001;Prabhu et al, 2003, Usman et al, 2009Naik et al, 2012;Bhuvaneshwari and Raju, 2012;Bag et al, 2016;Pramesh et al, 2016 a & b). The increased yield is mainly due to reduced disease severity of stem rot disease of rice.…”

Novel Fungicides for the Management of False Smut Disease of Rice Caused by Ustilaginoidea virens

“…In case of rice, many researchers have reported the increased grain yield after application of fungicides due to reduction in biotic stress on plant during critical growth stages (Sood and Kapoor, 1997;Tirmali et al, 2001;Prabhu et al, 2003;Usman et al, 2009;Naik et al, 2012;Bhuvaneshwari and Raju, 2012;Bag et al, 2016. For management of false smut disease, efficacy of many fungicides has been reported previously (Chen et al, 2013;Kumar, 2015;Raji et al, 2016).…”