Survival of pantoea ananatis, causal agent of maize white spot disease in crop debris

The objective of this work was to show which traits are influenced by the interaction genotype x irrigated environment, to reveal trends of linear associations in each environment and to identify genotypic variation through canonical variable analysis in maize. The experiment was conducted in Campos Borges – RS. The experimental design used was randomized blocks organized in a factorial scheme, being two cultivation environment (dry environment characterized only by the availability of rainwater; irrigated environment where a 15 mm layer of water was applied ten days apart the crop cycle, from seedling emergence to physiological maturity stage) x 13 hybrids of maize, arranged in three replicates. The traits plant height, insertion of ear height, mass of one thousand grains and grains yield are influenced by the genotypes x environments interaction. The irrigated environment presents superiority in relation to dry environment for all the traits studied. In general, the genotype G9 performs better than others. The irrigated environment presents superiority than dry environment, in relation to the traits plant height, insertion of ear height, mass of one thousand grains, grain yield per hectare, ear length, ear diameter, ear mass, grains mass per ear and number of grains per ear row.

Section: Introductionmentioning

confidence: 99%

Cultivation of maize in different environments and their effects on agronomic traits

Carvalho

Eickhoff

Silva

et al. 2021

“…Depending of the host and ecological niche, P. ananatis strains may be mutualists, saprophytes or pathogenics. It was described as epiphytic on leaves of healthy maize plants by Bomfeti et al (2008) and on maize crop debris by Sauer et al (2015). Our results showed that P. ananatis can be isolated from health maize leaves surface at different stages (10, 12 and 16 leaves).…”

Section: Distribution Of P Ananatis In Maize Plantsmentioning

confidence: 63%

Viability and dissemination of Pantoea ananatis, etiological agent of Maize White Spot disease

Escanferla

Wysmierski

Meirelles

et al. 2018

Maize white spot (MWS) is a disease widely spread in maize production regions in Brazil and causes serious economic damages to the culture. Little is known about the dissemination, growth and development conditions of the MWS causal agent, the bacterium Pantoea ananatis. The objective of this work was to determine the viability of this bacterium, as well as its distribution in the plant. P. ananatis after isolated was stored in both, Nutrient Broth (NB) medium and in mineral oil. For the viability tests, the cultures stored in NB were maintained at 12ºC and –6ºC and the cultures stored in mineral oil were maintained at room temperature. The isolate remained viable for seven months in NB medium at the two temperatures assessed, and four months when stored in mineral oil. The presence of the P. ananatis bacteria was analyzed in, 1) soil samples collected close to rhizosphere, 2) in seeds from plants severely attacked by MWS, 3) foliar segments of healthy plants and 4) the stem of healthy plants. P. ananatis was found surviving epiphytically on the leaf surface and its population increased with plant age, air relative humidity, and decreasing of temperature. This agent was not found neither rhizosphere nor in seeds, but it was isolated in low quantity in maize stem. P. ananatis resides epiphytically on leaves and, due to several factors, may trigger injuries to its host. All epiphytic isolates were characterized in regards to ice nucleation activity, a characteristic of this pathogen.

“…National production of the grain in the 2017/18 crop showed an average yield of more than 5.5 t ha -1 (Companhia Nacional de Abastecimento [CONAB], 2018), mainly due to the use of a high technological level regarding the use of hybrids and intensive crop management. However, national productivity is still below the potential productivity, that can reach 16 to 18 t ha -1 (Sangoi et al, 2011;Sauer, et al, 2015;Santos, Bizzarri, Barbosa, & Zucareli, 2017;Escanferla, Wysmierski, Meirelles, & Paccola-Meirelles, 2018;Rosa et al, 2019).…”

Section: Introductionmentioning

confidence: 99%

Efficiency in nitrogen management using conventional and transgenic technology in the cultivation of maize

Carvalho

Peter

Demari

et al. 2021

The objective to evaluate the maize yield components as a function of the top-dressing nitrogen partitioning in maize plants with conventional and transgenic technology. The experiment was carried out in the agricultural crops of 2012/2013 and 2013/2014, in the municipality of Tenente Portela-RS, Brazil. The experiment was set up in a randomized block design in a factorial scheme with two genetic technologies x 11 nitrogen fertilization treatments, arranged in three replications. The treatments were composed of top-dressing applications in the phenological stages V2 - two fully expanded leaves, (V2), V4 - four fully expanded leaves, (V4), V6 - six fully expanded leaves (V6) and V8 - with eight fully expanded leaves (V8) and split applications in V2+V4; V2+V6; V2+V8; V4+V6; V4+V8; V6+V8; and V2+V4+V6+V8. There was interaction between genetic technologies and levels of nitrogen fertilization in the maize crop. The highest grain yield was obtained with conventional technology because it presented plants with greater prolificacy, ear diameter and number of grains per row. Grain yield was superior with nitrogen fertilization in V4 and in nitrogen splitting in the V4 + V6, V4 + V8 and V2 + V4 + V6 + V8 stages.