Management of Anthracnose in Common Bean by Foliar Sprays of Potassium Silicate, Sodium Molybdate, and Fungicide

Abstract

Management of anthracnose in common bean by foliar sprays of potassium silicate, sodium molybdate, and fungicide. Plant Dis. 98;84-89.This study aimed to determine whether foliar sprays of potassium silicate (KSi), sodium molybdate (NaMo), or a combination of both (KSi + NaMo), with or without the fungicide azoxystrobin (Azox), could reduce anthracnose symptoms and, consequently increase yield. Two two-by-four factorial experiments, consisting of untreated or fungicide treated, as well as sprays of KSi, NaMo, KSi -i-NaMo, and no spray (control), were arranged in a randomized block design with three replications. Treatments were as follows: treatment 1, KSi spray; treatment 2, NaMo spray; treatment 3, KSi + NaMo spray; treatment 4. Azox spray; treatment 5, Azox + KSi spray; treatment 6, Azox -i-NaMo spray, treatment 7, Azox + KSi + NaMo spray; and treatment 8, control (no KSi, NaMo, or Azox). The KSi, NaMo, and Azox treatments were sprayed at the rates of 35 g/liter, 90 g/ha, and 120 g a.i./ha, respectively. The KSi was applied at 20, 27, 40, and 55 days after sowing (das). The NaMo was sprayed only at 27 das whereas the fungicide was sprayed at 27, 40, and 55 das. Plants were inoculated with Colletotrichum lindennithianiim at 23 das. Azox reduced the mean area under disease progress curve (AUDPC) by 63% and mean yield was increased by 150%. Similarly, the mean AUDPC was reduced by 29, 14, and 41% with KSi, NaMo, and KSi + NaMo sprays, respectively, while mean yield increased by 13, 20, and 47%, with KSi, NaMo, or KSi + NaMo sprays, respectively. The variables leaf area index (LAI), leaf area index duration (LAD), healthy leaf area duration (HAD), and radiation intercepted (RI) were not affected by KSi spray. The values for the variables LAI, healthy leaf area index (HLAI), LAD, HAD, RI, intercepted radiation of the healthy leaf area, and healthy leaf area absorption were significantly increased as a result of NaMo spray. The results of the present study support the novel possibility ot' using a foliar spray of KSi in association with NaMo to decrease anthracnose symptoms in bean plants and, consequently, achieve greater yield.Corresponding autbor: F. A. Rodrigues,

Effect of root or foliar application of soluble silicon on plant growth, fruit quality and anthracnose development of capsicum

“…Similarly, the anthracnose disease severity was reduced by Si root supplement in beans with a delay in disease initiation (Polanco et al, 2012). Further, the anthracnose disease of common bean has been reduced by 41% by foliar application of potassium silicate together with sodium molybdate (Polanco et al, 2014).…”

Effects of blast on components of wheat physiology and grain yield as influenced by fungicide treatment and host resistance

“…Because crop yield and dry weight are often more strongly correlated with healthy rather than diseased leaf area, several measures of crop health such as healthy leaf area duration (HAD) and healthy leaf area absorption (HAA) have been proposed for quantifying the effects of plant diseases on crop loss (Waggoner & Berger, ). In addition, given that damage caused by pathogens is known to affect the radiation intercepted (RI) and radiation use efficiency (RUE) (Johnson, ), RI and RUE have also been used as measures of the effects of diseases on crop loss (Bergamin Filho et al ., ; Polanco et al ., ; Moreira et al ., ).…”

<b>Split application of molybdic fertilizer at the reproductive stage of common bean increases the molybdenum content in seed

“…Mo can improve nitrogenase and nitrate reductase activities in the common bean (Pessoa et al, 2001), as both are enzymes linked to nitrogen (N) metabolism of plants. Mo fertilization can also increase the common bean's resistance to diseases (Jesus et al, 2004;Polanco et al, 2014). Thus, yield can be enhanced up to 300% compared with common bean plants that were fertilized neither with Mo nor with an N side dressing (Amane, Vieira, Novais, & Araújo, 1999).…”