New Technique to Create a Suspension Containing Bacteriophages and How It Can Be Used to Control Cabbage Leaf Spot Caused by <i>Xanthomonas campestris</i> PV. <i>campestris</i>

Abstract

The purpose of the present study was to develop a new method for producing and identifying a bacteriophage suspension and research its potential against plant bacteria. The suspension obtained with the new technique was effective in controlling Xanthomonas campestris PV. campestris both in vitro and in vivo. A difference was observed between the suspension with pathogen (PLP) and crude suspension with lesioned plant without the pathogen originated from it (PLN). Clear zones were observed at 48 h/28˚C in both (PLS) suspension added saccharose and (PLP). Although PLP and PLS treatments showed no statistical difference in CFU values (5 × 10 5 and 1 × 10 5 , respectively), they differed from the crude suspension (PLN) and the control. Then, in vivo assessment of suspensions with clear zones in the dishes was performed. In vivo (PLPS) and (PLPP) treatments consisting of inoculum were added to the crude suspensions (PLS and PLP) to increase bacteriophages. A decrease in the disease severity index compared to the control was observed, showing that treatment with the phage suspension protects the plant. The lowest disease indexes were reported with (PLP) and (PLS), with values of 1.46 and 1.40, respectively. The highest averages in dry matter (5.1 in both treatments) were obtained with (PLP) and (PLS) treatments.

Intellectual Capital as a Generator of Innovation in Companies: A Systematic Review

“…The capacity of a company to generate innovation related to intellectual capital or its ability to use its knowledge resources (Subramaniam and Youndt, 2005). In this way, the terms knowledge, intellectual capital, and innovation are highly related, as shown by several studies that characterize innovative companies as companies that create knowledge (for example, Nonaka and Takeuchi, 1995) other studies emphasize that new products result from incorporating the knowledge of the organization (for example, Stewart, 1997) and others describe innovation as a knowledge management process (for example, "Madhavan and Grover, 1998").…”

“…With this table, it was possible to establish that the term intellectual capital emerged in the early nineties of the twentieth century in the United States and Sweden, mainly, and that measures the value of a knowledge of the company in its different areas: people (human intelligence), the organization (the company's know-how, patents, and brands) and the market (satisfaction of a client portfolio). The origin of the term intellectual capital is distinguished from three main areas: the one that arises from the knowledge management as part of the tacit resources (Dierickx and Cool, 1989 (cited in Alizadeh, 2012); Stewart, 1997;Hall, 1992;Klein and Prusak, 1994;Nonaka and Takeuchi, 1995;Sveiby, 1997;Klein, 1998;Ulrich, 1998;Edvinsson and Malone, 1998), that of the accounting-financial sphere, as an indispensable item in the financial statements (Brooking, 1997;Roos et al, 1997;Edvinsson and Malone, 1998;Seetharaman, 2002(cited in Alizadeh, 2012, and a more recent vision that takes up the origin of knowledge aimed at the competitive advantages contribution (Youndt, Subramaniam and Snell, 2004;Chen, Cheng and Hwang, 2005;Viedma, 2007).…”

Using antagonistic soil bacteria and their cell‐free filtrates to control the black rot pathogen Xanthomonas campestris pv. campestris

“…The main strategy used in the black rot combat is the prevention of disease by use of propagation material with good quality. Another way of control widely used is the removal and destruction of diseased plants or part of them, which causes considerable losses in productivity (Marroni and Germani, ). Chemical methods such as fungicides with bactericidal action and antibiotics for agricultural use are also recommended for black rot control (Mello, Silveira, Viana, Guerra, & Mariano, ).…”

“…In general, these bacteria cause damage to the leaf tissue of the host plant, affecting the leaves and the limb. Some of these symptoms are typical, such as the presence V‐shaped lesion; darkening of the veins; and appearance of veins in the petiole and stem, resulting in wilting and necrosis of leaf tissue (Marroni & Germani, ). The disease control can be carried out by cultivation of plant varieties resistant to black rot, or by the control of insect vectors, the elimination of infected plants and the use of healthy seeds (Liu, Garrett, Fadamiro, & Kloepper, ; Tebaldi, Panizzi, & Sader, ).…”

“…One strategy to overcome this has been the search for the micro‐organisms that can either be used as biocontrol agents or produce molecules with antimicrobial activity. Isolation of bacteria from suppressive soil is a good strategy as these organisms have natural biocontrol capacity (Bettiol & Morandi, ; Kinkel, Bakker, & Schlatter, ; Marroni & Germani, ). A microbial sampling of this soil can enable the discovery of micro‐organisms capable of producing substances that can act against important plant pathogens (Bonilla et al., ).…”