The influence of timing the application of nitrogen fertilizer on early blight (Alternaria solani)

Abstract

BACKGROUND Field experiments were carried out in 2016 and 2017 to study the influence of timing the application of nitrogen fertilizer (N‐fertilizer) on the susceptibility of potatoes to early blight. We hypothesized that potatoes that receive N‐fertilizer as split applications or a one‐time application at emergence will have a higher N content and be less susceptible to early blight than those that receive N‐fertilizer as a one‐time application before planting. N‐fertilizer was applied either as a one‐time application before planting or at emergence and as split applications. RESULTS Potatoes that did not receive N‐fertilizer were more susceptible to early blight [high area under the disease progress curve (AUDPC)] than those that did receive N‐fertilizer (low AUDPC). The timing of N‐fertilizer application had a significant effect on the susceptibility of potatoes to early blight. Potatoes that received the entire quantity of N‐fertilizer at emergence or as split applications had higher N contents and were less susceptible to early blight than those that received the entire quantity of N‐fertilizer before planting. Potatoes that did not receive N‐fertilizer had a markedly lower starch yield than potatoes that received N‐fertilizer. Potatoes that received the entire quantity of N‐fertilizer before planting had a lower starch yield than potatoes that received the entire quantity of N‐fertilizer at emergence or as split applications. CONCLUSION N‐fertilizer applied as a one‐time application at emergence or as a split application was the best treatment to ensure both high N content and lower attack of early blight, which confirms our hypothesis. © 2018 Society of Chemical Industry

The role of abiotic and anthropogenic factors in the development of Alternaria leaf spot on potato plantings in the North-West of Russia

“…According to the results of the studies, it was revealed that with an increase in mineral nutrition, there was a decrease in the level of development of Alternaria on potato plants. This regularity found statistical confirmation in both studied cultivars, and it fully agrees with the published data, from which it is known about the positive effect of nitrogen and organic fertilizers on the resistance of potato plantings to Alternaria [14][15][16]. The increase in resistance under the influence of fertilizers is due to a decrease in the permeability of cell membranes, an increase in the osmotic pressure of the cell sap, the content of dry substances and reducing sugars in it, which creates unfavorable conditions for the spread of the pathogen in plant tissues [8].…”

Review: Holistic pest management against early blight disease towards sustainable agriculture

“…First and foremost, crop rotation is an essential practice to minimize the possibility of the onset of EB infection, given that continuous potato production in the same field over 2–3 years is risky 98 . Two years without potatoes is the minimum interval to delay the onset of EB in the potato field 99 . Rotation is an efficient practice not only for reducing pests and diseases but also for balancing soil nutrients, thus effectively improving the physical and chemical properties of soil and regulating soil fertility.…”

“… 98 Two years without potatoes is the minimum interval to delay the onset of EB in the potato field. 99 Rotation is an efficient practice not only for reducing pests and diseases but also for balancing soil nutrients, thus effectively improving the physical and chemical properties of soil and regulating soil fertility. However, there exist a couple of pitfalls in the practice: (i) the production schedule needs to be changed every year to increase land utilization and (ii) there is a possible reduction in economic return over several years due to less potato production, which is valuable as a cash crop for farmers.…”

Bokashi, Boiled Manure and Penergetic Applications Increased Agronomic Production Variables and May Enhance Powdery Mildew Severity of Organic Tomato Plants

“…For powdery mildew, in general, higher soil nitrogen availability leads to increase and those disease infections [15]. However, on potato (Solanum tuberosum L.), experiments showed that no application of nitrogen led to higher attack of A. solani [16]. Nitrogen source also affects plant metabolism, changing susceptibility to a pathogen [17][18][19].…”