Nutrients content and yield in selected cultivars of leaf lettuce (Lactuca sativa L. var. crispa)

Abstract

Five cultivars of leaf lettuce (Lactuca sativa L. var. crispa) – Bergamo, Dubáček, Frisby, Lollo Rossa and Redin – were evaluated in two-year experiments carried out at the Faculty of Horticulture in Lednice (Mendel University of Agriculture and Forestry in Brno). Experiments were conducted in two trial years, 1998 and 1999; the lettuce was cultivated in three seasons: spring, summer and autumn. After the harvest, contents of following nutrients were evaluated: vitamin C, minerals (K, Na, Ca, Mg), fibre, dry matter and nitrates. The weight of leaf rosette was also recorded. The contents of selected substances and weights of leaf rosette were ranged as follows: vitamin C (65 to 302 mg/kg), potassium (2,394 to 6,477 mg/kg), sodium (39 to 223 mg/kg), calcium (200 to 755 mg/kg), magnesium (110 to 413 mg/kg), fibre (4.98 to 12.22 g/kg), dry matter (59 to 140 g/kg), nitrates (293 to 3,817 mg/kg) and the weight of leaf rosette (164 to 502 g). A significant influence of cultivar was found in the case of K, Na, and Ca content, as well as in dry matter and weight of leaf rosette. The growing season affected significantly all the evaluated substances, except for fibre. The year of cultivation affected all the evaluated parameters but Ca. It appears from the results that the contents of monitored substances were significantly influenced by cultivar as well as by growing season and year.

The Effect of Biostimulant and Fertilizer on “Low Input” Lettuce Production

“…5) and were in the range indicated in literature (Ismail and Fun 2003, Koudela and Petříková 2008, Masamba and Nguyen 2008. Since Bio-algeen S-90 preparation contains amino acids, we expected that this treatment would increase the concentration of N in lettuce leaves; however, this was not the case.…”

The Effect of Plant Growth Promoting Bacteria on Transplants Growth and Lettuce Yield in Organic Production

“…According to Herencia et al (2011) and Kleiber et al (2013), in less favorable conditions during autumn, synthesis of N-poor molecules (e.g., polyphenols, cellulose, starch) may increase dry matter content. A significant correlation between higher dry matter content and increased amount of macro-and micronutrients in lettuce was observed by Fontanetti et al (2001) and Koudela and Petříková (2008). In our study, the strongest accumulation in lettuce leaves was obtained for polyphenols, calcium, and nitrates (Table 2).…”

Cambios en las propiedades fisicoquímicas de cuatro variedades de lechuga (Lactuca sativa L.) durante el almacenamiento

“…Significant differences were found in comparing varieties Lollo Rossa, Graziella and Parris Island to Alpha on day 8; and Lollo Rossa, Parris Island and Alpha to Graziella on day 12, as also reported by Petříková and Pokluda (2003). Vitamin C levels are influenced by weather (temperature, relative humidity and solar radiation), crop management practices and postharvest management, as well as the variety in question (Koudela and Petříková 2008). Although lettuce is not rich in vitamin C, the fact that it is usually consumed fresh allows the complete assimilation of this nutrient and its utilization in several biological processes that -due to the thermolabile nature of this vitamin-would be affected if the product was cooked as other foods (Lee and Kader 2000;Aćamović-Djoković et al 2011).…”