Agronomic and Economic Feasibility of Tomato and Lettuce Intercropping in a Soilless System as a Function of the Electrical Conductivity of the Nutrient Solution

Abstract

<jats:p>An intercrop is studied here as a new way of farming in soilless systems within a protected environment. To estimate the efficiency of intercropping in this cultivation system, an experiment was conducted to evaluate the effect of the electrical conductivity (EC) of the nutrient solution (2.0, 2.5, and 3.0 dS·m<jats:sup>−1</jats:sup>) on lettuce and tomato plants and on the agronomic and economic feasibility of the intercrop compared with monoculture. The results indicated that a moderate increase in EC from 2.0 to 3.0 dS·m<jats:sup>−1</jats:sup> did not exert any important effect on tomato plant production or quality but did cause a decrease in lettuce yield in both the first and second crops. Intercropping was only feasible for lettuce when the tomato and lettuce plants were transplanted on the same day. The highest tomato (G class) and lettuce yields were achieved at an EC of 2.5 dS·m<jats:sup>−1</jats:sup>; this condition resulted in the highest intercrop profitability (0.53 €·m<jats:sup>−2</jats:sup> more) when compared with tomato monoculture.</jats:p>

Biostimulant and Elicitor Responses to Cricket Frass (Acheta domesticus) in Tomato (Solanum lycopersicum L.) under Protected Conditions

“…The pH of the nutrient solutions was always maintained at 5.8 with the addition of nitric acid; the amount of nitric acid required always increased nitrate to a negligible extent. New fertigation was applied when the water in the crop unit reached 10% of the easily available water [ 27 , 28 , 29 ].…”

Lettuce in Monoculture or in Intercropping with Tomato Changes the Antioxidant Enzyme Activities, Nutrients and Growth of Lettuce

“…The production of horticultural crops in small farms, normally characterized by the intensive use of renewable and non-renewable resources, is the sector that can most take advantage and benefit from this agronomic practice due to the possibility of the cultivation of two or more species in the same area [11]. Numerous studies have published the beneficial results of intercropping in fields [4,7,8,11,12] and greenhouses [13,14]; on the other hand, there is little information on soilless culture [15]. The efficiency of the intercropping system will depend on the choice of the crops and the management of the cultivation system for minimizing the competition between species for the environmental resources and for maximizing the complementarity between them [12].…”

“…Studies have indicated that the intercropping of tomato (Solanum lycopersicon L.) and lettuce (Lactuca sativa L.) is feasible in both conventional soil [13,14] and soilless culture [15]. In greenhouse conditions, both tomato and lettuce meet the most important criterion and perhaps the first requirement for success in the association: the plants must be complementary in agrobotanical characteristics in order to take advantage of temporal and/or spatial compatibility [13], since they are planted at the same time, reducing competition mainly for light.…”

“…On the other hand, numerous studies have discussed the ability of intercropping systems to increase productivity, but there is little information on the feasibility of such a system in soilless crops [13][14][15] and furthermore on the combined effects of tomato and lettuce intercropping on antioxidant enzyme activities, mineral nutrition and productive characteristics of the secondary crop (lettuce). The objective of this study was to evaluate yield, production parameters, MDA, antioxidant enzyme activity, mineral nutrient content and profitability of tomato under soilless culture intercropping systems, using two different lettuce cvs as secondary crops.…”

Effect of the Matric Potential on Growth and Water, Nitrate and Potassium Absorption of Vegetables under Soilless Culture

“…During the last three decades, coconut coir has become a widely accepted inorganic and organic substrate substitute, both in ornamental and vegetable crops and in herbaceous and even woody crops (Abad et al 2005;Evans and Stamps, 1996;Gallegos et al 2020;Gallegos-Cedillo et al 2018;Meerow 1995;Morales and Urrestarazu 2013;Morales et al 2018;Moya et al 2017;Pozo et al 2015;Stamps and Evans 1997;Urrestarazu et al 2008a;Urrestarazu et al 2016;Nájera and Urrestarazu 2019). Models of (1) cultural management (Cunha-Chiamolera et al 2017), (2) fertigation systems (Urrestarazu et al 2015), and (3) in comparison to inorganic substrates (Pozo et al 2014) have been developed using coir substrates as references.…”