Pilar Mazuela

Vegetable Waste Compost as Substrate for Melon

Abstract The suitability of compost from horticultural residues as a growing medium in vegetable crop production was compared with the popular rock wool and coconut coir waste substrate. Physical and physio-chemical properties were initially characterized to adjust the management of this substrate for horticultural purposes. Leaching experiments were carried out with acid solution and standard nutrient solution. Two experiments were conducted to compare this compost with rock wool and coconut coir waste in terms of yield and fruit quality of a melon crop. The compost was found to initially have high salt content and a high pH. The results suggested that compost seems to be an acceptable growing medium for soilless vegetable production, provided that it is leached prior to use. Once it is leached, the compost is an acceptable substitute for rock wool and coconut coir waste.

Effect of Substrate Reutilization on Yield and Properties of Melon and Tomato Crops

ABSTRACT Certain ecologically-friendly substrates have recently been shown to be perfectly viable alternatives to other more traditional ones such as rockwool, perlite, or some hydroponic systems. However, in order to be competitive for vegetable production in the Mediterranean region, substrates must be used for at least one year. The present study assessed random samples of two commercial substrates, almond shell and compost from greenhouse vegetable residue. The substrates were evaluated as growing media for long-term soilless production. Three experiments were conducted to evaluate the effects of reusing these substrates, comparing them with rockwool in terms of yield and fruit quality characteristics of melon and tomato. The physical, physico-chemical, and chemical properties studied differed significantly on reutilizing these materials. However, these differences did not prove to be limiting factors when fertigation parameters applied were adjusted according to substrate properties. The results suggest that compost and commercial almond shells seem to be acceptable growing media after at least 265 and 530 days of reutilization, respectively.

Effects of Heating Nutrient Solution on Water and Mineral Uptake and Early Yield of Two Cucurbits under Soilless Culture

ABSTRACT Root temperature may affect the production of greenhouse vegetables under soilless culture. Four independent experiments were carried out over two consecutive crop cycles using two different substrates: rockwool and coconut coir waste. Three heating treatments were applied: non heating (T0), nutrient solution at 12–16°C (T1), and at 18–22°C (T2). The experiments were carried out in greenhouses in Almería (SE Spain) on cucumber and melon. Mean substrate and air temperature were not affected by the treatments. Under conditions of nutrient solution heating EC and percentage of drainage volume decreased, while water and mineral nutrient absorption increased. However, results showed great differences between both crops and substrates. A significant decrease in nitrate and phosphate emission from the substrates was also recorded, especially in rockwool substrate. Few effects were observed concerning yield and fruit quality parameters, but in rockwool-grown melon early yield was enhanced. It follows that nutrient solution heating is a low-cost and environmentally friendly method of increasing early melon yield.

The Effect of Amendment of Vegetable Waste Compost Used as Substrate in Soilless Culture on Yield and Quality of Melon Crops

One of the main environmental impacts of forced systems in horticulture — such as plastic covered and soilless culture — is the generation of organic plant residues and substrate waste. Many people are keen on research and development of ecologically friendly substrates. Thus, leaching experiments have been carried out with distilled water to determine whether compost — from horticultural greenhouse crop waste — can be used as growing media in vegetable crop production. The compost was examined and compared to other substrate alternatives like coconut coir waste. Two experiments were conducted in order to compare the two composts with coconut coir waste in terms of yield and fruit quality of melon crops (Cucumis melo). Electrical conductivity decreased sharply with leaching and eventually reached acceptable levels despite the high initial value of this parameter in the composts. This drop in electrical conductivity was parallel to that experienced in the contents of soluble mineral elements, with mainly high levels in SO42−, K+, Cl−, Mg2+, Ca2+ and Na+- concentrations. Most of the soluble mineral elements in compost were removed applying six times the amount of water. The comparison between two environmentally sound substrates, show that compost seems to be an acceptable ecological growing medium and similar to commercial coconut coir in soilless culture, it does not affect yield and quality of melon crops.

PRODUCCIÓN Y CALIDAD DE UN TOMATE CHERRY EN DOS TIPOS DE INVERNADERO EN CULTIVO SIN SUELO

El valle de Azapa, al extremo norte de Chile, posee un clima que le permite producir hortalizas durante todo el ano, concentrando la produccion durante el invierno. El tomate es el cultivo que mas se planta, con una superficie media de 840 hectareas al aire libre. Muchos agricultores estan mejorando los procesos de produccion con malla antiinsectos y una minoria esta trabajando con invernaderos mas sofisticados. El objetivo del proyecto fue evaluar dos tipos de invernadero, para determinar el efecto sobre la produccion y calidad del tomate cherry. Se cultivo en un sistema de cultivo sin suelo, utilizando perlita y compost como sustrato. Los tratamientos fueron: T0: invernadero tipo multitunel de policarbonato (alta tecnologia) y T1: invernadero tipo capilla a un agua cubierto con malla antiinsectos (baja tecnologia). Se cuantifico el efecto del tipo de invernadero sobre los parametros de fertirriego, produccion y la calidad del fruto. En los resultados no se observaron diferencias significativas en la produccion, aunque hubo diferencia en el numero de frutos, siendo mayor bajo malla antiinsecto. Respecto a la calidad, hubo diferencia significativa en calidad de frutos, con un mayor contenido de solidos solubles y porcentaje de materia seca en los tomates cultivados en el invernadero de baja tecnologia. Con los resultados de estos experimentos se puede concluir que la produccion es igual en ambos invernaderos, aunque el tamano del fruto tiende a ser menor cuando se cultiva bajo malla antiafido, con un mayor contenido de solidos solubles y mayor porcentaje de materia seca.

Manejo del cultivo de hortalizas y su efecto en la sustentabilidad de un valle costero del desierto de Atacama, Chile

Los valles costeros de la XV Region presentan condiciones climaticas excepcionales para el cultivo de hortalizas durante todo el ano, siendo el principal proveedor de hortalizas de la zona Central durante el invierno. El alto costo de la tierra en el valle de Azapa y escasa disponibilidad de agua esta obligando a que los productores de hortalizas mejoren su sistema de produccion para mantener esta actividad. El cultivo bajo malla ha mejorado las condiciones fitosanitarias, lo que ha impactado positivamente la produccion. El objetivo de este trabajo fue describir dos procesos de produccion en el cultivo de tomate (aire libre y sistema protegido con malla) y pimiento (bajo malla) y sus efectos en la produccion, eficiencia en el uso del agua y la concentracion de sales que emite al medioambiente. Los resultados indican que los sistemas protegidos mejoran la eficiencia en el uso del agua y disminuyen la emision de nutrientes al medioambiente por kg producido y se sugiere que, con nuevas tecnicas de cultivo, es posible mejorar considerablemente la eficiencia en el uso de los recursos sin afectar la produccion.

Vegetable Waste Compost Used as Substrate in Soilless Culture

One of the main environmental impacts of forced systems in horticulture – such as plastic covers and soilless culture is the generation of organic plant residues and substrate waste. For example, the surface area of greenhouse cultivated crops in the province of Almeria, in southeastern Spain, exceeds 30,000 ha. These generate approximately 1,000,000 tons of solid plant waste per year. Greenhouse industry residues cause serious environmental and visual pollution, making it necessary to look for new ways to eliminate these plant residues. This mass not only acts as a host for pests, microorganisms, rats and insects; it also has other harmful environmental effects such as pollution of the soil by toxic elements, effluent runoff, and the emission of bad smells. Conway (1996) indicated that an important factor for sustainable agriculture in areas using protected systems is the need to eliminate the harvest residues of these crops. Controlled composting appears to be an effective method of eliminating residues by recycling them. For example, Ozores-Hampton et al. (1999) reported that in Florida 1.5 million tons of compost could be produced per year. The wastes generateed by intensive agriculture systems are very varied and frequently cannot be reused directly. Cara and Ribera (1998) indicated that greenhouses generate 29.1 tons of vegetable waste per ha and 6-10 tons of substrate remains per year in the province of Almeria (Spain). A less indiscriminate form of management of these residues, however, could turn them into usable products. This would also reduce their environmental impact. Callejon et al., 2010 indicated that the assessment of the environmental impact of a potential waste treatment plants showed that it would be better to recycle and compost waste than to try to obtain energy from it through combustion. This compost can be used as a soil conditioner or to improve the structure in degraded soils or those with low organic matter content. Another alternative is to reuse these residues, incorporating them as ecologically friendly substrates in soilless cultivation in the form of compost. Using waste materials, most of them locally produced, as soilless growing media has been the subject of an important number of studies, especially as an alternative to peat for ornamental potted plants (e.g., Ingelmo et al., 1997; Offord et al., 1998; Lao and Jimenez, 2004a,b), and less frequently for vegetable production (Shinohara et al., 1999; Ball et al., 2000) and even for tomato transplant production (Ozores-Hampton et al., 1999). However, it

Propagación vegetativa de Lisianthus (Eustoma grandiflorum RAF) cv. Abc 2-3 Blue Rim

espanolEl creciente interes por el cultivo de Lisianthus y la falta de datos experimentales disponibles demanda el estudio del comportamiento fenologico y productivo de esta especie. Uno de los principales aspectos que preocupa al productor de flores es el manejo agronomico y la obtencion de plantas de este cultivo. El objetivo de este trabajo fue establecer dos experimentos para evaluar la tecnica de propagacion y su efecto en el enraizamiento de esquejes bajo distintas concentraciones de auxinas. El material vegetal fue extraido de plantas madre una vez realizado el raleo y pinzamiento de las varas para dejar las mas vigorosas. En el primer experimento se utilizo una mesa cerrada (MC), cubierta con polietileno transparente, regada en sustrato hasta saturacion. En el segundo experimento se utilizo una mesa bajo nebulizacion (MBN) con boquillas atomizadoras para el riego. El diseno fue de bloques completos al azar y para separacion de medias se uso el test de Duncan. Los tratamientos fueron segun concentracion de acido indolbutirico (AIB): T0, testigo, sin AIB; T1, 250 ppm AIB; T2, 500 ppm AIB y T3, 1.000 ppm AIB. Los resultados indican que el experimento en MC la aplicacion de auxina mejora el enraizamiento de esquejes, sin que se observe diferencia significativa entre tratamientos. En el segundo experimento MBN, se observa que en la aplicacion de AIB mejora la propagacion, obteniendose mejores resultados con la mayor concentracion de auxina. EnglishThe growing interest in Lisianthus cultivation and the lack of available experimental data demands the study of the phenological and productive behavior of this species. One of the main concerns of the flower producer is the agronomic management and obtaining plants of this crop. The objective of this study was to evaluate the propagation technique and its effect on rooting of cuttings with different auxin concentrations. The plant material was extracted from donor plants which were thinned and topped to make them more vigorous. The first experiment used a closed system (CS) covered with transparent polyethylene, irrigating the substrate to saturation. The second experiment used a table with fogging system, with spray nozzles for irrigation. The design was randomized complete blocks; the Duncan test was used to analyze differences between means. The treatments were different concentrations of indole butyric acid (IBA): T0, control without IBA; T1, 250 ppm IBA; T2, 500ppm IBA and T3, 1000ppm IBA. The results of the CE experiment indicated that auxin application improved the rooting of cuttings, but there were no differences between treatments. In the TWF experiment the application of IBA improved the propagation; better results were produced by higher concentrations of the auxin.

Tenencia de tierra y aguas de pequeños y medianos agricultores del valle de Azapa, Arica, Chile

espanolEl valle de Azapa, uno de los valles costeros de la XV Region de Arica y Parinacota, en el extremo norte de Chile, presenta condiciones climaticas excepcionales para el cultivo de hortalizas durante todo el ano, siendo el principal proveedor de hortalizas de la zona central durante el invierno. El alto costo de la tierra y escasa disponibilidad de agua ha incentivado las mejoras tecnologicas en los procesos de produccion para mantener esta actividad sustentable en el tiempo. El objetivo de este trabajo fue describir la tenencia de tierra por tamano de explotacion y el numero de acciones de agua asociados a la explotacion de pequenos y medianos agricultores del valle de Azapa. Para ello se realizo una encuesta en una muestra correspondiente al 5% de los agricultores del valle de Azapa. Los resultados indican que el 27% de los agricultores encuestados tiene menos de una accion de agua por ha; 35% tiene mas de una accion de agua por ha y el 38% tiene una accion de agua por ha. EnglishAzapa is one of the coastal valleys of Arica and Parinacota region, in the extreme north of Chile, that presents exceptional climatic conditions for the cultivation of vegetables off season, being the main supplier of vegetables in the Central area during the winter. The high cost of land and little water availability has encouraged technological improvements in production processes to maintain this sustainable activity over time. The aim of this study was to describe the land tenure by farm size and the number of shares of water associated with the exploitation of small and medium farmers in Azapa Valley. For this, a survey was conducted on a sample corresponding to the 5% of farmers of Azapa valley. The results indicate that 27% of farmers surveyed have less of an action of water per hectare; 35% have more than one share of water per hectare and 38% have an action of water per hectare.

Antecedentes generales para la sustentabilidad de la producción hortícola en el valle de Azapa, Arica, Chile

The region of Arica and Parinacota has exceptional conditions for growing vegetables off season, being the main supplier of vegetables for the country during the winter. Average regional production is significantly major than the national average, with a high commercial value that makes horticulture of Azapa´s Valley a very competitive activity. The main advantages for growing vegetables are the natural conditions of soil, climate and water. The main problems are related to crop management, especially irrigation techniques, pest and disease control and soil fertilization of the crop. This situation was described about 40 years ago and observed until today