ABSTRACT Greenhouse experiments and productions require a high-level control of pests and diseases. Nowadays, society demands to find sustainable alternatives to replace agrochemicals in food production. Solarization is one of the most promising tools due to its low installation cost and control efflciency. The objective of this study was to evaluate the effect of solarization on a substrate for a greenhouse experiment in Córdoba, Argentina. At the INTA-Manfredi Agricultural Experimental Station, 12 m3 of substrate underwent the solarization process, being exposed to solar radiation for six months (December 2021-May 2022). In addition, substrate control remained in natural conditions. Soil functional groups using different growth culture media were measured to verify the solarization effect. The solarized substrate showed a reduction in proteolytic microorganisms (90 %), mesophiles (93 %) and fungi (100 %). The ammonifiers and biological nitrogen fixers microorganisms were reduced by 78 % compared to the control treatment, while yeasts and Bacillus spp. showed reductions up to 64 % and 69 %, respectively. Solarization achieved a 99 % reduction of weeds. The pH decreased by 1.9 % and the electrical conductivity (EC) increased by 5.91 % in the solarized substrate. The total dissolved solids increased by 169 % for the solarized substrate.

RESUMEN Los ensayos y la producción en invernaderos requieren un alto nivel de control de plagas y enfermedades. La sociedad exige alternativas sostenibles que sustituyan a los agroquímicos. La solarización es una de las herramientas prometedoras debido a su bajo costo y eficiencia de control, para la desinfección de sustratos. El objetivo de este estudio fue evaluar el efecto de la solarización sobre un sustrato en Córdoba, Argentina. En la Estación Experimental Agropecuaria INTA-Manfredi, 12 m3 de sustrato se expusieron a la radiación solar durante seis meses (diciembre 2021 - mayo 2022). El sustrato control no fue solarizado. Se midieron grupos funcionales utilizando diferentes medios de cultivo. El sustrato solarizado mostró una reducción de microorganismos proteolíticos (90 %), mesófilos (93 %) y hongos (100 %). Los microorganismos amonificadores y fijadores biológicos de nitrógeno se redujeron en un 78 % en comparación con el tratamiento de control, mientras que las levaduras y Bacillus spp. mostraron reducciones de hasta el 64 % y el 69 %, respectivamente. Las malezas se redujeron 99 %. El pH disminuyó un 1,9 % y la conductividad eléctrica (CE) aumentó un 5,91 % en el sustrato solarizado. Los sólidos disueltos totales (SDT) aumentaron un 169 %.

Abstract Background: Thermal weed control is a viable, cost-effective, and eco-friendly emerging alternative to highly challenged and unsustainable chemical weed control. Objective: To find out the most suitable pre-sowing soil solarization durations for effective weed control and soil fertility enhancement in sesame crop. Methods: A field study was conducted during the summer season of 2016 and 2017. Different soil solarization treatments were applied, including 0, 3, 6, 9, and 12 weeks before sowing (WBS) of sesame by spreading transparent polythene sheets. Results: The temperatures of solarized soil at 10 cm depth were 8-10 oC more than the control. The soil NPK and organic matter contents were gradually increased with increasing solarization durations. The highest soil nitrogen (0.71%), phosphorus (9.63 ppm), K (166.2 ppm), and organic matter content (1.12%) were observed with the longest soil solarization for 12 WBS. Different solarization durations provided 23 to 64% weed control efficiency and up to a 34% rise in sesame yield. Conclusions: Based on the current findings, soil solarization for 12 WBS by polythene sheets is an effective alternative to the chemical weed control method with additional positive effects on soil fertility and sesame yield.

RESUMO Objetivou-se avaliar o efeito da combinação das técnicas de solarização, biofumigação com cama de frango e enxertia na incidência da murcha bacteriana e na produtividade do tomateiro híbrido Absoluto. Foram realizados dois experimentos, em casa de vegetação tipo capela e em campo, no ano agrícola 2013/2014, em propriedade agrícola no município de Barra do Rio Azul-RS. Nos dois ambientes de cultivo, os tratamentos foram organizados em delineamento experimental de blocos casualizados, com as parcelas subdivididas no espaço e os tratamentos dispostos aleatoriamente, em área naturalmente infestada com Ralstonia solanacearum raça 1, biovar 1, filotipo II. Os tratamentos nas parcelas foram solo com solarização, biofumigação, solarização + biofumigação e testemunha; nas subparcelas, foi usado o tomateiro híbrido comercial Absoluto com e sem enxertia sobre o porta-enxerto híbrido comercial Guardião. Com base na incidência da murcha bacteriana, estimou-se o índice de sanidade e a área abaixo da curva de progresso da doença. Avaliou-se também o número, a produção e a massa média de frutos comerciais. Foi constatado efeito benéfico da solarização do solo associada à biofumigação no controle da murcha bacteriana e aumento da produtividade. A enxertia foi mais eficiente no aumento do índice de sanidade e redução da área abaixo da curva de progresso da doença que a solarização e biofumigação, indicando que a associação dos tratamentos é eficaz no controle da doença.

ABSTRACT Considering the aforementioned information, the objective was to evaluate the influence of combining techniques of solarization, biofumigation with chicken manure and grafting on the incidence of bacterial wilt and productivity of the hybrid tomato ‘Absoluto’. Two experiments were carried out in a chapel-type greenhouse and in field, in the agricultural year 2013/2014, in a commercial farm on the municipality of Barra do Rio Azul-RS. In the two cultivation environments, treatments were arranged in randomized block experimental design, with the plots subdivided into space and treatments randomly arranged, in an area naturally infested with race 1, biovar 1, phylotype II of R. solanacearum. The treatments were soil solarization, biofumigation, biofumigation +solarization and control, and in the subplots, the commercial hybrid tomato Absoluto with and without grafting on the hybrid rootstock Guardião. Based on the incidence of bacterial wilt, the plant health index and the area under the disease progress curve were estimated. The number, production and average mass of commercial fruits were evaluated. A beneficial effect was found of soil solarization associated with the addition of chicken manure in the control of bacterial wilt and increase of productivity. Grafting was more efficient in increasing plant health index and reducing the area under the disease progress curve than solarization and biofumigation, thus indicating that the association of the three measures is beneficial to the integrated control of the disease

ABSTRACT In the Gran La Plata region, around 4,600 ha of agricultural crops are grown undercover on Typic Hapludert and Vertic Argiudol soils, characterized by poor drainage because of their high content of expandable clay. The characteristics of the soils, together with the quality of irrigation water and intensive management lead to physical, chemical and biological degradation associated with the presence of abundant pathogens (diseases and nematodes). Therefore, it is one of the most important challenges to find alternatives for soil disinfection that can be adapted to this type of production system, prevent contamination or degradation of resources, and promote soil improvement. This study evaluated the effect of different soil disinfection treatments on the soil properties (pH, EC, MO, RAS, Ca, Mg) and crop yield. The treatments tested were: solarization, biosolarization with chicken manure (50 t ha-1), biosolarization with mushroom residues (100 t ha-1), biosolarization with cabbage residues (80 t ha-1), chemical disinfection and a control. The experiment was conducted during two seasons (2014 and 2015) of a tomato crop. It was observed that biosolarization with chicken manure and mushroom residues increased salinity levels and concentrations of Ca2+ and Mg2*, without a significant improvement in OM levels. Biosolarization with cabbage residues did not affect the soil variables. Solarization and chemical disinfection treatments behaved similarly to the control. Regarding crop yield, chemical disinfection presented the highest values. No significant differences (P < 0.05) were found between the rest of the treatments.

RESUMEN En la región del Gran La Plata se produce bajo cubierta alrededor de 4.600 ha de cultivos agrícolas, sobre suelos Typic Hapludert y Vertió Argiudol, caracterizados por un drenaje deficiente, que junto a la calidad del agua de riego y al manejo intensivo, conducen a degradaciones físicas, químicas y biológicas, que se vinculan con una elevada carga de patógenos (enfermedades y nematodos). Por lo tanto, uno de los desafíos más importantes es encontrar alternativas de desinfección de suelo que se adapten al sistema productivo, que no contaminen ni degraden los recursos, y que promuevan una mejora de los suelos. En el presente trabajo se evaluó el efecto de diferentes tratamientos de desinfección en las propiedades edáficas (pH, CE, MO, RAS, Ca, Mg) y en el rendimiento de un cultivo. Los tratamientos evaluados fueron: solarización, biosolarización con cama de pollo (50 t ha-1), biosolarización con cama de champiñón (100 t ha-1), biosolarización con repollo (80 t ha-1), desinfección química y un testigo, en dos temporadas (2014 y 2015) de un cultivo de tomate. Se observó que la biosolarización con cama de pollo y de champiñón aumentó los niveles de salinidad y las concentraciones de Ca2+ y Mg2*, sin una mejora significativa en los niveles de MO. La biosolarización con repollo no incidió en las variables del suelo. Los tratamientos de solarización y desinfección química se comportaron en forma similar al testigo. Respecto al rendimiento del cultivo la desinfección química presentó los mayores valores. El resto de los tratamientos no se diferenciaron significativamente (P < 0,05) entre sí.

RESUMO Manejos mais eficientes de plantas daninhas podem ser alcançados com diferentes estratégias, visto que a população dessas plantas é modificada de acordo com o sistema utilizado. Objetivou-se avaliar métodos de solarização associados a diferentes coberturas vegetais para o controle de plantas daninhas na cultura do feijão-caupi. Os métodos utilizados foram solarização do solo, com plástico e com coletor solar, associados às coberturas vegetais mamona, crotalária e vegetação espontânea. A fitossociologia das plantas daninhas foi calculada pela frequência, densidade e abundância. As famílias mais infestantes foram Asteraceae, Poaceae e Amaranthaceae. A espécie de maior frequência, densidade e abundância nos tratamentos sem cobertura de solo foi Cyperus rotundus, enquanto Bidens spp. ocorreu apenas em solo não solarizado e sem cobertura. O maior número de plantas daninhas foi encontrado nos tratamentos sem cobertura morta em solo sem solarização ou solarizado com plástico, o qual foi menos eficiente que o coletor solar. A cobertura morta inibe a infestação de plantas daninhas na cultura de feijão-caupi, independentemente da solarização do solo. Contudo, a cobertura com crotalária é mais eficiente na solarização com o plástico que com o coletor solar.

ABSTRACT More efficient weed control managements can be achieved through different strategies, given that the population of these plants changes according to the system used. This study aimed at assessing solarization methods associated with different mulches for weed control in the cowpea crop. The methods used were soil solarization, with plastic sheeting and with solar collector, associated with the following mulches: castor bean, rattlepod and spontaneous vegetation. Weed phytosociology was calculated by frequency, density and abundance. The most infesting families were Asteraceae, Poaceae and Amaranthaceae. The species with the highest frequency, density and abundance in the treatments without mulching was Cyperus rotundus, while Bidens spp. occurred only in non-solarized soil and without mulching. The largest number of weeds was found in the treatments without mulching in non-solarized soil or soil solarized with plastic sheeting, the latter being less efficient than the solar collector. Mulching inhibits the weed infestation in cowpea crops, irrespective of soil solarization. However, rattlepod as mulch is more efficient in the solarization with plastic sheeting than with a solar collector.

Abstract The objective of the present work was to evaluate the effectiveness of control of Meloidogyne spp., through the use of physical, chemical and natural alternatives, physics with solarization, chemistry with the nematode Vidate and the natural one by means of the interspersed plantation of cempasuchil (Tagetes erecta) between tomato plants, as well as the combination between the alternatives used. The experiment was carried out in a commercial greenhouse, located in the community of Chaparrosa, municipality of Villa de Cos, Zacatecas, in 2012. An experimental design was used in complete blocks at random with four repetitions and experimental units of a plant. Water, fertilizer and other agrochemicals were applied by drip, with the handling that the producer normally does. Twelve variables were measured, result of count of nematodes, bunches and fruit weight in different dates. The analysis of variance detected significant statistical differences in seven of the variables; with the results and the correlation analysis that was performed among the variables, it was concluded that, with the inclusion of a cempasuchil plant interspersed between tomato plants, as well as this combined treatment with solarization, the lowest number of nematodes and the greater yield of fruits.

Resumen El objetivo del presente trabajo fue evaluar la efectividad de control de Meloidogyne spp., mediante la utilización de alternativas física, química y natural, la física con solarización, la química con el nematicida Vidate y la natural mediante la plantación intercalada de cempasúchil (Tagetes erecta) entre plantas de tomate, así como la combinación entre las alternativas empleadas. El experimento se llevó a cabo en un invernadero comercial, ubicado en la comunidad de Chaparrosa, municipio de Villa de Cos, Zacatecas, en el año 2012. Se usó un diseño experimental en bloques completos al azar con cuatro repeticiones y unidades experimentales de una planta. Se aplicó agua, fertilizante y otros agroquímicos mediante goteo, con el manejo que el productor hace normalmente. Se midieron 12 variables, resultado de conteo de nematodos, racimos y peso de fruto en diferentes fechas. El análisis de varianza detectó diferencias estadísticas significativas en siete de las variables; con los resultados y el análisis de correlación que se realizó entre las variables, se concluyó que, con la inclusión de una planta de cempasúchil intercalada entre plantas de tomate, así como este tratamiento combinado con la solarización, se obtuvo el menor número de nematodos y el mayor rendimiento de frutos.

RESUMO: A doença de Petri é complexa, ataca plantas jovens de videira e é difícil de ser controlada. O fungo Phaeomoniella chlamydospora é o principal agente causal dessa doença. Os objetivos deste estudo foram: avaliar o local prevalente dos fungos da doença de Petri, em diferentes partes de plantas de videira; avaliar a suscetibilidade de porta-enxertos de videira para o fungo P. chlamydospora; avaliar o efeito da solarização e da biofumigação seguido de tratamento com água quente sobre a desinfecção de estacas do porta-enxerto IAC 766 infectadas com o fungo P. chlamydospora; avaliar o efeito da solarização e da biofumigação seguido de tratamento com água quente sobre o enraizamento de estacas do porta-enxerto IAC 766. Para o teste de colonização, as espécies de fungos detectadas e identificadas em Niagara Rosada enxertada em dois porta-enxertos diferentes foram P. chlamydospora e Phialemoniopsis ocularis. Este é o primeiro relato de P. ocularis em parrerais jovens de videira no Brasil. Ambos os fungos, em particular P. chlamydospora, colonizaram somente a parte basal das plantas, destacando-se os porta-enxertos como foco para medidas de controle. Medidas das estrias escuras no sistema vascular revelaram que Golia foi o porta-enxerto menos suscetível, e o IAC 572 foi o mais suscetíveis para P. chlamydospora. Além disso, a biofumigação ou a temperatura de 37ºC aplicadas por 7 e 14 dias seguidas de tratamento com água quente eliminaram P. chlamydospora em estacas do porta-enxerto IAC 766 sem afetar o enraizamento. No entanto, novos estudos são necessários ainda para validar a eficiência dessas técnicas de desinfecção.

ABSTRACT: Petri disease is complex, attacks young vine plants and it is difficult to be controlled. The fungus Phaeomoniella chlamydospora (Phc) has been identified as the main causative agent of this disease. This study aimed to evaluate the prevalent colonization of the Petri disease fungi in different portions of vine plants; to assess the susceptibility of grapevine rootstocks to the fungus P. chlamydospora; to assess the effect of solarization and biofumigation, followed by hot-water treatment (HWT), on the disinfection of cuttings of the rootstock IAC 766 infected with P. chlamydospora, and assess the effect of solarization and biofumigation, followed by HWT, on the rooting of cuttings of the rootstock IAC 766. For the prevalent colonization test, the fungus species detected and identified in ‘Niagara Rosada’ grafted on two rootstocks different were Phc and Phialemoniopsis ocularis. This is the first report of P. ocularis in a young vineyard in Brazil. Both fungi, in particular Phc, colonized only the plant’s basal part, drawing attention to the rootstock as target for control measures. Measurement of the dark streaks in the vascular system revealed that Golia was the least susceptible rootstock, and IAC 572 was the most susceptible to Phc. Moreover, biofumigation or temperature of 37°C applied for 7 and 14 days, both followed by HWT, suppressed Phc in cuttings of the rootstock IAC 766 without hampering their rooting. Meanwhile, new studies are needed to validate the efficiency of these disinfection techniques.

ABSTRACT The use of non-polluting control measures has increased in recent years, allowing reducing the application of agrochemicals that affect the environment. In this work, the techniques of biofumigation, solarization and biosolarization were evaluated in the production of American cucumber, under greenhouse conditions. Biofumigation is a technique that uses organic matter, for the control of soil-borne pathogens; while solarization consists of the heating of the soil to such temperatures that allow the control of pests and diseases; while the combination of both techniques (biofumigation + solarization) is called biosolarization. The experiment was carried out in a greenhouse located in the experimental field of the Department of Agriculture and Livestock of the University of Sonora, in Hermosillo, Sonora, Mexico. The design was randomized blocks with four treatments and four replicates. The evaluated treatments were biofumigation, solarization, biosolarization and the control. The variables evaluated were yield (kg m-2, boxes ha-1 and fruits plant-1) and fruit weight (g). As quality parameters the firmness of the fruit in kg cm-2, as well as length and diameter in cm, were quantified. The best treatment was biofumigation, which presented a higher number of fruits with 10.1 fruits plant-1 and a higher yield with 10.0 kg m-2 and 4,197 boxes ha-1; Followed by biosolarization, with 9.3 fruits plant-1 and a yield of 8.7 kg m-2 and 3,791 boxes ha-1. The quality parameters did notpresent significant differences between treatments.

RESUMEN El uso de medidas de control no contaminante se ha incrementado en los últimos años, permitiendo reducir la aplicación de agroquímicos que afectan el medio ambiente. En este trabajo se evaluó las técnicas de biofumigación, solarización y bio-solarización en la producción de pepino americano, bajo condiciones de invernadero. La biofumigación es una técnica que utiliza materia orgánica, para el control de patógenos del suelo; mientras que la solarización consiste en el calentamiento del suelo a temperaturas tales que permiten el control de plagas y enfermedades; en tanto que a la combinación de ambas técnicas (biofumigación+solarización) se le denomina biosolarización. El experimento se desarrolló en un invernadero ubicado en el campo experimental del Departamento de Agricultura y Ganadería de la Universidad de Sonora, en Hermosillo, Sonora, México. El diseño fue de bloques al azar con cuatro tratamientos y cuatro repeticiones. Los tratamientos evaluados fueron: biofumigación, solarización, biosolarización y el testigo. Las variables evaluadas fueron: rendimiento (kg m-2, cajas ha-1 y frutos planta-1) y peso del fruto (g). Como parámetros de calidad se cuantificó la firmeza del fruto en kg cm-2, al igual que la longitud y el diámetro en cm. El mejor tratamiento fue la biofumigación, el que presentó un mayor número de frutos con 10,1 frutos planta-1 y un mayor rendimiento con 10,0 kg m-2 y 4.197 cajas ha-1; seguido por la biosolarización, con 9,3 frutos planta-1 y un rendimiento de 8,7 kg m-2 y 3.791 cajas ha-1. Los parámetros de calidad no presentaron diferencias significativas entre tratamientos.

RESUMO Objetivou-se avaliar três tratamentos de restauração florestal em uma área com elevação periódica do lençol freático, no Corredor de Biodiversidade Santa Maria, localizado entre os municípios de Santa Terezinha de Itaipu e São Miguel do Iguaçu-PR. Os tratamentos foram: controle, adubação verde e solarização do solo. Foi realizado o acompanhamento mensal da mortalidade e desenvolvimento de 12 espécies arbóreas nativas da região e a persistência de duas espécies invasoras presentes na área, Megathyrsus maximus (capim-colonião) e Cyperus rotundus (tiririca). Além disso, avaliou-se as alterações promovidas no solo por meio de três coletas durante o experimento. Após um ano, os tratamentos não apresentaram diferenças estatísticas significativas sobre as avaliações realizadas. A mortalidade foi mais acentuada em janeiro (12,08%), com maior percentual para Cabralea canjerana (canjarana) e menor para Luehea divaricata (açoita-cavalo). Sobre o desenvolvimento das mudas, houve maior crescimento para: Sapium glandulatum (leiteiro-do-banhado), Croton urucurana (sangra-d'água) e Luehea divaricata, com acréscimos mensais em diâmetro de 3,66 mm a 4,12mm, e em altura de 12,39 cm a 17,02 cm. Em relação à massa seca do capim-colonião e tiririca em todos os tratamentos, os maiores valores foram verificados em janeiro (94,14 g m-2) e fevereiro (132,76 g m-2), mantendo-se baixos ao longo do experimento. Por meio das análises de solo, foi possível observar que os tratamentos não apresentaram diferenças significativas, contudo, as alterações físicas e químicas do solo mostraram-se sensíveis ao manejo das espécies invasoras, podendo levar a novas modificações durante o desenvolvimento das mudas.

ABSTRACT It was aimed to evaluate three treatments for forest restoration in an area with periodic elevation of the groundwater, in the Corredor de Biodiversidade Santa Maria, located between the cities of Santa Teresinha de Itaipu and São Miguel do Iguaçu, in Paraná state. The treatments were: control, green manure and soil solarization. It was performed a monthly monitoring of mortality and development of 12 tree native species of the region and the persistence of two invasive species present in the area, Megathyrsus maximus (coloniao grass) and Cyperus rotundus (coco grass). Furthermore, it was evaluated the changes introduced in the soil by three soil samples during the experiment. After over a year of assessment, the treatments showed no statistically significant differences on the evaluations. The mortality was more pronounced in January (12.08%), with a higher percentage for Cabralea canjerana (canjarana) and lower for Luehea divaricata (açoita-cavalo). About the seedlings development, growth was higher for: Sapium glandulatum (leiteiro-do-banhado), Croton urucurana (sangra-d'água) and Luehea divaricata, with monthly increases in diameter of 3.66 mm to 4.12 mm, and height of 12.39 cm to 17.02 cm. Regarding the dry mass of 'colonião' grass and coco grass (nutsedge) in all treatments, the highest values were found in January (94.14 g m-2) and February (132.76 g m-2), remaining low throughout the experiment. Through soil analyzes, it was observed that treatments showed no significant differences, however, the physical and chemical changes in the soil were sensitive to the invasive species management, which may lead to new modifications during the growth of seedlings.

RESUMO O controle de plantas daninhas é considerado o maior obstáculo para os produtores de cultivos orgânicos. A baixa produtividade das plantas na agricultura orgânica está relacionada, principalmente, ao mau controle de plantas daninhas. Já se sabe que, na maioria dos casos, as perdas causadas por essas plantas ultrapassaram as perdas provenientes de qualquer categoria de pragas agrícolas. Em condições de estresse hídrico, as plantas daninhas podem reduzir o rendimento das culturas em mais de 50% apenas por meio da competição por umidade. Diante dos problemas ambientais e toxicológicos criados por herbicidas, tornou-se necessário desenvolver métodos de segurança para controle de plantas daninhas. Solarização do solo, cobertura morta, cobertura morta biodegradável, herbicidas naturais, água quente e práticas agronômicas foram adotados com êxito em muitos países como métodos seguros para controle de plantas daninhas na agricultura orgânica. Além disso, existem algumas medidas promissoras novas e não tradicionais, como lentes de Fresnel, controle elétrico de plantas daninhas, laser etc., que podem ser empregadas para controlar as plantas daninhas na agricultura orgânica. Além disso, práticas agronômicas, como a escolha de variedades competitivas e canteiros falsos, tiveram impacto significativo sobre as plantas daninhas. Os produtores de agricultura orgânica devem ter em mente estes três aspectos: 1) começar de modo limpo e manter limpo de forma bemsucedida; 2) a prevenção é sempre melhor do que o tratamento; e 3) as sementes de um ano conduzirão à infestação por plantas daninhas durante sete anos. Os sistemas de manejo de plantas daninhas bem-sucedidos e sustentáveis são aqueles que empregam combinações de técnicas, em vez de depender de um único método. O objetivo deste artigo foi analisar alguns métodos seguros de controle de plantas daninhas em agricultura limpa.

ABSTRACT Weed control is consider the major obstacle for the growers in the organic farming. Lower plant productivity in organic farming mainly related to the poor weed control. It is widely known, in most cases, that losses caused by weeds exceeded the losses from any category of agricultural pests. Under water-stress condition, weeds can reduce crop yields more than 50% through moisture competition alone. In the light of the environmental and toxicological problems created by herbicides, it has become necessary to develop the safety methods for controlling weeds. Soil Solarization, Mulching, Biodegradable Mulch, Natural Herbicides, Hot Water, and Agronomic Practices have been successfully adopted in many countries as safe methods for controlling weeds in the organic farming. In addition, there are some promising new and non-traditional measures such as Fresnel Lens, Electrical Weed Control, Lasers, etc which could be employed for controlling the weeds in organic farming. Also the agronomic practices such as choice of competitive varieties, stale seedbeds had a significant impact on weeds. The growers in organic farming should keep these three points in mind: 1) start clean stay clean successful, 2) Prevention is always better than treatment and, 3) One year's seeds will lead to seven year's weed infestation. Successful and sustainable weed management systems are those that employ combinations of techniques rather than relying on one method. The objectives of this paper are to review some safe weed control methods in the clean agricultural.

Abstract: The objective of this study was to evaluate the yield and quality of phytochemical of basil (Ocimum basilicum L.) in different organic substrates under conditions of shade cloth. Organic fertilizers were evaluated; vermicompost (VER), compost (COM) and solarized manure (ES), mixed in different proportions with sand (A), pumice (P) and agricultural land (S). Six treatments with four replications were used in a completely randomized experimental design. The treatments were: T1, sand + solarized dung (80:20); T2 sand + solarized dung + soil (80: 15: 5); T3, sand + vermicompost (80:20); T4, sand + mineralized compost (80:20); T5, sand + vermicompost + soil (80: 15: 5) and; T6 (control) sand + pumice (80:20), with Steiner solution. Four cuts were made at 30, 71, 139 and 179 days after transplantation, the leaf area index was determined (LAI), fresh leaf weight (PFH), dry leafweight (PSH), fresh stem weight ( PFT) and dry stem weight (PST) as well as the total phenols and antioxidant capacity. Substrates in physical and chemical parameters were determined. The results showed significant differences (Tukey, p≤ 0.05) for yield, IAF, PSH, total phenols and antioxidant capacity. The phenolic content of the basil leaves were significantly different, with values of 62.42 and 41.55 mg equiv. Ac. Gallic 100 g in dry weight for T6 and T2, respectively. For the antioxidant capacity method ABTS+ significant difference was found with values of 156.43 and 101.86 (μM equiv Trolox / 100 g PF) obtaining the highest value T3 and the lowest T2. These organic treatments obtained the highest phenolic content and antioxidant capacity, which were similar to the phytochemical quality of the product obtained under traditional fertilization (Steiner solution), indicating the feasibility of organic treatments for their low cost for implementing of the basil organic production in shade cloth.

Resumen: El objetivo del presente estudio fue evaluar el rendimiento y la calidad fitoquimica de albahaca (Ocimum basilicum L.) en diferentes sustratos orgánicos bajo condiciones de malla sombra. Se evaluaron los abonos orgánicos; vermicompost (VER), compost (COM) y estiércol solarizado (ES), mezclados en diferentes proporciones con arena (A), piedra pómez (P) y suelo agrícola (S). Se utilizaron seis tratamientos con cuatro repeticiones en un diseño experimental completamente al azar. Los tratamientos fueron: T1, arena+estiércol solarizado (80:20); T2, arena + estiércol solarizado + suelo (80:15:5); T3, arena + vermicompost (80:20); T4, arena + compost mineralizada (80:20); T5, arena + vermicompost + suelo (80:15:5) y T6 (testigo), arena + piedra pómez (80:20), con solución Steiner. Se evaluaron cuatro cortes a los 30, 71, 139 y 179 días después del trasplante, se determinó el índice de área foliar (IAF), peso fresco de hoja (PFH), peso seco de hoja (PSH), peso fresco de tallo (PFT) y peso seco de tallo (PST), así como fenoles totales y capacidad antioxidante. En los sustratos se determinaron parámetros físicos y químicos. Los resultados mostraron diferencias significativas (Tukey; p≤ 0.05) para rendimiento, IAF, PSH, fenoles totales y capacidad antioxidante. El contenido fenólico de las hojas de albahaca presentaron diferencias significativas, con valores de 62.42 y 41.55 mg equiv. de Ac. Gálico 100 g en peso seco para T6 y T2, respectivamente. Para la capacidad antioxidante método ABTS+ se encontró diferencia significativa con valores de 156.43 y 101.86 (μM equiv Trolox / 100 g PF) obteniendo el mayor valor el T3 y el menor T2, respectivamente. Estos tratamientos orgánicos obtuvieron el mayor contenido fenólico y capacidad antioxidante, los cuales resultaron similares a la calidad fitoquímica del producto obtenido bajo fertilización tradicional (solución Steiner), lo cual indica la factibilidad de los tratamientos orgánicos por su bajo costo en la implementación de la producción orgánica de albahaca en malla sombra.

RESUMO A irrigação suplementar e a cobertura do solo ("mulching") são práticas de manejo comumente usadas na agricultura. O objetivo deste trabalho foi quantificar a temperatura do solo desnudo com e sem irrigação, e sob diferentes coberturas do solo. Um ensaio de campo foi conduzido em Santa Maria-RS (29o 43' S latitude, 53º 42' W longitude e 95 m de altitude), com seis diferentes áreas: solo desnudo sem e com irrigação, solo com "mulching" de plástico transparente (espessura 100 µm), "mulching" de plástico opaco preto (espessura 110 µm), "mulching" de plástico opaco branco (espessura 150 µm) e cobertura vegetal com palha na dose de 5 t ha-1. A temperatura do solo foi medida a 0,05 m de profundidade, diariamente, às 15h (18 UTC), no período de 10-10-2011 a 31-05-2012. Foram também realizadas medidas horárias de temperatura do solo em quatro dias sem nebulosidade, em outubro e novembro de 2011, e janeiro e março de 2012. A temperatura do solo diurna seguiu a sequência: plástico transparente (42,4 oC) > plástico opaco preto (37,8 oC) > solo desnudo sem irrigação (33,4 oC) > solo desnudo com irrigação (29,2oC) > palha (27,0 oC) > plástico opaco branco (24,6 oC). A região de Santa Maria-RS, tem potencial físico de aquecimento do solo com a técnica da solarização.

ABSTRACT Supplemental irrigation and mulching are management practices commonly used in agriculture. This study aimed to quantify soil temperatures in bare and covered soils with and without irrigation. The evaluations were carried out in Southern Brazil (Santa Maria–RS). The experimental area was divided into six treatments consisting of bare soil with irrigation, bare soil without irrigation, and soil-covered areas using transparent plastic mulch (100 μm), black opaque plastic mulch (110 μm), white opaque plastic mulch (150 μm) and straw at a rate of 5 t ha-1. Soil temperature readings were taken once daily at 5 cm depth at 3 pm (18 UTC) from October 10, 2011 to May 31, 2012. Moreover, hourly measurements were also made during four sunny days (cloudless sky) in October, November, January and March. Daytime soil temperature decreased as the following sequence: transparent plastic (42.4 °C), black opaque plastic (37.8 °C), bare soil without irrigation (33.4 °C), bare soil with irrigation (29.2 °C), straw covering (27.0 °C) and white opaque plastic (24.6 °C). Soil solarization is a potential mulching method to increase soil temperature in Santa Maria–RS, Brazil.

Objetivou-se, nesta pesquisa, testar métodos de superação da dormência além de avaliar a eficiência do uso de fungicida no armazenamento de diásporos de teca que já sofreram tratamentos pré-germinativos. O delineamento experimental foi o inteiramente casualizado em esquema fatorial 7 x 2 x 2 (sete métodos de superação; com e sem fungicida e dois tempos de avaliação, zero e após 120 dias). Os métodos utilizados foram: imersão em água corrente (24 h) e em água quente (85-90 ºC por 8 min); escarificação com lixa + imersão em água parada (48 h); escarificação com ácido sulfúrico por 15 min + água corrente (72 h); aquecimento em estufa a 80 ºC (4 h por 3 dias) + imersão em água parada (12 h); solarização por 48 h + imersão em água parada (12 h) além da testemunha. Os métodos de superação com aquecimento a seco dos diásporos de teca são capazes de abreviar, aumentar e uniformizar a germinação sendo o uso do solarizador uma boa opção por não consumir energia e ser de baixo custo. O uso do fungicida Fludioxonil + Metalaxyl-M e o armazenamento de diásporos de teca que já sofreram tratamento de quebra da dormência, não são recomendados.

The objective of this research was to test methods of breaking dormancy, besides to assess the efficiency of fungicide in storage of teak diaspores which suffered pre-germination treatments. The experimental design was in completely randomized factorial scheme 7 x 2 x 2 (seven methods of dormancy breaking, with and without fungicide; two stages of evaluation , zero and after 120 days). The methods employed were: immersion in running water (24 h) and in hot water (85-90 ºC for 8 min); scarification with sandpaper + immersion in standing water (48 h); scarification with sulfuric acid for 15 min + running water washing (72 h); heating in oven at 80 ºC (4 h for 3 days) + standing water immersion (12 h); solarization for 48 hours + standing water immersion (12 h); and the control. The methods of dormancy breaking with dry heating of the teak fruits were able to shorten, increase, and standardize the germination, being the use of the solar collector a good choice for not consuming energy and of low cost. The use of Fludioxonil + Metalaxyl-M fungicide and the storage of teak diaspores which have suffered dormancy breaking treatment are not recommended.

The Laguna Region located in the states of Durango and Coahuila, Mexico, is the main cow milk production region of Mexico. Here there are about 500000 heads of cattle. This region produces about 1.2 million tons of cattle manure annually, which allows raising the possibility of their use in agriculture. Treatments evaluated in this study were: plant density (120000 and 240000 plants/ha), solarized cattle manure (0, 40, 80, 120 t/ha), and an additional chemical treatment of 120-60-00 kg/ha of nitrogen, phosphorus and potassium, respectively. A randomized block design with a strip arrangement was used. Three replicates were used per treatment. The objective of this study was to determine the solarized dose cattle manure and the best planting density in cotton production during the phenological development of the crop. The evaluated variables were: yield, soil moisture and temperature, and fber quality. The results indicated that the highest yield was for treatment of 80 t/ha with 120000 plants/ha. The highest temperature occurred at 0-7.5 cm soil depth in the dose of 120 t/ha, with a mean of 37.75 °C.

La Comarca Lagunera localizada en los Estados de Durango y Coahuila, México, es la principal cuenca lechera del país, con alrededor de 500000 vacas que producen cerca de 1,2 millones de toneladas de estiércol anualmente. Este abono puede utilizarse en la producción agrícola para reducir la utilización de productos químicos, reduciendo costos de producción, índices de contaminación y mejorar las características físico-químicas de los suelos, dándoles un manejo sustentable. Esta es una región históricamente algodonera, donde actualmente se siembran 30 mil hectáreas del cultivo. La aplicación de estiércol al suelo es una opción rentable para los agricultores. Los factores de estudios que se evaluaron fueron densidad de siembra (120000 y 240000 plantas/ha) y estiércol bovino solarizado (0, 40, 80, 120 t/ha), y un tratamiento químico de 120-60-00 kg/ha de N-P-K. Se utilizó un diseño de bloques al azar con arreglo en franjas con tres repeticiones. El objetivo de este estudio fue determinar la dosis de estiércol bovino solarizado, así como la mejor densidad de siembra en la producción de algodón durante el desarrollo fenológico del cultivo. Las variables evaluadas fueron: rendimiento, humedad y temperatura del suelo y calidad de fibra. En lo referente a rendimiento, el tratamiento que obtuvo los más altos resultados fue el de 80 t/ha con 120000 plantas/ha. La temperatura más alta ocurrió a 0-7,5 cm de profundidad del suelo en la dosis de 120 t/ha con una media de 37,75 °C. En calidad de fibra no existió diferencia entre tratamientos.

Un factor determinante en la disminución del rendimiento de la cebolla (Allium cepa L.) es la enfermedad raíz roja causada por Pyrenochaeta terrestris. Una alternativa en el control de esta enfermedad es la solarización del suelo, la cual constituye una medida erradicativa de patógenos. En un ensayo de campo llevado a cabo en suelo naturalmente infestado con Pyrenochaeta terrestris (Hansen) en Quíbor, estado Lara, Venezuela, se evaluó el efecto de la solarización (calentamiento del suelo por medio de su cubrimiento con láminas plásticas transparentes), adición de abonos verdes y la combinación de ambos tratamientos sobre la incidencia y la severidad de la raíz roja en cebolla. Se utilizó un diseño experimental en bloques al azar con seis repeticiones y un arreglo en parcelas divididas, en donde en las parcelas principales fueron ubicados los tratamientos de solarizado y no solarizado y en las subparcelas los abonos verdes (canavalia, Canavalia sp.; crotalaria, Crotalaria sp. y soya, Glycine max L.). La cobertura del suelo durante 45 días redujo la incidencia y la severidad de la enfermedad; en el suelo solarizado la incidencia fue 18,16 % y en el no solarizado fue 52,33 %, diferencia que representa un 65,29 % de control de la enfermedad. Con respecto a la severidad, hubo una reducción cercana al 12 % con la solarización. Las temperaturas logradas en el suelo solarizado fueron 4,6-10,9 °C mayores a las del suelo no solarizado. La solarización del suelo por sí sola fue efectiva para el control de la raíz roja, y la aplicación de abonos verdes no agregó ningún efecto sobre este control.

A determining factor in the decrease in the yield of onion (Allium cepa L.) is the pink root disease caused by Pyrenochaeta terrestris (Hansen). An alternative in the control of this disease is the solarization of soil, which is an erradicative measure of pathogens. A field experiment was carried out in naturally infested soil with Pyrenochaeta terrestris in Quíbor, Lara State, Venezuela, to determine the effect of solar heating in the soil by means of mulching with transparent polyethylene sheets, green manure applications, and combination of both treatments on the incidence and severity of onion pink root disease. A split-plot experiment was conduced, where main plots comprised those with presence and absence of solarization, and subplots were a factorial combination of green manure (Canavalia sp., Crotalaria sp., Glycine max L.) with and without solarization. There were six replications. The mulching of the soil with transparent polyethylene sheets for 45 days resulted in a decrease of the incidence and severity of disease, in solarized soil the incidence was 18.16 % and in non solarized soil was 52.33 %; this difference represents 65.29 % of disease control. With respect to the severity, there was a reduction close to 12% with solarization. Soil temperatures in the mulched soil varied from 4.6 to 10.9 °C higher than in unmulched soil. Soil solarization was effective for the control of pink root, and green manure application did not provide any additional effect for the disease control.