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In this paper are studied two soil profiles from the soil map in scale 1:25 000 of the fluvial plain region Carrizal-Chone, in Manabi province, Ecuador. One of profiles is a soil fluvic Feozem by tree vegetation and the other is a fluvic eutric Cambisol by long time cultivated condition. It is studied the changes of the physical soil properties by the anthropogenic conditions, with changes in the soil structure, volume density, and the increasing of the dispersion factor. In this paper is demonstrated the change from a Feozem soil to a Cambisol soil because the long time cultivated action [ABSTRACT FROM AUTHOR]

The pumpkin (Cucurbita pepo L.), of American origin, represents one of the most used species today. Mexico is an important center of origin, domestication and diversification of the genus Cucurbita. Pumpkin production in Mexico places it in sixth place. This crop has as main limitation for its production the incidence of different harmful organisms, where foliar diseases of fungal origin are the most important, where powdery mildew stands out with economic losses of 50 to 100 %. For proper management, an important element is the correct identification of the causal agent, since two different genera and species are associated with the disease. Worldwide, the identified species that infect the Cucurbitaceae family are Podosphaera fusca (Fr.) Braun &. Shishkoff (syn.: Sphaerotheca fusca (Fr), Podosphaera xanthii (Castagne) U. Braun & Shishkoff) or Golovinomyces cichoracearum (DC.) V.P. Heluta. The control of the pathogen has been carried out mainly with the use of fungicides. However, its use causes negative effects on the biodiversity of agroecosystems, which can cause irreversible damage to the environment, increase production costs and enhance fungus resistance. Hence the importance of seeking new alternatives for its management, such as the use of oils, salts and biological control agents. This paper presents a review related to the updated identification of pumpkin powdery mildew, as well as trends in its management. [ABSTRACT FROM AUTHOR]