Manuel Silva Valenzuela

Dr. Manuel Silva Valenzuela

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Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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18 August 2022 in Insects
Verified
Journal Article
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MVManuel Silva Valenzuela
Manuel Silva Valenzuela
RRReyna Isabel Rojas-Martínez
Reyna Isabel Rojas-Martínez
VZVictor Manuel Zuñiga-Mayo
Victor Manuel Zuñiga-Mayo
Chili pepper is a vegetable of worldwide economic and gastronomic importance. The psyllid, Bactericera cockerelli, is an economically important pest in this crop, causing considerable losses in its production. Currently, the application of insecticides is the main way to control B. cockerelli. However, the use of varieties resistant to this insect is a viable alternative for its control and management. In this work, the oviposition rate, development, and survival of B. cockerelli in two native varieties of chili were evaluated. Choice and non-choice trials showed that the B. cockerelli oviposition was reduced on CJ-2018 by 92.17 and 80.18%, respectively, compared to the control. In CM-334, the insect showed a behavior similar to the control in the non-choice test, while in the choice test it laid more eggs on CM-334 compared to the control. The development and survival assay showed that only 1.33% of the eggs managed to reach the adult stage on CJ-2018. In contrast, on CM-334 the survival of B. cockerelli was similar to the control. These results suggest that CJ-2018 presented a resistance based on antixenosis and antibiosis against B. cockerelli.

30 October 2026 in Journal of Plant Diseases and Protection
Verified
Journal Article
Closed access
ONO. Nabor-Romero
O. Nabor-Romero
MVManuel Silva Valenzuela
Manuel Silva Valenzuela
RRReyna Isabel Rojas-Martínez
Reyna Isabel Rojas-Martínez

14 September 2026 in Fungal Biology
Verified
Journal Article
Open access
AAAlfonso Daniel Victoria Arellano
Alfonso Daniel Victoria Arellano
GMGuillermo Márquez-Licona
Guillermo Márquez-Licona
ASAlma Rosa Solano-Báez
Alma Rosa Solano-Báez
OROlivia Nabor Romero
Olivia Nabor Romero
MVManuel Silva Valenzuela
Manuel Silva Valenzuela
LDLeandro José Dallagnol
Leandro José Dallagnol
In Southern Brazil, Lolium multiflorum is a crucial winter crop due to its nutritional properties for livestock and availability during periods of food shortage. However, fungal diseases like gray leaf spot (GLS), brown leaf spot (BLS), and rust (RU) threaten the crop yield. Adjusting cutting regimes is a low-cost disease management strategy. Nonetheless, its effects on foliar pathogens and subsequent seed contamination remain unclear. Therefore, this study assessed how different numbers of cuttings influence the progress of foliar diseases and the incidence of seed-borne fungi. In this sense, a randomized block design tested four treatments: uncut control (0C), one cutting (1C), two cuttings (2C), and three cuttings (3C). Foliar disease severity and incidence were monitored over 69 days. The area under the disease progress curve (AUDPC) was calculated for each disease. At harvest, seeds were analyzed using blotter tests to detect fungal contamination. The AUDPC for the 3-cutting treatment was reduced by 70% for GLS and 76% for RU compared with the no-cutting treatment. Saprophytic fungi (Alternaria spp., Cladosporium spp.) dominated seeds under high cutting regime (up to 86% incidence). Increasing the number of cuttings, from one to three cuttings, suppressed foliar diseases but shifted the seed-associated fungal community, such as Alternaria spp. Because increasing the number of cuttings alone cannot control this shift, integrated strategies are needed to balance both outcomes.

6 July 2020 in Przegląd Prawa Rolnego
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Journal Article
Closed access
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MVManuel Silva Valenzuela
Manuel Silva Valenzuela
The current article is divided in two parts. On a practical level, the interest of this research is to offer alternative solutions to the gaps in the regulatory framework of the Nicaraguan agricultural market, which pave the way for an unequal distribution of the economic resources generated by the national agricultural activity, in the agri-food supply chain. The objective was to determine the legal gaps that allow the unequal distribution of resources in the national agri-food supply chain and propose possible alternatives based on the agrarian doctrine. For this purpose, using analysis-synthesis, abstract-concrete, systemic-structural-functional and inductive-deductive analyses, the systems of marketing agricultural products in the countries of Central America and Nicaragua was examined and compared. As practice shows, small producers of food are not adequately protected and when it comes to commercial relationships their position is weak in the overall agri-food supply chain.