Monitoreo descriptivo de parásitos de origen fecal hallados en hortalizas de hojas

p.271-276El objetivo de este trabajo fue contabilizar la presencia de protozoos, huevos y larvas de helmintos en muestras de hortalizas de hoja para consumo fresco, que se comercializan en el Mercado Central de Buenos Aires. Las especies analizadas fueron: lechuga, radicheta, berro y perejil. Las muestras se procesaron por los métodos de Baerman y Flotación. Los resultados obtenidos indican que: 1- Existe contaminación parasitaria: sobre un total de 98 muestras analizadas durante 12 meses, el 27,5por ciento estaban contaminadas. 2- La especie más contaminada fue berro (66,7por ciento), luego radicheta (31,8por ciento), lechuga (21,4por ciento) y, finalmente, perejil (13,6por ciento). 3- El parásito más frecuente fue Entamoeba coli (44,4por ciento) y en segundo término E.hystolitica (22,4por ciento). 4- El sur y sudoeste del conurbano bonaerense fue la zona de mayor contaminación (66,6por ciento). La presencia de los contaminantes en las hortalizas estudiadas demuestra el desconocimiento de los riesgos potenciales que ciertas prácticas agrícolas pueden acarrear a los consumidores

Интеграция малого инновационного бизнеса в систему особых экономических зон

В рамках деятельности по стимулированию и развитию малого бизнеса на протяжении уже довольно длительного времени проводились разного рода меры. Однако на сегодняшний день доля малого и среднего бизнеса не превышает 21% ВВП. В структуре малого бизнеса преобладают предприятия, занятые в торговой сфере, а доля инновационных предприятий ничтожна мала. Проблему развития малых инновационных предприятий и повышения их экономической эффективности, необходимо решать путем интеграции данных предприятий с институтом особой экономической зоны технико-внедренческого типа

A bifunctional dermaseptin–thanatin dipeptide functionalizes the crop surface for sustainable pest management

To reduce pesticide use while preserving crop productivity, alternative pest and disease control measures are needed. We thought of an alternative way of functionalizing leaves of soybean to fight its most severe disease, Asian soybean rust (Phakopsora pachyrhizi). To do so, we produced bifunctional peptides that adhere to the soybean leaf surface and prevent the germination of P. pachyrhizi spores. In detail, amphiphilic peptides liquid chromatography peak I (LCI), thanatin (THA), tachystatin A2 (TA2), and lactoferricin B (LFB) were all fused to enhanced green fluorescent protein (eGFP). Of these fusion peptides, eGFP–LCI and eGFP–THA bound strongly and in a rainfast manner to the surface of soybean, barley, and corn leaves. eGFP–THA binding to soybean also withstood high temperature, sunlight and biotic degradation for at least 17 days. The dipeptides seem to bind mainly to the surface wax layer of leaves because eGFP–THA and eGFP–LCI did not stick to the wax-depleted cer-j59 mutant of barley or to corn leaves with their surface wax removed. A fusion of the antimicrobial peptide dermaseptin 01 and THA (DS01–THA) inhibits the germination of P. pachyrhizi spores in vitro and reduces Asian soybean rust disease in a rainfast manner. Therefore, this study reveals that bifunctional peptides can be used to functionalize the crop surface for sustainable disease management

Identification of novel nonhost resistance genes in the interaction between Arabidopsis thaliana and Asian soybean rust

Nonhost resistance (NHR) is the most durable form of plant immunity and is effective against all genetic variants of a pathogen. NHR wards off non-adapted pathogens using pre- and postinvasion defenses. In Arabidopsis, PEN2 is required for preinvasion resistance to the Asian soybean rust fungus Phakopsora pachyrhizi while PEN2, PAD4, and SAG101 together are needed for postinvasion NHR in the mesophyll. Transcriptional profiling of infected and mock-treated Arabidopsis wild type, pen2 and pen2 pad4 sag101 mutants identified 24 novel putative NHR genes whose expression is specifically associated with postinvasion mesophyll resistance to P. pachyrhizi. In the Arabidopsis pen2 mutant, individual silencing or mutation of candidate NHR genes CL4, CL7, CL15, CL16 (BRT1; UGT84A2), CL22 and CL23 attenuated postinvasion mesophyll resistance to P. pachyrhizi. Furthermore, stable overexpression of individual candidate genes (CL4, CL7, CL13,CL22 and CL24) in the soybean host conferred enhanced immunity to the rust fungus. Hence, evidence is provided that transfer of Arabidopsis NHR genes can significantly improve pathogen resistance of crop plants. Genes identified in this study will be used in future breeding programs for production of soybean varieties with durable resistance to Asian soybean rust

Identification of novel nonhost resistance genes in the interaction between Arabidopsis thaliana and Asian soybean rust

Nonhost resistance (NHR) is the most durable form of plant immunity and is effective against all genetic variants of a pathogen. NHR wards off non-adapted pathogens using pre- and postinvasion defenses. In Arabidopsis, PEN2 is required for preinvasion resistance to the Asian soybean rust fungus Phakopsora pachyrhizi while PEN2, PAD4, and SAG101 together are needed for postinvasion NHR in the mesophyll. Transcriptional profiling of infected and mock-treated Arabidopsis wild type, pen2 and pen2 pad4 sag101 mutants identified 24 novel putative NHR genes whose expression is specifically associated with postinvasion mesophyll resistance to P. pachyrhizi. In the Arabidopsis pen2 mutant, individual silencing or mutation of candidate NHR genes CL4, CL7, CL15, CL16 (BRT1; UGT84A2), CL22 and CL23 attenuated postinvasion mesophyll resistance to P. pachyrhizi. Furthermore, stable overexpression of individual candidate genes (CL4, CL7, CL13,CL22 and CL24) in the soybean host conferred enhanced immunity to the rust fungus. Hence, evidence is provided that transfer of Arabidopsis NHR genes can significantly improve pathogen resistance of crop plants. Genes identified in this study will be used in future breeding programs for production of soybean varieties with durable resistance to Asian soybean rust