Abstract The agricultural sector in the country has a high and growing status and importance, but the growth and development of this sector are not possible without proper and effective risk management. In the current study, using the Monte Carlo simulation method as one of the powerful tools in risk analysis, the production risk due to the effects of climate change on the dominant agricultural products of Plovdiv, Bulgaria in the period 1990-2017, is predicted and measured. The results showed that Lentils has the highest risk (Product risk index was -0.25%) and bean has the lowest risk (Product risk index was 0.17%). Overall, the research results indicate the significant effect of performance risk in this region. Therefore, farmers should pay special attention to the risk of crop performance in determining their cultivation pattern in addition to other factors and criteria such as price, profitability, self-consumption, etc. Meanwhile, it is suggested that products with higher risk should not be grown alone and should be placed next to the other products with less risk as much as possible to increase food security.

Abstract The research summarized and validated the individual selection of camu-camu (Myrciaria dubia (Kunth) McVaugh) plants. 43 progenies, previously selected in genetic tests and fields of producers of flood areas, were evaluated. Each progeny was installed in a row of 10 half-sister plants, with a space of 3x2 m. Using the SELEGEN (Reml / Blup) Model 63 program, four crops were analyzed, and individuals were selected for each of the 16 descriptors evaluated. For fruit yield, the Tipishca-Río Tigre population stood out, occupying 5 of the first 10 places. The individuals TT0725-4 (Tigre-Tipishca) turned out to be a natural recombinant for fruit yield / weight. And individual 64-8 turned out to be triple recombinant (yield / fruit weight / ascorbic acid). The descriptors with the highest genetic control with r ≥ 0.30 were: average fruit weight, brix degrees, plant height, number of basal branches and petiole length. The criteria of similarity of the morphological markers with the fruit yield are proposed as predictive indexes of productivity. The plant height at two years of age was the most important.

Resumen El objetivo en este estudio fue determinar el contenido de nutrientes en plantas de Myrciaria dubia como respuesta a la aplicación de cinco dosis de K2O (0; 40; 80; 120 e 160 kg ha-1) aplicadas por fertirrigación. Se evaluaron los contenidos de materia seca de hoja (MSH), materia seca total (MST) y el contenido de nutrientes en las hojas. La MSH y la MST fueron mayores en plantas fertilizadas con la dosis de 160 kg ha-1 de K2O, con 52.44 g y 302.69 g, respectivamente. Los contenidos de N y K fueron de 22.15 y 9.48 g kg-1 en respuesta a la dosis de 160 kg ha-1 de K2O. Los contenidos medios de P, Ca y S fueron de 1.6, 17.89 y 1.61 g kg-1, respectivamente, y el contenido de Mg2+ disminuyó desde 5.62 hasta 2.74 g kg-1 en la dosis de 0 y 160 kg ha-1 de K2O, respectivamente. Los contenidos de B, Mn y Fe disminuyeron de 136.5 a 100.0, de 346.24 a 248, y de 142.06 a 97.35 mg kg-1 en la dosis de 0 y 160 kg ha-1 de K2O, respectivamente. Los contenidos medios de Cu y Zn fueron 3,81 y 40,54 mg kg- 1, respectivamente, en todas las dosis de K2O. El contenido de nutrientes determinado en las hojas de M. dubia fueron adecuados para el desarrollo de la especie en el primer año de cultivo, presentando el siguiente orden decreciente: N> Ca> K> Mg> P = S> Mn> B > Fe> Zn> Cu.

Abstract The objective in this study was to determine the nutrient contents in Myrciaria dubia plants in function of five K2O doses (0, 40, 80, 120 and 160 kg ha-1) applied through fertigation. Leaf dry matter (LDM), total dry matter (TDM), and leaf nutrient contents were evaluated. The LDM and TDM were higher in plants subjected to the dose of 160 kg ha-1 of K2O, with 52.44 g and 302.69 g, respectively. Leaf N and K contents were 22.15 and 9.48 g kg-1 in response to 160 kg ha-1 of K2O. The mean P, Ca and S contents were 1.6, 17.89 and 1.61 g kg-1, respectively, and the content of Mg2 + decreased from 5.62 to 2.74 g kg-1 at the dose of 0 and 160 kg ha-1 of K2O, respectively. The B, Mn and Fe contents decreased from 136.5 to 100.0, 346.24 to 248, and from 142.06 to 97.35 mg kg-1 at the dose of 0 and 160 kg ha-1 of K2O, respectively. The mean Cu and Zn contents were 3.81 and 40,54 mg kg-1, respectively, at the K2O doses. The nutrient content determined in the leaves of M. dubia were adequate for the development of the species in the first year of cultivation, presenting the following decreasing order: N> Ca> K> Mg> P = S> Mn> B> Fe > Zn> Cu.