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xxx F.A. Damasceno, J.A. Osorio, C.E. Alves Oliveira, P.F.P. Ferraz and L.F. Brandão
Assessment of a low-cost solar water heating systems in farrowing facilities
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Assessment of a low-cost solar water heating systems in farrowing facilities

F.A. Damasceno¹*, J.A. Osorio², C.E. Alves Oliveira¹, P.F.P. Ferraz¹ and L.F. Brandão³

¹Department of Engineering, Federal University of Lavras, BR37200-000 Lavras - Minas Gerais, Brasil
²University National of Colombia, Faculty of Agrarians Science, Department of Agricultural and Food Engineer, Calle 59 A N 63-20, CO050001 Medellín, Colombia
³Department of Engineering, Federal University of Ouro Preto, BR35400-000 Ouro Preto – Minas Gerais, Brasil
*Correspondence: flavio.damasceno@deg.ufla.br

Abstract:

The objective of this study was to develop a prototype solar heater using alternative materials and then to compare its thermal efficiency against that of two other commercial solar heating systems when heating the floor of piglet housing. To evaluate the thermal heaters, temperature sensors were installed in the inlet and outlet of each floor and the thermal reservoir. The results showed good performance, however the thermal efficiency of the alternative heater was lower than the conventional systems. However, due to the construction of this solar collector with alternative materials its cost was relatively low and its operation is easier than the other conventional heater, therefore this heater is a good alternative to use for small livestock producer.

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xxx O. Gayosso-Barragán, A. López-Benítez, S.A. Rodríguez-Herrera, J.N. Ek-Maas, D.M. Hidalgo-Ramos and J.S.G.J. Alcala-Rico
Studies on combining ability in tomato (Solanum lycopersicum L.)
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Studies on combining ability in tomato (Solanum lycopersicum L.)

O. Gayosso-Barragán, A. López-Benítez*, S.A. Rodríguez-Herrera, J.N. Ek-Maas, D.M. Hidalgo-Ramos and J.S.G.J. Alcala-Rico

Universidad Autónoma Agraria Antonio Narro, Departamento de Fitomejoramiento, Calzada Antonio Narro 1923, MX25315 Saltillo, Coahuila, México
*Correspondence: alfopezbe_2000@hotmail.com

Abstract:

The present study was done seven elite tomato lines (Solamun lycopersicum L.) of determinate and indeterminate growth with good yield potential and good combining ability, using diallel fashion without reciprocals to produce 21 F1s. General combining ability (GCA) and Specific combining ability (SCA) analysis were conducted, with Diallel-SAS, assessing six yield and component traits. Results showed highly significant differences (p ≤ 0.01) among genotypes, as well as in GCA and SCA effects in all the characteristics that was assessed, with the exception of Days to First Cut. The results revealed that variance contribution to the yield attributed to the crossings had more non-additive effects (SCA) than additive effects (GCA). Furthermore, Line D4 had the greatest effect on yield in terms of GCA, as well in AFW (Average Fruit Weight), NFP (Number of Fruits per Plant) and PD (Polar Diameter) followed by D3 and K3. These lines can be used as donor parent in future tomato-breeding program. Hybrids K3×D4, R1×Y53, D3×IR13 and F3×Y53 had the highest level of SCA, with average yields of 93 t ha-1. These potential hybrids could be exploited at commercial level after critical testing.

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