Resumen

RUIZ-SANCHEZ, C.A.. Effect of the dose and form of placement of the potassium about the physical quality of fruits of tomato (Lycopersicon esculentun Mill.) stored dos temperatures. Rev. Fac. Agron. [online]. 2006, vol.23, n.4, pp.483-497. ISSN 0378-7818.

The effect of three levels of potassium was studied; 0, 220 and 330 kg.ha^-1, placed in three different forms (central, lateral and in the bottom of the furrow) about the physical quality of tomato fruits stored 10 ± 2ºC and 15 ± 2ºC. They were sowed plants of tomato cv. Río Grande, in the sector Guarabal, Municipality Federation of the State Falcon and fruits were harvested in having been physiologically mature, which were identified and they stored for 21 days under the two temperatures, where every 7 days the color was evaluated using an spectrophotometer Colorimeter, which was registered using the system CIE- L a* b*, where L indicates brightness, with zero values (black) at a hundred (white), a * cromaticidad of an axis of green (-) to red (+) and b * cromaticidad in an axis of blue (-) to yellow (+), to determine the color predominance. The consistency was evaluated with a Twing Albert. A design was used totally at random with factorial arrangement and three replications. Under both conditions of temperature, the averages of L were smaller with the days of storage (dda) indicating the presence of darker colors. In the 330-lateral treatment under 15ºC was the biggest proportion of red color evaluated as index a*, as well as the smallest value in b*, indicating smaller proportion of yellow tones. The smallest storage temperature slowed the appearance of red colors, characteristic of the maturation of the tomato fruit. The fruits stored 15ºC presented smaller consistency in relation to those stored 10ºC. The treatments didn't influence in the consistency, but the temperature if.

Palabras clave : tomato; potassium; color; physical quality.