Relationship between degree-days and the production of Opuntia ficus-indica for human consumption in Marin, Nuevo León

Abstract

Air temperature is the most related factor to plant growth and development. There are few investigations reported for growing cactus in northern Mexico that address modeling degree days with biomass production under hydroponic conditions. The objectives of this study were: i) production modeling of cactus pear related to fresh (PF) and dry (PS) biomass, with air temperature; and ii) estimate the rate of biomass growth in a closed hydroponic system. The experiment was conducted in (2009) in Marin, Nuevo Leon, Mexico. The variety “Villanueva” was used, with a population density of 16 plants m-2, a substrate of river sand and a complete nutrient solution. Irrigation was made every third day and the solution was renewed every week. The average values of temperature, relative humidity and degree day in the harvest period were: 29 oC, 55% RH and 558.2 degree days, respectively. Only two cladodes were left to maturity on the mother cladode and from them were harvested each week all shoots when they reached 15 cm or more in length. The ratio of PF, PS vs. degree days (GD) variables were adjusted to quadratic polynomials with R2= 0.83 and 0.91, respectively; the rate of increase was variable during the crop production cycle. The average monthly production of 16 plants was 4.36 and 0.72 kg m-2 of PF and PS, respectively.