不同温度条件下玉米呼吸速率变化的研究

通过对3种不同水分(偏低水分11.8%、安全水分13.3%和偏高水分16.3%)的玉米在4种不同温度(15℃、20℃、25℃和30℃)条件下,自身呼吸消耗O2的百分含量的测定,研究密闭储藏环境条件下玉米粮粒呼吸速率的变化规律。20L规模的试验室研究结果表明:玉米的呼吸速率随储藏时间和氧浓度变化均呈非线性变化,在同一温度条件下,含水量越高的玉米粮粒呼吸速率越快,对相同水分的玉米粮粒,温度越高呼吸速率越快。15℃条件下呼吸速率的变化情况为:偏低水分0.047~0.431mL·g·d-1、安全水分0.059~0.574mL·g·d-1、偏高水分0.071~0.707mL·g·d-1;20℃条件下呼吸速率的变化情况为:偏低水分0.143~0.520mL·g·d-1、安全水分0.183~0.734mL·g·d-1、偏高水分0.173~0.707mL·g·d-1;25℃条件下呼吸速率的变化情况为:偏低水分0.199~0.910mL·g·d-1、安全水分0.192~1.170 mL·g·d-1、偏高水分0.241~1.197mL·g·d-1;30℃条件下呼吸速率的变化情况为:偏低水分0.194~1.360mL·g·d-1、安全水分0.203~1.541mL·g·d-1、偏高水分0.256~1.964mL·g·d-1;相同水分的玉米粮粒呼吸速率随氧浓度的降低而减弱。通过对玉米粮粒呼吸速率随时间的变化和氧浓度的变化趋势线进行回归分析,得到不同温度条件下不同水分玉米呼吸速率的回归方程,利用相应回归方程,可获得密闭环境条件下储藏玉米在不同时间以及不同氧浓度条件下的呼吸速率,为气调储藏时玉米粮粒自呼吸的合理利用提供基础技术参数和数据模型。

STUDY ON CHANGES OF MAIZE RESPIRATION RATE UNDER DIFFERENT TEMPERATURE CONDITIONS

The purpose of the study was to examine variation of maize respiration rate by determining O2 content in percentage released due to respiration consuming O2 under hermetic storage conditions, based on three different moisture contents of maize （low moisture 11.8%, safe moisture 13.3% and high moisture 16. 3%） in four different temperatures （15℃,20℃,25℃ and 30℃）. The results obtained from the 20L-scale experiments have demonstrated that respiration rate of maize has nonlinear relationship to storage time and oxygen concentration in self--regulated environment, the maize of higher moisture content has faster respiration rate at the same temperature, for the same moisture content of maize, higher respiration rate has been observed in higher temperature. The maize at 15℃ showed changes in respiration rate： low moisture 0. 047-0. 431 mL . g . d^-1, safe moisture 0.059-0. 574 mL .g. d^-1 and high moisture 0.071 -0. 707 mL . g . d^-1 ;the maize at 20℃ ex- hibited changes in respiration rate： low moisture 0. 143 -0. 520mL. g. d^-1, safe moisture 0. 183 -0. 734 mL. g . d^-1 and high moisture 0. 173 -0. 707 mL . g .d^-1 ; the maize at 25℃ exhibited changes in respi- ration rate： low moisture 0. 199-0. 910mL . g . d^-1, safe moisture 0. 192-1. 170 mL . g . d^-1 and high moisture 0. 241-1. 197 mL . g. d^-1 ; the maize at 30℃ showed changes in respiration rate： low moisture 0. 194-1. 360 mL .g . d^-1, safe moisture 0. 203 -1. 541 mL . g. d^-1 and high moisture 0. 256 -1. 964 mL . g . d^-1. The respiration rate of maize having the same moisture contents decreases with reducing ox- ygen concentration. The study was undertaken to perform regression analysis according to trends of maize respiration rate due to changes in time and oxygen concentration and to obtain the regression equations of respiration rate of maize with different moisture contents in different temperature conditions. On the basis of correspond- ing regression equations obtained, the prediction model can be employed to work out the respiration rate of stored maize under hermetic condition in terms of different time and oxygen concentration and to provide basic parameters for rational utilization of maize respiration under controlled atmosphere storage environ- ment.