Studies on nitrogen uptake and accumulation of cold type wheat Double adaptability of cold type wheat to drought and rainy weather Characteristics of flag leaf senescence and activated oxygen metabolism for cold type wheat Heat balance of cold type wheat field at grain-filling stage under drought stress condition Leaf senescence and active oxygen metabolism of different-type wheats under drought A study on the farmland heat distribution conditions of cold type wheat during milk-filling Analysis of the farmland microclimatic characteristics of cold type wheat during milk-filling Studies of phosphorus uptake and accumulation of cold type wheat