摘要
The grain yield variation among 18 maize crosses with the upright,medium and patulous plant type in the close,middle and thin densities was studied in Heiongjinag province.The upright crosses with leaf orientation value more than 45 and leaf length-width ration more than 7.5 showed adaptation to close planting,The higher leaf orientation value and leaf length-width ratio of up-right crosses would play their parts to yield independently only in the close density in the test (95200 plants/ha).In the thin and middle density treatments the upright crosses yield no more than medium and patulous ones.
