不同施肥处理对三倍体毛白杨苗木生长及抗寒性的影响

为研究施肥对三倍体毛白杨苗木生长和抗寒性的影响 ,采用不同施肥时期和不同施肥量处理苗木 ,结果表明 :在苗高生长结束后的秋季进行了一次性施肥 ,促进苗木对N ,P的被动吸收 ,提高了苗木的抗寒性 .既有速生前期施肥又有秋季施肥的处理 ,不仅提高了苗木的生长量 ,而且增强了苗木的抗寒性 .在室内应用相对电导率、失水率、水分饱和亏缺以及生长恢复试验对各施肥处理苗木的抗寒性进行了测定 .综合评定结果表明 ,各施肥处理在提高苗木抗寒力的作用方面大小顺序为 :秋季将肥料全部施入 >速生前期施 1/ 2 ,秋季施 1/ 2 >速生前期将肥料全部施入 >速生前期施 1/ 3 ,速生后期施 1/ 3 ,秋季施 1/ 3 >对照 (不施肥 ) >速生前期施 1/ 3 ,速生中期施 1/ 3 ,速生后期施 1/ 3 >速生前期施 1/ 2 ,速生后期施 1/ 2 .

Effects of fertilizer treatments on seedling growth and cold resistance of triploid Populus tomentosa

In order to study the effects of fertilizer treatments on seedling growth and cold resistance of triploid Populus tomentosa , seedlings were treated with different fertilizing time and regime. The results show that fertilizing in autumn after height growth stop can help seedlings absorb N and P and increase cold resistance. Fertilizing in both early fast growing period and autumn can not only enhance seedling growth but also increase cold resistance. After evaluating by an integrated indicator, combined from relative electric conductivity, rate of water loss, water saturation deficit, and growth recover test, the sequence of effects of fertilizing treatments on seedling cold resistance is as follows: applying total fertilizer in autumn >applying 1/2 fertilizer in early fast growing period and 1/2 in autumn >applying total fertilizer in early fast growing period >applying 1/3 in early fast growing period , 1/3 in later fast growing period, 1/3 in autumn>control (no fertilizer)>applying 1/3 in early fast growing period, 1/3 in middle fast growing period, 1/3 in later fast growing period> applying 1/2 in early fast growing period , 1/2 in later fast growing period.