草业学报
草業學報
초업학보
PRATACULTURAL SCIENCE
2015年
6期
53-63
,共11页
紫花苜蓿%NO3--N%NH4 +-N%生育期%根系特性
紫花苜蓿%NO3--N%NH4 +-N%生育期%根繫特性
자화목숙%NO3--N%NH4 +-N%생육기%근계특성
Alfalfa (Medicago sativa )%nitrate nitrogen%ammonium nitrogen%growing%root characteristics
在完全营养液的条件下，采用砂培法，研究了3种外源氮素形态配比（NO3－-N，NH4＋-N 以及 NO3－-N∶NH4＋-N 为1∶1）和3个氮素水平（0，105，210 mg／L）对“甘农3号”紫花苜蓿整个生育期根系特性的影响。结果表明，不同形态氮素处理下紫花苜蓿的根系生物量、根表面积、根体积、根系活力、根瘤数、根瘤重和固氮酶活性均显著高于 CK，NO3－-N 和 NH4＋-N 混合培养下效果最好，NH4＋-N 培养下次之，NO3－-N 培养下最低，但对根系平均直径的影响并不大。随着氮素水平的增加，各形态配比下紫花苜蓿的根系生物量、根表面积、根体积、根系活力、根瘤数、根瘤重和固氮酶活性均呈增加的变化趋势，各指标在 NO3－-N＋NH4＋-N 的浓度为210 mg／L 时，达到最大值。整个生育期，各处理下紫花苜蓿的根系生物量、根表面积、根系活力、根瘤数、根瘤重和固氮酶活性均在苗期、现蕾期、盛花期差异比较明显，结荚期和鼓粒期差异不显著，各指标之间均有不同程度的相关性。
在完全營養液的條件下，採用砂培法，研究瞭3種外源氮素形態配比（NO3－-N，NH4＋-N 以及 NO3－-N∶NH4＋-N 為1∶1）和3箇氮素水平（0，105，210 mg／L）對“甘農3號”紫花苜蓿整箇生育期根繫特性的影響。結果錶明，不同形態氮素處理下紫花苜蓿的根繫生物量、根錶麵積、根體積、根繫活力、根瘤數、根瘤重和固氮酶活性均顯著高于 CK，NO3－-N 和 NH4＋-N 混閤培養下效果最好，NH4＋-N 培養下次之，NO3－-N 培養下最低，但對根繫平均直徑的影響併不大。隨著氮素水平的增加，各形態配比下紫花苜蓿的根繫生物量、根錶麵積、根體積、根繫活力、根瘤數、根瘤重和固氮酶活性均呈增加的變化趨勢，各指標在 NO3－-N＋NH4＋-N 的濃度為210 mg／L 時，達到最大值。整箇生育期，各處理下紫花苜蓿的根繫生物量、根錶麵積、根繫活力、根瘤數、根瘤重和固氮酶活性均在苗期、現蕾期、盛花期差異比較明顯，結莢期和鼓粒期差異不顯著，各指標之間均有不同程度的相關性。
재완전영양액적조건하，채용사배법，연구료3충외원담소형태배비（NO3－-N，NH4＋-N 이급 NO3－-N∶NH4＋-N 위1∶1）화3개담소수평（0，105，210 mg／L）대“감농3호”자화목숙정개생육기근계특성적영향。결과표명，불동형태담소처리하자화목숙적근계생물량、근표면적、근체적、근계활력、근류수、근류중화고담매활성균현저고우 CK，NO3－-N 화 NH4＋-N 혼합배양하효과최호，NH4＋-N 배양하차지，NO3－-N 배양하최저，단대근계평균직경적영향병불대。수착담소수평적증가，각형태배비하자화목숙적근계생물량、근표면적、근체적、근계활력、근류수、근류중화고담매활성균정증가적변화추세，각지표재 NO3－-N＋NH4＋-N 적농도위210 mg／L 시，체도최대치。정개생육기，각처리하자화목숙적근계생물량、근표면적、근계활력、근류수、근류중화고담매활성균재묘기、현뢰기、성화기차이비교명현，결협기화고립기차이불현저，각지표지간균유불동정도적상관성。
This paper reports research on the effect of exogenous nitrogen on the root characteristics of “Gan-nong No.3”Alfalfa at different growth stages.Samples were cultivated for the whole growth period using the sand culture method under the condition of complete nutrient solution.Three exogenous nitrogen forms (ni-trate nitrogen,ammonium nitrogen and nitrate nitrogen)were investigated;with the ammonium nitrogen solu-tion at 1∶1 and the others are three solution levels (CK,105,210 mg/L).Results showed that under different forms of nitrogen treatment,the root biomass,root surface area,root volume,root activity,root nodule num-ber,nodule weight,and nitrogenase activity of alfalfa are significantly higher than that of CK.With increasing nitrogen levels,there were increases in the proportions of alfalfa root biomass,root surface area,root volume, root activity,root nodule number,nodule weight and nitrogenase activity.The effects are in the following or-der:NO3 --N and NH4 +-N mixed culture the highest,followed by NH4 +-N and with NO3 --N the lowest. The impact on root average diameter was not large.The maximum values were reached by NO3 - +NH4 + with a concentration of 210 mg/L.In terms of the whole growth stage,root biomass,root surface area,root activi-ty,root nodule number,nodule weight and nitrogenase activity were significantly different during the seedling, budding and flowering stages.However,differences during seed podding and podding were not significant.
