摘要
采用土培盆栽方法模拟研究了玉米／花生、小麦／花生间作对花生铁营养状况的影响及其作用机制。结果表明，禾本科作物与花生间作对花生的铁营养状况有显著影响：当花生与玉米或小麦分别间作时，花生新叶叶色正常，而花生单作则表现出严重的缺铁黄化现象，间作花生新叶活性铁、叶绿素含量明显高于单作，两种间作花生各部位铁含量和吸收量明显高于单作，间作明显地促进了铁向花生地上部的转移；在单作花生表现缺铁症状１４ｄ的时间范围内，其根系质外体铁含量仅是间作花生的５２％～８０％；而根系还原力则是单作花生在表现缺铁症状后迅速提高，至缺铁第６ｄ时还原力达到最大值，随后花生根系还原力迅速下降，而间作花生在０～１４ｄ内还原力增加速度缓慢，在１０～１４ｄ中其根系还原力明显地高于单作花生根系还原力。其主要原因可能是禾本科作物玉米、小麦根系分泌物（如：麦根酸类植物铁载体）螯合土壤中难溶性铁并被花生吸收利用。
A soil culture experiment was carried out to test the effects of peanut maize or peanut wheat intercropping on iron nutrition of peanut.The results showed that intercropping improved iron nutrition of peanut significantly.If peanut was intercropped with maize or wheat,the young leaves of peanut had no iron deficiency symptom,but peanut plants in monocropping showed severe iron deficiency chlorosis on young leaves.For intercropping peanut,the active Fe content and chlorophyll content of young leaves were about two times of that of monocropping plants.The two kinds of intercropping not only increased iron concentration of different organs of peanut and iron uptake of peanut,but also promoted iron translocation from the root to the shoot.The Fe accumulation in root apoplast of monocropping peanut plants was only 52%～80% of that in peanut plants intercropped with maize or wheat.At the beginning of iron deficiency,the root Fe(Ⅲ) reducing capacity of monocropping peanut increased dramatically and reached its maximum in 6 days,after then,it decreased quickly.But root Fe(Ⅲ) reducing capacity of peanut intercropped with maize or wheat maintained high for a long time.The possible mechenism of it is that root exudation(phytosiderophores) from wheat or maize could maintain the Fe pools in the root apoplast and higher root Fe(Ⅲ) reducing capacity of peanut in intercropping systems.
出处
《生态学报》
CAS
CSCD
北大核心
1998年第5期489-495,共7页
Acta Ecologica Sinica
基金
国家自然科学基金
国家教委博士点基金
关键词
单作
间作
花生
铁营养
玉米
小麦
根系分泌物
monocropping,intercropping,iron nutrition of peanut,maize,wheat,root exudate(photosiderophores).
