荒漠碱土代换性钠对小麦苗期生长的影响

Effects of Exchangeable Sodium on the seedling Stage of Wheat in Deset Alkali Soil

研究土壤碱化对不同农作物生长的影响是碱化土壤改良十分重要的课题,国内外对此已作了许多工作。其研究内容大多为以不同品种的耐碱性能,作物对矿质养分的吸收及在不同碱化程度土壤上作物的生长等。本文选择北疆主要农作物冬小麦,研究了在不同代换性钠百分率条件下,小麦苗期的生长情况,探索了其生长不良之原因。

A desert sierozen, collected from Shihezi area of Xinjiang,was treated bya series of chemical and physical methods to make several soil specimens withdifferent ESP value from each other.The soil specimens were made use itostudy effects of exchangeable sodium on the germination, emergence and seedl- ng growth of winter wheat by potted cultivation experiments and laboratoryanalysis.The results shown that higher content of exchangeable sodium insoil has intenser inhibition for germination, rate of emergence and growth ofseedling stage. When ESP over 18%, the inhibition displied certain symptomsclearly: slow germination, low rate of emergence, weak growing, short andslim plant, crimpy leaves like a lacking water sign, roots getting yellow androottops becoming brown.When ESP over 50%, growth of wheat went tobad restraint even to die.The results, which were obtained by elements analysis in the wheat seed-ling, could consider as that the impediment of plant growth during earlyseedling in alkali soil is mainly due to difficulty in taking up mineral nutrit-ion and the ion competition of exchangeable sodium.Because of accumu-lating a number of sodium in seedling the contents of K, Ca, Mg woulddecrease relatively, so that to cause unbalances of mineral nutrition and torestrain wheat growth.