施锌对小麦开花后氮、磷、钾、锌积累和运转的影响

为明确大田条件下施锌对小麦地上部器官氮、磷、钾、锌的积累量和转移量的影响,2001～2002年开展了田间试验。试验以专用强筋小麦(8901-11)和普通小麦(4185)两个冬小麦品种为材料,包括4个施锌水平(分别为施ZnSO4.7H2O.0、11.25、22.5和33.75.kg/hm2)。结果表明,各器官中Zn的含量变化在4.14～54.18.mg/kg,刚开花时及灌浆前期的含量以子粒>穗壳>叶片>茎秆,至接近成熟时则以子粒>叶片>穗壳>茎秆。每生产100.kg小麦子粒需要吸收Zn的范围在4.40～5.20.g之间。小麦成熟时吸收的Zn约为N或K2O的1/800～1/700,为P2O5的1/500～1/300。施锌后小麦各器官氮、磷、钾、锌的积累量及开花后向子粒的运转量增加,但施锌过多,这些营养元素的吸收、积累和运转反而受到抑制。4185开花前吸收氮和磷的能力较强,而8901-11开花后吸收氮和磷的能力较强;而吸收钾和锌的能力与吸收氮和磷的情况相反。8901-11氮、磷、钾、锌的积累量基本随施锌量增加而提高,以施硫酸锌22.5～33.75.kg/hm2的积累量最高;而4185以施硫酸锌11.25.kg/hm2的积累量最高。因此,在施用大量元素的基础上,普通小麦以施硫酸锌11.25.kg/hm2为宜,而强筋小麦以施硫酸锌22.5～33.75.kg/hm2为宜。

Effect of zinc fertilization on accumulation and transportation of N, P, K and Zn after anthesis of wheat

In order to clarify the effect of zinc fertilization on the amounts of accumulation and transportation of N,P,K and Zn in above-ground organs of wheat,a field experiment with four zinc levels(ZnSO₄·7H₂O 0,11.25,22.5 and 33.75 kg/ha) was conducted on the Teaching and Demonstration Farm of Agricultural University of Hebei during 2001—2002.Two winter wheat cultivars 8901-11 and 4185 were used as experimental materials.The results showed that the concentration of Zn in various organs ranged from 4.14 to 54.18 mg/kg,with the order: grains >husks >leaves >stems at anthesis and early grain filling period,and the order of grains >leaves >husks >stems during late grain filling period.The amount of Zn required for 100 kg grain production ranged from 4.40 to 5.20 g.The accumulation of Zn at maturity was accounted for about 1/800—1/700 of N or K₂O,and about 1/500—1/300 of P₂O₅ respectively.Zinc(application) could enhance the accumulation of N,P,K and Zn in above-ground organs.And the transportation rate to grains also increased due to the increase of zinc fertilization.However,excess zinc fertilization could lower accumulation and transportation of these nutrients.Nutrient uptake and accumulation patterns were different for those tow cultivars,4185 had a stronger N and P uptake capacity before anthesis,while 8901-11 had a stronger uptake capacity on N and P after anthesis.The K and Zn uptake capacity of those two cultivars show a reversed pattern with that of N and P uptake before and after anthesis.The accumulation of N,P,K and Zn in 8901-11 went up with the increasing zinc fertilization.The highest accumulation was observed when the application rate of ZnSO₄·7H₂O was 22.5—33.75 kg/ha.The highest accumulation by 4185 was observed when the ZnSO₄·7H₂O application rate was 11.25 kg/ha.Therefore,we can conclude,with enough macro-element supply,the optimum rate of zinc fertilization was 11.25 kg/ha for the cultivar 4185,but 22.5—33.75 kg/ha for the cultivars 8901-11.