EFFECTS OF PLASTIC FILM MULCHING ON GROWTH AND PHOTOSYNTHETIC AND PHYSIOLOGICAL PARAMETERS OF CORN RECEIVING DIFFERENT FERTILIZERS AT SEEDLING STAGE

In order to investigate the effects of plastic film mulching(PFM) on corn,the effects of PFM were studied in the present paper on the growth and photosynthetic parameters of corn receiving different fertilizers at seedling stage in the field condition.The results were presented as follows:(1) The effects of PFM on corn growth depended on the fertilization.Without the presence of PFM,the dry weight of corn plant was significantly increased by the NPK treatment,however,no effect of other fertilizer treatments was observed on dry weight of corn plant.PFM could significantly increase the dry weight by 27.85 ～ 126.3% .The strongest effect of PFM was observed on the growth of corn,which receives the phosphorus fertilizer along,with the increase of dry weight by 126.3% .The weakest effect of PFM was observed on the growth of corn,which receives the nitrogen,phosphorus,and potassium fertilizers together,with the increase of dry weight of corn plant only by 27.8% .(2) Effects of PFM on photosynthetic and physiological parameters also atributed to fertilization.PFM treatments could obviously inprove transpiration rate(Tr),and had no significant effects on stomatal limitation value(Ls ) of leaves of corn receiving different fertilizers.PFM could significantly enhance photosynthetic rate(Pn),stomatal conductance(Gs) of leaves of corn in the treatments of CK,N,and P,could also significantly increase the water use efficiency(WUE) of leaves of corn in the treatments of N,and P,with no significant effects on these parameters of leaves of corn in other treatments.For example,PFM increased the photosynthetic rates of leaves of corn by 89.2% 、49.2% and 28.1% ,respectively,in the treatments of CK,N,and P,compared to the corresponding treatments without PFM.All these results indicated that the conditions of nutrients in soils and fertilization should be considered when PFM were used in corn production in Northeastern China.