旧膜再利用方式对旱地胡麻干物质生产及水分利用效率的影响

Effects of used plastic film disposal patterns on dry matter production and water use efficiency of oil flax in arid areas

为寻求地膜覆盖后旧膜再次利用的有效方式,探讨旧膜再利用后旱地胡麻的增产机理,在大田环境下,比较了旧膜直播(T1)、旧膜覆土直播(T2)、旧膜秸秆双重覆盖播种(T3)、春天揭旧膜覆新膜播种(T4)、秋后整地覆新膜春天播种(T5)及露地播种(T6,CK)6种处理方式对旱地胡麻生育进程中土壤水分、叶面积、干物质积累与分配、籽粒产量及水分利用效率的影响。结果表明:全地膜覆盖作物收获后旧膜继续留至翌年,仍具有一定的保墒和增温效应,光合面积和光合同化产物的积累量增加。不同旧膜再利用方式的保墒效果主要表现在胡麻现蕾期前,保证了胡麻全苗、壮苗,叶面积对旧膜再利用方式的响应基本与之一致,各处理均高于CK,且以T4处理均在枞形期及现蕾期效果最优,而开花期以T5处理居高。干物质积累量在生育前期T4处理较高,而生育后期T5处理居高。T4和T5处理成熟期干物质积累量、籽粒干物质分配量和分配比例及花后干物质同化量对籽粒的贡献率均高于CK,降低了干物质在主茎+分枝+果壳中的分配比例,T1、T2、T3介于T4和T5之间。籽粒产量各处理均显著高于CK,T4最高,达1 509.52 kg.hm 2,其余依次为T5、T1、T2、T3和T6,分别为1 370.77 kg.hm 2、1 171.84 kg.hm 2、1 158.47 kg.hm 2、1 011.36 kg.hm 2和620.52 kg.hm 2;水分利用效率与产量变化趋势基本一致,相应各处理分别比CK增加153.63%(T4)、129.82%(T5)、97.49%(T1)、85.71%(T2)和64.41%(T3)。说明春天揭旧膜覆新膜播种方式是兼顾保水高产的最优胡麻耕作方式,适宜在旱作农业区推广应用。

Field experiments were conducted to investigate how disposal patterns of used plastic films in field and mechanism of oil flax production enhance in arid areas.The study compared the influences of 6 used plastic film disposal patterns on oil flax soil water amount,leaf area,dry matter accumulation and distribution,water use efficiency and yield.The 6 patterns included field-kept film and no-tillage sowing the next year（T1）;field-kept film,earth mulching and no-tillage sowing the next year（T2）;field-kept film,straw mulching the current year and no-tillage sowing after straw clearing the next year（T3）;field-kept film replaced with new plastic film and no-tillage sowing the next year（T4）;film collection,land preparation,new plastic film mulching just after harvest and sowing the next year（T5）;and collected just after crop harvest,land reparation and no-mulch sowing the next year（T6,control）.The results showed that keeping used plastic films in fields till the next year had the same film mulch effect on soil moisture and temperature,thereby promoting photosynthetic area and favoring assimilation product accumulation.Soil moisture conservation effect under different disposal patterns of used films was strong before budding stage,ensuring the full and sound flax seedling growth.Leaf area response to the treatments had the same trend as soil water storage.Leaf areas in the five treatments were higher than in the control before budding stage.Treatment T4 was the best at momi fir pattern stage and budding stage,but T5 was the best at flowering stage.Accumulated amount of dry matter,amount and distribution proportion of dry matter,contribution of dry matter assimilation amount after anthesis to grain under T4 and T5 were higher than T6（CK）.And dry matter proportions in stem,spike axis and kernel husk also decreased.Also the values of these variables under T1,T2 and T3 were between those for T4 and T5.Yield of T1 to T5 treatments were significantly higher than T6,treatment T4 had the highest grain yield（1 509.52 kg.hm 2） with T5,T1,T2,T3 and T6 yields of 1 370.77 kg.hm 2,1 171.84 kg.hm 2,1 158.47 kg.hm 2,1 011.36 kg.hm 2 and 620.52 kg.hm 2,respectively.The trend in water use efficiency was the same as that in yield,which increased respectively by 153.63%（T4）,129.82%（T5）,97.49%（T1）,85.71%（T2） and 64.41%（T3） over CK.Therefore the study recommended T4 as the most appropriate tillage practice in high-yield and water-saving oil flax production.However,optimal reuse pattern of used plastic film also needed considerations of local soil physical conditions and disposal method selection.