不同覆膜对制种油菜生长及土壤水热的影响

为了给发展制种油菜节水高效栽培技术提供理论依据,采用随机区组试验设计,研究了不同覆膜栽培模式对制种油菜土壤水热变化动态、生育进程及产量的影响。试验设5个处理分别为:半膜平作(FHP)、半膜垄作(RHP)、全膜平作(FOP)、全膜垄作(ROP)和不覆膜平作(CK),从制种油菜生长发育动态,土壤水热变化规律,产量及水分利用效率等方面比较了不同栽培技术的优越性。结果表明,全生育期FHP、RHP、FOP和ROP处理0~25 cm土层土壤积温分别较CK增加97.4、132.3、196.7和257.6℃(P0.05),且有效延长了制种油菜花期,FOP、ROP、FHP和RHP处理花期分别较CK延长16、13、11、9 d;覆膜栽培可有效地改善制种油菜田0~110 cm土壤水分状况,且以0~30 cm表现最为显著,随着土层深度的增加,其影响效果逐渐减弱;FHP、RHP、FOP和ROP处理均促进了植株个体发育,提高了制种油菜单株角果数、角粒数、制种产量和水分利用效率,其中以ROP处理最为显著,制种产量较CK增加34.05%,水分利用效率较CK提高30.83%。由此可见,全膜垄作栽培可推荐为春油菜制种较为理想的节水高效栽培模式。

Impact of Plastic-film Mulching on Dynamics of Soil Water,Temperature and Growth of Rape Seedlings

This paper investigated experimentally the dynamics of soil water and temperature, as well as the de-velopment and seedling-yield of rape in attempts to improve water use efficiency and provide agronomical meth-od to sustain rape production. Five treatments were examined: flat planting with half mulched by plastic film (FHP), ridge planting with half mulched by plastic film(RHP), flat planting with complete plastic-film mulching (FOP), ridge planting with complete plastic-film mulching. The control is flat planting withoutmulching. The re-sults showed that there was a significant increase in soil temperature (0～25 cm layer) in all treatments with mulch-ing. Compared with the CK, the accumulated soil temperature under FHP, RHP, FOP and ROP increased by 97.4, 132.3, 196.7 and 257.6℃(P<0.05) respectively. Mulching prolonged the florescence of the rape seedling, increas-ing by 16, 13, 11, 9 d under RHP, ROP, FHP and FOP respectively compared with the CK. Mulching also in-creased soil water in 0～110 cm depth, especially in the top 0～30 cm. In both flat and ridge plantings, mulching promoted the growth of individual plant, as well as its pod number, grain number per pod, yield and water use ef-ficiency(WUE). Compared with other treatments, ROP is most efficient in increasing yield and WUE, and can serve as an agronomical model for cultivation of spring rape seedling.