论文部分内容阅读
于2011年在黄土高原半干旱地区以平地不覆膜为对照,研究了不同沟垄和覆膜方式对马铃薯叶片和土壤水势水势的影响。结果表明:不同沟垄和覆膜方式在不同土层和不同生育期对土壤和叶片水势的影响差异显著。(1)土壤水势日变化趋势:0~20cm土层,土垄处理在开花期为先下降后上升型,土垄和覆膜垄处理在块茎膨大期为先下降后上升型,覆膜垄和全膜双垄沟播处理在成熟期为先下降后上升型,其余为逐渐下降型;20~40cm土层,各处理土壤水势呈逐渐下降趋势。(2)叶片水势日变化趋势:开花期和块茎膨大期表现为双低谷型,双低谷分别在13:00和17:00,成熟期为“V”型,即单低谷型,低谷出现在17:00。各处理变化趋势相同,但水势存在差异。土垄处理在水分关键期(开花期和块茎膨大期)叶片水势显著高于其他处理,而全膜双垄沟播处理在成熟期最高。(3)生育期土壤水势和叶片水势均表现为先减小后增大的趋势。20~40cm土层对叶片水势影响较大,土垄处理在该土层具有较好的水分状态,蒸腾作用较强加速了水分运移速率,是导致覆膜垄和全膜双垄沟播处理水势低于土垄的主要原因。在前期降雨较少的年份,由于较小的蒸腾作用,土垄处理可以保证马铃薯承受较小的水分胁迫;在前期降雨量较多的年份,覆膜垄和全膜双垄沟播处理则可以凭借其较大的蒸腾作用发挥较大的增产效果。
In 2011, in the semi-arid area of the Loess Plateau, the effects of different furrow-ridge and film-mulching methods on the water potential of potato leaves and soil were studied. The results showed that there were significant differences in soil and leaf water potential between different ridge and film mulching patterns in different soil layers and different growth stages. (1) The diurnal variation trend of soil water potential: In 0 ~ 20cm soil layer, the soil ridge treatment firstly descended and then risen in the flowering stage. The ridge ridge and the laminating ridge treatment firstly decreased and then rose, In the mature stage, the furrow sowing of double-ridged furrows first decreased and then rose, while the rest decreased gradually. In 20 ~ 40cm soil layer, the soil water potential decreased gradually. (2) The diurnal variation trend of leaf water potential: the double-trough type appeared at the flowering stage and the bulky tuberosity stage, the double trough was at 13:00 and 17:00 respectively, and the mature stage was the “V” type, ie the single trough type and the low trough appeared At 17:00. The treatment trends are the same, but the water potential is different. The ridge water potential of ridge treatment was significantly higher than that of other treatments at the critical period of water (flowering stage and bulking stage of tubers), while the furrow sowing treatment with full film double layer was the highest at maturity stage. (3) Soil water potential and leaf water potential in growing period showed the trend of decreasing and then increasing. Soil layer of 20 ~ 40cm had greater influence on leaf water potential, soil ridge treatment had better water status in this soil layer, strong transpiration accelerated the rate of water transport, which was the result of water treatment potential Lower than the main reason for the ridge. Due to the small transpiration, the ridge treatment can ensure the potato to withstand less water stress in the earlier period of rainfall. In the earlier period of rainfall, Its larger transpiration play a greater yield-increasing effect.