不同灌溉方式下生菜根系生长模型研究

为探明不同栽培方式对蔬菜根系生长的影响,采用滴灌、微喷灌2种灌溉方式和醋糟与草炭复配而成的4种栽培基质对生菜根长、根深和根区半径进行了试验研究。结果显示:不同灌溉方式下可用同一个预测模型;相同灌溉方式下,不同基质栽培生菜根系特征值差异不显著(P0.05),可用同一组模型参数来表示。以试验数据为基础,采用有效积温作为定量发育进程的尺度,构建了预测生菜根长和根深的动态生长模型;以根深和有效积温为自变量,建立了根区半径动态变化模型。运用重复试验数据对所建模型进行验证,滴灌和微喷灌生菜的根长、根深和根区半径的预测值与实际值之间回归估计标准误差和相对误差最大分别为290 cm、0.81 cm、0.63 cm和15%、12%、13%,表明所建立的3个动态变化模型具有较高的预测精度,可为节水型设施基质栽培生菜提供理论依据和决策支持。

Root Growth Model of Lettuce under Different Cultivation Substrates and Irrigation Modes

To find out the effect of cultivation methods on vegetable root, the lettuce root length, root depth and root width radius were studied in four cultivation substrates under drip and micro-sprinkler irrigation. The result indicated that root characters of lettuce cultivated in different substrates were no significantly different at 0.05 among different irrigation methods. Based on the experimental data of lettuce root, the simulation models for lettuce root length and root depth were established using the scale of effective cumulative temperatures (DD). The root depth in different layers and DD were used as the dependent variables to establish the root width radius model. The repeat test data were employed to verify the establishing models. The root mean square error and relative error between simulated and observed values were only 290cm, 0.81cm, 0.63cm and 15%, 12%, 13% for lettuce root length, root depth and root width radius under drip irrigation and micro-sprinkler irrigation.