基于茎直径变化的甘蔗水分亏缺诊断指标确定  

Rational indicators for water deficiency diagnosis of sugarcane based on stem diameter variations

作　　者：陈海波[1,2] 李就好[3,2] 余长洪[3] 张连宽[4] 

机构地区：[1]华南农业大学工程学院,广州510642 [2]华南农业大学南方农业机械与装备关键技术教育部重点实验室,广州510642 [3]华南农业大学水利与土木工程学院,广州510642 [4]华南农业大学理学院,广州510642

出　　处：《农业工程学报》2014年第19期115-122,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：广东省科技计划项目(2008B030303034)

摘　　要：为了确定甘蔗水分亏缺诊断指标及其临界值，该文以新台糖22号为试验材料，通过盆栽和大田试验研究了水分胁迫下甘蔗全生育期植株茎直径变化特征，然后利用盆栽试验数据分析了盆栽甘蔗的茎直径变化指标日最大收缩量（maximum daily shrinkage，MDS）、日增长量（dailyincrease，DI）和土壤水分的关系，回归建立了基于MDS和DI的甘蔗水分亏缺诊断模型。大田和盆栽试验均表明，甘蔗处于苗期、分蘖期和伸长期的茎生长阶段，土壤水分差异导致的茎生长差异显著（P＜0.01）。盆栽试验表明60%以下田间持水率的水分胁迫（中度及重度干旱）在茎生长阶段均可使甘蔗茎直径增长总量降低约41.7%～100%，且对甘蔗茎直径增长的影响以伸长期最大，分蘖期次之，苗期最小；在甘蔗成熟期，16个观测日正常、轻、中和重旱茎直径总增长量分别为0.049、0.055、0.048和0.033mm，该阶段茎秆基本停止生长，土壤水分差异导致的茎生长差异不显著（P＞0.05），成熟期对水分亏缺最不敏感。对各生育期的MDS和DI与土壤含水率的回归分析结果表明，除成熟期DI指标外，其他各生育期的MDS和DI均与土壤含水率显著线性相关，决定系数在0.501～0.765之间。苗期MDS、分蘖期和伸长期的DI能更好地诊断水分亏缺。所建立的模型可较好的诊断甘蔗水分亏缺，研究结果可为利用茎直径变化指导甘蔗灌溉提供理论依据。In order to test the feasibility of diagnosing water deficiency of sugarcane using parameters related with stem diameter variations, both pot experiment and field experiment were conducted. In the pot experiment, pots were selected with 60 cm in length and width, and 40 cm in depth. Sugarcane t22 was planted in pots and field. Stem diameter variations were continuously measured. The diurnal variations of stem diameter at different growing stages under different water deficits were investigated, and maximum daily shrinkage （MDS） and daily increase （DI） were calculated based on relative variations （RV） of stem. In addition, the correlations between MDS, DI （from pot experiment） and soil moisture were analyzed. A water deficiency diagnosis model was established and assessed by the F test. The results showed that RV values were significantly （P〈0.01） different among different soil moisture treatments during the stem growing period include of seedling, tillering and elongating stage. The overall growth of sugarcane stem diameter was reduced by about 41.7% to 100% as soil moisture was less than 60% of field capacity. Elongating stage was most sensitive to soil moisture deficiency, followed by tillering stage and seedling stage. At the stem mature period （that was sugarcane’s mature stage）, the total amount of stem diameter growth （sugarcane planted in pots） was 0.049, 0.055, 0.048 and 0.033 mm in 16 observation days under conditions of normal irrigation, light drought, moderate drought and severe drought, respectively. The growth of stem diameter basically stopped at this stage and thus it was the least sensitive to water deficits. The regression analysis showed that MDS and DI were significantly correlated （P〈0.01） with soil water content at different growing stages of stem except for DI at mature stage, the coefficient of determination was 0.501-0.765. During the stem growing period include seedling, tillering and elongating stage, MDS and DI both had high response to water stres

关 键 词：土壤 水分 诊断 甘蔗 茎直径变化 日最大收缩量 日增长量 水分亏缺 

分 类 号：S274.4[农业科学—农业水土工程]