摘要
水分胁迫对番茄幼苗的生长有严重的抑制作用。幼苗根、茎、叶干重及株高、茎粗、叶面积等形态指标同土壤水分张力(PF值)呈极显著负相关。幼苗叶片水势有明显的日变化,春季日变化呈三次曲线(S型)。叶片水势同土壤PF值呈极显著负相关。这是利用土壤PF值进行番茄苗期水分管理的依据。叶片相对含水量、水分饱和亏、自由水、束缚水含量,细胞汁液浓度也同土壤PF值显著相关。土壤水分亏缺增加,叶片净光合率下降,游离氨基酸含量升高,硝酸还原酶活力降低。根据本试验结果认为,番茄幼苗从分苗到定植,土壤PF值维持在1.9—2.2范围内,幼苗生长健壮。
The responses of tomato seedling to water stress using tensiometer were studied. The results showed that the growth of tomato seedling was inhibited seriously by water stress. The dry weights of root,stem, leaf were all significantly negative correlated with the value of PF,so did the plant height, stem diameter and leaf area. There are dramatic variety in leaf water potential(ψL). The curves ofψL diurnal variety were S pattern, ψL and PF were in significantly correlation, which is the base for using PF as an index to irrigate tomato plant during seedling stage. Relative water content ( RWC ) , Water saturation defi-cit ( WSD ) , free water, bound water and cell sap concentration were all correlated with PF.With the increase of soil water deficit. net photosynthesis ( Pn) decreased, but free amino acid content increased. NR activity is significantly correlated with PF.According to this studies,it is shown that tomato seedling grow well and strongly in the range of PF 1.9 to 2.2.
出处
《园艺学报》
CAS
CSCD
北大核心
1991年第4期340-344,共5页
Acta Horticulturae Sinica
关键词
番茄
幼苗
PF值
水分胁迫
Tomato seedling
Soil PF
Water stress
