基于茎直径微变化的梨枣灌溉指标的初步研究

 研究了4年生酸枣砧梨枣（Ziziphus jujuba Mill.）植株主干茎直径微变化指标对土壤水势（SWP）变化的响应规律，以及与气象要素的关系。结果表明：土壤水势降低引起茎直径日最大收缩量（MDS）增大，日生长量（DG）、生长速率（TGR）和日最大值（MXTD）降低。在水分亏缺发展阶段和水分亏缺维持阶段，MDS和TGR的噪声信号（变异系数）较小，信号强度与噪声信号的比值较大，表明其对土壤水势变化反映敏感。此外，MDS、TGR与潜在蒸散量（ET₀）、正午水汽压亏缺（VPD_md）等气象因子的相关性显著，均能反映大气的干旱程度，因此TGR和MDS可作为梨枣水分亏缺的诊断指标。

Rational Indicators for Irrigation Scheduling of Pear-jujube Based on Microchanges of Stem Diameter

In the present paper,nine 2n–1 = 19 plants were obtained from the 534 microspore plantlets of autotetraploid Chinese cabbage by chromosome number examination , and then three monosomic lines(mono-3,mono-5 and mono-6)were preliminary identified by karyotype analysis and propagation in vitro. The plant and flower bud morphological characters,pollen viability and regularity were significantly different between the three monosomics and diploid. Flower bud type among the three monosomics also occurred markedly difference. The unitary chromosome of the monosomics was mainly existed in an univalent,occasionally formed a trivalent with another pair of homological chromosomes at diakinesis or at metaphaseⅠ,and the chromosome distribution of the monosomics was mainly 9-10 at anaphaseⅠ.