Recently, research on Ca2+ transport in plants has been focused on cellular andmolecular level. But the uptake, transport and distribution are also very important for calcium to accomplish its function at whole plant level. There are many cells along the way of transport of Ca2+ from root to shoot, and Ca2+ passes either through the cytoplasm of cells linked by plasmodesmata (the symplast) or through the spaces between cells (the apoplast), which include Ca2+ uptake by root cells, Ca2+ transport from root cortex to and through the xylem, and then out of it into leaves or fruits. Ca2+ channels, Ca2+/H+ antiporter and Ca2+-ATPase play roles in the uptake and transport of Ca2+ in root cells. To be transported fromroot surface to xylem, Ca2+ needs to traverse endodermal cells and xylem parenchyma cells. Endodermal Casparian band, the main barrier for the apoplastic movement of ions into the stele, compels some Ca2+ to enter root symplast through Ca2+ channels in endodermal cells and then reach xylem parenchyma. Ca2+-ATPasemay drive Ca2+ into the stelar apoplast from xylem parenchyma. Some Ca2+ effuses from endodermal cell and then get to xylem through apoplastic pathway. Ca2+ is transported in plant xylem vessel in chelate form and the speed of water flow is the key factor Ca2+ transport via xylem in trunk. There are both apoplastic and symplastic pathways of Ca2+ transport in fruit or leaf tissue too.

蛋白质的可逆磷酸化是细胞信号识别与转导的重要环节，蛋白激酶主要催化蛋白质的磷酸化作用。植物中已发现并分离了大量蛋白激酶及其基因，它们介导了植物激素和胞外环境信号等引起的多种生理生化反应。文章着重介绍分裂原激活蛋白激酶(MAPK) 、钙依赖而钙调素不依赖的蛋白激酶(CDPK) 、受体蛋白激酶(RPK) 、核糖体蛋白激酶和转录调控蛋白激酶等多种蛋白激酶在植物逆境信号识别与转导中的作用。

The uptake rate of Ca2+ and Ca2+-ATPase ultracytochemical localization were studied using Malus hupenensis Rehd seedlings and pot-cultured two-year-old apple trees (‘Starkrimson’/Malus hupenensis Rehd), after treatment with IBA. The results showed, IBA increased activity of roots and Ca2+-ATPase and rate of Ca2+ uptake. But Ca2+ uptake rates were inhibited by 2,4-DNP, the metabolic inhibitor, and the inhibition degree was higher under low Ca2+ concentrations (0 ～0.5 mmol/L) than high Ca2+ concentrations (0.5～5 mmol/L). The Km and Imax and the ratio (Imax/Km) all increased, and the inhibition degrees were higher in excised root than intact roots after roots were treated with IBA. The Imax and a (Imax/Km) increased but the Km after spraying IBA on leaves. 2,4-DNP inhibited the effects of IBA on Ca2+ absorption. Ca2+-ATPase was located on the cytoplasmic membrane and the vacuolar membrane. The activity of Ca2+-ATPase on the cytoplasmic membrane was increased significantly after treating by IBA.

就果树根系对地上部的调控、根源信使的确认及其对水分利用效率(WUE)的调节等方面进行了评述，并在此基础上提出了调整根系在上下层土壤中的分配比例、改善根冠平衡、实施隔行交替灌溉等提高果树WUE的技术设想。

越冬期苹果根系氨基酸总量和蛋白酶活性在12-1月保持低水平，2月份开始回升，3-4月增幅最大；冬季地膜覆盖提高了根系蛋白酶活性和氨基酸含量，初冬和初春效果最明显。氨基酸总量，细根高于粗根;蛋白酶活性，初春粗根高于细根;蛋白质含量于1月份出现高峰，3月以前粗根高于细根;覆膜对蛋白质含量影响不明显。冬春根中含多种氨基酸，但以天门冬氨酸、谷氨酸、脯氨酸和精氨酸为主;越冬之后粗根中有3种氨基酸(Asp、Glu、Arg)含量增加，细根中有13种氨基酸(Asp、Glu、Thr、Ser、Gly、Ala、Val、Ile、Leu、Tyr、Phe、Lys、His)含量增加;两种根内脯氨酸含量均是冬季大于春季。