Variation rule of EDTA-Na2 in grape shoots based on trellis and phenological period

Abstract To better understand the physiological processes involved in responses of trellises to the transportation and distribution of nutrient within shoots of grapevines, analysis method of disodium ethylenediamine tetraacetate (EDTA - Na 2 ) was employed at the whole development stages of vine. In the trial, the traditional independent long-stem pruning (ILSP) was taken as control to compare the effect of new single crawled cordon training (SCCT) on the transportation and distribution of phloem sap on the experimental material Ecolly. Thus the consumption level of phloem sap in the grapevine shoots of various trellises was analyzed by EDTA-Na 2 phloem sap exudation technique during the whole development. Results was that the consumption rate of EDTA - Na 2 solution in the SCCT and ILSP shoots increased before August 15 (15.130 g–16.216 g in SCCT and 10.653 g–15.042 g in ILSP, respectively) including 16.348–20.809 g in SCCT and 11.912–19.593 g in ILSP from August 25 to September 4 as well as decreased in August 15–25 (17.216–16.348 g in SCCT and 15.042–11.912 g in ILSP, respectively) and after September 4 (20.809–7.669 g in SCCT and 19.593–4.072 g in ILSP), respectively, and values of SCCT were always higher than that of ILSP during the whole growth. In addition, EDTA - Na 2 consumption content in the phloem sap per shoots in SCCT kept almost around 16 g, more than that in ILSP, from 21 July to 25 August. Therefore, SCCT was more advantageous to accumulate nutrient compared with ILSP, and ensured an even distribution of phloem sap in the grape shoots from berry growth to maturity.