嫁接與調缺灌溉對‘玉女’小果番茄果實產量及品質之影響

Effects of Grafting and Regulated Deficit Irrigation on Fruit Yield and Quality of Cherry Tomato‘Rosada’

有鑑於臺灣水資源短缺情況日益嚴重，發展作物節水灌溉栽培為當務之急。許多研究表明節水灌溉可提高番茄果實品質並維持產量，惟節水成效因作物種類、環境因子、施用時機等之不同而時有差異。‘玉女’小果番茄在臺灣常以嫁接方式進行栽培，本試驗目的為探討嫁接之影響並建立‘玉女’小果番茄最適灌溉模式。春夏季試驗栽培結果呈現，嫁接處理可提高果實總可溶性固形物及抗壞血酸含量，果皮呈色方面為Hue angle值、b*值及彩度較低，其餘項目與非嫁接對照組並無顯著差異。相較於全量灌溉對照組(full irrigation, FI,介質體積含水量維持在44%)，使用嫁接苗於果實綠熟期施用調缺灌溉處理將介質體積含水量維持在22%可節省約56%用水量，提高水分利用效率、維持產量並具備與對照組相似之果實品質，僅a*值較高。本研究結果顯示，節水灌溉成效因嫁接與灌溉方法而異。相對於實生苗，使用嫁接苗進行栽培可提高耐旱性及獲得較佳果實品質，故建議春夏季栽培可使用嫁接苗並於果實綠熟期進行22%調缺灌溉，可提高水分利用效率並維持果實產量及品質。

Concerning the raising shortage of water resources in Taiwan, the development of crop deficit irrigation (DI) is a priority. Many studies had revealed that DI could improve tomato fruit quality and maintain yield, but the water-saving effect varied with crops, environmental factors, and application timing etc. Cherry tomato‘Rosada’is often cultivated by using grafted seedlings in Taiwan. The objective of this research was to investigate the effect of grafting and establish the optimal irrigation mode for‘Rosada’cherry tomato. The results of spring and summer experiments showed that grafting treatment could increase the total soluble solids and ascorbic acid content in the fruit, while the Hue angle value, b* value and chroma value of the pericarp were lower. However, there was no significant difference exhibited in other investigated traits between grafted and non-grafted seedlings. In comparison with the full irrigation control group (FI, medium volumetric water content (VWC) maintained at 44%), grafted plants subjected to RDI to maintain VWC at 22% at the mature green fruit stage could save about 56% of water with increased water use efficiency (WUE), and produced similar fruit yield and quality only with higher a* value. This study showed that the effectiveness of RDI varied with grafting and irrigation methods. The use of grafted cherry tomato seedlings, instead of the non-grafted seedlings for cultivation could improve drought tolerance and obtain better fruit quality. Therefore, it is recommended to use grafted seedlings for spring and summer cultivation and with 22% RDI at mature green fruit stage to improve WUE and maintain fruit quality and yield.