根系分區交替灌溉與調缺灌溉對‘玉女’小果番茄果實產量與品質之影響

Abstract

小果番茄栽培過程中需要消耗大量水分，在臺灣西半部雨量分配不均、缺水嚴重的影響下，節水灌溉的使用將會越加頻繁。根系分區交替灌溉(partial root-zoon irrigation, PRI)或稱Partial root-zone drying irrigation (PRD)是一特別的節水灌溉方法，透過根系分區、乾濕交替，誘發植物內部產生逆境，使氣孔關閉，減少水分散失，但能夠維持光合作用並促使次生根生長。PRD處理後的番茄植株，表現出水分利用效率提升，果實品質提高等有利於作物栽培的特性。本研究以農友種苗股份有限公司之‘玉女’小番茄作為試驗材料，期望找出最適合生產‘玉女’小番茄的根系分區交替灌溉方法與水分含量，達到提高水分利用效率、維持或提升果實品質效果。試驗一結果顯示2017年秋季栽培番茄於開花期開始進行PRD處理能夠有效增加果實總抗壞血酸含量達309 mg·L-1、總可溶性固形物含量達9.09 oBrix，且提高水分利用效率及維持產量，說明PRD處理對‘玉女’小番茄是有提高果實品質且維持產量的效果。試驗二結果顯示2018年春季栽培番茄於果實綠熟期開始進行PRD處理能夠提高果實單果重並同時維持產量及果實品質。試驗三結果顯示2018年秋季栽培番茄於開花期開始進行PRD處理，在多數測量項目中表現最佳，特別是擁有最高的總可溶性固形物含量，可達到11.64 oBrix。綜合上述試驗結果，‘玉女’小番茄可以透過PRD處理達到維持果實產量、提高果實品質且減少灌溉用水，而春季推薦綠熟期開始進行PRD處理，秋季則建議開花期開始進行PRD處理。

Cherry tomato needs to consume a lot of water during cultivation. Because of the uneven rainfall distribution and water shortage in western side of Taiwan, water-saving irrigation will be used more frequently. Partial root-zone irrigation (PRI) or partial root-zone drying irrigation (PRD) is a special deficit irrigation method, through root-zone dividing and dry-wet alternating to induces internal stress in the plant, so that the stomatal closure reduces water loss, but still maintain photosynthesis and promote secondary root growth. The tomato plants treated with PRD showed improved water use efficiency (WUE) and improved fruit quality, which were beneficial to crop cultivation. This research used cherry tomato ‘Rosada’ from Known-You Seed Co., Ltd as material, and hopes to find the method and water content of PRD which is most suitable for production of ‘Rosada’ tomato to improve WUE and maintain or enhance the fruit quality. The results in experiment I showed that tomato plants cultivated in the fall of 2017 treated with PRD start at the flowering stage could effectively improve the fruit total ascorbic acid content to 309 mg·L-1, fruit total soluble solid content to 9.09 oBrix and enhance WUE and maintain fruit yield, indicating that PRD treatment has the effect of improving fruit quality and maintaining yield for cherry tomato ‘Rosada’. The results in experiment II showed that tomato plants cultivated in the spring of 2018 treated with PRD beginning from the mature green stage of fruit can increase single fruit weight while maintaining the yield and fruit quality. The results in experiment III showed that tomato plants cultivated in the fall of 2018 treated with PRD start at the flowering stage performed best in most of the measurement items, especially with the highest total soluble solid content. It reached 11.64 oBrix. Based on the above results, cherry tomato ‘Rosada’ can maintain fruit yield, improve fruit quality and reduce irrigation water through PRD treatment. In spring, it is recommended to start PRD treatment from mature green stage of fruit. In fall, it is recommended to start PRD treatment from flowering period.