不同灌溉水溫對番茄苗生育之影響

Abstract

本研究以'花蓮亞蔬五號'番茄為材料，調查不同水溫、植株部位、冷水灌溉時間對番茄苗矮化效果及其品質之影響，其目的為建立冷水灌溉矮化番茄苗之系統，以作為種苗產業之應用的參考依據，並作為深入研究矮化苗之基礎資訊。試驗結果顯示當灌溉水溫較室溫水愈低(5°C)或愈高(65°C)均可抑制番茄苗莖伸長，以冷水處理(5°C)能獲得較高莖硬度(g/mm)及壯苗指數(seedhng index;地上部乾物重/株高比值)之番茄苗。冷水處理主要抑制番茄苗之部位為第一節間莖長。冷水灌溉時間於每日清晨(8:00)進行較中午(13:00)及下午(16:00)能夠獲得更矮之植株;每日植株最大生長速率為夜晚至清晨期間。冷水處理四週後，矮化植株的效果最佳，且冷水處理之溫度愈低或處理持續時間愈長，矮化植株效果愈明顯。冷水澆施至栽培介質內，介質土溫能夠在60-90秒內降至最低點，土溫回復至正常溫度約需60分鐘;葉溫鞍上溫變化程度大且葉片回溫時間較介質為短。綜合上述結果顯示5°C冷水灌溉能夠有效的矮化番茄苗及提升種苗品質，可作為種苗產業之參考及應用。In this study,‘Hwalien Yasu No.5'tomato was used to study the effects of different temperatures of irrigation water, parts of plant, timing of irrigation on the shortening and quality of plg-seedling. The purposes of this study were to establish the cold-water irrigation system for plug-seedlings production, and to provide the basic knowledge of shortening seedling for advanced study. The results indicated that shortest seedling was found in the seeding irrigated with the lowest (5∘C) or highest (65∘C) water temperature.However, highest stem strength and seedling index was only found in the seedling irrigated with the 5∘C water. Decrease in the length of first internode was primary responsible for the shortening seedling by cold-water irrigation.Irrigation of cold water at the morning (8:00) or evening (16:00) showed the best results in shortening seedling. After the cold water irrigation, the soil temperature drop to minimum within 60 to 90 sec, and recovered to the room temperature after 60 min. Longer period of cold-water irrigation and lower the cold-water temperature resulted shorter the seedlings. In conclusion, cold-water irrigation system for plug-seedlings production could apply in the commercial usages