本研究以微噴灌之定量供水設備並設立水分張力計,將土壤含水量設計區分為20%(-4~-7分巴)、15%(-12~-17分巴)及10%(-20~-40分巴)等三處理,以調查對5年生芒果植株之抽梢、抽花穗、開花、結果及果實品質之影響。當土壤水分充足時即土壤含水量為15~20%,自枝條修剪後(8月上旬)至抽穗時有61%枝條抽2次梢,39%抽3次梢,末次梢的大小;葉數平均17片,葉面積計1199 cm^2,莖粗12 mm,莖長平均21 cm。抽花穗速度較慢,最終抽花穗率為85.4~94.4%,平均花穗長度48 cm。每花穗小花數平均3415朵,其中雄花佔47%,兩性花佔53%。開花期間3月13日至4月14日,開花高峰期為3月25日。開花後每花穗之著果情形;全無著果的花穗比率平均32%,每花穗平均著果量2.6個,每株著果量22~26個。每株的最終產量為平均20~21個,總重達3.7~5.0公斤,單果重為185~238公克。果實成熟後果肉呈黃色至淡黃色,果肉比率佔75~76%,糖度12.8 ˚Brix,酸度0.17~0.18%,其榨汁率達85~90%。當土壤含水量減少至10%時,僅抽2次梢的枝條增加25%,亦即減少25%枝條抽3次梢,末次梢的大小;葉片少2片,葉面積減少371 cm^2,莖粗小3 mm,莖長度短2 cm。抽花穗率高且較快速,最終抽穗率提高2.5~11.5%,花穗長度短小13 cm。每花穗小花數少306朵,花穗中雄花比率增加13 %。關花期提早10天,開花高峰期則提早8天(3月17日)。開花後每花穗著果情形;全無著果的花穗比率增加24%,每花穗著果量減少73%,每株著果量減少57~86%。每株的最終產量;個數減少1倍,重量減少3~4倍。果肉成熟呈金黃色,果汁率少4~9%,果肉比率亦少6~7%,但糖度增加4.2 ˚Brix。
In an experiment from August 1994 to July 1995 carried out at the Hsin-Hwa branch station of Tainan District Agricultural Improvement Station, 5-year-old mango cv. Iwin trees planted in holes at a size of 1.7 m length × 1.7 m width × 1.5 m depth were subjected to 3 levels of soil water content (SWC) using a microsprinkler system. Thereafter, 3 treatments consisted of: trees irrigated each day with total supply with 7 litre to maintain SWC with 20%, trees irrigated each day with total supply with 3.5 litre to maintain SWC with 15%, and trees irrigated each day with total supply with 1.4 litre to maintain the SWC with 10%.There were significant differences in shoot and inflorescence growth, flower numbers and fruit-set percentage in each plant among treatments. The trees in 10% SWC had the smallest fruit and lowest yield, pulp concentration and juice content, while highest in sugar content among the treatments. The total yield of the trees in 15% SWC was lower than that of 20% SWC treatment. The 20% SWC treatment produce the largest fruit and higest yield and juice content.