間作裨益有機栽培之青蔥生產

Beneficial Intercropping in the Organic Production of Green Onions (Allium fistulosum L.)

本試驗之目的在試探有機栽培青蔥間作萬壽菊或番茄之效果。試驗含五種處理：青蔥2行間作萬壽菊1行（2:1）、青蔥4行間作萬壽菊1行（4:1）、青蔥4行間作番茄1行（4:1）、青蔥6行間作番茄1行（6:1）、以及青蔥單作。結果大部分的間作處理皆增加青蔥單叢重量及平均單位面積產量。各處理中以青蔥2行間作萬壽菊1行獲得最高單叢重量及平均單位面積產量。間作處理的土地等效比例皆大於1，且作物產值高於單作。2008年春季之試驗各處理中以青蔥單作組銹病感染率最早達到100%，且最嚴重；青蔥和萬壽菊間作降低早期感染率及嚴重程度。 Four intercropping patterns and one monocropping as control were tested in an organic production of green onions (Allium fistulosum L.). The four patterns were as follows: (1) one row of marigold (Tagetes erecta L.) for every 2 rows of green onion, (2) one row of marigold for every 4 rows of green onion, (3) one row of tomato (Lycopersicon esculentum Mill.) for every 4 rows of green onion, and (4) one row of tomato for every 6 rows of green onion. The test was repeated for two crop seasons. Intercropping 1 row of marigold with every 2 rows of green onions produced the highest per cluster weight as well as the highest per 100 m^2 mean yield of green onions. Other patterns of intercropping also had a strong tendency to increase per cluster weight and mean yield over monocropping. The land equivalent ratio was higher than 1 in all four intercropping patterns; thus the economic return of intercropping was higher than that of monocropping green onions. In the 2008 observation, intercropping delayed the infection and reduced the severity of green onion rust disease. Intercropping green onions with marigold was particularly effective to mitigate this disease.