- 學位論文
植物工場內草莓水耕栽培
Cultivation of strawberry in plant factory using hydroponic system
摘要
於植物工場栽培草莓 (Fragaria ×ananassa Duch.) 可在臺灣週年生產健康種苗及無毒果實，然而循環式水耕栽培系統及果實的生產流程仍迄待建立。因此本研究目的在評估磁驅式及加壓式馬達循環系統對植株營養生長的影響、減氮及紅光/遠紅光比例對草莓開花誘導的影響；此外，‘桃園一號’與‘長柄’草莓之生育差異也一併比較。 以磁驅式及加壓式馬達循環系統栽培具2-3片葉之‘桃園一號’走莖苗，並以非循環系統為對照，比較養液系統對植株營養生長之影響及養液離子消耗狀況。所有參試植株皆生長勢良好，葉色濃綠、無任何元素缺乏症狀，新葉SPAD值、葉面積、累計走莖數與葉片數系統間無顯著差異，但循環系統之植株生物量顯著高於非循環系統，但三種養液系統下的。葉片元素分析結果顯示，葉片中巨量元素含量較不受養液系統影響；所有系統下之微量元素含量皆低於傳統栽培的建議值，尤其循環系統中磁驅式馬達系統下Mn、Cu及Zn含量。此外，分析現有養液補充模式下，磁驅式馬達離子變化趨勢規律穩定，K+、Mg2+及Ca2+之累計消耗比率為60%，養液濃度表現持平。NO3-及SO42-之累計消耗比率為83%及38%則分別導致養液離子濃度下降及上升。離子含量變化趨勢顯示現行養液配置及補充模式需再修正，方可提高循環式栽培效益。參考磁驅式馬達系統植株生長情形、穩定的養液變動趨勢、及其葉片Mn、Cu及Zn等元素含量，推測其植株生長環境穩定，逆境少的狀況下不需大量誘發抗氧化酶，因而對Mn、Cu及Zn等元素需求量較低。加壓式馬達因水壓不穩，易於出水口發生養液噴濺，因此離子濃度變化較不規律。 本研究亦評估花芽誘導前養液減氮處理及不同紅光比例處理‘長柄’草莓對花芽分化的促進效果。減氮試驗結果不顯著，可能與處理時間太短及誘導期間光週期控制失常有關。在低溫短日誘導下利用高紅光比例 (HR, 紅光/遠紅光比：14.2) 與低紅光比例 (LR, 紅光/遠紅光比：7.2) 之人工光源栽培‘長柄’草莓，結果顯示HR處理可顯著提高具分化花芽之植株數。LR處理之葉面積較HR高；但紅光比例不影響花序數及冠莖數。 ‘桃園一號’及‘長柄’草莓生殖生長期間的累計葉片數、走莖數及花序數皆無顯著差異。試驗植株皆疏去三級以上果實後，進行疏果對果實品質影響之試驗，疏去一級果會降低‘長柄’的單株產量及平均果重，但不影響‘桃園一號’。在植物工場中生產‘長柄’草莓建議需保留一級及二級果，並及早疏去三級以上花朵。‘桃園一號’建議僅保留二級果，因為一級果較易形成畸形果且疏去一級果不影響平均果重。
並列摘要
The year round production of pesticide-free runner plants and fruits in Taiwan could be achieved by cultivating strawberry (Fragaria xananassa Duch.) in the plant factories; however, the hydroponic circulation system and fruit production protocols were remained to be built. Therefore, the objective of this study was to evaluate the effect of circulation system with magnetic drive pump and booster pump on plant vegetative growth, and the effect of reducing nitrogen and red/far red light ratio on flower induction. The the reproductive performance between ‘Taoyuan No.1’ and ‘Changbin’ was alos investigated. ‘Taoyuan No.1’ plants with 2-3 leaves were grown under non-circulation system (NCS) and circulation system (CS) with booster pump or magnetic drive pump to evaluate the impact of solution system on vegetative growth and ion consumption in solution. All the plants grew vigorously with dark green leaves without showing any nutrirtion deficient symptom. The SPAD of new leaf, leaf area, accumulative number of runners and leaves was not significant different among systems; however, the plant biomass was significantly higher in CS than in NCS. The result of leaf element analysis showed that the macronutrient elements were more independent to solution system, and the micronutrient elements were much lower than recommended value of filed grown strawberry plants particularly the leaf Mn、Cu and Zn content in CS driving by magnetic pump. Moreover, the variation of nutrient concent in hyderponic solution driven by the magnetic pump was more stable under the current supplement protocol. In such system, the accumulated consumption of K+, Mg2+ and Ca2+ within the 7 weeks of experinment period was about 60% led to the ion concent maintained at the same level. The accumulated consumption of NO3- and SO42- was 83% and 38% resulted in steady decrease and increase in ion content, respectively. Therefore, the preparation and suppliment of the hydroponic solution should be reprogrammed. The vigorous growth and low leaf Mn、Cu and Zn along with ion content variation in the plants grown in magnetic pump drived CS revealed that the antioxidant enzyme system was less induced, which might suggest that the plants were less stressed. The fluctuation ion concent was resulted from the solution splash caused by the unstable water pressure in booster pump CS. The effect of nitrogen reduction perior to flower induction and red/far red light ratio on inflorescences initiation of ‘Changbin’ strawberry has been evaluated. The nitrogen reduction experiment did not significantly affected inflorescences initiation, which might due to the treamtment period was not sufficient and system error in photoperiod controlling. High red light ratio (HR, red/far red: 14.2) increased the number of flowering plants and low red light rotio (LR, red/far red: 7.2) enlarged leaf area. However, the number of inflorescences and crowns were not significant different between HR and LR. The the accumulative number of leaves, runners and inflorescences of ‘Taoyuan No.1’ and ‘Changbin’ were not significant different during the whole reproductive period. Each plant was controlled to have 5 primary and secondary fruits, removing fruits of tertiary and above order, to evaluate the effect of primary fruit on fruit qualiry and yield. Removing primary fruit decreased yield per plant and average fruit weight in ‘Changbin’ but not ‘Taoyuan No.1’. The result suggest that in the cultivation of ‘Changbin’ in plant factory, both primary and secondary fruit should be kept and removing flower of tertiary and above order as early as possible. For ‘Taoyuan No.1’, only secondary fuirts shold be saved because malformation fruit is often fromed in primary fruits and thinning primary did not significantly affect average fruit weight.