不同浮板形式對靜止浮板水培葉用萵苣生長的影響

王加倍　王久興

摘要：研究了不同浮板形式對靜止浮板水培葉用萵苣（Lactuca sativa L.）生長的影響，結(jié)果表明，使用上、下厚度均為2 cm的雙層浮板栽培葉用萵苣效果最好。其株型較大，株高26.72 cm，開展度32.15 cm，莖粗10.90 mm，葉片數(shù)9.81片，葉長23.56 cm，葉寬14.63 cm，葉面積229.78 cm2，根體積9.54 cm3;生物積累量高，冠鮮質(zhì)量為47.51 g，根鮮質(zhì)量9.48 g，總鮮質(zhì)量56.99 g，冠干質(zhì)量3.037 0 g，根干質(zhì)量0.935 3 g，總干質(zhì)量3.972 3 g;營養(yǎng)品質(zhì)與常規(guī)燈芯式深水培相近。因此，進行葉用萵苣靜止浮板水培，可以使用上層厚2 cm，定植孔直徑2 cm，下層厚2 cm，定植孔直徑5 cm的雙層浮板。

關(guān)鍵詞：無土栽培;水培;浮板;葉用萵苣（Lactuca sativa L.）

中圖分類號：S317;S636.2 ? ? ? ? 文獻標(biāo)識碼：A

文章編號：0439-8114（2019）18-0082-04

DOI：10.14088/j.cnki.issn0439-8114.2019.18.020 ? ? ? ? ? 開放科學(xué)（資源服務(wù)）標(biāo)識碼（OSID）：

Effects of different floating plate types on lettuce cultivated by

floating hydroponics technique

WANG Jia-bei1，WANG Jiu-xing2

（1.College of Horticulture，Nanjing Agricultural University，Nanjing 210095，China;

2.College of Horticulture， Hebei Normal University of Science & Technology，Qinhuangdao 066000，Hebei，China）

Abstract： The effects of different floating plate types on lettuce（Lactuca sativa L.） cultivated by floating hydroponics technique were studied. The results showed that the effects of the double-layer floating plate with the upper and lower thickness of 2 cm of lettuce was the best. The plant shape was large. Its plant height was 26.72 cm， plant width was 32.15 cm，stem diameter was 10.90 mm， leaf number was 9.81，leaf length was 23.56 cm，leaf width was 14.63 cm，leaf area was 229.78 cm2， and root volume was 9.54 cm3. The biomass was high. Its fresh mass of crown was 47.51 g，fresh mass of root was 9.48 g， total fresh mass was 56.99 g， dry mass of crown was 3.037 0 g， root dry mass was 0.935 3 g，total dry mass was 3.972 3 g. The nutritional quality was similar to that of conventional lamp core. Therefore， the double-deck floating plate that comprised two pieces polystyrene foam plastics plates， one pieces thickness was 2 cm and the fixed holes diameter was 2 cm，the other pieces thickness was 2 cm and the diameter of planting hole was 5 cm， can be used for hydroponics of leaf lettuce.

Key words： soilless culture; hydroponics; floating plate; lettuce（Lactuca sativa L.）

浮板水培是指將蔬菜定植在漂浮于營養(yǎng)液液面的輕質(zhì)浮板上，蔬菜根系伸入營養(yǎng)液中吸收水分和養(yǎng)分，浮板可在液面移動的一種無土栽培形式。其優(yōu)點是：成本低廉、節(jié)能省工、管理方便。浮板緊貼液面并隨液面升降，栽培過程中無需調(diào)節(jié)液位;栽培池中營養(yǎng)液量比其他水培多，營養(yǎng)液對酸堿緩沖能力強，無需頻繁調(diào)節(jié)。因此，該形式在都市觀光農(nóng)業(yè)領(lǐng)域較受歡迎[1，2]。如果浮板水培的營養(yǎng)液不在水泵驅(qū)動下循環(huán)流動，也不進行曝氣增氧，而處于靜止?fàn)顟B(tài)，筆者稱之為靜止浮板水培。靜止浮板水培設(shè)施簡單，節(jié)省電力，但其使用技術(shù)，鮮見報道。

由于靜止浮板水培的蔬菜根系完全浸泡于營養(yǎng)液中，暴露在空氣中的呼吸根極少，而營養(yǎng)液又處于非流動的靜止?fàn)顟B(tài)，溶解氧含量低，常抑制根系呼吸，導(dǎo)致蔬菜生長緩慢，甚至在高溫環(huán)境下出現(xiàn)漚根現(xiàn)象。因此，如何解決根系呼吸問題，讓根際有足夠的氧氣，是這一栽培方式的技術(shù)關(guān)鍵。