Effect of Pot Volume on the Growth of Sweetpotato Cultivated in the New Hydroponic System

Abstract

Hydroponics is an effective means for promoting plant growth as it facilitates water and nutrient uptake by plant roots. For increasing the production of sweetpotato (Ipomoea batatas), we developed the new hydroponic cultivation system in which tuberous roots were grown in solid media in the pots whereas fibrous roots were grown in the nutrient solution. Using this method, the effect of pot volume (1.6, 3.0, and 4.5 L) on the growth of sweetpotato was investigated. When plants were grown in small-sized pots (1.6 L), the fresh weight of the top and that of tuberous roots were decreased compared with plants grown in 3.0 L and 4.5 L pots. No clear difference was observed between the top and the tuberous roots in terms of the dry weight ratio, regardless of the pot size. The number of tuberous roots per plant and the maximum tuberous root weight were not influenced by the pot size either. However, the number of tuberous roots weighing more than 100 g was decreased in plants grown in small pots. Some of the tuberous roots grown in this hydroponic system contained a non-hypertrophic parts with severely lignified metaxylems. These results suggest that the environment surrounding the tuberous root influenced by the pot volume may be important for root enlargement in this hydroponic system.

Variation in ‘Bayou Belle’ and ‘Beauregard’ Sweetpotato Root Length in Response to Experimental Phosphorus Deficiency and Compacted Layer Treatments

“…In past studies with this experimental system, root length increase slowed down after 20 d with the onset of storage root swelling with the accompanying depletion of nutrients in the root zone (Villordon et al, 2012(Villordon et al, , 2013. Sakamoto and Suzuki (2018) documented the direct influence of pot size on root size but not number in sweetpotato grown in a modified hydroponic system. Because of the possible limitations of the growing conditions, further studies are needed to further the understanding of the possible interactive roles of genotype and spatial P availability on sweetpotato SRL in field conditions.…”

Effect of Partial Excision of Early Taproots on Growth and Components of Hydroponic Carrots

“…In radishes, gene expression that is involved in lignin synthesis was reportedly reduced during taproot thickening [36]. Lignification of storage roots has also been reported in the restriction of root thickening in sweet potatoes [5,37]. These findings suggest that root treatment of hormones controlling the lignification could be a valuable strategy to increase sink biomass in root vegetables.…”

“…Plants were cultivated at 20 • C under 250 µmol m −2 s −1 PPF for 16 h under FLs. Growth parameters of leaf number, shoot length, and taproot diameter were measured at 0, 1, 2, 3, 5,6,7,8,10,12,14,16,19,21,23, and 28 days after taproot excision. At 28 days after taproot excision, the plants were harvested, and growth parameters and components were then analyzed.…”

“…In this system, storage roots developed between the surface of the hydroponic solution and nutrient-absorbed rockwool slabs, but not in the hydroponic solution. When sweet potatoes were cultivated in a two-layer system consisting of an upper vermiculite-containing pot and a lower nutrient solution, the roots thickened in the pots, but not in the nutrient solution [5]. In potatoes, aeroponics can continuously produce small tuberous roots only in the upper root zone where they are in direct contact with air [6].…”

Effect of Nutrient Solution Concentration on the Growth of Hydroponic Sweetpotato

“…Sweetpotato plants fail to develop storage roots under continuous waterlogging conditions [41][42][43]. Therefore, several studies have established hydroponic methods of sweetpotato cultivation to avoid soaking the hypertrophic sites of roots in water [41][42][43][44][45][46][47][48][49].…”