Influence of light quality on flowering characteristics, potential for year-round fruit production and fruit quality of blueberry in a plant factory

A Review for Southern Highbush Blueberry Alternative Production Systems

“…In contrast to high tunnel production, environmental conditions such as temperature, humidity, light, and CO 2 concentrations can be controlled in greenhouses and plant factories (closed growing systems similar to growth chambers), making it possible to produce fruit year-round, especially in plant factories [29].…”

“…In the current literature, most SHB research in greenhouse or plant factory conditions is focused on investigating plant growth, photosynthetic ability, and fruit quality by adjusting the photoperiod, temperature, humidity, and other environmental factors [29][30][31][32]. Studies exploring the potential yield in greenhouse production is limited to a study conducted by Motomura et al [33] in Volcano, Hawaii.…”

“…Hence, there is a lack of research on optimizing management practices to maximize SHB yield in greenhouse or plant factory production. Controlling temperature is more feasible in plant factories than in greenhouses [29,30,34,35]. Spann et al [35] compared plant growth under 28 and 21 • C and discovered that flower bud initiation and whole-plant carbohydrate concentration was significantly reduced at 28 • C. Aung et al [30] found that the optimal temperature for SHB cultivars 'Misty' and 'Sharpeblue' should be around 15 • C during dark periods and 25 • C in light periods, which agrees with Kameari et al [34] and Cho et al [29].…”

“…Controlling temperature is more feasible in plant factories than in greenhouses [29,30,34,35]. Spann et al [35] compared plant growth under 28 and 21 • C and discovered that flower bud initiation and whole-plant carbohydrate concentration was significantly reduced at 28 • C. Aung et al [30] found that the optimal temperature for SHB cultivars 'Misty' and 'Sharpeblue' should be around 15 • C during dark periods and 25 • C in light periods, which agrees with Kameari et al [34] and Cho et al [29]. The experiments on SHB cultivars 'Misty' and 'Sharpeblue' showed that relative humidity above 40% can avoid stomatal closure under low humidity and below 80% can reduce disease pressure under high humidity [29,30].…”

“…Although photosynthetic rates increase with light intensity from 0 to 1000 µmol.m −2 .s −1 , temperature also increases with light intensity, and thus, more energy is consumed [30]. High-pressure sodium lamps or light-emitting diode (LED) lights at an intensity of 300 to 500 µmol.m −2 .s −1 , or at even lower light intensities of 150 to 350 µmol.m −2 .s −1 , have been reported to provide enough radiation for sufficient photosynthesis and plant growth [29][30][31]. Light quality is able to induce different responses in blueberry flowering characteristics, with blue light (approximately 450 nm) advancing flowering and red light (approximately 630-660 nm) delaying flowering.…”