Temperature, as an important feature of hydroponic nutrient solution, is closely related to dissolved oxygen content of nutrient solution and growth status of plant roots. How to precisely adjust the temperature of nu...Temperature, as an important feature of hydroponic nutrient solution, is closely related to dissolved oxygen content of nutrient solution and growth status of plant roots. How to precisely adjust the temperature of nutrient solution is the key to obtain high quality and high yield of hydroponic vegetables over summer. With Lactuca sativa vat. crispa ＇Luosheng No.3＇ as the test material, the effect of chiller cooling technology on the temperature of nutrient solution, as well as on the yield and quality of Luosheng No.3, in over-summer hydroponic cultivation was studied. The results showed that the chiller cooling technology controlled the nutrient solution temperature in a reasonable range （（20 ± 1）℃） and promoted the growth and dry matter accumulation of Luosheng No.3, instead of affecting the quality. In short, the chiller cooling technology is applicable to the temperature regulation of nutrient solu- tion in hydroponics over summer.展开更多
The coupling effect of nutrient solution EC （electrical conductivity） levels and CR （circulation rate） on the morphology and quality, in hydroponically grown lettuce was assessed. Lettuce was grown at 5 treatments...The coupling effect of nutrient solution EC （electrical conductivity） levels and CR （circulation rate） on the morphology and quality, in hydroponically grown lettuce was assessed. Lettuce was grown at 5 treatments fi＇om High EC ＆ Low CR to Low EC ＆ High CR. The environmental parameters were controlled in a 20 m^2 plant factory during the hydroponic cultivation with the following values： irradiated by blue and red light-emitting diode lighting with PPFD （photosynthetic photon flux density） value of 150 mol·m^-2·s^-1 for 16 hours per day; Temperature was maintained at 22.0 ℃ during the photoperiod and 16.0 ℃ in dark cycle. The results demonstrate that growing lettuce can be adopted using nutrient solution with lower EC levels and higher CR. The results also indicate that the effect of bi-directional coupled EC and CR resulted in expansion of root length but reducing the root biomass. Nitrate content was significantly reduced.展开更多
Tomato seedlings were grown in substrate culture with pots. The formulation of Holland Greenhouse Horticulture Research Institute was used(as CK) and the effects of different Ca concentrations(LCa, CK and HCa)on growt...Tomato seedlings were grown in substrate culture with pots. The formulation of Holland Greenhouse Horticulture Research Institute was used(as CK) and the effects of different Ca concentrations(LCa, CK and HCa)on growth, yield, and fruit quality(protein, Vitamin C, nitrates, organic acid and soluble sugar) of tomato were studied keeping concentrations of other nutrients unchanged in the nutrient solution. The results showed that parameters related to the growth of tomato(plant height and Stem diameter), changes of tomato yield per plant and quality of tomato fruits were the highest when the plants were grown at 20% Ca treatments. In the second study, increased EC concentrations of nutrient solution resulted in stronger plants with improved yields and quality. Four different concentration gradients of nutrient solution treatment were designed based on the results of the first research stage(EC=1.5, 2.5, 3.5, 4.5 m S/cm, respectively). The single tomato plant had the highest production which is 2 268.994 g/plant, when the nutrient solution strength was at EC=1.5 m S cm, whereas they have the best fruit quality when the solution strength at EC 4.5 m S/cm. This suggests the need for wide popularization of the nutrient solution formula in large areas to improve the tomato production.展开更多
基金Supported by Science and Technology Innovative Leading Fund of Ningxia Academy of Agriculture and Forestry Sciences(NKYZ-16-1101)~~
文摘Temperature, as an important feature of hydroponic nutrient solution, is closely related to dissolved oxygen content of nutrient solution and growth status of plant roots. How to precisely adjust the temperature of nutrient solution is the key to obtain high quality and high yield of hydroponic vegetables over summer. With Lactuca sativa vat. crispa ＇Luosheng No.3＇ as the test material, the effect of chiller cooling technology on the temperature of nutrient solution, as well as on the yield and quality of Luosheng No.3, in over-summer hydroponic cultivation was studied. The results showed that the chiller cooling technology controlled the nutrient solution temperature in a reasonable range （（20 ± 1）℃） and promoted the growth and dry matter accumulation of Luosheng No.3, instead of affecting the quality. In short, the chiller cooling technology is applicable to the temperature regulation of nutrient solu- tion in hydroponics over summer.
文摘The coupling effect of nutrient solution EC （electrical conductivity） levels and CR （circulation rate） on the morphology and quality, in hydroponically grown lettuce was assessed. Lettuce was grown at 5 treatments fi＇om High EC ＆ Low CR to Low EC ＆ High CR. The environmental parameters were controlled in a 20 m^2 plant factory during the hydroponic cultivation with the following values： irradiated by blue and red light-emitting diode lighting with PPFD （photosynthetic photon flux density） value of 150 mol·m^-2·s^-1 for 16 hours per day; Temperature was maintained at 22.0 ℃ during the photoperiod and 16.0 ℃ in dark cycle. The results demonstrate that growing lettuce can be adopted using nutrient solution with lower EC levels and higher CR. The results also indicate that the effect of bi-directional coupled EC and CR resulted in expansion of root length but reducing the root biomass. Nitrate content was significantly reduced.
文摘Tomato seedlings were grown in substrate culture with pots. The formulation of Holland Greenhouse Horticulture Research Institute was used(as CK) and the effects of different Ca concentrations(LCa, CK and HCa)on growth, yield, and fruit quality(protein, Vitamin C, nitrates, organic acid and soluble sugar) of tomato were studied keeping concentrations of other nutrients unchanged in the nutrient solution. The results showed that parameters related to the growth of tomato(plant height and Stem diameter), changes of tomato yield per plant and quality of tomato fruits were the highest when the plants were grown at 20% Ca treatments. In the second study, increased EC concentrations of nutrient solution resulted in stronger plants with improved yields and quality. Four different concentration gradients of nutrient solution treatment were designed based on the results of the first research stage(EC=1.5, 2.5, 3.5, 4.5 m S/cm, respectively). The single tomato plant had the highest production which is 2 268.994 g/plant, when the nutrient solution strength was at EC=1.5 m S cm, whereas they have the best fruit quality when the solution strength at EC 4.5 m S/cm. This suggests the need for wide popularization of the nutrient solution formula in large areas to improve the tomato production.
