Screening of Red-flesh Small Watermelon Varieties for Substrate Cultivation in Spring Greenhouses

[Objectives] This study was conducted to screen small watermelon varieties suitable for spring greenhouses. [Methods] The field traits, yield traits, quality traits and commodity of 6 new red-flesh watermelon varieties were compared. [Results] "Jingmei 3 K" and "Sumeng No.5" had obvious advantages in quality traits, yield traits, and commodity traits. The yield reached 62 163.3 and 63 733.5 kg/hm2, respectively;the single melon weights reached 2.16 and 2.21 kg, respectively;and the central sugar content reached 13.2% and 13.1%, respectively. Meanwhile, the juice contents were high, and the taste was sweet and refreshing. They are suitable for planting under the condition of substrate cultivation technology. [Conclusions] This study provides a theoretical basis for large-area substrate cultivation and production.

Effects of Different Amino Acid Fertilizers on Growth,Development and Quality of Mini Watermelon under Substrate Cultivation

In order to select suitable mini watermelon varieties for spring greenhouse cultivation under substrate cultivation,the field character,yield character,quality character and trade trait of six new mini watermelon varieties with red flesh were compared in the test.The results showed that mini watermelon applied with alanine and arginine had obvious advantages in quality character,yield character and trade trait.The yields reached 3876.8 and 44120.20 kg/667m2;the weight of single melon reached 1.98 and 2.10 kg;and the central sugar content reached 13.34%and 13.25%,respectively.Meantime,mini watermelon was juicy,sweet,tasty and refreshing,and was suitable for planting under substrate cultivation.

Improved root zone temperature buffer capacity enhancing sweet pepper yield via soil-ridged substrate-embedded cultivation in solar greenhouse

A novel soilless cultivation method,called as soil-ridged substrate-embedded cultivation(SSC)was invented,and an experiment was designed to investigate root zone temperature and production efficiency of sweet pepper cultivated by two SSC patterns,i.e.,SSC-P(polyethylene groove inserted)and SSC-W(wire-mesh groove inserted),and also other two cultivation methods,i.e.,soil ridge(SR)and naked polyethylene groove(PG).Results showed that PG,SSC-P and SSC-W increased the average minimal root zone temperature by 1.01℃,0.75℃,and 1.16℃ compared to SR(16.33℃)during March 16-20,2015.During June 1-5,SSC-P and SSC-W decreased the average maximal root zone temperature by 1.28℃ and 1.29℃ compared to SR(34.99℃),while PG increased it by 1.44℃.PG,SSC-P,and SSC-W decreased the differences of average daytime and night time temperatures by 1.34℃,2.13℃,and 2.88℃ compared to SR(4.56℃)during early stage.However,SSC-P and SSC-W decreased temperature differences of average daytime and night time by 0.9℃ and 1.07℃ compared to SR(0.95℃)during later stage,but PG improved by 2.85℃.Temperature difference of daytime and night time of SSC-W was minimal,and the temperature difference between the diurnal highest and the lowest temperature of SSC-W was also minimal.The buffer capacity of SSC-W was slightly better than that of SSC-P.SSC-W significantly improved the growth of sweet pepper compared to SR.Similarly,fruit yield per square meter of sweet pepper cultivated on SSC-P and SSC-W improved by 21.24%and 50.33%,respectively compared to SR(3.06 kg/m^(2)),while PG lowered the yield by 13.72%.SSC-W was a better SSC pattern compared with SSC-P in terms of production efficiency.

Adjusting the nutrient solution formula based on growth stages to promote the yield and quality of strawberry in greenhouse

To optimize the nutrient supply of strawberry,fertilization was reduced as much as possible on the premise of satisfying the elements needed for strawberry growth.This study put forward a modified nutrient solution formula(NM)by adjusting the ratios of N/K,K/Ca,NO_(3)^(-)-N/NH_(4)^(+)-N in vegetative growth,flowering and fruiting,and fruit expanding stages based on Yamasaki strawberry nutrient solution formula(NY).Taking the NY as the control group,the NM was verified with elevated-grown‘Ssanta’strawberry using three different substrates(Vulcanics-added substrate,Horticultural substrate,Comme rcial substrate)in greenhouse.The results indicated that under the NM treatment,strawberry plants had better photosynthesis in the vegetative growth stage and flowering and fruiting stage,and the first crop yield and total crops yield per plant also increased by 20%.Although the vegetative growth stage was longer,it entered the full fruiting stage earlier so that the maturity stage was advanced one week.Compared to strawberries grown in horticultural substrate irrigated with NY,the fruit yield per plant of‘Ssanta’strawberry grown in horticultural substrate irrigated with NM increased by 26%,and the sugar-acid ratio and vitamin C content of primary fruits reached 10.6 and 74.1 mg/100g,improving by 41%and 34%respectively.The NM based on the growth stage can optimize the element needs of strawberry in all growth and development stages and maintain the substrate’s pH stability,improving the yield and quality of‘Ssanta’strawberry under substrate cultivation.Therefore,it is recommended to use the horticultural substrate irrigated with the modified nutrient solution for the‘Ssanta’strawberries cultivation elevated in greenhouse to improve the economic benefit of strawberry cultivation.