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[Objectives] In order to provide a scientific basis for improving yield and quality of pear through nutrient optimization management in China, the current situation of farmers' conventional fertilization management and yield in pear producing area was clarified, and the effects of different nitrogen (N), phosphorus (P2O5) and potassium (K₂O) fertilization measures on the yield and quality were studied. [Methods] The data of 112 journal articles published from 1992 to 2022 on the effect of optimal fertilization on pear yield and quality were integrated and analyzed to study the relationship between pear yield and N, P₂O, and K₂O application rates under conventional and optimal fertilization, and targeted fertilization suggestions were put forward for the main pear producing areas based on the yield effects. [Results] From a national perspective, the average yield of pear was 31 thm and the average amounts of N, P2O5 and K₂O application rates were 453,235 and 320 kg.hm² under conventional fertilization, while the nutrient inputs were relatively high and there were large differences between the main production areas. Compared with conventional fertilization, optimizing N, P2O5 and K₂O fertilization increased fruit soluble sugar content by 5.5%-7.3%, fruit shape index by 1.5%- 1.6%, and vitamin C content by 3.0%-3.4%, and decreased total acid by 3.6%-7.3% and peel firmness by 1.4%-2.2%. Meanwhile, reducing N, P2O5 and K₂O to a certain extent was helpful to increase the yield and quality of pears. Based on this, the appropriate application intervals of N, P2O5 and K₂O could be proposed for each main production area: the optimal input in the western producing area were 292.9-390.5 kg-hm-2, 113.1-169.6 kg.hm² and 71.0-106.4 kg.hm¯², respectively; the optimal inputs in the Yangtze River Basin producing area were 289.0-385.3 kg.hm², 221.7-277.1 kg.hm² and 158.7-238.0 kg.hm², respectively; the best inputs in the Circum-Bohai Sea producing area were 228.1-342.2 kg.hm², 113.9-170.8 kg.hm² and 261.6- 348.8 kg.hm², respectively; the best inputs of the old Yellow River producing area were 258.7-388.1 kg.hm²,164.1-218.8 -2 kg.hm², and 330.1-440.1 kg.hm², respectively. [Conclusions] Optimized fertilization could synergistically improve the yield and fruit quality of pear, and the targeted fertilization recommendations based on this will also help to achieve efficient, green and sustainable development of the main pear producing areas in China. [ABSTRACT FROM AUTHOR]

In order to select the best period for selenium（Se）application for winter jujube（Ziziphus jujuba Mill. var. Dongzao）, a field ex⁃ periment was conducted to study the effects of different Se application（via foliar spraying）periods on total Se content, organic Se ratio, and fruit quality. The NaSeO3 solution（27 mg Se per plant）was applied only once at different growth stages including leaf expansion period （LEP）, fruitlet period（FLP）, fruit swelling period（FSP）, and fruit ripening period（FRP）. The results indicated that total Se content in leaf and fruit increased rapidly when the Se foliar spray was applied at FSP or FRP, and the maximum values were observed when Se was applied at FSP. The Se content in fruit was enhanced from 25 μg·kg-1 to 76 μg·kg-1. Various effects on the fruit quality of winter jujube were found depending on different Se application periods. Foliar Se spray application at FSP showed the best effects for improvement of fruit quality yielding the maximum values of soluble solid, soluble sugar, vitamin C, total flavone content and sugar-acid ratio, which were significantly higher by 13.30%, 17.17%, 16.33%, 29.17%, and 28.89%, respectively, in comparison to that in the control. These results suggested that foliar NaSeO3 spray, at a Se concentration of 45 mg Se·L-1, applied at FSP was a good method for the production of Se-enriched winter jujube fruits. [ABSTRACT FROM AUTHOR]

The objective of this paper is to experimentally study the optimal spectrum and duration of illumination in regulating yield and quality of sweet pepper (Capsium annuum L.) grown in greenhouse. The cultivar of 'Aodaili' was used as the model plant and LED was used as the light source. We compared nine combinations of three light durations (2h, 18:00-20:00; 4h, 18:00- 22:00 and 8h, 18:00-02:00) and three light spectra measured with red (R) : blue (B) ratio at 2:1 (2R1B); 4:1, (4R1B), and 8:1 (8R1B); without supplemental light served as the control (CK). In each treatment, we measured the growth, yield and fruit quality of the sweet pepper. Results showed that the diameter of the canopy, soluble proteins, soluble sugar, and Vitamin C under 2R1B for 2h were the highest, increasing by 24.6%, 33.8%, 15.2% and 29.9%, respectively, compared to those in the CK. Nitrate content and acid-sugar ratio under 2R1B for 8h were the lowest, reduced by 19.4% and 27.0% respectively, compared to that in the CK. The dry biomass of the shoot and whole plant in 4R1B for 2h were the highest, increasing by 58.4% and 62.4% respectively, compared to that in the CK. In contrast, the fresh weight of the shoot and whole plant under 8R1B for 8h were the highest, increasing 55.1% and 48.9%, respectively, compared to that under the CK. Compared to those under the CK, the leaf area, fruit number and single plant yield under 4R1B for 8h increased by 32.4%, 37.9% and 47.2%, respectively. The SPAD, acid-sugar ratio and output-input ratio of the pepper under 8R1B for 2h increased significantly compared with that in CK, while no significant differences were found in the soluble proteins, soluble sugar, Vitamin C and nitrate content between them. These results revealed that the duration and spectrum of the supplemental light had a combined impact on growth, yield and fruit quality of sweet pepper at significant level. Supplemental lighting increased fruit number, single plant yield, soluble proteins, soluble sugar, titratable acid, Vitamin C, nitrate content, acid-sugar ratio. We used electricity consumption to analyze the effect of spectrum and duration of light on plant growth, based on the fuzzy membership function. The best three treatments calculated by the method are in the order of 8R1B for 2h > 4R1B for 8h > 8R1B for 8h. In summary, the optimal supplemental lighting for the greenhouse sweet pepper is 8R1B for 2h. The results presented in this paper has implications for using supplemental lighting to improve green peppers production in greenhouse. [ABSTRACT FROM AUTHOR]

[Objective] The purpose of this paper is to improve the yield and quality of Chinese bayberry and promote the development of green-efficient bayberry industry. [Method] Taking Biqi bayberry as test materials, the application of humic acid soluble fertilizer(HASF)was studied for higher yield and better quality fruit, while two field experiments were conducted in Fumin County and Panlong District, Yunnan Province. [Result] The results showed that the yield and fruit quality were improved by spraying HASF with 800-1000 times concentration at pre-flowering, young fruit and fruit enlarged stage, based on conventional fertilization. The average single fruit weight, yield and net income of bayberry of spraying HASF were significantly higher than those of spraying water(CK), with up to 27. 86 %-31. 54 %, 13. 0 %-13. 4 % and 13. 8 %-14. 2 %, respectively, and the contents of soluble solids and vitamin C(Vc) increased by 18. 4 %-19. 54 %and 18. 56 %-24. 9 %, respectively. However, compared with conventional fertilization, spraying water had no significant effect on fruit yield and quality. [Conclusion] The yield, quality and economic benefit of bayberry could be improved significantly by applying HASF. [ABSTRACT FROM AUTHOR]