Abstract:

A two-factor split-plot experiment was carried out in the greenhouse of Linyi agricultural meteorological experimental site using muskmelon 'Xizhoumi 25' as the experimental material. The main area was two planting patterns of single row on ridge (D1) and double row on ridge (D2), and the sub-area was three kinds of melon nodes of 11−12 nodes (R1), 13−14 nodes (R2) and 15−16 nodes (R3), a total of 6 treatments, The plant leaf area and photosynthetic parameters, yield components and fruit quality were measured to explore the effects of different planting patterns and melon retention nodes on photosynthetic characteristics, yield and quality of muskmelon in greenhouse. The results showed that the photosynthetic efficiency of single row planting mode was higher than that of double row planting mode. The fruit diameter, single fruit weight and soluble sugar content of single row planting mode were significantly increased by 2.4%, 11.1% and 9.5%, respectively, compared with double row planting mode (P<0.05). The effect of node location on vegetative growth and reproductive growth of the plant was obvious. The photosynthetic characteristics, fruit length, fruit diameter and single fruit weight of R2 treatment were the best, and the single fruit weight was 9.41% and 14.73% higher than that of R1 and R3, respectively (P<0.05). The effect on fruit quality was extremely significant (P<0.01). The R1 treatment had the highest soluble sugar content, the R2 treatment had the highest sugar-acid ratio, and the R3 treatment had the highest VC and titratable acid content. The interaction between planting pattern and node position had significant effects on leaf area, SPAD, Pn, Ci, Gs and Tr of muskmelon (P<0.05), and the SPAD, Pn, Gs and Tr values of D1R2 combination leaves were the largest before maturity stage. Interaction effection had a significant effect on fruit length (P<0.05), and had a very significant effect on fruit diameter, fruit shape index and single fruit weight (P<0.01). Among them, the fruit diameter value of D1R1 combination was the largest, and the fruit shape index of D1R3 was the highest. The fruit length and single fruit weight of the D1R2 combination were the largest, and the average single fruit weight was 28.7% higher than that of other combinations. The interaction had a significant effect on VC content (P<0.05), and had a very significant effect on titratable acid, soluble sugar content and sugar-acid ratio (P<0.01). Of these, the D2R3 combination had the highest VC content, D1R3 had the highest titratable acid content, D1R1 had the highest soluble sugar content and D1R2 had the highest sugar-acid ratio. Under the same planting density and number of functional leaves (22500 plants·ha⁻¹, 25 nodes topping), the three evaluation indexes of yield flavor and taste and VC content of single row planting on ridge and 13−14 nodes interaction (D1R2) mode were the highest, and the comprehensive evaluation of its commodity value was the best. It is recommended that this mode of planting should be applied and generalized in the vertical cultivation of the early spring melons in greenhouses in the north of China.

Key words: Muskmelon, Planting patterns, Fruiting nodes, Photosynthetic characteristics, Yield and quality