Effects of drip fertigation on yield, quality of red globe grape and distribution of soil NPK

Objectives Drip fertigation has been proved to be effective in increasing yields and quality of Red Globe and decreasing the leaching loss of fertilizer nutrients. The proper fertilizer dosage in drip irrigation in grape production was studied.

Methods A field trail was conducted in Huailai County, Hebei Province, 15-year-old grape cultivar of ‘Red Globe’ was used as test materials. The experiment was subjected to 5 fertilizer supply ways and levels, including traditional irrigation and fertilization (CK), traditional fertilization + drip irrigation (FCK + D), fertigation Ⅰ (F1 + D), fertigation Ⅱ (F2 + D) and fertigation Ⅲ (F3 + D). The water consumption in drip irrigation is 55% of traditional irrigation, and the total amount of fertilization in CK and FCK + D were the same (N, P₂O₅ and K₂O: 2708.7, 2615.45 and 1315.2 kg/hm²). Compared with CK, F1 + D’s N, P₂O₅ and K₂O were decreased by 68.32%, 87.61% and 40.47%, respectively, and 17.31% of P and 12.54% of K were reduced in F2 + D and 18.53% of N was further reduced in F3 + D. The N, P and K contents in 0−100 cm depth of soil profile were measured during the grape growing season, the yield, thousand-grain mass, soluble solid content, pH, titratable acidity, Vc content of fresh fruits were analyzed. The water utilization efficiency and partial fertilizer productivity were calculated after the final harvest.

Results In 2012 and 2013 the grape yields of the CK were 24115 kg/hm² and 23020 kg/hm², and those of the F1 + D were 28830 kg/hm² and 27272 kg/hm², which were higher than those of the CK, and increased by 19.0% in average. The thousand-grain mass of the F3 + D were 11.39 and 11.47 kg, and increased by 7.2% in average. The Vc contents of the F1 + D, F2 + D and F3 + D were higher than that of the CK, and increased by 16.7%, 15.2% and 15.6%. On the other hand, the fertilizer and irrigation amount during the whole growth stage had a significant effect on the distribution of soil NPK, there was no significant difference between fertigation and CK in the soil layer of 0−60 cm, but the accumulation of nitrogen and phosphorus in 60−100 cm soil layer of the F1 + D were the lowest, and were 21.37 and 28.56 mg/kg respectively, the accumulation amounts of potassium of the F1 + D, F2 + D and F3 + D were lower than CK, however, there was no difference among F1 + D, F2 + D and F3 + D, which were 126.11, 117.75 and 139.00 mg/kg. In addition, their maximum water utilization ratio and PFP were higher than CK, which were increased by 209.1% and 266.3% respectively. Compared with the traditional management, the water and fertilizer input and labor cost were saved by 17857.5, 18547.5, 17752.5 yuan/hm², respectively.

Conclusions Using drip fertigation technology could greatly improve yields and quality of grapes, reduce N and P leaching, and increase farmers’ income. And the best comprehensive performance of these treatments in production, quality and efficiency was the F1 + D, which increased by 47145−51024 yuan/hm² compared with the CK.