New artichoke varieties has been released using seed-systems. Such seed-systems require research efforts to generate guidelines principles for producing high-quality transplants. The main aim of this research was to establish the optimum nitrogen source and rate effect on the quality of artichoke cv. Concerto transplants during a nursery period of 44 days. Transplants were produced using peat as substrate in polystyrene trays with 60 holes, which have been left floating during 30 minutes in a container purposed to performing the subirrigation process. On May 18, at the first true-leaf stage, started the subirrigation - three times per week - of the seedlings by using two N-sources (ammonium nitrate and urea) and 4 rates (50, 125, 200, 275 mg L-1) in the nutrient solution. All the assessments herein reported were done at the 4th true-leaf stage (June 30). Transplant height, leaf area, and fresh weight was higher with urea than ammonium nitrate. With N dose increasing, height, number of leaves, leaf area, fresh weight, specific leaf area (SLA) and SPAD index increased. Leaf number was higher at 200 mg L-1, while dry matter content was at 50 mg L-1. The highest N-rate had a positive effect on height, leaf area, fresh weight, and SLA of the transplants, altogether being well-fitted by a cubic relationship between these variables and N-dose. Alternatively, SPAD index suited well a linear relationship to N-dose. No interaction between N-dose and source was found. To produce high quality artichoke transplants can be appropriate to choose urea as N-source with a rate between 200-275 mg L-1.
N-rate and N-source for producing artichoke cv. Concerto transplants in float bed under greenhouse conditions
SANTAMARIA, Pietro;
2007-01-01
Abstract
New artichoke varieties has been released using seed-systems. Such seed-systems require research efforts to generate guidelines principles for producing high-quality transplants. The main aim of this research was to establish the optimum nitrogen source and rate effect on the quality of artichoke cv. Concerto transplants during a nursery period of 44 days. Transplants were produced using peat as substrate in polystyrene trays with 60 holes, which have been left floating during 30 minutes in a container purposed to performing the subirrigation process. On May 18, at the first true-leaf stage, started the subirrigation - three times per week - of the seedlings by using two N-sources (ammonium nitrate and urea) and 4 rates (50, 125, 200, 275 mg L-1) in the nutrient solution. All the assessments herein reported were done at the 4th true-leaf stage (June 30). Transplant height, leaf area, and fresh weight was higher with urea than ammonium nitrate. With N dose increasing, height, number of leaves, leaf area, fresh weight, specific leaf area (SLA) and SPAD index increased. Leaf number was higher at 200 mg L-1, while dry matter content was at 50 mg L-1. The highest N-rate had a positive effect on height, leaf area, fresh weight, and SLA of the transplants, altogether being well-fitted by a cubic relationship between these variables and N-dose. Alternatively, SPAD index suited well a linear relationship to N-dose. No interaction between N-dose and source was found. To produce high quality artichoke transplants can be appropriate to choose urea as N-source with a rate between 200-275 mg L-1.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
