Author : Khabo Lemohang Harold Semuli
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (956 download)
Book Synopsis Nitrogen Requirements for Cabbage (brassica Olerecea Capitata) Transplants and Crop Response to Spacing and Nitrogen Top-dressing by : Khabo Lemohang Harold Semuli
Download or read book Nitrogen Requirements for Cabbage (brassica Olerecea Capitata) Transplants and Crop Response to Spacing and Nitrogen Top-dressing written by Khabo Lemohang Harold Semuli and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: To determine the optimum nitrogen application level required for the production of good quality Drumhead cabbage (Brassica oleracea var. capitata) transplants, a glasshouse experiment was conducted. Depending on water requirements, transplants were fertigated every two days (for the first four weeks) and every day (for the last two weeks) by floating trays in plastic tubs containing nutrient solution at 0, 30, 60, 90 and 120 mg ĢL-1 N until field capacity was reached. Increasing nitrogen from 0 to 120 mg ĢL-1 increased shoot and root mass of cabbage transplants with more dry mass being partitioned to the shoot than to the roots. Nitrogen at 120 mg ĢL-1 N produced greatest fresh and dry shoot mass, plant height, leaf area, leaf tissue nitrogen, net assimilation rate, relative growth rate and leaf mass ratio. Nitrogen at 90 mg ĢL-1 improved dry root mass, pulling success, specific leaf area and leaf area ratio. Greatest values of root: shoot ratio and root mass ratio were obtained at 0 mg ĢL-1 N. Nitrogen at 90 mg ĢL-1 was best as it produced transplants with more vigorous root growth which pulled out easily from the seedling trays. To determine the best combination of spacing and nitrogen top-dressing for improved cabbage production under local conditions, a field experiment was conducted. Cabbage Copenhagen Market transplants were spaced at 30 x 50 cm, 40 x 50 cm or 50 x 50 cm and fertilized with nitrogen as top-dressing at 50, 100 or 150 kg Ģha-1 N applied in two splits (fourth and eighth week after transplanting). There were no interactions between spacing and nitrogen top-dressing for all measured variables. Nitrogen and spacing did not influence dry matter production and leaf tissue nitrogen. Furthermore, spacing did not affect core height and yield (per unit area) of trimmed cabbage heads. Nitrogen at 100 kg Ģha-1 produced the greatest head mass and yield for untrimmed cabbage heads. The 30 x 50 cm spacing produced the highest yield of untrimmed heads while 50 x 50 cm spacing produced heavier heads. For trimmed heads, 100 kg Ģha-1 N again produced the greatest head mass, head diameter, head height, core diameter and yield. Spacing did not affect the yield for trimmed heads. However, 40 x 50 cm spacing improved head diameter, head height and head mass while core diameter was larger with 50 x 50 cm spacing. The split application of 100 kg Ģha-1 N as top-dressing was best for head mass and yield (per unit area) for trimmed and untrimmed heads. Choice of spacing would depend on whether trimmed or untrimmed heads are targeted.
