Effect of planting date, seed rate and method of planting on growth, yield and quality of black cumin (Nigella satira) in Khartoum State [Sudan]

This study was carried out in Shambat area at the Demonstration Farm of the Faculty of Agriculture, University of Khartoum and Horticultural Research Station for two growing seasons of 1993/94 and 94/95 respectively. The objectives of the study were to investigate and determine the optimun sowing date, seed rate and planting method of black cumin (Nigella sativa) under prevailing environmental conditions of Khartoum area. Three independent experiments were conducted to study the effect of these agronomic practices on plant growth, seed yield and yield components. In experiment (1) sowing date treatments were: lst, 15th of November; lst, 15th oof December; lst and 15th of January in the season 1993/94 and the same treatments with the exception of 15th of January in the season 1994/95. In experiment (2) seed rate treatments were : 3.2, 6.4 and 9.6 kg/fed in both seasons. In experiment (3) planting method treatment were: broadcasting holes 20 cm apart and drilling method in the two seasons. Data collected and analysed were the same in the three experiments and included: number of days to start of seedling emergence, 50 flowering and harvest, plant height, fresh and dry weight per plant, number of branches per plant, number of flowers per plant, number of bods per plant, number of seeds per pods and aborted flowers percentage, thousand seed weight, seed yield per feddan and oil content of seed. The results indicated no consistent difference in days taken to beginning of seedling emergence among sowing dates in the two seasons. However, days to 50 of flowering were less in late sowing, and crop growth vigor was reduced with delayed sowing date. Percentage of empty pods and aborted flowers increased with delaying in sowing date. Results showed statistically significant effect of sowing date on seed yield. Fifteenth and first of November sowing gave the higher seed yield in the season 93/94 and 94/95, while non-significant reduction in seed yield was detected from lst of December till lst of January; however the results of season 93/94 were inconclisive due to missing data of seed yield for the sowing dates of 15th December, lst and 15th January. Sowing date was not shown to affect the oil content of seed. Increasing seed rate inversely affected plant height, plant growth vigor and yield components per plant, whereas the seed yield per feddan responded positivelv to increasing seed rate. Drilling method produced longest plants in the two seasons, while the highest growth vigor and yield components per plant resulted from broadcasting method. Braadcasting method praduced significantly the highest thousand seed weight and seed yield in the first season while in the second season drilling method gave the highest values which were not signifcant. Results indicated that suitable planting method depends to a large extent on the type and structure of soil.