Sudac-K, A Cultivar for Narrow Row Cultivation in the Sudan Gezira
Jul 31, 2018
At the Gezira Research Station, Wad Medani, Sudan, a field study was initiated in 1996 to determine the response of morphologically contrasting upland cotton cultivars to different row widths and within-row spacing. Sudac-K is a newly synthesized okra-leaf type, resistant to whitefly (Bemisia tabaci Genn.) and is claimed to produce less sticky cotton than the normal-leaf type, Barac (67) B, which is hairy and bushy, forming a closed canopy that favours whitefly infestations. In this study, a relatively narrow row (60-cm) was tested against the conventional check (80-cm). Single-seeding at within-row spacing of 15 and 10 cm were compared against the conventional hill-dropping (3 plants/hill) at within-row spacing of 45 and 30 cm. Data accumulated over two seasons showed that Sudac-K had a lower LAI than Barac (67)B throughout the growing season. The two cultivars, averaged over all other treatments, did not differ significantly in seed cotton yield. However, Sudac-K responded favourably to the 60-cm rows. Yields from single-seeding was significantly higher than that from hill-dropping at the same plant population. The okra-leaf trait, as an average of row widths and within-row spacing, caused a significant reduction in the numbers of whiteflies and consequently in the degree of stickiness. Thus the expected superiority of Sudac-K can manifest itself in several ways: increased yield under high planting density, improved marketability of less sticky cotton and reduced insecticides expenditures.