| A simple and effective method for the micropropagation and in vitro induction of polyploidy and the effect on floral characteristics of the South African iris, Crocosmia aurea K Hannweg, A Sippel, I Bertling South African Journal of Botany 88, 367-372, 2013 | 35 | 2013 |
| Floral differentiation and development in Carica papaya cultivar ‘Sunrise Solo’ AD Sippel, NJF Claassens, LC Holtzhausen Scientia horticulturae 40 (1), 23-33, 1989 | 21 | 1989 |
| Growth rates of Pinkerton avocado fruit AD Sippel, W Conradie, NJF Claassens South African Avocado Growers' Association Yearbook 15, 72-74, 1992 | 17 | 1992 |
| New cultivars and hybrid selections from the mango breeding program of the Agricultural Research Council in South Africa CF Human, S Rheeder, AD Sippel VIII International Mango Symposium 820, 119-126, 2006 | 14 | 2006 |
| Avocado breeding: a progress report Z BIJZET, AD Sippel, PJJ Koekemoer South African Avocado Growers' Association Yearbook 16, 86-89, 1993 | 14 | 1993 |
| Breeding and evaluation strategy on avocado CP Du Plooy, Z Marais, A Sippel South African Avocado Growers’ Association Yearbook 15, 75-77, 1992 | 11 | 1992 |
| Rootstocks Z Bijzet, AD Sippel The cultivation of avocado. Institute for Tropical and Subtropical Crops ARC …, 2001 | 10 | 2001 |
| Mutation breeding as an effective tool for papaya improvement in South Africa JH Husselman, MS Daneel, AD Sippel, AA Severn-Ellis XXIX International Horticultural Congress on Horticulture: Sustaining Lives …, 2014 | 7 | 2014 |
| Effect of different pollen parents on fruit retention and fruit characteristics in'Wai Chee'litchi IJ Froneman, Z Bijzet, AD Sippel, JP Bower XXVIII International Horticultural Congress on Science and Horticulture for …, 2010 | 7 | 2010 |
| Report on macadamia cultivar performance in Levubu, Tzaneen and Burgershall during the 2002 harvesting season AD Sippel, M Hobson, S Rheeder, D Baloi, G Salaün Southern African Macadamia Growers’ Association Yearbook 10, 11-21, 2002 | 7 | 2002 |
| Use of polyploidy in tropical and subtropical plant improvement programmes K Hannweg, M Penter, A Sippel XXVIII International Horticultural Congress on Science and Horticulture for …, 2010 | 6 | 2010 |
| Avocado fruit maturity (cv. Pinkerton) as affected by fruitset period AD Sippel, MA Holmes, NJF Claassens, V ClAASSENS South African Avocado Growers' Association Yearbook 17, 91-94, 1994 | 6 | 1994 |
| Analysis of ‘Pinkerton’avocado fruit growth AD Sippel, MA Holmes, NJF Claassens, V CLAASSENS South African Avocado Growers’ Association Yearbook 16, 90-95, 1993 | 6 | 1993 |
| A look into the variability of prochloraz residues in the avocado industry MS Daneel, A Sippel, M de Beer, J Mlimi S. Afr. Avocado Growers Assoc. Yearbook 39, 92-98, 2016 | 5 | 2016 |
| Genotypic variation of rind colour in citrus tangor Kiyomi families NK Combrink, Z Bijzet, AD Sippel, M Booyse, MT Labuschagne Acta Hortic 1065, 439-448, 2015 | 5 | 2015 |
| Manipulation of fruit-set period of the'Pinkerton'avocado and its effect on fruit and tree characteristics AD Sippel, MA Holmes, NJF Claasens South African Avocado Growers' Association Yearbook 18, 77-79, 1995 | 5 | 1995 |
| The effect of different seed treatments on germination of Carica papayaL AD Sippel, NJF Claassens Inligtingsbulletin–Instituutvir Tropiese en Subtropiese Gewasse 250, 16-19, 1993 | 5 | 1993 |
| Phrocloraz–A look into factors affecting the variability of residue levels on avocado fruit MS Daneel, A Sippel, MS de Beer, J Mlimi South African Avocado Growers’ Association Yearbook 40, 72-77, 2017 | 4 | 2017 |
| The current status of avocado Phase II evaluations at the ITSC AD Sippel, Z Bijzet, B Snijder, CP Du Plooy South African Avocado Growers' Association Yearbook 17, 67-69, 1994 | 4 | 1994 |
| Expanding genetic diversity of the South African litchi germplasm collection to promote plant improvement IJ Froneman, D Nonyane, A Severn-Ellis, RB Cronje, AD Sippel XXIX International Horticultural Congress on Horticulture: Sustaining Lives …, 2014 | 3 | 2014 |
