Evaluation of five Pecan cultivars [Carya illinoensis (Wang.) R. Koch] for yield, precocity, alternate bearing, leaf:nut ratio and length of growing season in the Transvaal middleveld

Abstract

The average yield of five pecan cultivars over a 22-year period was 25, 1 kg per tree per annum. The extrapolated average yield for the last 10 years of bearing was 2 642 kg ha^-1, which compares favourably with results from the U.S.A. ‘Ukulinga’ was a very precocious cultivar; ‘Moore’ and ‘Mahan’ produced lower though still satisfactory early yields, while ‘Barton’ and ‘Success’ lacked precocity at Roodeplaat. ‘Moore’ and ‘Barton’ were alternate bearers while ‘Ukulinga’, ‘Mahan’ and ‘Success’ produced less fluctuating yields. The genetic factor appeared to have a stronger influence on precocity and yield fluctuations than environmental conditions. The leaf:nut ratio averaged 23 for the five cultivars over a 3-year period, which does not indicate overloading. ‘Success’ was an early maturing cultivar (nut growing season length of 186 days), ‘Moore’, ‘Barton’ and ‘Mahan’ were mid-season cultivars (200–217 days), while ‘Ukulinga’ was a late-season cultivar (253 days). These results indicate that the Transvaal middleveld has potential for commercial pecan production.

Keywords:

• Alternate bearing
• Pecan
• precocity
• yield