Dry matter accumulation, distribution and fresh tuber yield of grafted accessions of Hausa potato

The Hausa potato is a minor tuber crop with nutritional and medicinal values. A lack of balance between the photosynthetic source potential and the sink capacity in terms of dry matter accumulation and distribution is believed to affect fresh tuber yield. This study was aimed to investigate the dry matter production, distribution and tuber yield of reciprocal grafts of some accessions of the Hausa potato. The grafts were made in all possible combinations and laid out using the completely randomized design in four replicates. Results showed that harvest index increased with time in most of the grafts. The proportion of dry matter partitioned to the tubers was generally lower than those of the leaves and stems in all the grafts. The highest rootstock-scion ratio of 0.97 was observed in the graft Bokkos 2 - Manchok 2 while the lowest (0.07) was observed in the self-graft of Bokkos 2. Fresh tuber yield was generally low, ranging from 0.03 t ha -1 to 0.09 t ha-1. Apart from dry matter accumulation and distribution, the relationship between the source potential and sink capacity as well as the rate of translocation of assimilates from the photosynthetic source to the sink need to be investigated.