Response of yield and yield components to reciprocal grafting in some sweetpotato [Ipomoea batatas (L.) Lam.] clones. (104)
Keywords:Sweetpotato, Yield, Yield components, Reciprocal grafting
AbstractA reciprocal grafting study involving six clones of sweetpotato (Ex-lgbariam, TIS.87/0087, TIS.2532, OP.1.13, CIP 4400168, TIS.86/0356, and TIS.2544 Rusanya 1.5) was carried out during the wet season of 2003. The aim of the study was to look at the relationship between some yield components and the total tuber yield as influenced by the source potentials and sink capacities. The treatments numbering 36, included 6 self-grafts, and were distributed to the plots using the randomized complete block design with 4 replications. The highest mean stock effect on mean number of tubers per plant, tuber girth, and total tuber yield was observed in Clone TIS.2544 Rusanya 1.5. Clone CIP 4400168 showed the highest mean scion effect on tuber girth, mean tuberous root weight, and total tuber yield. Average number of tubers per plant, tuber length, tuber girth, and tuberous root weight per plant were positively correlated with total tuber yield with correlation coefficients of 0.638**, 0.165, 0.545**, and 0.356*, respectively. Results showed that there were differences in the source potentials and sink capacities of the six clones used. Clone TIS.2544 Rusanya 1.5 with a large sink capacity bad a poor source potential, while Clone CIP 4400168 with a high source potential was limited by a poor sink capacity. Selection for clones with large sink capacities and ideal degree of response of sink to a good source, could lead to improvement of yield of sweetpotato through increase in the number and size of tubers.