Effect of seedling fibrous roots on field performance of hybrid coffee varieties

Abstract

The objective of this study was to evaluate the effect of number of fibrous roots per seedling on plant growth and yield components of hybrid coffee varieties. A split plot experiment in a randomized complete block design (RCBD) with three replications was used. The main factor consisted of five varieties (N39-2, N39-3, N39-7, KP423-1 and KP423-2) whereas the sub-factor consisted of four types of roots (seedlings with 1-9 fibrous roots; seedlings with 10-17 fibrous roots; seedlings with ≥ 18 fibrous roots and control). Plants were evaluated for vegetative growth and yield components 14 months from the date of planting. The data were subjected to analysis of variance using CoStat software version 6.311 and treatment means were separated based on Tukey's test at P ≤ 0.05. Results indicate that coffee varieties N39-3, KP423-1 and KP423-2 were significantly (P = 0.00) taller than varieties N39-1 and N39-7 while coffee variety N39-2 significantly produced a larger number of fruit clusters per plant (P = 0.00) and higher seed yield (P = 0.00) than the rest of coffee varieties. Results also show that seedlings with at least 18 fibrous roots per seedling highly significantly increased plant height (P = 0.00), stem internode length (P = 0.00), number of fruit bearing primaries per plant (P = 0.00), number of fruit clusters per plant (P = 0.00), number of berries per plant (P = 0.00) and total seed yield (P = 0.00) of hybrid coffee varieties. The interactions between variety N39-3 and seedlings with at least 18 fibrous roots per seedling only significantly increased (P = 0.00) the internode length compared with the interaction between variety N39-3 and seedlings with 10-17 fibrous roots per seedling, and variety KP423-2 and seedlings with 1-9 fibrous roots per seedling. It is concluded that coffee growers should use seedlings with at least 18 fibrous roots per seedling in order to increase plant growth and total seed yield of improved hybrid coffee varieties. Further studies are required to determine propagation technologies which can increase the number of fibrous roots to at least 18 per stem cutting of hybrid coffee varieties.