The objective of this study was to evaluate the effect of different growth media on rooting of stem cuttings of hybrid coffee varieties. The experiment was conducted on-station under a shade house at Tanzania Coffee Research Institute (TaCRI) from October 2013 to February 2014 using a split plot experiment in a Randomized Complete Block Design (RCBD) with four replications. The main factor consisted of five hybrid coffee varieties (KP423-1, KP423-2, N39-3, N39-2 and N39-7) and the sub-factor consisted of five types of rooting media (red soil, peat moss, decomposed saw dust, rice husk and forest soil + fine sand 2:1 (v/v) as a control). The stem cuttings were planted in each type of the media and four months after planting, the cuttings were evaluated based on number of rooted cuttings, total number of roots per cutting, number of lateral roots per cutting and root length. The data were subjected to analysis of variance using CoStat software and treatment means were separated based on Tukey's test at P ≤ 0.05. Results indicate that coffee varieties N39-2 and N39-3 produced the highest rooted stem cuttings of 64.2 and 63.9% respectively. Results also show that red soil media provided the highest rooted stem cuttings of 77.9% followed by sawdust with 68.0%. It is recommended that propagators should use red soil as a rooting media for improving rooting percentage of stem cuttings from improved coffee varieties. Further studies are required to improve chemical and physical properties of red soil media.

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.

The study was conducted on-station at Tanzania Coffee Research Institute to evaluate the effect of stem cuttings position along the mother plants on rooting of hybrid coffee varieties. Stem cuttings were assessed in a rooting medium of forest soil and sand at a ratio of 2:1 by volume under semi-controlled environment. A split plot experiment in a randomized complete block design with four replications was used. The main factor was five Arabica coffee varieties and the sub-factor consisted of four types of position of stem cuttings, namely base, middle, apex and control (mixture). Four months after planting, stem cuttings were evaluated for root growth characteristics. Data collected were subjected to analysis of variance (ANOVA) using CoStat software and treatment means were separated based on Tukey's test at (P ≤ 0.05). Results obtained indicate that positions of stem cuttings along the mother plant had a significant effect (P = 0.04) on rooting of coffee varieties with stem cuttings taken from basal and middle positions having the highest rooting percentage with varieties N39-1 and KP423-2 having the highest rooting percentage. Further, interaction between varieties and position of stem cuttings significantly (P = 0.04) affected the rooting percentage and the number of lateral roots at (P = 0.01). The results from this study indicate that clonal multiplication of coffee stems cuttings is affected by varieties and position taken along the mother plant. Further studies are required to determine yield performance of the stem cuttings in relation to their positions along the mother plants.