Objective: The objective of this study was to evaluate the effect of different rootstocks on graft success of Tanzanian local tomato cultivars. Eggplant rootstocks (EG190, EG195, EG203 and EG219, and tomato rootstock (Hawaii 7996) were obtained from AVRDC in Taiwan while local tomato cultivars (Tengeru 97, Tanya, Cal-J and Riogrande) were sourced locally. Methodology and Results: Cleft graft method was carried out when seedlings of eggplant, Hawaii 7996 and local tomato cultivars were 30, 17 and 14 days old, respectively. The grafted seedlings with graft union tied using grafting clips were healed in a dark chamber for three days and then in a transparent chamber for three days. The average temperature and relative humidity in both chambers were maintained at 21-30°C and 85-95 %, respectively. The grafted seedlings were hardened for seven days in an open nursery with 30% overhead shade prior to transplanting. Data on graft success were subjected to analysis of variance using MSTATC statistical software and treatments mean separation was conducted based on Student-Newman Keuls at P < 5 %. Results show that graft success between eggplant rootstocks and local tomato cultivars was higher ranging from 86 to 100%. On the contrary, grafting rootstock Hawaii 7996 with local tomato cultivars significantly (P≤ 5%) resulted in a lower graft success ranging from 30 to 50% during the hardening stage in the open nursery. Conclusion and application of results: Tanzanian local tomato varieties can be grafted onto eggplant rootstocks EG190, EG195, EG203 and EG219 with high graft success. As these eggplant rootstocks are resistant to soil borne diseases, farmers should graft their varieties in order to increase tomato yield. Further studies are therefore required to optimize the grafting conditions to improve graft success between rootstock Hawaii 7996 and local tomato cultivars.

The fruits of Msasa and Jaffa orange varieties were harvested and subjected to post-harvest treatments namely; dipping in hexanal, dipping in calcium chloride and compared with untreated control; and they were stored at ambient (28 ± 2°C) and reduced temperatures (18 ± 2°C) conditions. Data were collected on the 0, 4 th , 8 th , and 12 th days from the date of fruit harvest. Chemical analyses were conducted to determine vitamin C content, total sugars, reducing sugars and total flavonoids. Post-harvest treatments had a significant effect on vitamin C and total flavonoids of Jaffa orange fruit. Hexanal treated fruit had higher values of total flavonoids, vitamin C, and total sugars compared to calcium chloride treated and control fruit. The storage durations showed significant effects on the vitamin C content of Jaffa, total flavonoids, the total and reducing sugars of both fruit varieties. Vitamin C and total flavonoids decreased with increasing storage duration of fruit. The significant interactions of factors were observed on total sugar which was increasing with increasing storage duration, but higher in hexanal treated and ambient stored fruit. Based on consumer acceptance test, the hexanal treated fruits were the most liked followed by calcium chloride treated and untreated fruits based on the appearance, taste, texture and overall acceptability.

However, the response of cv. "Itoke Sege" to in vivo macropropagation combined with different benzylaminopurine (BAP) concentrations is not known. This study was conducted to determine the appropriate concentration of BAP for enhancing in vivo macropropagation of French plantain cv. 'Itoke Sege'. Methodology and results: Sword suckers of about 70 -80 cm tall and 14 -16 cm collar diameter were obtained from farmers' fields in Rungwe district in Mbeya, Tanzania. Moistened sawdust was steamsterilized for 45 minutes and then filled for cooling in wooden propagators of 1.5 m x 2.20 m x 0.3 m dimension. Suckers were partially peeled, washed to remove roots and surface-sterilized for 15 seconds by dipping them in hot boiling water. The sterilized corms were desheathed to expose axillary buds and decorticated to suppress the apical meristems. Fifteen corms in three replications were each dipped in BAP at 0.0, 1.5, 3.0 and 6.0 mg/l for 12 hours and then planted into sawdust media. Irrigation was done immediately but subsequent watering was carried out when necessary. In vivo multiplication response was evaluated based on number of days to first shoot emergence, number of shoots per corm, number of roots per shoot and shoot size. Results showed that BAP concentration at 1.5 mg L -1 significantly (P < 0.05) reduced the number of days to first shoot emergence of 15.78 days followed by BAP at 3.0, 6.0 and 0.0 mg L -1 with 25.18, 28.39 and 36.43 days, respectively. Similarly, BAP concentration at 1.5 mg L -1 significantly (P < 0.05) increased sucker productivity with 17.11 suckers per corm followed by BAP at 0.0, 3.0 and 6.0 mg L -1 with 15.23, 13.08 and 12.96 suckers per corm, respectively. Corms treated with BAP at 1.5, 3.0, 6.0 mg L -1 significantly (P ≤ 0.05) produced taller shoots with length of 27.0, 27.3 and 26.7 cm followed by corms treated with BAP at 0.0 mg L -1 with shoot length of 22.7 cm. Conversely, corms treated with BAP at 0.0 and 6.0 mg L -1 produced suckers with larger collar diameter of 3.4 and 2.4 cm followed by suckers from corms treated with BAP at 3.0 and 1.5 mg L -1 with collar diameters of 2.2 and 2.0 cm, respectively. Suckers from corms treated with BAP at 0.0 and 3.0 mg L -1 had larger number of leaves of 4.8 and 4.6 per sucker followed by suckers from corms treated with BAP at 1.5 and 6.0 mg L -1 with 4.0 and 3.8 leaves per sucker, respectively. Conclusion and application: Based on these findings, it is concluded that in vivo macropropagation combined with BAP at 1.5 mg L -1 is a suitable technique for improving multiplication and sucker growth of French plantain cv. 'Itoke Sege'. The findings of this study provide an opportunity for the use of in vivo macropropagation coupled with BAP at 1.5 mg L -1 as an alternative simple and cheap technology for rapid and mass production of planting materials for recalcitrant plantain varieties. Further study is recommended to evaluate the response of cv. "Itoke Sege" to in vivo macropropagation combined with other cytokinebased growth regulators. Research is a...

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