Nursery substrates and provenances influence rooting performance of juvenile single-node vine cuttings of Gnetum africanum Welw. (Gnetaceae)
Caspa R; Biloso A; Akalakou C; Mafolo J; Tsobeng A
Gnetum africanum Welw. (Gnetaceae) is a forest vine that is highly valued for its leaves which are a\r\nsource of food and income. Because wild populations are threatened by over-harvesting there is\r\nan increasing need to cultivate the plant which in turn entails a need for developing good quality\r\nplanting material. This study investigates the effects of four provenances four substrates and\r\ntheir interactions on rooting and shoot development of vine cuttings of G. africanum using the\r\nnon-mist propagation system developed by ICRAF. Single-node half-leafed vine cuttings were\r\nused and data on rooting and leaf production were collected monthly from the second to the fifth\r\nmonths. Rooting percentages were subjected to analysis of variance using logistic regression procedures\r\nin Genstat version 12. Provenance (P<0.001) substrate (P<0.001) and interaction between\r\nprovenance and substrate (P<0.001) showed highly significant effects on rooting. Excel was used\r\nto determine rooting percentages with the highest observed in fine sand on cuttings from LekieAssi\r\n(81%) and Boumnyebel (79%) which are high G. africanum exploitation areas in the Centre\r\nRegion of Cameroon. Boumnyebel showed a significantly higher shoot development than the\r\nother provenances. Fine sand and sharp sand can be recommended for rapid low-cost production\r\nof G. africanum planting material.