Influence of Tangelo (Citrus reticulata X Citrus paradisi) varieties and population density on scion growth in the nursery
Rough lemon (Citrus jambhiri Lush.) rootstocks were planted in citrus nursery at Ibadan to determine the best population density and the most compatible scion for good citrus nursery management practices. Rough lemon rootstock seedlings were planted at population densities of 62,500plants/ha (40cmX40cm), 83,333plants/ha (40cmX30cm), 111,111plants/ha (60cmX15cm), 55,555plants/ha (60cmX30cm single row spacing), 74,074 plants/ha (60cmX30cm double row spacing). These were later budded with three Tangelo (Citrus reticulata X Citrus paradisi) varieties namely: Orlando, Ortanique and Nocatee. The experiment was a randomized complete block design in split plot layout. Data collected were subjected to analysis of variance procedure and means were separated using LSD. Results showed that Nocatee had significantly (p=0.05) superior budtake (93.6%) than either Orlando or Ortanique, while Orlando had the least (73.5%). Ortanique had longest scion length (27.36cm “ 48.20cm) and stem diameter (0.38cm “ 0.74cm) than those of Orlando and Norcatee. Orlando had significantly superior number of leaves (30 “ 70) than those of Ortanique and Nocatee through out the period of study. Scions on rootstock grown at population density of 55,555plants/ha had significantly (P<0.05) higher number of leaves (46-86) and stem diameter (0.52cm-0.83cm) than other population densities during the period of study. While the least number of leaves was obtained in plants grown at 111, 111 plants/ha density, plants at 83,333/ha had the least stem diameter. Length of scions grown at population densities of 111,111 plants/ha was higher than those of other population densities. The study revealed that Nocatee ranked best for budtake, Orlando was best for number of leaves while Ortanique was outstanding for scion length and stem diameter. However, since improvement in scion length and stem diameter are the preferred growth attributes in citrus nursery, Ortanique on rough lemon rootstock performed better than other scions. Also, Population densities of 55,555plants/ha ranked best for most of the parameter measured in this study. .
Keywords: Rough-lemon rootstock, Tangelo scion, population-density