Allelopathic Effects of Sweet Basil (Ocimumbasilicum L.) on Seed Germination and Seedling Growth of some Poaceous Crops

Laboratory and greenhouse experiments werecarried out at the Faculty of Agricultural Sciences, University of Gezira, Sudan in season 2014/15 to study the allelopathic effectsof aboveground parts ofsweet basil (Ocimumbasilicum L.) on seed germination and seedling growth of some poaceous crops.Laboratory experiments were conducted to study the allelopathic effects of aqueous extract of aboveground parts ofsweet basilon seed germination of sorghum (Sorghum bicolor [L.] Moench), millet (Pennisetumglaucum [L.]R. Br.), maize (Zea mays L.) and wheat (TriticumvulgareL.).Six concentrations (0, 20, 40, 60, 80 and 100%) of the aqueous extract of the aboveground parts of sweet basilwere prepared from the stock solution(50 g / l). Treatments, for each crop, were arranged in completely randomized design with four replicates. The seeds were examined for germination at three days after initial germination.Greenhouse experimentswere conducted to study the allelopathic effects of powder of aboveground parts ofsweet basil on seedling growth of the same poaceous crops. The powder of aboveground parts was incorporated into the soil at rate of 0, 1, 2, 3, 4 and 5% on w/w bases in pots. Treatments, for each crop, were arranged in completely randomized design with four replicates. The experiments were terminated at 30 days after sowing and the plant height, number of leaves and root length of crop seedlings were measured as well as plant fresh and dry weight.Data were collected and subjected to analysis of variance procedure. Means were separated for significance using Duncan`s Multiple Range Test at p 0.5. The results showed that the aqueous extract of aboveground parts of sweet basil significantly reduced seed germination of the tested poaceous crops and there was direct negative relationship between concentration seed germination. Also, the results showed that incorporating powder of aboveground parts into the soil significantly decreased plant height and root length of crop seedlings as well as seedling fresh and dry weight. In addition, the reduction in seedling growth was increased as the powder increased in the soil. Based on results supported by different studies, it was concluded that sweet basil has allelopathic affects on seed germination and seedling growth of the poaceous crops

Growth performance of two lemon [Citrus limon (L.) Osbeck] cultivars budded on three rootstocks, Gezira State, Sudan

     Lemon [Citrus limon (L.) Osbeck ], family Rutaceae, is one of the world's major fruit crops with global popularity contributing to human diets. Lemon rootstocks and scion cultivars play an important role in the rapid development of citrus in the world. This study was conducted to evaluate the growth performance of two lemon cultivars budded on three rootstocks under Gezira State conditions, Sudan. The experiment was conducted in the nursery of the Department of Horticultural Sciences, Faculty of Agricultural Sciences, University of Gezira, Wad Medani, Sudan, in 2017.Volcamariana, Rough Lemon and Macrophylla rootstocks were grafted with buds of Eureka and Teresa cultivars. The T- budding technique was used in this study. Treatments were arranged in a randomized complete block design with three replicates. Parameters measured were rootstock height and thickness, height of scion, number of branches, length of branches and stem circumference of the scion. The parameters were recorded for 10 months.  Rootstocks were significantly different in their vegetative growth.  Rough Lemon rootstock resulted in the best vegetative growth.  However, there were no significant differences in growth parameters between Volkameriana and Macrophylla rootstocks. Lemon cultivars were highly significantly different in their vegetative performance. Teresa lemon cultivar resulted in the largest plant height (73.9 cm), number of branches (27), length of branches (68 cm) and stem circumference (11.8 cm). The interaction effects of rootstocks and cultivars on vegetative performance of lemon were significant. The largest plant height (84.33 cm), number of branches (31.7), length of branches (75.7 cm) and stem circumference (12.3 cm) were obtained by Teresa cultivar budded on Rough Lemon rootstock and the smallest parameters were obtained by Eureka cultivar budded on Volkameriana, whereas the smallest length of branches (55.3) and stem circumference (9.5 cm) were obtained by Eureka cultivar budded on Macrophylla. Depending on the results of this study, it is recommended to bud the lemon cultivar Teresa on Rough Lemon rootstock under Gezira State Conditions, to obtain the best growth performance