Shea nuts play an important role in food security for rural folks within sub-Sahara Africa, serving as the main source of income for many people living in Northern Ghana. Unfortunately, the full economic potential of the Sheanut tree has not been fully realized due to the difficulty involved in its domestication. This difficulty in vegetatively propagating sheanut trees has greatly hindered its cultivation and the realization of its true economic potential. Two experiments were conducted to investigate the effects of rooting media and varying indole 3-butyric acid (IBA) concentrations on adventitious root formation in cuttings taken from coppiced sheanut trees. Results indicated that 3000 ppm produced significantly (p < 0.05) better rooting (57.5%) than 5000 ppm (30%), 7000 ppm (45.0%) and the control (7.5%). Although the levels of soluble sugars (SS) and total free phenols (TFP) in the cutting were significantly (p < 0.05) higher at the end of the experiment (after IBA treatment) compared to the start (prior to IBA treatment), the SS and TFP trends observed did not clearly explain the rooting differences found between the IBA levels investigated. Callus formation was significantly (p < 0.05) higher (35.0%) in the control (no IBA). Generally, callus formation decreased with increasing IBA concentration. In the rooting media experiment, rooting was significantly (p < 0.05) higher in the rice husk medium (35.0%) compared to that in the palm fiber (18.3%), saw dust (14.1%) and top soil (16.7%) media.

This study investigated the relationship of stem anatomy to differences in rooting ability between Quercus bicolor Wild. and Quercus macrocarpa Michx. cuttings. Quercus bicolor cuttings were found to have a significantly greater proportion of parenchymatous gaps in the sclerenchyma sheath over a 9-week period compared with Q. macrocarpa cuttings. In Q. macrocarpa, the percentage gap was generally low, coinciding with the low percentage rooting observed in this species. Percentage rooting correlated well (r2 = 0.75) with the percentage parenchymatous gap in the perivascular region of Q. bicolor cuttings. The problems with accepting this relationship as causal are stated in the discussion. Untreated cuttings showed normal stem organization: a dermal tissue system that included the initial stages of phellem formation, a cortex, and a ring of closely arranged vascular bundles in early stages of secondary growth. The locations of the five distinct lobes of the pith were coordinated with the locations of root primordia. Callus growth was first detected in the cortex (i.e., external to the fiber bundles), followed by proliferation within the phloem, opposite the lobes of the pith, 8 to 12 days after cuttings were treated with indole butyric acid (6000 mg·L−1 dissolved in 50% v/v ethanol in water). By 14 to 16 days, root primordia had developed within the proliferative tissue in the secondary phloem. In both species, root primordia penetrated parenchymatous gaps in the fiber sheath directly, the fiber bundles being displaced laterally as the roots increased in size.

No abstract

Three experiments were conducted in a plastic greenhouse at the Sinna Garden of the Crop Science Department of the University of Ghana, Legon, Accra to investigate into pre-sowing treatment (water treatment, growth regulator, and sulphuric acid scarification and water soaking) effects on seed germination and seedling growth of Bauhinia rufescens from October to December, 2011 and January to April, 2012, respectively. The experimental design used was complete randomized design. There were 4 treatments in experiment 1, 7 in experiment 2 and 6 in experiment 3. Each experiment was replicated five (5) times. The results showed that Bauhinia rufescens seeds soaked in hot water at 65 0 C for 60 minutes gave the highest mean germination rate, tallest plant height and highest number of leaves per plant at 49 days after soaking. It also had the widest stem diameter, highest fresh shoot and root weight, highest fresh root and dry root weight and number of roots per seedling. Seeds soaked in 500 ppm Gibberelic acid(GA3) produced the highest number of leaves per plant and tallest plants at 49 DAS. Seeds soaked in 750 ppm GA3 had the highest number of leaves per plant at 49 DAS and highest fresh shoot weight. Seeds soaked in 1000 ppm Promalin differed significantly from 500 ppm GA3 and the control in germination percentage. Seeds soaked in 1000 ppm Promalin differed significantly from 500 ppm GA3 and the control in germination percentage. Acid scarified seeds for 60 minutes plus soaking in tap water for 24 hours differed significantly from the seeds treated withother growth regulator rates plus 24 hours soaking in germination percentage. Acid scarified seeds for 45 minutes plus soaking in tap water for 24 hours had the tallest plant and highest number of leaves per plant at 49 DAS, widest stem diameter, highest fresh shoot and root weight and dry shoot weight. Soaking seeds in hot water at 65 0 C for 60 minutes and/or in acid (H2SO4) for 45 minutes plus soaking in tap water for 24 hours is recommended as pre-sowing treatment for Bauhinia rufescens for maximum mean germination rate and vigorous vegetative growth of seedlings.

Cryptolepis sanguinolenta (Lindl.) Schlt., the main source of cryptolepine alkaloid, is intensively exploited in the wild to treat malaria and Lyme disease. In this study, the influence of four inorganic fertilizers (supplying N, P, K, or NPK) and four growth periods (3, 6, 9, and 12 months after transplanting) on the herb’s root biomass, cryptolepine content and yield, and biological activities were investigated in a pot and field trial. The results showed the application of N (in the form of Urea or NPK) increased root biomass yield, cryptolepine content, and cryptolepine yield compared to unfertilized plants. The 9-month-old plants recorded the maximum cryptolepine content (2.26 mg/100 mg dry root) and cryptolepine yield (304.08 mg/plant), indicating the perfect time to harvest the herb. Plant age at harvest had a more significant influence (50.6–55.7%) on cryptolepine production than fertilizer application (29.2–33.3%). Cryptolepine extracts from 9- to 12-month-old plants had the highest antiplasmodial activity (IC50 = 2.56–4.65 µg/mL) and drug selectivity index (2.15–3.91) against Plasmodium falciparum Dd2. These extracts were also cytotoxic to Jurkat leukaemia cell lines (CC50 < 62.56 µg/mL), indicating the possible use of cryptolepine for cancer management. Growing the herb in the field increased cryptolepine yield 2.5 times compared to growth in a pot, but this did not influence the antiplasmodial activity of the extract. Commercial cultivation of C. sanguinolenta for 9 months combined with N application could be a promising solution to the sustainable use of this threatened medicinal species.

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Clonal propagation of two oak species, Quercus macrocarpa Michx. and Quercus bicolor Willd. was accomplished using a modified container layering technique. The effects of gibberellin (GA4+7) application on stock plant budbreak, as well as the effect of shoot position, stock plant age, and the role of indole butyric acid (IBA) solvents on rooting were investigated. Five hundred parts per million of GA4+7 applied once every fourth day increased budbreak in both Q. macrocarpa and Q. bicolor stock plants. Basal shoots of Q. bicolor from ontogenetically juvenile portions of the stock plant stem rooted 35.7% compared with 1.8% for shoots arising in more distal parts of the stock plant stem. In addition, stock plant age (2-6 years) had no effect on rooting. The effect of the various IBA solvents on rooting in Q. bicolor was 84.3% (98% ethanol), 81.3% (50% acetone), 100% (100% acetone), 28.6% (5% dimethyl sulphoxide-DMSO) and 65% in 10% DMSO respectively; all shoots in this experiment were treated with 10,000 ppm IBA in the respective solvents. IBA dissolved in DMSO treatments resulted in severe apical browning of shoots.

Two experiments were conducted to determine the effect of severe stock plant cutback on rooting in two oak species Quercus bicolor and Quercus macrocarpa using two propagation systems, layering and cuttings. In experiment 1, field grown plants were either cutback leaving a 0.04 m (1.6 in.) stump above soil level or left intact (not cutback) ≈1.7 m (66.9 inches) tall. Shoots arising from cutback treatments and intact plants were layered using a field layering technique and air layering respectively. Results showed significantly higher (p < 0.01) rooting percentages in layered propagules arising from severely cutback plants in both species [≈77% in Quercus bicolor and ≈70% inQuercus macrocarpa] compared with air layered shoots arising from intact plants [1% in Quercus bicolor and 0% in Quercus macrocarpa]. In experiment 2, shoots arising from three stock plant heights (severely cutback 0.04 m, cutback 1 m and intact ≈1.7 m plants) were either etiolated or grown in full light and cuttings rooted in a perlite medium under mist. Of the two species studied, propagule position was found to have no significant effect on rooting in Quercus macrocarpa cuttings, but significantly (p < 0.0001) influenced rooting in Quercus bicolor. Rooting was highest 59.3% in cuttings taken from cutback-etiolated stock plants. Comparing just the three cutback levels, rooting was highest (45.2%) in cuttings arising from 0.04 m stumps followed by those from 1 m stumps 7.5% and lastly intact plants 3.8%. The best rooting results were observed in shoots arising from severely cutback stock plants (0.04 m) using the field layering technique.