Antioxidant,nutritional and anti-nutritional composition of Garcinia kola and Chrysophyllum albidum from rainforest ecosystem of Ondo State,Nigeria

Tropical forests contain many tree species that have supplied edible fruits for centuries.These fruits have contributed to human diets due to their richness in nutrients,vitamins,minerals,antioxidants and their low antinutrients content.We investigated the antioxidant,nutritional and anti-nutritional composition of Garcinia kola and Chrysophyllum albidum fruit parts.The nutritional,anti-nutritional and antioxidant compositions differed depending on the fruit part.Irrespective of fruit part,moisture content was high(72–93 %).While the edible part(fruit pulp) of C.albidum proved a better source of protein(4),fibre(17 %) and fat(2 %),the seed kernel was a better source of ash(2 %) and carbohydrate(15 %).Carbohydrate(22 %),protein(2 %),fat(1 %) and fibre(3 %) were higher in G.kola seed kernel(edible part) than in the pulp and pod.Anti-nutrient content in G.kola and C.albidum fruits was low,indicating that their consumption would not pose nutritional or health problems.The antioxidant compositions(especially phenolic content(10–21 mg g-1) and DPPH(1,1-diphenyl–2 picrylhydrazyl)(26–55 %)) of C.albidum fruit pulp and G.kola seed kernel were high,implying that they could be good sources of natural antioxidants and could be used as supplements in food manufacturing.     

Yields of maize/cassava intercrops grown with hedgerows of three multipurpose trees on an acid Ultisol of Cameroon

Maize/cassava were intercropped between hedgerows of Senna spectabilis [(DC.) Irwin and Barneby], Flemingia macrophylla [(Willd.) Merrill] and Dactyladenia barteri [(Hook f ex Oliv.) Engl.] for five consecutive years on an Ultisol in southern Cameroon. Crop yields and hedgerow biomass production in the third to fifth year of cropping are reported. S. spectabilis produced more biomass than F. macrophylla and D. barteri in all years. Cumulative maize grain and cassava tuber yields were highest in F. macrophylla alley cropping, outyielding the no-tree control consistently by 42 to 67% (average 56%). Between hedgerows of D. barteri and S. spectabilis, crops yielded 17% and 16% more than the no-tree control, respectively. However, between S. spectabilis hedgerows, yields were highly variable between years (–15% to +35% compared to the no-tree control) and thus the system is at risk of failure. F. macrophylla is recommended for continuous alley cropping of maize/cassava intercrop. The use of D. barteri may require fallow phases for biomass accumulation followed by cropping phases with rigorous pruning. Although this may lead to lower cumulative yields, the products of the fallow phase, such as stakes and firewood, may provide some compensation.This revised version was published online in November 2005 with corrections to the Cover Date.     

Growth and yield response of papaya to intercropping with vegetable crops in southwestern Nigeria

At Ibadan, southwestern Nigeria, papaya trees were intercropped with okra, watermelon, sweet potato, bush greens, jews' mallow and Solanum gilo Raddi. The aim of the experiment was to select crops suitable for intercropping in the alleys of papaya plants in orchards. Sweet potato and Solanum gilo Raddi caused marked reduction in the yield of papaya. Land Equivalent Ration (LER) for papaya intercopped with okra, water-melon, sweet potato, bush greens, jews' mallow and Solanum gilo Raddi were 3.86, 3.13, 2.06, 1.86, 1.60 and 1.54, respectively; indicating that all the combinations were more advantageous than the monocrop of papaya. Monetary value of the mixtures, however, indicated that the inclusion of intercrops of sweet potato or Solanum gilo Raddi, is disadvantageous.Although intercropping in papaya orchards is beneficial, it should be limited to the early vegetative and late fruiting phases of papaya when the Leaf Area Index (LAI) of papaya is low. A relay of okra followed by watermelon or bush greens followed by jews' mallow (or sweet potato grown for fodder) is considered suitable for intercropping the alleys of papaya.     

Insect pests of some exotic and indigenous browse species in southeastern Nigeria

During the period February to July 1992 the incidence of attacks by insect pests on ten cultivated browse species was studied at Obio Akpa, located in humid southeastern Nigeria. Two of the browse speciesGliricidia sepium andLeucaena leucocephala were exotic and eightAlchornia cordifolia, Baphia nitida, Rauvolfia vomitoria, Diallum guineensis, Ficus capensis, Glyphaea brevis, Homalium aylmeri andManniophytum fulvum indigenous. Forty insect pests were collected and 33 identified. Those identified belonged to either the order Coleoptera, Heteroptera, Lepidoptera or Orthoptera. Some of the insects were browse-specific, while others attacked several browse species. None of the browse species was free from insect attacks.     

Alley cropping of sorghum with Leucaena during the post-rainy season on Vertisols in semi-arid India

A field experiment was conducted for two years (1989– 1991) on a Vertisol in Bijapur, India in a split-plot design, replicated four times, to evaluate the potential of alley cropping post-rainy season sorghum between Leucaena hedgerows. Leucaena produced on average 2.74 t per ha of prunings and 1.57 t per ha of wood annually. Alley cropping decreased sorghum yields by 28 to 45% when all Leucaena prunings were removed from the system and by 21 to 24%, when on average 1.92 t per ha prunings were applied to the soil annually. The reduction of sorghum yield increased as higher rates of N were applied to sorghum. Although alley cropping increased organic carbon by 21% and available N by 19% at the time of crop sowing, it did not result in increased crop yields because of competition for water between hedgerows and crops. Calculation of land equivalent ratios based on total Leucaena biomass indicated that alley cropping was more productive than sole cropping of sorghum only in one year, and that, too, when no N was applied to sorghum. Therefore, alley cropping of Vertisols with post-rainy season sorghum is not likely to have any advantage in the short term. This revised version was published online in June 2006 with corrections to the Cover Date.     

Financial evaluation of smallholder timber-based agroforestry systems in Claveria, Northern Mindanao, the Philippines

In the Philippines, timber production on small farms has become profitable as a result of reduced supplies due to extensive deforestation and increasing demand. In the early 1990s, when the price of timber was high, farmers were promised huge returns from tree farming. However, widespread planting of few species has led to oversupply and a sharp decline in the price of farm-grown timber. Moreover, low intercrop yields as a result of competition from fast-growing trees and low timber yields due to poor tree management, further reduce net economic returns. In spite of this, interest in tree farming remains high. This paper examines the private profitability of two tree-maize systems, namely trees in blocks and trees in hedgerows, compared with the alternative of maize monocropping. The analysis reveals that maize monocropping provides higher returns to land at the current timber price, but considerably lower returns to labour, than the maize-tree systems tested. This suggests that tree farming is a more attractive option for labour and capital-constrained households or those with off-farm opportunities that compete for their labour. These farmers may raise productivity and income by planting trees on the excess land that cannot be devoted to annual crops. The analysis also indicates that wide-spaced tree hedgerows are superior to tree blocks, due to lower establishment and management costs, longer periods of viable intercropping and more rapid tree growth.     

Cutting management of alley cropped leucaena/gliricidia-Guinea grass mixtures for forage production in southwestern Nigeria

A study was conducted at Fasola (7°45 N and 3°5 E) in southwest Nigeria to determine the best tree cutting scheme for forage production and the effects of hedge configurations on tree, grass and total forage productivity of 6–8-year-old leucaena (Leucaena leucocephala Lam. de Wit) and gliricidia (Gliricidia sepium Walp.)-Guinea grass (Panicum maximum Jacq. cv. Ntchisi) mixture. After a uniform cut at the end of January 1990 (mid-dry season), the trees were cut according to the following cutting regimes: one cut after a 12-month regrowth (12M); two cuts after three- and nine-month regrowth (3–9M); two cuts every six months (6-6M); two cuts after nine- and three-month regrowth (9-3M); three cuts, two cuts every three months and the third cut after a six-month regrowth (3-3-6M), and four cuts every three months (3-3-3-3M). Grass was cut every six weeks between April and October followed by a cut in January. The hedge configuration was either one or three hedgerows of mixed stands of leucaena and gliricidia. There were twice as many trees and one-third less grass in the triple than in the single hedgerow hedge configuration.The 3-3-3-3M, 9-3M and 3-3-6M cutting regimes produced the highest total forage (tree foliage + grass) dry matter yields (DM) of 6.54, 5.80 and 5.77 t DM ha^–1 annum^–1, respectively. The magnitude of the difference between the tree forage yields of the triple and single hedgerow plots (16%) did not reflect the theoretical difference in the number of trees (33%) in the two arrangements.     

Process studies in aPinus radiata-pasture agroforestry system in a subhumid temperature environment. II. Analysis of dry matter yields in the third year

In this paper we analyzed the dry matter yields (DM) produced in an agroforestry trial consisting of pine trees grown over (1) Control (bare ground), (2) ryegrass/clovers (Lolium perene/Trifolium spp.), (3) ryegrass only, and (4) lucerne (Medicago sativa) during the third growing season between 1992 and 1993. In addition these pastures were grown alone in separate plots in the open. The results show that:

Agroforestry for soil and water conservation in the western Himalayan Valley Region of India 2. Crop and tree production

A ten-year-study (1983 to 1992) conducted on nine 15 × 90 m runoff plots at 4% slope compared production efficiency of Leucaena leucocephala and Eucalyptus hybrid based agroforestry as well as monocropping landuse systems in the warm, subhumid climate of the western Himalayan region of India. Treatments for the first sequence were: monocropping systems of leucaena, eucalyptus, Chrysopogon fulvus grass and maize – wheat rotation, and alley cropping systems of grass and crops at 4.5 and 10.5 m alley widths with paired contour tree rows of leucaena and eucalyptus. In the second sequence, alley width increased to 22.5 m in 1989, grass was replaced by turmeric Curcuma longa and paired contour rows of leucaena hedges were introduced in monocropping systems of grain crops and turmeric. Integration of leucaena and eucalyptus trees with crops caused severe reduction of crop yields ranging from 21 to 92% for wheat grain, 59 to 69% for maize grain, 60 to 67% for dry grass and about 50% for turmeric rhizome depending upon the age of trees and alley width. The grain yield of crops stabilized at about 50% reduction with 22.5 m alley width. Total crop biomass (grain + straw) also revealed a similar trend; however, its magnitude of reduction was less severe than for grain. Production of biomass was much lower near the tree rows than in mid alleys. Managing leucaena as contour hedgerows eliminated crop yield reduction in alleys. Performance of grass and turmeric in alleys was not found to be satisfactory. Biomass produced from trees adequately compensated the crop yield reduction. Land equivalent ratios of agroforestry landuses were comparable or even better than monocropping systems indicating suitability of these systems for the western Himalayan valley region. This revised version was published online in June 2006 with corrections to the Cover Date.     

Productivity of hedgerow shrubs and maize under alleycropping and block planting systems in semiarid Kenya

A field experiment was conducted for eight cropping seasons from 1988 to 1991 in semiarid Machakos, Kenya, to compare the productivity of shrubs and crops in intercropping (alleycropping) versus block (sole) planting systems. The study, conducted in a split-plot experiment with three replications, consisted of two tree species (Leucaena leucocephala andSenna siamea syn.Cassia siamea) in the main-plots and combinations of two planting systems (alleycropping and block planting of the shrubs and maize) with five different ratios of land allocation for the shrub and crop (1000, 1585, 2080, 2575, and 0100) in sub-plots. Thus, a sole maize and a sole tree were included in the subplot treatments. The spacing between hedgerows of shrubs in intercropping was 6.7, 5, and 4 m, respectively, corresponding to 15, 20, and 25% land allocation to shrubs. The trees were pruned to 0.5 m height four times a year. Intercropped hedgerows of senna and leucaena produced 10% and 24% more biomass than their respective block planting systems. On average, leucaena produced more biomass than senna. Maize alleycropped with leucaena yielded 16% less grain than sole-crop maize, whereas senna intercropping caused hardly any maize-yield reduction. Compared with the respective sole-crop systems, leucaena intercropping did not affect land equivalent ratio (LER), whereas LER increased by 28% with senna intercropping. The different tree:crop land occupancy ratios did not affect the production of either the component species or of the total system, except that LER declined with incrreased spacing between hedgerows. It is concluded that in semiarid highlands of Kenya, leucaena and crops should better be grown in sole blocks, not in alleycropping. In the case of slow-growing species such as senna, intercropping is worthwhile to consider only if the additional labour needed does not pose a serious problem for management, and the species has fodder value.     

Intercropping system of tropical leguminous species and Eucalyptuscamaldulensis, inoculated with rhizobia and/or mycorrhizal fungi in semiarid Brazil

For the purpose of reforestation and wood supply the leguminous tree Anadenanthera peregrina, a native species, was intercropped with Eucalyptus camaldulensis in a degraded semiarid area of Brazil. Single and mixed stands of these species were inoculated with Rhizobium and/or arbuscular mycorrhizal fungi (AMF). The growth of all species in mixed stands did not differ from those cultivated in monoculture and land equivalent ratio (LER) exceeded unity in intercropped plots. Inoculated plants showed greater height and diameter growth and dry matter and nutrient concentration in plants of A. peregrina was higher in inoculated single plots. The distribution, composition and density of AMF species was related to the rhizosphere effect of plant species. The intercropped model where all the plants were inoculated achieved soil AMF diversity patterns similar to those of the preserved area and showed also higher soil organic matter, nutrient content as well as a reduction in soil macroporosity. This model of intercropping may be considered as an efficient system for reforestation under semiarid conditions.     

Influence of prior land use on wood quality of Pinus radiata in New South Wales,Australia

Wood quality data from 33 sites aged between 15 and 18 years old were analysed to determine the effect of prior land use (pasture, cleared grazing land or timber) on wood density, wood stiffness, fibre length and kraft pulp yield. Sampling sites covered 6 different forest areas within the estate. Prior land use (PLU) significantly affected wood stiffness, density and fibre length but not the kraft pulping traits. In contrast, differences were found between different forest areas for the kraft pulping traits plus fibre length but not for stiffness or density.