Fruiting Trees Research Articles

Beyond vegetative propagation of indigenous fruit trees: case of Dacryodes edulis (G. Don) H. J. Lam and Allanblackia floribunda Oliv.

Indigenous fruits/nuts of Africa’s humid tropics are increasingly being recognized for their contribution to food security, health (nutrition/medicine), income generation, employment and environmental benefits. However, cultivation of the trees yielding these fruits/nuts is constrained by lack of improved planting materials that are true-to-type and have a short enough juvenile phase to fruit production. In addition, information on both above and belowground growth attributes of these species is scarce. This paper presents an overview of the results of a doctoral research fo- cused on two African indigenous fruit tree species, i.e. Dacryodes edulis (G. Don) H. J. Lam (Burser- aceae) and Allanblackia oribunda Oliv. (Clusiaceae), which are currently under domestication. For D. edulis, the objective was to assess and compare the structural and ne rooting systems together with the above ground growth attributes of fruiting trees propagated either sexually or vegetatively. The research aim for A. oribunda was to shorten the long juvenile phase before first fruiting through grafting techniques. In summary, the results from the studies on D. edulis suggest that vegetative propagation of the species, reduces the long juvenile phase to fruiting and maintains trueness in the transfer of desirable traits over generations, it also results in trees that are apparently less competitive for below ground resources, have more stable root system, and are bigger in stature and higher in carbon sinks compared to trees of seed origin. In parallel, A. oribunda was shown to be amenable to grafting both under nursery and field (in situ) conditions. Furthermore, a grafted A. oribunda tree transplanted in the field in 2007, flowered and carried a single fruit to maturity after 4 years, thereby reducing the long juvenile period to first fruit production from about 10-12 years reported in literature to less than 5 years. The findings of this doctoral research are therefore pertinent to efforts towards indigenous fruit/nut tree domestication. However, research should be confirmed as it can be considered a pilot study, one that aims to obtain insights into the effect of vegetative propagation methods on above and below ground growth and development of improved planting materials of D. edulis and A. oribunda under domestication.Key words: carbon sequestration, cuttings, diversification, domestication, vegetative propagation

Chemical and biological study of Manilkara zapota (L.) Van Royen leaves (Sapotaceae) cultivated in Egypt

Background:Manilkara zapota (L.) Van Royen is an evergreen tree, native to the tropical Americas and introduced to Egypt as a fruiting tree in 2002. No previous study was reported on the plant cultivated in Egypt.Materials and Methods:In this study, the leaves of the plant cultivated in Egypt were subjected to phytochemical and biological investigations. The lipoidal matter was analyzed by GLC. Five compounds were isolated from the petroleum ether and ethyl acetate fractions of the alcoholic extract of the leaves by chromatographic fractionation on silica gel and sephadex, the structures of these compounds were identified using IR, UV, MS, 1H-NMR and 13C-NMR. The LD50 of the alcoholic and aqueous extracts of the leaves was determined and their antihyperglycemic, hypocholesterolemic and antioxidant activities were tested by enzymatic colorimetric methods using specific kits.Results:Unsaturated fatty acids represent 32.32 % of the total fatty acids, oleic acid (13.95%), linoleidic acid (10.18 %) and linoleic acid (5.96 %) were the major ones. The isolated compounds were identified as lupeol acetate, oleanolic acid, apigenin-7-O-α-L-rhamnoside, myricetin-3-O-α-L-rhamnoside and caffeic acid. This is the first report about isolation of these compounds from Manilkara zapota except myricetin-3-O-α-L-rhamnoside, which was previously isolated from the plant growing abroad. The LD50 recorded 80 g/Kg b. wt. for both the tested extracts, so they could be considered to be safe. They exhibited antihyperglycemic, hypocholesterolemic and antioxidant activities.Conclusion:The observed biological activities were attributed to the different chemical constituents present in the plant mainly its phenolic constituents.

Palms, peccaries and perturbations: widespread effects of small-scale disturbance in tropical forests

BackgroundDisturbance is an important process structuring ecosystems worldwide and has long been thought to be a significant driver of diversity and dynamics. In forests, most studies of disturbance have focused on large-scale disturbance such as hurricanes or tree-falls. However, smaller sub-canopy disturbances could also have significant impacts on community structure. One such sub-canopy disturbance in tropical forests is abscising leaves of large arborescent palm (Arececeae) trees. These leaves can weigh up to 15 kg and cause physical damage and mortality to juvenile plants. Previous studies examining this question suffered from the use of static data at small spatial scales. Here we use data from a large permanent forest plot combined with dynamic data on the survival and growth of > 66,000 individuals over a seven-year period to address whether falling palm fronds do impact neighboring seedling and sapling communities, or whether there is an interaction between the palms and peccaries rooting for fallen palm fruit in the same area as falling leaves. We tested the wider generalisation of these hypotheses by comparing seedling and sapling survival under fruiting and non-fruiting trees in another family, the Myristicaceae.ResultsWe found a spatially-restricted but significant effect of large arborescent fruiting palms on the spatial structure, population dynamics and species diversity of neighbouring sapling and seedling communities. However, these effects were not found around slightly smaller non-fruiting palm trees, suggesting it is seed predators such as peccaries rather than falling leaves that impact on the communities around palm trees. Conversely, this hypothesis was not supported in data from other edible species, such as those in the family Myristicaceae.ConclusionsGiven the abundance of arborescent palm trees in Amazonian forests, it is reasonable to conclude that their presence does have a significant, if spatially-restricted, impact on juvenile plants, most likely on the survival and growth of seedlings and saplings damaged by foraging peccaries. Given the abundance of fruit produced by each palm, the widespread effects of these small-scale disturbances appear, over long time-scales, to cause directional changes in community structure at larger scales.

Fungi associated with die-back symptoms of apple and pear trees, a possible inoculum source of grapevine trunk disease pathogens

A survey was undertaken on apple and pear trees in the main pome fruit growing areas ofthe Western Cape of South Africa to determine the aetiology of trunk diseases with specific reference to pathogens known to occur on grapevine, which are frequently cultivated in close proximity of these orchards. Several fungal genera containing known trunk disease pathogens were found. Two Diplodia species, D. seriata and Diplodia sp., were isolated along with Neofusicoccum australe and N. vitifusiforme . Four Phaeoacremonium species, Phaeoacremonium aleophilum , Pm. iranianum , Pm. mortoniae and Pm. viticola , two Phomopsis species linked to clades identified in former studies as Phomopsis theicola and Phomopsis sp. 7, and Eutypa lata were found. In addition, Paraconiothyrium brasiliense , Pr. variabile and a Pyrenochaeta like species were also isolated. Diplodia seriata (56% of total isolates) and Pm. aleophilum (22%) were most frequently isolate. First reports from pear wood include the Phaeoacremonium spp. and Paraconiothyrium brasiliense , while new reports from apple include Pm. aleophilum , Ph. theicola , Phomopsis sp. 7, Pr. variabile and E. lata . A pathogenicity trial was undertaken to determine the role of these species on apple, pear and grapevine shoots. Neofusicoccum australe caused the longest lesions on grapevine shoots, while Pr. variabile , D. seriata , Pm. mortoniae and the Pyrenochaeta -like sp. caused lesions that were longer than non-inoculatedand non-pathogen experimental controls. On pear shoots, Diplodia sp. and N. australe caused the longest lesions,followed by D. seriata and E. lata . On apple shoots, the longest lesions were caused by N. australe and Pm. iranianum . These results demonstrate that apple and pear trees in Western Cape orchards are hosts to many known trunk pathogens along with potential new trunk disease-causing fungi.

Laurel Wilt, Caused by Raffaelea lauricola, is Confirmed in Miami-Dade County, Center of Florida's Commercial Avocado Production.

Laurel wilt, caused by Raffaelea lauricola, threatens native and nonnative species in the Lauraceae in the southeastern United States, including the important commercial crop, avocado, Persea americana (2,4). Although the pathogen's vector, Xyleborus glabratus, was detected in Miami-Dade County, FL in January 2010, laurel wilt had not been reported (4). In February 2011, symptoms of the disease were observed on native swampbay, P. palustris, in Miami-Dade County (25°72'N, 80°48'W). Externally, foliage was brown, necrotic, and did not abscise; internally, sapwood was streaked with dark gray-to-bluish discoloration; and, in dead trees, holes of natal galleries of the vector from which columns of frass were attached were evident. On a semiselective medium for R. lauricola, a fungus with the pathogen's phenotype was isolated from symptomatic sapwood. Colonies were slow growing, light cream in color, with dendritic, closely appressed mycelium and often a slimy surface. A representative strain of the fungus was further identified with PCR primers for diagnostic small subunit (SSU) rDNA (1) and its SSU sequence (100% match, GenBank Accession No. JN578863). In each of two experiments, plants of 'Simmonds' avocado, the most important cultivar in Florida, were inoculated with three strains of the fungus, as described previously (3). Symptoms of laurel wilt developed in all inoculated plants and the fungus was recovered from each. After aerial and further ground surveys, additional symptomatic swampbay trees, some of which had defoliated, were detected in the vicinity of the original site. Since swampbay defoliates only a year or more after symptoms develop (4), the 2010 detection of X. glabratus may have coincided with an undetected presence of the disease. As of July 2011, a 6-km-diameter disease focus was evident in the area, the southernmost edge of which is 5 km from the nearest commercial avocado orchard. In August 2011, a dooryard avocado tree immediately north of the above focus was affected by laurel wilt, and an SSU sequence confirmed the involvement of R. lauricola (GenBank Accession No. JN613280). The outbreak of laurel wilt in Miami-Dade County represents a 150 km southerly jump in the distribution of this disease in the United States ( http://www.fs.fed.us/r8/foresthealth/laurelwilt/dist_map.shtml ) and is the first time this disease has been found in close proximity to Florida's primary commercial avocado production area. Approximately 98% of the state's commercial avocados, worth nearly $54 million per year, are produced in Miami-Dade County. Since effective fungicidal and insecticidal measures have not been developed for large, fruit-bearing trees, mitigation efforts will focus on the rapid identification and destruction of infected trees (3,4).

Sustainable forest management: heritage tourism, biodiversity, and upland communities in the Philippines

This paper discusses sustainable forest management in the context of forest-based tourism in the Philippines. Integrating heritage tourism in the implementation of forest management is paramount because the quality and sustainability of nature tourism depend on the ecological integrity of forests. The role of tourism in achieving the goals of sustainable forest management is crucial especially in countries such as the Philippines where the demands for forest resources for tourism and other purposes have been increasing. The tourism management strategies to achieve sustainable forest management in the Philippines include establishing recreational zones within protected forests; using different native fruit-bearing trees in reforestation to attract diverse wildlife, which is a drawcard in tourism; prohibiting illegal collections of threatened forest species for souvenirs; enhancing the tourism and conservation values of botanic gardens within forest reserves; providing supplementary livelihoods to upland dwellers via agroforestry projects; and respecting the culture and practices of indigenous upland people while supporting their economic and traditional subsistence.

Response of watersprout growth to fruit load and intensity of dormant pruning in peach tree

Watersprout occurrence and growth were investigated over a two-year period in an early maturing peach cultivar (Alexandra) under different intensities of dormant pruning for fruited and defruited trees. A preliminary study focused on identifying the laws that determine the probability of presence and occurrence of watersprouts in relation to watersprout-bearing shoot (WBS) length. The increase in watersprout probability of presence and occurrence resulting from greater WBS length illustrated the high capacity of peach for sprouting. Watersprout lengths were measured, as well as the lengths of young shoots, one-year-old fruit-bearing shoots (FBSs) and older branches considered as WBS in order to evaluate total shoot growth within the tree. Watersprout number and total length tended to be higher under severe dormant pruning and in fruited trees than under light dormant pruning and in defruited trees. This stimulation of watersprout length appeared to compensate for the concomitant lower total length of young shoots, resulting in a constant overall vegetative growth rate for the whole tree. In the second year of the experiment, watersprouts were either removed by summer pruning or not in order to evaluate watersprout incidence on the rest of the tree. After light and severe watersprout removal (WSR), the annual diametrical growth of FBS tended to be higher and lower, respectively, compared to trees not submitted to summer pruning. Light WSR might favour light interception in the centre of the canopy, thus improving assimilate production and allocation to FBS, whereas severe WSR could prevent carbohydrate export from watersprouts to FBS. Under our conditions, the limit at which WSR intensity became detrimental for FBS diametrical growth appeared to be after approximately 75% of the watersprouts were removed. Severe WSR appeared likely to improve fruit diameter, whereas it had no significant impact on the percentage of soluble solids.

The response of the frugivorous lion‐tailed macaque (Macaca silenus) to a period of fruit scarcity

Tropical rainforests show seasonal fluctuations in the abundance of fruits resulting in periods of resource scarcity for frugivores. We examined the response of an obligate frugivore, the lion-tailed macaque (LTM) (Macaca silenus), to a period of fruit scarcity in a rainforest in the Western Ghats, India. We estimated the abundance and distribution of fruit resources from food tree densities obtained from 348 point centered quadrats, and fruit availability from phenological monitoring of 195 trees of 15 reported major food species. Macronutrient content was estimated for fruits of 15 major food species. We estimated time spent feeding on different food items from 1,853 individual scans spanning 120 hr of observation of one habituated study group. There was a distinct period of fruit scarcity during the drier months of February to mid-March (Period 1) compared with late March and April (Period 2), separated by summer showers. Fruits available in Period 1 had lower soluble carbohydrate and lipid content and overall caloric value compared with Period 2. During the lean period, the LTM fed more on fruits of Drypetes wightii, which had the highest carbohydrate content, than on nectar of Palaquium ellipticum or Ficus spp., which had low carbohydrate content. During this period, the resource availability in a location significantly influenced the occurrence of feeding there. In Period 2, the group fed most on the seeds of Cullenia exarillata, the most abundant tree in the home-range and with the highest content of soluble carbohydrates. During this period, the abundance of food trees in fruit in a location did not seem to influence the occurrence of feeding. Low abundance, stochastic fruiting and, low quality might make Ficus spp. a poor fallback option for the LTM.

Food intake rates, assimilation efficiency, and transit times of Knysna (Tauraco corythaix) Turacos fed South African indigenous fruit

Fleshy-fruited plants and frugivores share a mutualistic relationship with plants offering the frugivores a reward of fleshy fruit pulp in order to disperse their seeds. However, all fruits are not equal in terms of energy available to frugivores. Consequently, we measured the assimilation efficiencies of fruits of six indigenous tree species for an avian frugivore, the Knysna Turaco (Tauraco corythaix). We predicted that the Turacos would process these indigenous fruits efficiently and have fast transit rates and high intake rates irrespective of species. Fruits were fed to the Turacos in separate trials to determine daily food and energy intake, assimilation efficiencies and digestive transit times. Digestive transit times of Knysna Turacos (c. 12–28 min) fall within the range of published examples for other frugivorous birds. Apparent assimilation efficiencies of the fruit ranged from c. 15–84% and were generally lower than those observed for other avian frugivores. Intake rates (in terms of wet weight) varied among the fruit species, and Knysna Turacos had greater intake rates on fruit which they are able to assimilate efficiently. Future studies looking at the nutritional composition of indigenous forest fruit may provide insight into the Knysna Turacos assimilation efficiency and consequently their food preferences and role as potential seed dispersers of fruiting tree species.

Enriching agroecosystems with fruit-producing tree species favors the abundance and richness of frugivorous and nectarivorous bats in Veracruz, Mexico

We evaluated how the abundance and richness of frugivorous and nectarivorous bat species differs among three types of common agroecosystems (diversified coffee plantations, simple coffee plantations and pastures) in Veracruz, Mexico, that represent a gradient of structural and floristic complexity. Using mixed effects models we demonstrated that both the richness and the total abundance of bats was higher in the diversified coffee plantations. We detected similar patterns on comparing the abundance of the four most abundant bat species. Neither season nor the season-agroecosystem interaction had any effect on the comparisons made. Using multiple regressions we found that the richness of plants that are useful to both people and bats had the most explanatory power for the richness and total abundance of frugivorous and nectarivorous bats, as well as for the abundance of Carollia sowelli, Glossophaga soricina and Sturnira spp. Our results indicate that agroecosystems value for conservation of fruit and nectar-eating bats increases as the fruit-bearing trees increases. For the effective conservation of these guilds of bats in tropical agroecosystems, a strategy of diversification with fruit-bearing species is highly recommended; such a strategy would benefit both agricultural producers and wildlife.

Toward Fungicidal Management of Laurel Wilt of Avocado.

Laurel wilt threatens commercial and residential production of avocado (Persea americana) in Florida. Laurel wilt on redbay (P. borbonia) was controlled previously with macroinfusions (injections) of Alamo, an injectable formulation of propiconazole. To determine whether Alamo macroinfusion would be cost effective in commercial avocado production, economic analyses were conducted for various macroinfusion scenarios and a standardized production situation in southern Florida. Under prevailing conditions, macroinfusion was not cost effective. In the interest of identifying alternative means to manage the disease, other fungicides and application measures were evaluated. In all, 20 fungicides in 15 chemical groups and 10 fungicide groups were examined in vitro. In vitro inhibition of the radial growth of the pathogen Raffaelea lauricola was determined on fungicide-amended malt extract agar; demethylation inhibitors (DMIs; fenarimol, myclobutanil, propiconazole, prothioconazole, triadimenol, triadimefon, and triticonazole), quinone outside inhibitors (azoxystrobin, pyraclostrobin, and fluoxastrobin), and a quinone inside inhibitor (fluazinam) had the greatest impact on radial growth (the concentration at which growth was reduced by 50% was ≥0.1 μg ml-1). In greenhouse studies, the most inhibitory products in vitro, plus thiabendazole and two products that were not tested in vitro, flutriafol and a potassium salts mixture of phosphorus acid, were tested for disease suppression on artificially inoculated, potted 'Simmonds,' a susceptible avocado cultivar. In general, soil drench applications of the above DMIs and thiabendazole but not azoxystrobin, pyraclostrobin, fluazinam, or the phosphorus acid salt provided significant control of disease (P < 0.05). Topical branch or trunk applications of propiconazole, and triadimenol in 2% Pentrabark, a bark-penetrating surfactant, were also effective at lower rates than were used in drench applications. Comparable levels of disease suppression were achieved when propiconazole was applied at 11% of the rates that were used in soil drenches. Although topical fungicide applications in bark-penetrating surfactants would be a less expensive practice than macroinfusion, moving sufficient concentrations of propiconazole or other fungicides into host xylem will be difficult in trees that are larger than the potted plants that were tested in these trials. Ongoing work examines means by which this goal might be met on fruit-bearing trees in the field.

Defruiting effect of young Fuyu persimmon ( Diospyros kaki) on assimilate partitioning in-season and early growth the next season

Changes in the distribution of dry matter and nonstructural carbohydrates in various parts of young ‘Fuyu’ persimmon ( Diospyros kaki) were examined with 3- and 4-year-old trees with (fruited) and without fruits (defruited). The effect of such changes was then monitored with regard to the magnitude of new growth the following year. From June 15 to November 1, fruiting significantly decreased the rate of dry weight accumulation in perennial parts of the tree. Dry matter was partitioned the most to fruits (68–72%) and the least to the roots. Of the total dry weight, root accounted for 8–27% in fruited and 58–62% in defruited trees. During this period, soluble sugars were three times more in fruited than in defruited trees, but more than 95% of sugars were in the fruits. Starch content increased in defruited trees, more than 93% of which being distributed to the perennial parts. Compared with fruited trees, defruiting in the previous year increased new shoot growth and the number of fruits the following year, with a 20–58% greater increase in dry matter. During the new growth from April 10 to June 10 the following year, root dry weight decreased by 30–32% in defruited trees, whereas it increased by 20–80% in the fruited ones. Soluble sugars in roots decreased by 8.8–19.7 g in defruited trees but increased by 9.7–12.3 g in fruited ones. Starch in roots decreased by 68–75.1 g in defruited trees but increased by 10.2–13.3 g in fruited ones. However, there were no significant differences in soluble sugars and starch in the newly grown parts. It was estimated that a 1-g difference in dry matter accumulated in the previous season resulted in a 116-mg and 256-mg difference in dry weight of newly grown parts, and a 6.5-mm and 17.5-mm new shoot in the following season for 3- and 4-year-old trees, respectively.

The use of fruiting synchrony by foraging mangabey monkeys: a ‘simple tool’ to find fruit

Previous research has shown that a considerable number of primates can remember the location and fruiting state of individual trees in their home range. This enables them to relocate fruit or predict whether previously encountered fruit has ripened. Recent studies, however, suggest that the ability of primates to cognitively map fruit-bearing trees is limited. In this study, we investigated an alternative and arguably simpler, more efficient strategy, the use of synchrony, a botanical characteristic of a large number of fruit species. Synchronous fruiting would allow the prediction of the fruiting state of a large number of trees without having to first check the trees. We studied whether rainforest primates, grey-cheeked mangabeys in the Kibale National Park, Uganda, used synchrony in fruit emergence to find fruit. We analysed the movements of adult males towards Uvariopsis congensis food trees, a strongly synchronous fruiting species with different local patterns of synchrony. Monkeys approached within crown distance, entered and inspected significantly more Uvariopsis trees when the percentage of trees with ripe fruit was high compared to when it was low. Since the effect was also found for empty trees, the monkeys likely followed a synchrony-based inspection strategy. We found no indication that the monkeys generalised this strategy to all Uvariopsis trees within their home range. Instead, they attended to fruiting peaks in local areas within the home range and adjusted their inspective behaviour accordingly revealing that non-human primates use botanical knowledge in a flexible way.

A new xerinae (Rodentia, Sciuridae) from the late Miocene of Toros-Menalla (Chad)

ABSTRACT Toumaï (Sahelanthropus tchadensis) is, to date, the oldest known hominine. Approximately 7 million years ago, it lived close to the northern shoreline of the paleo Lake Chad, which extended at that time 500 km north of its present location. Here, we describe a new xerine squirrel, Sabara oralacus, gen. et sp. nov., discovered near the site where Toumaï was unearthed. Study of associated fauna is essential to evaluate correctly the precise paleoenvironmental affinities of the first African hominines. The new squirrel displays a mosaic of dental and skull characters characterizing either the tribe Xerini or Protoxerini, which makes its taxonomic assignment at the tribe level difficult. From craniodental characters, we hypothesize that S. oralacus was a ground-dweller, digging burrows, probably with an ecological preference for forest to savannah environments associated with hard fruit-bearing trees.

Knysna Turacos ( Tauraco corythaix) do not improve seed germination of ingested fruit of some indigenous South African tree species

Seed dispersal plays an important role in the persistence, regeneration and maintenance of plant communities. It is therefore not surprising that much attention has been paid to the germination potential of seeds ingested by frugivorous animals. Consequently the aim of this study was to determine what effect ingestion of seeds by Knysna Turacos ( Tauraco corythaix) has on the germination rate and germination percentage of indigenous South African tree species. Fruits from twelve tree species were fed to the Turacos in separate trials and seed retention times were determined as it has been suggested that a longer seed retention time may increase germination rates. At the end of each trial, seeds were extracted from excreta of individual birds and planted in trays containing potting soil. Germination was recorded daily until 14 days of no germination. Knysna Turacos seed retention times were in the range of those obtained by other studies, with Ficus sur seeds having the fastest retention times (12.4 ± 0.8 min) and Celtis africana the slowest (34.6 ± 5.6 min). Seed ingestion by Knysna Turacos did not influence the rate at which seeds germinated in 83% of the tree species, but ingested Ficus lutea and Ficus natalensis seeds germinated significantly sooner than whole fruit seeds. Future studies relating the composition of indigenous forest fruits to food preferences of Knysna Turacos may give insight into their role as potential seed dispersers of indigenous fruiting tree species.

Viabilidade "in vitro" de grãos de pólen de bacurizeiro - Clusiaceae

O bacurizeiro (Platonia insignis Mart.) é uma frutífera nativa da Amazônia, que apresenta alogamia acentuada e autoincompatibilidade esporofítica. A viabilidade in vitro tem sido utilizada para representar a capacidade potencial do pólen em completar o processo de fertilização O objetivo do presente trabalho foi estudar a viabilidade de polens de bacurizeiro por meio da germinação in vitro , por ser esta uma técnica em que o comportamento germinativo é semelhante in vivo . Os ensaios foram conduzidos em laboratório, em um delineamento inteiramente casualizado, analisados em esquema fatorial 2 x 3 x 4, em que: 2=formas de propagação (pé-franco e enxertada); 3=estágios da antese (pré-antese, antese e pós-antese), e 4=concentrações de sacarose (0; 7,5; 10 e 20%), com 10 repetições. Houve diferença significativa na germinação do pólen, sendo que, via polinização manual, o pólen deve ser coletado na antese, enquanto o melhor meio para a germinação in vitro é com 7,5 g de sacarose.

Brazil cherry (Eugenia dombeyi) – an underutilized fruit species of the American tropics

Introduction . Brazil cherry or grumichama is a little-known, underutilized fruit species of the Myrtaceae family; this tree forms part of CATIE’s field collection of tropical fruits. It is native to southern Brazil and cultivated on a small scale in Brazil, Paraguay, Florida and Hawaii. Materials and methods . Fruit traits were assessed among 12 seedling trees of the same source of origin, and the potential of fresh fruit and derived products was surveyed among employees and students. Results and discussion . Fruit traits (total soluble solids, fruit weight, fruit diameter, flesh weight, seed weight and number of seeds per fruit) differed significantly among the 12 trees. Survey respondents rated derived products such as yellow jam, (red grumichama + citrus) jam and (red grumichama + mocha) jam higher than fresh fruit, red jam, grumichama wine and juice. Conclusion . Grown in home gardens as an ornamental or as a fruit-bearing tree, or planted as a living fence or windbreak, this fruit crop merits a place in tropical and subtropical settings due to the attractiveness of the tree, its foliage and bloom, its tasty fruit, its contribution to agricultural biodiversity, and the possibility of generating value-added products at the farm, household or community level. For fruit production, vegetative propagation is recommended to retain high quality traits

Relationship between reproductive behavior and new shoot development in 5-year-old branches of olive trees (Olea europaea L.)

The development of new shoots plays a central role in the complex interactions determining vegetative and reproductive growth in woody plants. To explore this role we evaluated the new shoots in the olive tree, Olea euro- paea L., and the effect of fruiting on new shoot growth and subsequent flowering. Five-year-old branches served as canopy subunits in order to obtain a global, whole-tree view of new shoot number, size and morphological origin. The non-bearing trees had many more shoots than the fruit- bearing trees, and a greater number of longer shoots. In both bearing conditions, however, the majority of shoots were less than 4 cm long, with shoots of progressively longer lengths present in successively decreasing frequen- cies. Six major shoot types were defined on the basis of apical or lateral bud origin and of parent shoot age. On fruit-bearing trees, the new shoots originated predomi- nantly from the shoot apex, while on non-fruiting trees, they formed mainly from axillary buds, but in both cases, they tended to develop on younger parent shoots. The previous bearing condition of the tree was the main determinant for subsequent inflorescence development, which was independent of both shoot type and length. Thus, reproductive behavior strongly affected both the amount and type of new branching, but subsequent flowering level was more influenced by previous bearing than by the potential flowering sites on new shoots.

Биологические особенности применения омолаживающей обрезки в плодоносящих садах яблони

В статье дана сравнительная оценка разных видов обрезки в плодоносящих садах яблони. Установлено влияние омолаживающей обрезки на суммарную длину прироста и урожайность деревьев. Показано сочетание механизированного ограничения высоты деревьев с последующей обработкой восстановительных побегов ретардантами.

Digestive efficiency of Knysna and purple-crested turacos fed varying concentrations of equicaloric and equimolar artificial fruit

Avian frugivores have been somewhat poorly studied with regards to the effects that different fruit sugar types and concentrations have on their digestive efficiencies. Therefore, two relatively large South African frugivores, the Knysna turaco (Tauraco corythaix) and the purple-crested turaco (Gallirex porphyreolophus), were fed artificial fruit that contained equicaloric and equimolar concentrations of different sugars, to determine their daily food and energy intake, digestive efficiencies and digestive transit times. The artificial fruit contained 6.6, 12.4 or 22%, or 0.42, 0.83 or 1.66 mol l(-1) sucrose or glucose. Food intake of both turaco species increased with decreasing sugar concentration and molarity, irrespective of sugar type, suggesting compensatory mechanisms for energy requirements. Apparent assimilation efficiencies of both turaco species ranged from 61.4-90.0% and 60.2-92.4% for equicaloric and equimolar artificial fruit diets, respectively. Digestive transit times for both turaco species were slowed with an increase in sugar concentration and molarity, irrespective of sugar type. Consequently these two frugivores appear to be tolerant of sugar type and would be expected to select fruits based on energy yields. Future studies of the composition of indigenous forest fruit sugars may give insight into food preferences of the turaco species and their role as potential seed dispersers of fruiting tree species.