Trench layering using indole-3-butyric acid and local organic substrate mixtures to enhance rooting and survival of apple rootstocks

Apples ( Malus domestica ) were introduced to enhance nutrition and improve livelihoods of famers in highlands of Uganda. However, adoption and commercialisation of apples is largely constrained by low quality rootstocks due to poor rooting and low survivability. This study determined the effect of organic substrate mixtures (OSM) and indole-3-butyric acid (IBA) on rooting, sprouting and survival characteristics of apple rootstocks propagated by trench layering. Four apple rootstock varieties (M106, M109, MM793 and bitten-felder) were planted in OSM (Site soil as control, TsaOm and TsdOm) then treated with IBA concentrations (IBA-0 ppm, IBA-4000 ppm and IBA-8000 ppm) in a factorial randomised block design with three replications. Results showed significant (P<0.001) variability among rootstocks for all characters. OSM significantly (P<0.01) increased rooting, root numbers and root length while IBA significantly (P<0.01) increased all traits, except rooting. The highest rooting (46.7%), root numbers (23.1) and root length (14.9cm), and sprout length (59.5cm) were obtained in bitten felder under TsaOm + IBA-4000ppm, TsaOm, and TsdOm, respectively. For M106, maximum rooting (28.1%) and root numbers (22.3) were obtained under TsaOm + IBA-8000ppm while root (14.3cm) and sprout (35.2cm) lengths under TsdOm. TsaOm gave the highest root numbers (14.2), root (12.8cm) and sprout (30.7cm) lengths in M109 likewise root (7.8cm) and sprout (38.3cm) lengths in MM793. Logistic regression revealed that rooting, sprout length, and IBA-4000ppm significantly (P<0.01) increased survival of apple rootstocks. The highest survival rates in bitten felder and M106 were 52.4% and 51.7% under TsdOm + IBA-4000 ppm and TsdOm + IBA-8000 ppm respectively; likewise 49.5% in M109 and 51.7% in MM793 both treated with IBA-8000 ppm. The results demonstrate that trench layering with OSM and IBA improves rooting and survival of apple rootstocks which might improve farmers\u2019 access to quality apple planting material.Les pommes ( Malus domestica ) \ue9taient introduites pour renforcer la nutrition et am\ue9liorer le niveau de vie des producteurs dans les r\ue9gions montagneuses d\u2019Ouganda. Toutefois, l\u2019adoption et la commercialisation des pommes sont largement limit\ue9es par la faible qualit\ue9 des porte-greffes \ue0 cause du pauvre enracinement et la faible capacit\ue9 de survie. Cette \ue9tude visait \ue0 d\ue9terminer l\u2019effet des m\ue9langes du substrat organique (OSM) et l\u2019acide indole-3-butyrique (IBA) sur l\u2019enracinement, la germination et les caract\ue9ristiques de survie des porte-greffes de la pomme propag\ue9e par le marcottage de tranch\ue9e. Quatre portes greffes des vari\ue9t\ue9s de pomme (M106, M109, MM793 et bitten-felder) \ue9taient plant\ue9es dans l\u2019OSM (site de sol servant de contr\uf4le, TsaOm et TSdOm) et trait\ue9e avec diff\ue9rentes concentrations de l\u2019IBA (IBA-0 ppm, IBA-4000 ppm et IBA-8000 ppm) dans un design factoriel \ue0 blocks compl\ue8tement al\ue9atoires avec trois r\ue9plications. Les r\ue9sultats ont montr\ue9 de variabilit\ue9 significative (P<0,001) entre les porte-greffes des vari\ue9t\ue9s pour tous les caract\ue8res. OSM significativement (P<0.01) a fait accro\ueetre l\u2019enracinement, le nombre de racines et la longueur de la racine; alors que IBA a augment\ue9 significativement (P<0.001) tous les traits, sauf l\u2019enracinement. Les plus grandes valeurs des caract\ue8res \ue0 savoir\ua0; l\u2019enracinement (46,7%), le nombre de racines (23,1), la longueur des racines (14,9 cm), et la longueur des pousses (59,5cm) \ue9taient obtenues sur bitten felder sous TsaOm + IBA-4000ppm, TsaOm, et TsdOm, respectivement. Pour M106, les valeurs maximales de l\u2019enracinement (28,1%) et de nombre de racines (22.3) \ue9taient obtenues sous TsaOm + IBA-8000ppm alors que les valeurs maximales de la longueur des racines (14,3 cm) et des pousses (35,2 cm) sous TsdOM. TsaOm ont donn\ue9 le plus grand nombre de racines (14,2), la plus grande longueur des racines (12,8 cm) et de pousses (30,7 cm) dans M109 pareillement \ue0 la longueur des racines (7,8 cm) et de pousses (38,3 cm) dans MM793. La r\ue9gression logistique a r\ue9v\ue9l\ue9 que l\u2019enracinement, la longueur de la pousse et IBA-400ppm ont augment\ue9 significativement (P<0,01) la survie des porte-greffes de la pomme. Les plus forts taux de survies sur le bitten felder et M106 \ue9taient 52,4% et 51,7% sous TsdOm+IBA-4000 ppm et TsdOm+IBA-8000 ppm, respectivement\ua0; de m\ueame 49,5% ont \ue9t\ue9 obtenus sur M109 et 51,7% sur MM793 tous trait\ue9s avec IBA-8000 ppm. Les r\ue9sultats ont d\ue9montr\ue9 que le marcottage de tranch\ue9e avec OSM et IBA am\ue9liore l\u2019racinement et la survie des porte-greffes qui pourrait am\ue9liorer l\u2019acc\ue8s des producteurs \ue0 des mat\ue9riels de plantation de pomme de qualit\ue9

Discovery of novel herpes simplexviruses in wild gorillas, bonobos, and chimpanzees supports zoonotic origin of HSV-2

Viruses closely related to human pathogens can reveal the origins of human infectious diseases. Human herpes simplexvirus type 1 (HSV-1) and type 2 (HSV-2) are hypothesized to have arisen via host-virus codivergence and cross-species transmission. We report the discovery of novel herpes simplexviruses during a large-scale screening of fecal samples from wild gorillas, bonobos, and chimpanzees. Phylogenetic analysis indicates that, contrary to expectation, simplexviruses from these African apes are all more closely related to HSV-2 than to HSV-1. Molecular clock-based hypothesis testing suggests the divergence between HSV-1 and the African great ape simplexviruses likely represents a codivergence event between humans and gorillas. The simplexviruses infecting African great apes subsequently experienced multiple cross-species transmission events over the past 3 My, the most recent of which occurred between humans and bonobos around 1 Ma. These findings revise our understanding of the origins of human herpes simplexviruses and suggest that HSV-2 is one of the earliest zoonotic pathogens

Discovery of Novel Herpes Simplexviruses in Wild Gorillas, Bonobos, and Chimpanzees Supports Zoonotic Origin of HSV-2

Viruses closely related to human pathogens can reveal the origins of human infectious diseases. Human herpes simplexvirus type 1 (HSV-1) and type 2 (HSV-2) are hypothesized to have arisen via host-virus codivergence and crossspecies transmission. We report the discovery of novel herpes simplexviruses during a large-scale screening of fecal samples from wild gorillas, bonobos, and chimpanzees. Phylogenetic analysis indicates that, contrary to expectation, simplexviruses from these African apes are all more closely related to HSV-2 than to HSV-1. Molecular clock-based hypothesis testing suggests the divergence between HSV-1 and the African great ape simplexviruses likely represents a codivergence event between humans and gorillas. The simplexviruses infecting African great apes subsequently experienced multiple cross-species transmission events over the past 3 My, the most recent of which occurred between humans and bonobos around 1 Ma. These findings revise our understanding of the origins of human herpes simplexviruses and suggest that HSV-2 is one of the earliest zoonotic pathogens

Seed Dispersal Anachronisms: Rethinking the Fruits Extinct Megafauna Ate

Background: Some neotropical, fleshy-fruited plants have fruits structurally similar to paleotropical fruits dispersed by megafauna (mammals.10 3 kg), yet these dispersers were extinct in South America 10–15 Kyr BP. Anachronic dispersal systems are best explained by interactions with extinct animals and show impaired dispersal resulting in altered seed dispersal dynamics. Methodology/Principal Findings: We introduce an operational definition of megafaunal fruits and perform a comparative analysis of 103 Neotropical fruit species fitting this dispersal mode. We define two megafaunal fruit types based on previous analyses of elephant fruits: fruits 4–10 cm in diameter with up to five large seeds, and fruits.10 cm diameter with numerous small seeds. Megafaunal fruits are well represented in unrelated families such as Sapotaceae, Fabaceae, Solanaceae, Apocynaceae, Malvaceae, Caryocaraceae, and Arecaceae and combine an overbuilt design (large fruit mass and size) with either a single or few (,3 seeds) extremely large seeds or many small seeds (usually.100 seeds). Within-family and within-genus contrasts between megafaunal and non-megafaunal groups of species indicate a marked difference in fruit diameter and fruit mass but less so for individual seed mass, with a significant trend for megafaunal fruits to have larger seeds and seediness. Conclusions/Significance: Megafaunal fruits allow plants to circumvent the trade-off between seed size and dispersal b

Averting biodiversity collapse in tropical forest protected areas

The rapid disruption of tropical forests probably imperils global biodiversity more than any other contemporary phenomenon¹⁻³. With deforestation advancing quickly, protected areas are increasingly becoming final refuges for threatened species and natural ecosystem processes. However, many protected areas in the tropics are themselves vulnerable to human encroachment and other environmental stresses⁴⁻⁹. As pressures mount, it is vital to know whether existing reserves can sustain their biodiversity. A critical constraint in addressing this question has been that data describing a broad array of biodiversity groups have been unavailable for a sufficiently large and representative sample of reserves. Here we present a uniquely comprehensive data set on changes over the past 20 to 30 years in 31 functional groups of species and 21 potential drivers of environmental change, for 60 protected areas stratified across the world’s major tropical regions. Our analysis reveals great variation in reserve ‘health’: about half of all reserves have been effective or performed passably, but the rest are experiencing an erosion of biodiversity that is often alarmingly widespread taxonomically and functionally. Habitat disruption, hunting and forest-product exploitation were the strongest predictors of declining reserve health. Crucially, environmental changes immediately outside reserves seemed nearly as important as those inside in determining their ecological fate, with changes inside reserves strongly mirroring those occurring around them. These findings suggest that tropical protected areas are often intimately linked ecologically to their surrounding habitats, and that a failure to stem broad-scale loss and degradation of such habitats could sharply increase the likelihood of serious biodiversity declines.Keywords: Ecology, Environmental scienc

Spatial patterns of tree recruitment in East African tropical forests that have lost their vertebrate seed dispersers

The direct removal of adult trees by logging affects tree recruitment in tropical rain forests. However, secondary effects of logging, such as loss of vertebrate seed dispersers may also affect tree recruitment. We studied the recruitment and spatial distribution of five tree species namely Balanites wilsoniana, Celtis zenkeri, Chrysophyllum albidum, Cordia millenii and Ricinodendron heudelotii in Kibale, Budongo and Mabira Forests in Uganda. These forests have been subjected to varying degrees of disturbance leading to changes in their vertebrate seed dispersers. Vertebrate frugivores of the five tree species were identified. Three 1-ha plots were established around adult trees of the same five species in each forest and the distance from the juveniles to the nearest adult conspecific was measured to generate a recruitment curve. Frugivore visitation rates were high in the less disturbed Budongo and Kibale (2.2 and 1.6 individuals h-1 respectively) compared with the highly disturbed Mabira (0.9 individuals h-1). In the frugivore-impoverished forest, 70-90% of juveniles established beneath adult conspecifics, whereas in the less-disturbed forests juveniles were established up to 80 m from adult conspecifics. Shade-tolerant species capable of recruiting beneath adult conspecifics appeared to maintain their populations without dispersal. Consequently, disturbances leading to significant loss of vertebrates may alter tree recruitment and spatial distribution with consequences for long-term population viability of shade-intolerant tropical trees. Copyright © 2010 Cambridge University Press

Balanites wilsoniana: Regeneration with and without elephants

Tropical forest trees that produce large fruits and/or large seeds are believed to be dependant on a few and often rare large vertebrates for dispersal. However, little is known about the population dynamics of such trees when they lose their specialised dispersers. This study examines the juvenile spatial distribution of Balanites wilsoniana, Dawe and Spraque, which is believed to be dependant solely on elephants for dispersal, in forests with and without elephants. Using camera traps, elephants were confirmed to be the only frugivores feeding and thus dispersing Balanites wilsoniana fruits. There was a high density of seedlings beneath adult trees in one forest without elephants, which was attributed to low seed and seedling predation in this forest. Nevertheless, it was only in the forest with elephants that juveniles were established away from adult trees. Analysis of the spatial distribution of these juveniles by size revealed that saplings and poles are more likely to be found away from adult trees thus providing evidence that dispersal enhances juvenile survival. This study underlines the importance of seed dispersal for trees that cannot maintain their populations through seedlings germinating and surviving beneath adult conspecifics. The study also demonstrates that loss of vertebrates has ramifications for tree species dynamics above and beyond loss of seed dispersers. © 2006 Elsevier Ltd. All rights reserved

Effect of gap size and age on climber abundance and diversity in Budongo Forest Reserve, Uganda

A study of the effects of gap size and age on climber abundance and diversity was carried out in Budongo Forest Reserve in Uganda. Data were collected from compartments N5, W21, B1 and B3. Stump records were used to locate and estimate the ages of 78 gaps. Sample plots 5 √ó 5 m were set up in the gaps to assess climber abundance and diversity. Climbers were more abundant and diverse in gaps that were more than 400 m2, 15 months old and had more than 25% canopy opening. Momordica foetida was the most abundant climber species occurring on stems, branches and crowns of seedlings and saplings. Therefore, in order to keep natural regeneration free from climber tangles and produce good quality timber, climber control should be a major activity in tropical high forest management