Variation of pomelo (Citrus grandis (L.) Osbeck) in Nepal and participatory selection of strains for further improvement

A farmers’ participatory survey was carried out in the mid-hill and plain (Terai) regions of Nepal to assess the diversity, consumers’ preference for fruit quality and potential for selection of elite pomelo clones. A wide variation of morphological characters of tree, fruit, leaf and seed was identified from information gathered and from laboratory analysis. Multivariate analysis of the data produced five discrete groups, which were represented by plants from different agro-ecological regions and soil types. The groups differed significantly in yield efficiency, fruit shape and size, pulp, juice, total soluble solids and acid content, seed number, leaf shape and size. Some fruit characters, such as yield, size and acid content were found to be affected by environment and genotype, whereas others, such as fruit shape, pulp colour, seed number, bitterness were not affected by environment. Leaf shape and petiole wing shape were also not affected by the environment. Farmers were more interested in quality characteristics rather than to aspects of yield. Six superior types were identified.     

Bringing Agroforestry Technology to Farmers in the Philippines: Identifying Constraints to the Success of Extension Activities Using Systems Modelling

This paper presents a systems modelling approach to evaluating the success of an agroforestry extension program in Leyte, the Philippines. During the program, variables which are intrinsic to farmers’ socio-economic and farming systems were found to have influenced the uptake and acceptance of extension advice. Evaluation of the program therefore depended on identifying the variables and their interdependencies and assessing their relative influence on program outputs. For this purpose, a systems approach which encourages breaking systems into component variables, but also acknowledges the context of problems, assisted construction of models. Using both empirical data collected during program activities and input from stakeholders, Bayesian Belief Network software was used to predict critical success factors for four aspects of the overall extension system, namely recruitment, use of written extension materials, farmers’ self-efficacy and retention of participating farmers throughout the program. A key predicted constraint to program recruitment is farmers’ perception of harvest security and while this variable can be partly addressed through dissemination of information on harvesting legislation, title security cannot. Differing levels of farmers’ education result in differences in predicted reading ability, comprehension of extension literature and possible misconstrual of information. The variable most critical to the development of farmers’ self-efficacy is extended on-farm technical assistance and support.     

Agroecological variation in the fruits and nuts of shea butter tree (<Emphasis Type="Italic">Vitellaria paradoxa</Emphasis> C. F. Gaertn.) in Nigeria

A basic understanding of the relationships between key phenotypic characters of the shea butter tree is considered a crucial step to its genetic improvement. As such fruit samples of the shea butter tree, Vitellaria paradoxa, were collected from nine locations in July, 2006, to determine the fruit and nut characteristics of the species. The choice of the locations was informed by the need to have as broad a picture of the trait diversity as possible. The nine locations covered were Akwanga, Ilorin, Lokoja, Makurdi, Minna (in the Southern Guinea Savanna), Jalingo, Kachia (in the Northern Guinea Savanna), Kano and Yola (in the Sudan Savanna), recognized as the main shea butter tree belt in Nigeria. Analysis of variance indicated significant (P < 0.05) variations in fruit and nut traits across agro-ecologies and specific locations (representing individual accessions). The Northern Guinea Savanna accessions had higher values for nut weight, nut length kernel weight and fruit weight. The Southern Guinea Savanna fruits were, however, superior in percent pulp weight. Nuts sourced from Akwanga were comparatively heavier and longer, had wider diameters, heavier kernels and higher percent testa weights which did not differ from those of Minna. Also fruits from Akwanga had significantly (P < 0.05) higher values for fruit length, fruit diameter, fruit weight and pulp weight. The Lokoja accession was superior to the rest in percent pulp weight, but it recorded least nut weight and nut length values. Nut shape index varied from 2.3 (Makurdi) to 1.5 (Jalingo). Nuts from Akwanga, Jalingo and Kachia had wide variation in nut weight in contrast to those from Lokoja, Makurdi and Yola (that were relatively similar). Fruit length had significantly (P < 0.05) positive relationship with pulp weight, fruit weight and fruit diameter. Nut diameter, however, had a negative relationship with percent pulp weight. A strong influence of some environmental variables on certain phenotypic traits was detected. Principal components analysis indicated nut weight, nut shape index, percent pulp weight and fruit shape index as the key discriminant variables for grouping shea butter fruit and nut in Nigeria. Results of this study indicated considerable diversity in fruit and nut traits of the shea butter tree in Nigeria, suggesting the possibility of selection for desirable traits.     

Farmers preferences,uncertainties and opportunities in fruit-tree cultivation in Northeast Luzon

The world production of tropical fruit was estimated at about 65 Mt in 2002, of which developing countries accounted for 98%. Although most commercial fruit tree crops are cultivated by large-scale commercial enterprises, smallholder fruit-tree cultivation receives much attention in projects aimed at rural development, conservation farming and agroforestry in developing countries. In the Philippines, the integration of fruit trees in smallholder upland farming systems has been promoted since the 1970s. The aim of this paper is to investigate farmers’ views on small-scale fruit-tree cultivation based on fieldwork conducted in three upland villages of Northeast Luzon. The factors influencing farmers’ preferences are explored and the costs and benefits of fruit tree cultivation compared with those for seasonal cash crops over a 10-year period. Markets for fruit-tree products are identified, at both local and supra-local levels, and risks, uncertainties and opportunities associated with fruit-tree cultivation are discussed. Despite extensive promotion, the adoption of fruit trees in farming systems has occurred at a relatively low pace. In contrast, the cultivation of seasonal cash crops, particularly high-yielding rice and corn varieties, spread rapidly in the 1970s and 1980s. These crops are planted in monocultures with high inputs of fertilizers and pesticides. Farmers consider fruit trees as a subordinate crop much less profitable than seasonal cash crops, which is in stark contrast with the results of economic analyses of a 10-year production cycle. The Net Present Value (NPV) for citrus (Citrus reticulate) cultivation is at least two times the NPV for irrigated rice and as much as four times the NPV for corn, even at discount rates up to 20%. Farmers’ knowledge of tree management and species selection proved to be inadequate, contributing indirectly to low growth rates and fruit production. Marketing opportunities are not fully utilised as evident from unstable network channels for fruit-tree sales, lack of expertise in fruit-tree marketing and insufficient knowledge on market demands, quality production and market location.     

Jatropha adoption: a statistical observational study of factors influencing Malian farmers’ decision to grow Jatropha

An accurate understanding of the factors that influence farmers’ adoption of a crop is critical for effective policy promotion and technical support. Agroforestry crop adoption is a complex topic involving many factors not often addressed by tradition crop adoption models. This complexity, when applied to Jatropha (Jatropha curcas L.), an often widely promoted yet poorly understood biofuel feedstock crop, requires a detailed analysis across diverse topics. Such an analysis was carried out through applying rigorous statistical tools to the data acquired from an interview-based household survey among Malian farmers and was combined with relevant geospatial datasets. The results showed that though farmers’ adoption is based on a wide variety of factors from household preferences, resource endowments, bio-physical factors, and market incentives, factors related to risk and uncertainty appear to provide the strongest correlation. Specifically, the number of visits that an agriculture extension agent makes with a farmer was found to be the most significant factor influencing adoption.     

Farmers’ perceptions of tree mortality, pests and pest management practices in agroforestry in Malawi, Mozambique and Zambia

Pest management research within the context of agroforestry is in its infancy, and it is often difficult to say when a particular pest justifies investment in research to establish facts. Understanding the potentials and drawbacks of farmers’ indigenous ecological knowledge (ethnoecology) may form the basis for constructive collaboration between farmers, agroforestry scientists and extension staff. Therefore, the objectives of the study were to (1) assess farmers’ knowledge and perceptions of pests, (2) prioritize pest problems that limit tree planting and maize production based on farmers’ own criteria and (3) to identify farmers’ indigenous pest management practices for priority pests. Data were collected using community meetings, individual interviews and direct observation by the first author. The farmers involved in this study in eastern Zambia had over ten years of experience, while most of the farmers in Mozambique and parts of southern Malawi were new to agroforestry. Farmers perceived insects as the major causes of tree mortality, followed by drought, bush fires and browsing by livestock. Among the biological constraints to maize production, insects (particularly termites and stalk bores) and weeds (particularly Striga asiatica) were more important in farmers’ minds than crop diseases. Fundamentally, the farmers’ perception of the causes of tree mortality and crop pests agreed with researchers’ perceptions and the literature. Both termite and witch weed problems were associated with low soil quality, and farmers use various indigenous control practices to control these pests. Some farmers did not know the causes of tree mortality, and hence do not take action. Farmer’s perception of tree mortality was found to be a function of operator-specific variables such as sex, level of education and years of experience with tree species.     

The Influence of Farmers�� Mental Models on an Agroforestry Extension Program in the Philippines

The influence of farmers’ mental models on the success of an agroforestry extension program on Leyte Island in the Philippines was investigated. Knowledge of farmers’ mental models and hence the likely acceptance of technology was used to inform the design of a hypothetically expanded program. To gain an insight into the reasons behind differing acceptance of extension assistance, data were collected and analysed from formal interviews, translated conversations and visual observations. The data provided a chain of evidence and triangulation between farmers’ stated intentions and their actions. Farmers had little prior knowledge of nursery technology and were highly receptive to extension assistance which enabled them to develop high self-efficacy in seedling production. However, farmers’ rejection of silvicultural advice to thin and prune existing plantations was predicated by existing attitudes to forest resource management. Farmers also expressed a strong preference for a low-cost and low-input approach to establishing timber trees. Visual observations of farmers’ tree establishment practices indicated the existence of gaps in their knowledge of tree growth processes. This investigation illustrates the need to elicit farmers’ mental models as a parallel enquiry to extension activities. If agroforestry extension is to be constructivist and participatory, accommodation of farmers’ mental models and modification of program goals may be necessary. Relatively little is known about the reasons for farmers’ acceptance or rejection of silviculture in Leyte and these results indicate that further research into the way that farmers’ mental models filter and guide acceptance of advice may be worthwhile.     

Household decision-making in agroforestry parklands of Sudano-Sahelian Mali

This study examines farmers’ knowledge and management of soil fertility and vegetation in Vitellaria paradoxa and Cordyla pinnata dominated agroforestry parklands in a Sudano-Sahelian region of Mali. Qualitative data from a series of semi-structured interviews were used to construct an empirically based typology of farmer practices. These interrelated practices center on famers’ agroecological knowledge, decision-making, and cropping strategies and are conceptualized as variable and adjustable socioecological responses to environmental and socioeconomic contingencies. The typology categorizes farmers in terms of their capacity for managing parkland soil and tree resources in an ecologically sustainable manner while negotiating livelihood challenges. It identifies the ideal farmer as one who practices the following: (1) use of environmental knowledge that considers multidimensional relationships among ecological and social components of parkland systems, (2) agricultural techniques that adaptively combine aspects of intensive and traditional extensive agriculture, and (3) natural resource decision-making that explicitly includes women’s environmental knowledge and livelihood strategies.     

Agroforestry adoption and maintenance: self-efficacy, attitudes and socio-economic factors

Agroforestry is a key land use in the development of ecological corridors in tropical rainforests biomes. This research tested the social dimensions of agroforestry adoption and maintenance in the Atlantic rainforest of Southern Bahia, Brazil. A quasi-experiment research design compared a group of farmers who participated in an agroforestry development program with a group of similar farmers who were not participants in the program. The effects of the program on the participants’ self-efficacy, attitudes and intentions to adopt or maintain agroforestry were tested. The effects of socio-economic factors and attitudes were also compared to self-efficacy in terms of farmers’ intentions to adopt or maintain agroforestry. Results indicate that the program neither raised nor lowered the farmers’ attitudes, self-efficacy or intentions to adopt or maintain agroforestry. However, multiple regression and logistic model analyses indicate that perceived behavioral control, attitudes about conservation and available labor contributed most significantly to farmers’ intentions to adopt or maintain agroforestry. Overall, perceived behavioral control proved to have the most significant correlation with farmers’ intentions to adopt or maintain agroforestry. Therefore, agroforestry development programs could benefit from focusing on farmers’ perceived control of certain behaviors to enhance the persistence of agroforestry practices.     

Factors affecting the adoption of agroforestry practices by farmers in Cameroon

This paper presents empirical evidence on the impact of socio-economic factors on the adoption of agroforestry practices in Cameroon. The analysis uses primary farm-level data collected from June to December 1996. Three major provinces of the country were covered, namely Centre, Southwest and Northwest Several agroforestry technologies have been promoted among farmers in the zone, including alley farming, improved fallow, live fencing, cut-and-carry fodder and apiculture. The status of adoption of each agroforestry practice is described and factors that affect adoption identified. These are gender of farmer, household family size, level of education, farmer’s experience, membership within farmers’ associations, contact with research and extension, security of land tenure, agroecological zone, distance of the village from nearest town, village accessibility and income from livestock. Research findings indicate that since factors affecting farmers’ adoption of agroforestry practices differ across techniques, generalisation is to be avoided.     

Morphological parameters and genetic diversity of progenies from seed production areas and unimproved stands of teak (Tectona grandis L.f.) in India

We compared morphological and genetic attributes of prog-eny obtained from three seed production areas (SPAs) and three corre-sponding unimproved stands (UIS) of teak (Tectona grandis L.f) at three bro...     

Variability in seed- and seedling-related traits of <Emphasis Type="Italic">Millettia ferruginea</Emphasis>, a potential agroforestry species

Millettia ferruginea (Hochst.) Baker is a potential agroforestry species endemic to Ethiopia. No documented information exists about genetic variation in this species, thus baseline information is needed to initiate improvement program. Here, we quantified variations in seed size, germination and seedling growth at nursery stage based on seeds collected from six sites across the natural range of distribution of the species in Ethiopia. All seed- and seedling-related traits exhibited highly significant differences among seed sources (P < 0.01), and the magnitude of genetic variation was substantially higher (77–99%) than the environmental variation. The genetic advance as percent of the mean was higher for germination capacity (69.4%) and seed weight (31.7%) than for other traits, suggesting that the population means for these traits may be changed considerably by selecting the superior 5% of the genotypes. There were strong phenotypic (r_p = 0.81) and genotypic (r_g = 0.89) correlations between seed width and seed weight, so also between seedling height and root collar diameter (r_p = 0.95 and r_g = 1.00). In conclusion, the results reveal the existence of substantial genetic variation, which can be utilized to initiate tree improvement program of the species and for gene conservation in seed banks. In memory of the late Abraham Loha, who passed away during the writing process.     

Genetic diversity of Lithocarpus harlandii populations in three forest communities with different succession stages

By using random amplified polymorphic DNA (RAPD) technique, this paper studied the genetic diversity and genetic differentiation of Lithocarpus harlandii populations in three forest communities (coniferous forest, coniferous and broad-leaved mixed forest, and evergreen broad-leaved forest) with different succession stages in Tiantai Mountain in Zhejiang Province. The results showed that a total of 173 repetitive loci were produced in 60 individuals of L. harlandii by 12 random primers, among which, 152 loci were polymorphic, and the total percentage of polymorphic loci was 87.86%. The average percentage of polymorphic loci of the populations was 65.32%, and their total genetic diversity estimated by Shannon information index was 0.4529, with an average of 0.3458, while that judged from Nei’s index was 0.3004, with an average of 0.2320. The percentage of polymorphic loci, Shannon information index, and Nei’s index of the populations were in the sequence of coniferous forest community > coniferous and broad-leaved mixed forest community > evergreen broad-leaved forest community. Analysis of molecular variance (AMOVA) showed that 72.85% of genetic variance was found within the populations, and 27.15% of genetic variance resided among the populations. The coefficient of gene diferentiation was 0.2277, and the gene flow was 1.6949. The genetic structure of L. harlandii was influenced not only by the biological characteristics of this species, but also by the microenvironment of different communities. The mean of genetic identity among three populations of L. harlandii was 0.8662, and the mean of their genetic distance was 0.1442. The genetic similarity between coniferous and broad-leaved mixed forest community and evergreen broad-leaved forest community was the highest, while that between evergreen broad-leaved forest community and coniferous forest community was the lowest. The unweighted pair group method with arithmeticmean (UPGMA) cluster analysis based on Nei’s genetic distance showed that conierous and broad-leaved mixed forest community first gathered with evergreen broad-leaved forest community, and then with coniferous forest community. __________ Translated from Chinese Journal of Ecology, 2007, 26(4): 509–514 [译自: 生态学杂志]     

江西省油茶农家品种表型多样性研究

江西省油茶农家品种栽培历史悠久,遗传资源丰富。调查并分析江西省油茶农家品种表型性状多样性,结果表明:不同农家种质果实、花和叶片都存在较大差异,各性状变异系数在0.07~0.50之间,遗传多样性指数在1.516~2.137之间,表明江西省油茶农家种质具有丰富的遗传信息和选择潜力。数量性状相关性分析表明,叶宽、花冠直径、单果重3个指标与其他指标关联性强。主成分分析表明,单果重、果高、果径、果皮厚4个数量性状具有丰富的遗传信息,可作为果实优先评价项目,而叶长、叶宽、叶周长、叶面积4个数量性状可作为叶片优先评价项目。     

Wild fruit resources and exploitation in Xiaoxing’an Mountains

The ornamental characters, nutritious composition, edible value and medical value of thirteen kinds of major wild fruit resources in Xiaoxing’an Mountains Region were synthetically analyzed such asRosa spp.,Actinidia spp. and so on. The results showed that the wild fruit resources in this region had important garden ornamental value, edible value and medical value. A lot of good germplasm resources and honey plant resources hadn’t been effectively protected and enough utilized. The right way of appropriate arrangement and reasonable exploitation of wild fruit resources in this region should be benefit to get rid of economic crisis early in this region. (Responsible Editor: Zhu Hong)     

Variation in cone and seed characters in clonal seed orchards of <Emphasis Type="Italic">Pinus sylvestris</Emphasis>

Cone and seed characters were observed on top, middle and bottom portions of tree crown in 3 ramets/clone in three Turkish Pinus sylvestris seed orchards. Broad sense heritability (clonal repeatability), and correlations among characters were estimated. Around one quarter of the seed production occurred in the top portion, half in the middle and one quarter in the bottom portion of the crown for all orchards. The percentage of filled seeds varied little with the crown position, indicating more or less similar levels of selfing in the bottom of the crown as in the top. The seed weight was typically 11 mg. Differences were found for studied cone and seed characters among orchards and crown positions. Variation among grafts within clone was higher than among clones for most characters. The heritability was on average below 0.5 (e.g., cone diameter, number of filled seed per cone) and rarely rose above that (e.g., cone form, length/diameter; percentage of filled seed) for any individual characters. The coefficient of variation within clones was often higher than among clones. Thus, non-genetic factors seem often more important for the variation in performance of grafts than their genetic constitution. Cone form (length/diameter) was the character where the clone influence was the strongest. Cone number and cone dry weight showed significant correlations with seed characters (numbers of total and filled seed, percentage and weight of filled seeds). Significant correlation was found between seed characters.     

Screening <Emphasis Type="Italic">Azadirachta indica</Emphasis> tree for enhancing azadirachtin and oil contents in dry areas of Gujarat,India

Azadirachta indica seed samples were collected from four different agro-ecological regions(AERs) viz.,AER-2,AER-4,AER-5A and AER-5B of Gujarat state,India during 2000 to 2002 with an aim to assess variability in azadirachtin,oil and fatty acids content of the seeds and assess correlation of these parameters with morphological characters.Azadirachtin,oil and fatty acids content indicated significant(p<0.01) variations between years and AERs in Gujarat.The azadirachtin ranged from 142 to 9 527 μg·g-1 seed kernel with an average of 2 426 μg·g-1 for the state.AER-5B recorded highest azadirachtin and oil content.Fatty acid composition was found to be affected by environmental factors particularly varying degree of annual rainfall and temperature during fruit ripening period.Conclusively trees growing in AER-5B performed better in term of azadirachtin,oil and stearic acid content.Tree girth at breast height showed no significant relation with these biochemicals.     

Genetic diversity and differentiation of fall webworm (Hyphantria cunea Drury) populations

The molecular variation and genetic relationships among five populations of the fall webworm (Hyphantria cunea Drury) in China were assessed using microsatellite technology. Ten microsatellite primers, producing polymorphic bands, were used across 300 samples. The percentage of polymorphic loci (PPB) was 98.36%; the percentage of polymorphic loci in five populations ranged from high to low in the following order: Cangzhou population, Yantai population, Qinhuangdao population, Dandong population, and Shijiazhuang population. The results showed that 34.38% of the total genetic variation of the fall webworm (GST) occurs among populations, while most variation (65.62%) exists within populations. Nei’s genetic distances ranged from 0.1386 to 0.3224. Using the unweighted pair group method with arithmetic mean (UPGMA), Nei’s genetic distances were analyzed by a clustering technique and the dendrogram shows that population differentiation is closely related to the time and geographic origin of the invasion. The major factors impacting genetic diversity of fall webworm populations are longitude, the plain area ratio, annual precipitation, latitude and time of invasion. The formation of genetic structure is correlated with characteristics of the life history and invasion ecology of the species.     

Do socio-psychological factors matter in agroforestry planning? Lessons from smallholder traditional agroforestry systems

Most of the well planned rural development forestry programs of the 1970s, and agroforestry in particular, were either not adopted by the intended beneficiaries or failed to meet the needs and aspirations of the rural people, particularly in the developing countries. The reasons for non-adoption in some cases appear to be technical, bio-physical, social and economic (termed as rational reasons by the planners), but in other situations the reasons are not so easily recognisable and comprehended (termed irrational reasons). These irrational reasons are the perceptions and attitude of the farmer towards farm practices, and their role in agroforestry planning has remained almost completely neglected. The present study is based on a household survey of the farmers in traditional agroforestry systems of Western Himalaya and investigates the importance of perceptional and attitudinal aspects of the farmers with regard to agroforestry adoption and extension. In the present study, farmers’ perceptions of restrictions on felling of trees from their own land and attitudes towards agroforestry were the most important sociopsychological factors which influenced tree growing. This study implies a need to take into account the socio-psychological factors of the farmers for planning socially acceptable agroforestry programs. The importance of study of various de jure rules and regulations controlling the use of on-farm tree resources and related exemptions and their association with farmers’ perceptions and tree growing is highlighted to develop policies to encourage tree growing in agroforestry.     

Changes in carbon stocks and tree diversity in agro-ecosystems in south western Uganda: what role for carbon sequestration payments?

Direct payments offered as compensation for adopting practices which increase carbon sequestration have implications for biodiversity conservation. This study analyzed changes in carbon stocks and tree diversity on carbon and non-carbon farmers’ plots in a pilot carbon offset project implemented by smallholder farmers in south western Uganda. On carbon farms, results indicate a respective decline and an increase in carbon density on farmlands and grasslands. On non-carbon farmers’ plots, there was an increase in both farmland and grassland carbon density. Carbon densities in farmland were significantly (t = −2.38; P = 0.023) higher than those in grasslands. There were no significant differences in tree diversity on farmlands but significant differences (species richness t = 2.18; P = 0.04; Shannon Index t = 2.92; P value = 0.0077) in grasslands. Tree diversity on carbon farmers’ plots decreased in farmlands, but increased in grasslands, while for non-carbon farmers there was a decline in tree diversity in both grasslands and farmlands. There were strong positive correlations between carbon density and tree diversity.