Plantain Cultivation Research Articles

Typology of Plantain Cultivation in a Context of Climate Change in the Agroecological Zone of Haut-Sassandra, Central-West, Côte d'Ivoire

The Haut-Sassandra region (Côte d'Ivoire), experiencing climate change with its many consequences, continues to produce bananas even if the level has fallen in recent years. This work was carried out to understand the adaptation strategies of plantain farmers facing the consequences of climate change. The methodological approach consisted of listing banana plantations of more than one hectare in Haut-Sassandra and carrying out a survey on plantain cultivation practices observed in this agroecological zone. The survey carried out made it possible to list 34 banana plantations with areas of between 1.5 and 5 hectares. For the establishment of banana plantations, slash-and-burn crops are the most favored (100%). The most used crop type is the crop association (85%) (cocoa (65%), coffee (15%) and food crops (5%)). Only 15% of banana plantations were monoculture. The fight against the wind is achieved by hedges made up of plots of rubber and teak surrounding the banana plantations. Symptoms of biotic and abiotic diseases were observed in all the banana plantations investigated. To maintain sustainability and better banana production, Haut-Sassandra planters combine several agroecological practices.

The Plantain chain (<em>Musa AAB</em>) in Caldas: consolidated governance processes

Plantain cultivation is of great importance for the country´s food security and sovereignty. In Colombia, about 87 % of the established area is associated crop and 13 % as monoculture; It is one of the subsectors that generates the highest income and employment, in 2022 960,000 direct and indirect jobs were reported. In the Caldas department, plantain is cultivated in all municipalities, its value chain, its main actors, flows, synergies, and governance spaces around this productive system were analyzed. For this purpose, a mapping of local actors was used with a Social Network Analysis, a description of the de facto banana value chain and it was analyzed under the Governance Analytical Framework. There is evidence of a productive system with well differentiated areas in terms of technological development, integration of chain links, articulation of institutions, organizational processes, access to national and international markets, and agro-industrial transformation processes. The articulation and cooperation between inter-institutional actors have been critical for development of collective actions to optimize resources, time, processes, and maximize the generated impact. The Caldas roundtables competitiveness emerge and position themselves as a consolidated space for territorial governance, which in turn catalyzes articulation dynamics and institutional interventions to enhance the resources of value chains and territories.

Exploitation of plantain (Musa spp.) plantations as an agrotourist element

Objective: To analyze the processes and alternative uses that plantain cultivation may have, in addition toplaces with tourist potential in the town Monte Salas, municipality of Fortín de las Flores, Veracruz, Mexico.Design/Methodology/Approach: A review of the space of the study area was performed, as well as ananthropological analysis, description of the process of the plantain leaf used to prepare local food, commercialanalysis, development of a sustainable product, and a research stay in Colombia.Results: In Monte Salas, Fortín de las Flores, Veracruz, Mexico, plantain cultivation is regarded as anoutstanding element of the landscape, together with the process of leaf roast production as a value-addingstrategy to generate biodegradable co-products. Through the dissemination of audiovisual capsules on socialnetworks, places with tourist potential were made known and together with the implementation of the offer ofbiodegradable co-products, it was demonstrated that plantain leaf can be used alternately.Study Limitations/Implications: Due to the SARS-CoV-2 (COVID-19) coronavirus pandemic, the dissemination of our findings and products were restricted.Conclusions: Novel biodegradable products can be manufactured from plantain leaves, which created aspecial interest of local tourists to visit Monte Salas and enjoy the agrosystemic landscape.

Differential impact of altitude and a plantain cultivation system on soil macroinvertebrates in the Colombian Coffee Region

Macrofaunal composition in four plantain cropping systems in the municipalities of Armenia, Calarcá, and Circasia in Colombia was evaluated by measuring species richness, abundance, biomass, and variation in these parameters in relation to altitude and cropping system at 33 farms. The DPSIR (Driver-Pressure-State-Impact-Response) model was used to evaluate the impacts of management practices on crops and their repercussions for edaphic fauna. Fourteen orders, three classes, and eight families of macrofauna were identified. The results indicate that type of cropping system influences the composition of edaphic communities, mainly through the altitudinal gradient. Fifteen species of earthworms were found, seven exotic and eight native. The greatest number of species (12) was found in systems consisting of plantains associated with coffee (AC), followed by the traditional system (TA) with 10, plantain trees (AA) with nine, and monoculture (MONO) with eight species, of which the most abundant was Pontoscolex corethrurus. In our findings, it was possible to differentiate plantain cultivation systems according to the type of management practice and the intensity and frequency of application of agrochemicals by farmers on farms. The DPSIR framework permitted differentiation among cropping systems, visualizing agroecosystems that tolerate the presence of accompanying vegetation. Variables that exert pressure and provide options for differentiating the systems were also identified. DPSIR facilitates the understanding of cropping systems and has great potential for use in agroecosystem planning in rural areas.

Estimation of Heavy Metals and Polycyclic Aromatic Heavy Metals in Harvested Plantains from Bodo, Rivers State

A Plantain harvested from Bodo community, Gokana L.G.A Rivers state were analyzed for heavy metals and Polycyclic Aromatic Hydrocarbons (PAHs) concentrations. Physicochemical properties of the agricultural soil used for the plantain cultivation showed the following: pH (5.7) while the control experiment was seen at 7.4. Soil conductivity of 721 and 398 were obtained for both the test and control experiments, respectively. Soil mineral contents: Potassium (6.88 mg/g), phosphorus (2.63 mg/g), Magnesium (12.42 mg/g), chloride ions (1021.21 mg/g). Heavy metal analysis of the soil showed a greater proportion of copper and iron in while Hg, As and Cd were below detectable limit in both tested samples. Pb was found relatively in lower concentrations of 24.12 mg/g in the test sample, 6.23 mg/g in the control experiment. Total Oxidizable Carbon Content (TOC) and Total Petroleum Hydrocarbon (TPH) content of the soil were observed at 104.12 and 2567 mg/g respectively in the tested sample. The control experiment showed TOC and TPH concentrations of 42.85 and 1094 mg/g. Heavy metal analysis of harvested plantain from Bodoh community showed the presence of the following: Lead (Pb), Iron (Fe) and Copper (Cu) in the following order: Cu>Fe>Pb in the test sample while in the control experiment, iron (Fe) was seen greater than copper (Cu). Heavy metals of mercury, cadmium and arsenic were below detectable limit at in both the harvested plantain from Bodo community and those of the control experiment, respectively. Bioaccumulation factor of all the heavy metals identified were <1. PAHs of Acenaphthalene, Acenaphthene, chrysene, pyrene and fluranthene were not detected in the control experiment while only chrysene was not detected in the test samples. Naphthalene,methyl naphthalene, acenaphthalene, acenaphthene, benzo (k) fluranthene and flourene were relatively high in concentration than pyrene and flouranthene in the test samples. Naphthalene, methylnaphthalene, flourene and benzo(k) flouranthene were only recorded in the control experiment. Acenaphthalene (0.034 mg/g) was seen as the highest PAHs in bioaccumulation in the test sample while flourene (0.005 mg/g) recorded the highest in the control experiment.

English

Plantain prices in sub-Saharan markets are very high due to the fact that the supply does not cover the large demand. The main constraint of plantain cultivation is the seedlings unavailability in quantity and quality, which is essential to boost the creation of new plantations. The PIF technique could solve this problem if its substrate of production is amended with natural products for quality enhancement. This study aims to assess clam shells and Tithonia diversifolia effects on the growth of PIF plantain seedlings and their sensitivity to Mycosphaerella fijiensis. Plantain PIF seedlings were grown in an amended substrate. The treatment influences the seedlings germination rate, number of shoots, height, diameter, area of leaves and favours a less sensitivity to M. fijiensis compared to the controls. The presence of clam shells and T. diversifolia in the treatment especially enhanced the (1) vegetative growth and (2) less sensitivity as well as accumulation of proteins and polyphenols respectively. This combination shows a synergic action with dual role both as a biofertilizer and as a biopesticide. This work valorises the use of by-fishing products and bad herbs that are environmentally benign and affordable to poor smallholders&rsquo; farmers, leading to a sustainable and responsible agriculture, as well as poor peasants&rsquo; empowerment. Key words: Plantain (Musa spp.), PIF seedlings, Tithonia diversifolia, clam shells, biofertilizer, biopesticide, Mycosphaerella fijiensis. &nbsp; &nbsp

VERTICAL LAYERS OF TITHONIA DIVERSIFOLIA FLAKES AMENDMENT IMPROVES PLANTAIN SEEDLING PERFORMANCE

Plantain seedlings availability in sub-Saharan countries are very weak to support a high productivity level required. The plantain cultivation faces problem of the seedling’s unavailability in quantity and quality for intensification of this crop. The amendment of PIF substrate production with natural products could be an alternative to this problem. This study objective is to evaluate the effect of vertical layers of Tithonia diversifolia flakes on the performance of PIF plantain seedlings in terms of vegetative growth and susceptibility to black Sigatoka disease (BSD) in nursery. The vertical layer of T. diversifolia flakes amendment was introduced in the propagator in the presence of the control without amendment in controlled and uncontrolled conditions for shoots, then seedlings generation, followed by the evaluation of the vegetative growth parameters, the inoculation of the leaves with Mycosphaerella fijiensis and the pool of biomarkers evaluation. The treatment increases the germination rate, the number of shoots, the height and the diameter of shoots, the area of leaves as well as the seedlings roots, but also protects the seedlings against BSD up to about 56% compared to the controls. It also enhances the accumulation of proteins, polyphenols content and enzymes such as peroxidase, polyphenoloxidase and glucanase. The dual role of the vertical layer of T. diversifolia flakes in seedling production as a biofertilizer and as a biopesticide was revealed in this research. Taking into account this bad herbs flakes as a tool for sustainable and green agriculture is an open door to poor peasants for their empowerment.

English

Plantain is one of the most important sources of food in the African lowlands stretching from the lowlands of Guinea and Liberia to the central basin of the Democratic Republic of Congo (DR Congo). Because plantain cultivars do not produce seeds, plantain cultivation is based on vegetatively transplanted lateral shoots/suckers. The way by which plantain reached the African continent is still under speculation. The aim of this study was to shed light on the history of plantain cultivars through a linguistic/synonymy study in northern Democratic Republic of Congo. We report the diversity of plantains in 18 villages across the Bas-Uele province based on a survey. Three villages in which plantain production systems dominated were selected in each territory, and ten households were consulted in each village. In each selected village, a focus group discussion was conducted with a group of at least 30 men, and with a separate group of 30 women to establish a list of plantain cultivars grown and known. A total of 46 cultivars were identified and 294 synonyms detected. The cultivar names are mostly related to animal features and agronomic traits, although there is a need to revisit the list for more specific traditional names. The local differences in cultivar identity, density and distribution are explained partly due to the influence of humid forest versus savanna landscapes, but the main part seems to be due to previous movements of Benza, Boa, Ngbandi, Rambo and Zande ethnic groups with their own set of cultivars. We demonstrate that the recorded synonymy data are useful for a tentative partial reconstruction of the history of some cultivars. This is useful for the genetic improvement of plantain cultivars, which most probably will have to rely for a great deal on the unraveling and management of epigenetic mechanisms. Key words: Bas-Uele, cultivar, diversity, ethnic group, plantain, synonymy.

Evaluación de tres alternativas de fertiriego en el establecimiento del cultivo de plátano (musa paradisiaca/harton cv) en el Yopal, Casanare

En la actualidad es necesario implementar en la agricultura métodos de manejo racional del recurso hídrico. El cultivo de plátano requiere altos contenidos de agua y fertilizante. El fertiriego es una alternativa para suplir requerimientos hídricos y a la vez fertilizar la planta. La región de los llanos orientales se caracteriza por suelos franco-arcillosos, poco permeables y de velocidad de infiltración lenta. Lo que hace que la disposición de fertilizantes se localice en superficie del terreno, dificultando su paso hacia la zona radicular. En la presente investigación se evaluó en etapa de establecimiento tres alternativas de fertiriego (T1: subterráneo, T2: goteo, T3: drench). Se estableció un lote experimental compuesto por 30 unidades experimentales para cada tratamiento. La Lámina Rápidamente Aprovechable (LARA), se estableció teniendo en cuenta el Punto de Marchitez Permanente (PMP), la Capacidad de Campo (CC), la Profundidad Radicular (PR) y la densidad aparente (DA). Los requerimientos de fertilización se estimaron a partir de análisis de suelos. Las variables de respuesta fueron el número de hojas, diámetro del tallo, altura de la planta y peso de la planta. Para el ANOVA se utilizó un DCA y los datos fueron analizados en INFOSTAT mediante una prueba LSD Fisher con un valor p valor de 0.05. Se encontraron diferencias significativas entre los tratamientos, en donde el tratamiento de fertiriego subterráneo mostró mayores valores respecto a las variables de seguimiento. En este trabajo se encontró que la alternativa de fertiriego subterráneo podría ser una solución viable para un manejo eficiente del agua y fertilización en el cultivo de plátano, posiblemente a que esta alternativa dispone de manera local el agua y los nutrientes para la planta.

Low genetic diversity of Banana bunchy top virus, with a sub-regional pattern of variation, in Democratic Republic of Congo.

Banana bunchy top virus (BBTV), belonging to the genus Babuvirus, is the most devastating and widespread banana virus. Banana and plantain are major crops in terms of household income and food security in Democratic Republic of Congo (DRC). Despite the large area under banana and plantain cultivation in the country, before this study, the genetic characterization of BBTV isolates had only been undertaken for two provinces. In the study presented here, genetic variation in BBTV was assessed from 52 BBTV isolates collected in five out of 11 provinces in DRC (Bandundu, Bas-Congo, Katanga, Kinshasa and Kasaï Oriental) and in two provinces using sequences previously described in databases. Full genome sequencing of DNA-R components was performed, revealing low genetic variation (98-100% nucleotide identity) among the BBTV isolates detected. The phylogenetic analyses showed that all the DRC isolates were clustered in the South Pacific clade of BBTV. Based on the coding region for the replication initiator protein, haplotype diversity was estimated to be 0.944±0.013, with 30 haplotypes from 68 isolates in DRC. Such diversity shows a haplotype distribution mainly at the sub-regional level in DRC. In addition, the sequence determination from the whole genome of selected isolates confirmed low genetic variation among isolates from seven DRC provinces (97-100% nucleotide identity). This study strengthened the hypothesis of a single BBTV introduction some time ago, followed by the spread of the virus in the country.

Effects of Demographic Factors on Plantain Production in Southern Part of Edo State, Nigeria

This study examined the effects of demographic factors on plantain production in Edo State, using Ovia Northeast Local Government Area as a case study. Primary data were collected with a multistage sampling procedure. Ten (10) plantain farming communities (Utese, Uhen, Egbeta, Ogbese, Okada, Iguomo, Aghanokpe, Ugbuwe, Ofunwengbe and Ugboke) were purposely selected and fifteen (15) plantain farmers were selected randomly from the communities to get a total of one hundred and fifty (150) respondents. Data were analysed using descriptive and regression statistics. The Findings revealed that majority (66%) of the farmers were male, with average farm size of 2.63hectares, mean age of farmers at 40 years, educational level of secondary school, farming experience of between 11 and 20 years respectively. The regression analysis shows that education level (0.255), marital status (0.149), farm size (0.666) and farming experience (0.603) coefficients were positive, an indication that these variables have direct effect on plantain production in the study area. About 55.7% variation in the farmers output were explained by the demographic factors which also are confirmed by F-ratio (25.489) that is significant at -level of probability. Based on the findings, government should facilitate policies towards education of farmers, subsidize alternatives to labour for farm activities and enhance availability of arable land to plantain farmers in Edo state. I. Introduction: Plantain (Musa ssp.) belongs to the family Musaceae. The crop is widely grown all over the World and its production in Africa is estimated at more than 50% of the World production (FAO, 1990). Majority (82%) of the plantain output in Africa are produced in the low land of Guinea, Liberia to the central basin of the Democratic Republic of Congo. About 70 million people in West and Central Africa derives more than 25% of their carbohydrates from the consumption of plantain, making it one of the major sources of energy in Africa (Swennen, 1990). Food and Agricultural Organisation (FAO, 2007) noted that Nigeria is a major producer of plantain in West and Central Africa and ranked fifth highest producer in the World. Plantain consumption in Nigeria in different forms is on the increase because of its high nutritional value, implying the existence of increased market potential for its production. However, plantain output (80%) is left in the hands of subsistence rural farmers (Bayeri, 1996). According to Adesanya, (2008) plantain is consumed in the World today in the form of boiled or roasted, plantain flour, chips and so on. These forms which are widely consumed are rich in protein (1.2%), carbohydrate (35%) and ash (0.8%). It is used in the prevention of kwashiorkor (Idachaba, 1995). The crop ranked third among starchy staples in Nigeria after cassava and yam. It is a major source of carbohydrate to man and domesticated animals. According to Ndubizu, (1995) plantain is said to have advantage of short gestation period of between 14 - 20 months with rapid multiplication ability (suckers) and as such several harvest can be made from one planting unlike other permanent crops. It fruits the year round. Research evidence has shown that plantain cultivation is still largely at the subsistence level within the forest zone of sub - Saharan Africa. The continuous availability of harvested bunches from established plantations makes it possible for the crop to contribute to year round food security and income for farmers. This may be particularly important when seasonal conditions create period of food shortages and other crops are in short supply. The interest of this study premised on the fact that the crop has the capacity to bridge the supply gap of carbohydrate when in high demand especially when other starchy staples are unavailable or difficult to harvest in the dry season. Hence this study focuses on the effects of demographic factors on plantain production in Edo State. II. Methodology: Study Area: The Study was carried out at Ovia Northeast Local Government Area (LGA) of Edo State. The LGA lies between latitude 6 0 -6.9 0 N and longitude 5.5 0 - 5.9 0 E in the North, while it extends through longitude 5.5 0 - 5.6 0 E in the South, with a population of about 153, 849 people and a land mass of 2, 357, 225 square kilometers, with an annual maximum temperature of 30 and minimum of 22℃. The annual average

Natural Occurrence of Banana bunchy top virus in Ensete superbum in India

The genus Ensete belongs to the family Musaceae of the order Zingiberales is grown throughout Africa and Southern Asia and contains as many as nine species. Ensete superbum (Roxb.) Cheesman, (2n = 18) commonly known as Ensete, is a large herb grown in India. The plant is well-known in the Western Ghats [2], Anaimalai hills, Sirumalai hills, Lower Pulney hills and other parts of the peninsular India. Banana bunchy top virus (BBTV; Genus Babuvirus; Family Nanoviridae) is a phytopathogenic virus associated with bunchy top disease of banana has become a major threat to banana and plantain cultivation in India and in several tropical regions of the world and cause significant yield losses [1]. The virus is phloem-limited and transmitted by the banana black aphid, Pentalonia nigronervosa (Coquerel) in a persistent circulative and non-replicative manner. The host range of BBTV is confined to Musa spp. In this paper we report natural occurrence of BBTV in Ensete in India. Samples of Ensetesuperbum plants exhibiting symptoms of intermittent dark green dots, dash, streaks of variable length like ‘Morse code’ pattern on leaf sheath, midrib, leaf veins and petioles and bunching of shorter and narrow leaves giving the appearance of bunchy top disease of banana were collected during December, 2011 from a garden in Coimbatore, TN (Fig. 1a, b). These Ensete plants also infested with banana black aphid. Aphids collected from symptomatic Ensete plants and healthy plants were transferred to healthy tissue culture raised Grand Nain banana plantlets for 48 h inoculation access. The inoculated plants were maintained in an insect-proof growth chamber maintained at 25 ± 0.5 °C and 12 h light/dark photoperiod. Fig. 1 a Bunchy top symptoms associated with Ensete superbum; the leaves are short and narrow; Insert: Dark green Morse code like streaks on midribs. b Closely packed leaf petioles bunching at the top. c Neighbor-joining tree based on the deduced amino acid ... The presence of the virus in symptomatic leaves of Ensete was confirmed by direct antigen coating (DAC) ELISA using BBTV polyclonal antiserum and the healthy leaf of Ensete was negative. Total DNA from the symptomatic Ensete plants and aphids were extracted by the modified CTAB method [3]. PCR was performed using primer specific for replicase gene (Rep) (RSREPFP: 5′-TTGGATCCATGGCGCGATATGTGGTATGC-3′ and RSREPRP: 5′-TTGGATCCATGGCGCGATATGTGGTATGC-3′) and coat protein (CP) gene (RSCPFP: 5′-ATGGCTAGGTATCCGAAGAAATCC-3′ and RSCPRP: 5′-TCAAACATGATATGTAATTCTGTTC-3′) of BBTV [4] which resulted with expected amplicon of sizes 861 and 513 bp, respectively in both the symptomatic plant sample and aphid sample. The purified PCR product was cloned and sequenced. The CP and Rep gene sequences of isolate obtained in this study were deposited in NCBI GenBank ({type:entrez-nucleotide,attrs:{text:JX171699,term_id:468862107,term_text:JX171699}}JX171699; {type:entrez-nucleotide,attrs:{text:JX197072,term_id:468862123,term_text:JX197072}}JX197072). 16 out of 20 inoculated banana plantlets expressed typical BBTD symptoms such as choked plant top with a rosette of narrow, short leaves, short dark green dots and dashes on midrib and the leaf veins 25 days after inoculation, whereas aphids from healthy Ensete plants did not produce any symptom on inoculated banana. The CP gene sequence of Ensete bunchy top isolate shared 95–99 % sequence identity with the BBTV isolates of South Pacific group and 90–94 % sequence identity with the isolates of Asian group. The Rep gene sequence of Ensete bunchy top isolate showed 97–99 % sequence identity with the South Pacific group isolates and 92 % sequence similarity with the Asian group isolates. In phylogenetic analysis based on the amino acid sequence of the CP gene, the Ensete bunchy top isolate grouped with BBTV isolates of Shevaroys and Kolli hills (TN) and formed a separate cluster (Fig. 1c) whereas remaining Indian BBTV isolates formed the core of South Pacific group. Wanitchakorn et al. [5] reported high degree of divergence in the sequence of CP gene of Asian group. Phylogenetic analysis based on amino acid sequence of the Rep gene of Ensete bunchy top isolate showed that this isolate grouped with isolates of Tamil Nadu, Maharashtra and Andaman (data not shown). Both Ensete and wild valuable diploid bananas are conserved naturally. Infected plants of Ensete need to be identified and eradicated so as to protect the wild bananas in Western Ghats and other hill regions. An interesting finding of this study is that the Ensete bunchy top isolate is distinct based on amino acid sequence of CP gene and grouped with the BBTV-hill isolates of Tamil Nadu. Selvarajan et al. [4] distinguished the hill isolates of BBTV of TN with the isolates occurring in other hilly regions of India. Possibly this Ensete isolate would have originated from hill regions of Tamil Nadu. To the best of our knowledge, this is the first report of natural occurrence of BBTV infecting Ensetesuperbum in India.

SCREENING MUSA GENOTYPES FOR BANANA BUNCHY TOP DISEASE RESISTANCE IN BURUNDI

The original publication is available at www.actahort.org. Banana bunchy top disease (BBTD), caused by the Banana bunchy top virus (BBTV), is reported as one of the most devastating diseases affecting banana and plantain cultivation worldwide. In order to identify putative sources of resistance, a cultivar screening trial comprising 40 Musa genotypes was established in March 2007 at the ISABU Mparambo research station in northwestern Burundi (893 m a.s.l.). Dessert bananas (AAA group), East African highland bananas (AAA, EAHB), plantains (AAB), cooking bananas (ABB), a tetraploid hybrid and wild diploid bananas (Musa acuminate and Musa balbisiana) were assessed. Ten plants per genotype were planted in a completely randomised design with border rows consisting of BBTV-infected 'Yangambi Km 5' (AAA) plants. Colonies of Pentalonia nigronervosa collected in BBTV-infected fields were released in the plot to enhance disease spread. Twenty-eight months after trial establishment, 32 genotypes have shown typical banana bunchy top symptoms. The first symptoms appeared 80 days after trial establishment on 'Yangambi Km 5'. Twenty-eight months after trial establishment, only eight genotypes [Musa balbisiana type Tani (BB), 'Kayinja' (ABB), 'FHIA-03' (AABB), 'Prata' (AAB), 'Gisandugu' (ABB), 'Pisang Awak' (ABB), 'Saba' (ABB) and 'Highgate' (AAA, Gros Michel subgroup)] have not manifested typical disease symptoms on any of the ten plants per genotype. Plant samples taken from these visibly healthy cultivars and analysed at a molecular level [at the Faculte Universitaire des Sciences Agronomiques de Gembloux (FUSAGx) in Belgium] indicated the presence of the virus in 'Pisang Awak', 'Saba' and 'Highgate'. These genotypes can be considered as BBTD tolerant. They could potentially act as a reservoir for the virus. Further diagnostic tests will be carried out on the five BBTV-free genotypes to confirm the extent of latent infections. Preliminary results indicate that genotypes with one or two B genomes tend to be more tolerant to BBTD.

Pesticide application practices, pest knowledge, and cost-benefits of plantain production in the Bribri-Cabécar Indigenous Territories, Costa Rica

The use of pesticides in the cultivation of cash crops such as banana and plantain is increasing, in Costa Rica and worldwide. Agrochemical use and occupational and environmental exposures in export banana production have been documented in some parts of Central America. However, the extent of agrochemical use, agricultural pest knowledge, and economic components in plantain production are largely unknown in Costa Rica, especially in remote, high-poverty areas such as the Bribri-Cabécar Indigenous Territories. Our objective was to integrate a rapid rural appraisal of indigenous farmer pesticide application practices and pest knowledge with a cost-benefit analysis of plantain production in the Bribri-Cabécar Indigenous Territories, for the development of better agricultural management practices and improved regulatory infrastructure. Interviews conducted with 75 households in 5 indigenous communities showed that over 60% of participants grew plantain with agrochemicals. Of these plantain farmers, over 97% used the insecticide chlorpyrifos, and 84% applied nematicides, 64% herbicides, and 22% fungicides, with only 31% of participants reporting the use of some type of protective clothing during application. The banana weevil ( Cosmopolites sordidus Germar) was ranked as the most important agricultural pest by 85% of participants, yet only 28% could associate the adult and larval form. A cost-benefit analysis conducted with a separate group of 26 plantain farmers identified several national markets and one export market for plantain production in the Indigenous Territories. Yearly income averaged US$6200/ha and yearly expenses averaged US$1872/ha, with an average cost-benefit ratio of 3.67 for plantain farmers. Farmers applied an average of 9.7 kg a.i./ha/yr of pesticide products and 375 kg/ha/yr of fertilizer, but those who sold their fruit to the national markets applied more nematicides, herbicides, and fertilizers than those who sold primarily to export markets, suggesting a lack of appropriate application knowledge. Results indicate that the quantity of agrochemicals applied in plantain cultivation is less than that applied in export banana, but the absence of appropriate agrochemical application practices in plantain cultivation may pose serious risks to human and environmental health. Culturally appropriate farmer education and certification programs are needed as well as the development of safe-handling practices, regulatory infrastructure, and adequate agrochemical storage, transport, and waste disposal facilities. Long-term solutions however, are dependent on the development of policies and infrastructure that support non-chemical pest management, alternatives to pesticides, and the identification of organic plantain markets.

Dispersión de Ralstonia solanacearum en suelos cultivados con plátano en el Piedemonte Llanero

La dispersión de la enfermedad del Moko en un cultivo comercial de plátano se determinó a partir de un análisis de la incidencia en cuadrantes conformados por ejes de ocho plantas a partir de una planta enferma erradicada (foco). Se identificaron colonias de Ralstonia solanacearum en muestras de agua y suelo procedentes de 12 puntos por cuadrante, en cuatro muestreos realizados los días 0, 45, 90 y 135. Los aislamientos que formaron colonias típicas fluidas (F), pequeñas redondas fluidas (SFR) y variantes afluidas (AFV), fueron sometidos a pruebas bioquímicas, análisis molecular (PCR), reacción de hipersensibilidad en hojas de tabaco y patogenicidad sobre plantas jóvenes de plátano. La enfermedad se incrementó de 8 a 10, 12 y 38 plantas en promedio por cuadrante y muestreo. En tres de los cuadrantes la incidencia se restringió al área más cercana al foco, mientras que en el otro hubo una dispersión mayor. El número promedio de colonias típicas (F) aisladas varió de 54 el día 0 a 114, 142 y 90 en los muestreos subsiguientes. El número de unidades formadoras de colonia por gramo de suelo (UFC/g) de los tipos F y SFR siempre fue menor que el de colonias AFV; las de tipo F tendieron a disminuir a partir del tercer muestreo (día 90) registrando un leve aumento en el cuarto (día 135). Por su parte, el número de UFC/g tipo SFR aumentó en los muestreos segundo y tercero y se redujo en el último. El número de UFC/g de tipo AFV, aunque 10 veces más abundante que los otros tipos, presentó un comportamiento similar al de las colonias SFR y su disminución fue más drástica al final. Las colonias tipo F fueron más frecuentes en cercanías del foco, lo que coincidió con el incremento de plantas enfermas, mientras que las colonias tipo AFV predominaron en las áreas intermedias. La amplificación de segmentos de ADN por PCR (Oli1 – Y2) confirmó los resultados de las caracterizaciones bioquímica, de hipersensibilidad y patogénica. Las colonias tipo F presentaron mayor número de respuestas positivas que las SFR y AFV a cada una de las pruebas, incluyendo la de patogenicidad.

Assessing Passive Capillary‐Wick Samplers for monitoring resident nitrate concentration in real field

Abstract. We evaluated the effectiveness of capillary‐wick samplers (PCAPS) for continuous monitoring of resident nitrate concentration in three ‘soil‐crop‐climate’ systems differing in soil type, land use and climate. These systems involved: (i) acid silty soils under a beech‐oak forest affected by heavy N‐NH4+ deposition in Belgium; (ii) silty soils under wheat cropping and a short rotation willow coppice plantation (SRC) in Belgium; and (iii) volcanic ash soils under plantain cultivation with and without urea fertilization in Colombia. The PCAPS continuously applied a suction of 0 to 5.4 kPa to the soil water below the effective rooting zone without the need for an auxiliary vacuum source. The nitrate concentrations showed large variations over time and ranged between 6–192 mg l–1 under forest, 19–143 mg l–1 under wheat, 11–47 mg l–1 under SRC and 3–138 mg l–1 under fertilized plantain. The analysis of the soil leachates collected with PCAPS confirms previous results dealing with leaching of nitrate and alkaline and alkaline‐earth cations in similar ‘soil‐crop‐climate’ systems. It was concluded that PCAPS was a suitable tool to collect soil solutions and that it could help to assess nitrate leaching losses in various ecological or cropping conditions.

Characteristics, classification, and agricultural potential of some Niger delta soils in Nigeria

Nine pedons representing the major soils of an 80,000 ha area in Yenagoa, Niger Delta, Nigeria, were classified and evaluated for maize, plantain and oil palm cultivation. The soils were identified as low activity clay (LAC) Ultisols (Kanhapludult and Kandiudult) or Acrisols (FAO, UNESCO) with hydromorphism reaching the A‐horizon in most cases. They were mainly derived from alluvial materials. The presence of an argillic B‐horizon in all the pedons indicated that the depositions were not recent. Most of the soils were sandy at he top but clayey in the subsoils although a few have either sandy or clayey texture throughout the profile. Organic matter content in the A‐horizon was 2.30–4.50%. The pH was between strongly acidic (3.5) to slightly acidic (5.0). The CEC in the B‐horizon was low (<24 cmol kg‐1) in the sandy soils and moderate (>24 cmol kg‐1) in the clayey soils. The exchange complex was dominated by Ca (2–17 cmol kg‐1), followed by Mg (1–8 cmol kg‐1), while K was low (0.07–0.22 cmol kg‐1) to fairly high (>0.66 cmol kg‐1). The base saturation was just moderate (50–92%). The soils were marginally suitable (S3) for maize, with about 20% of the area not suitable (N1) presently. The main constraints to arable cultivation were heavy rainfall, imperfect or poor drainage, and low base saturation. They are moderately suitable (S2) for plantain due to low base saturation, short dry season, and unfavorable texture which was light in some and too heavy in others. For oil palm, the soils were moderately (S2) to highly (S1) suitable, though the short dry season, low base saturation and poor drainage could pose as limitations. Obviously, with good drainage and proper fertility management high yields of maize, plantain and oil palm could be obtained on these soils. Such studies should be made to cover the entire Niger Delta in order to provide data to justify the preservation of all prime agricultural soils in the area from being lost to the oil industry.

Effect of the black sigatoka resistance locus bs 1 and ploidy level on fruit and bunch traits of plantain-banana hybrids.

Plantain (Musa spp., AAB group) cultivation is threatened by black sigatoka, an airborne fungal (Mycosphaerella fijiensis Morelet) leaf spot disease. Several traits in plantains and bananas are mainly affected by major genes. The host resistance response to black sigatoka is under the control of at least three different genes, one major recessive gene bs1 and two other independent additive alleles. Diploid and tetraploid plantain hybrids were evaluated for bunch weight, fruit weight, fruit length and fruit circumference. The F1 euploid hybrids were derived from interspecific crosses between the resistant diploid wild banana ‘Calcutta 4’ and the susceptible triploid plantain cultivars ‘Obino l'Ewai’ and ‘Bobby Tannap’. Linear and multiple regression models, coefficients of determination, and Durbin-Watson statistics were used to determine the single and combined effects of the major locus for black sigatoka resistance and ploidy on the different traits in the progenies. Differences in yield were mainly due to changes in weight and girth of fruit, which are affected by black sigatoka disease. The combined effect of ploidy and resistance to black sigatoka was partially responsible for the quantitative trait variation in yield. As a result of the gene interaction in the black sigatoka resistance locus bs1, the partially resistant and less susceptible phenotypes showed higher yield than their more susceptible full sibs.

Yield loss in plantain from black sigatoka leaf spot and field performance of resistant hybrids

Plantain ( Musa spp., AAB group) cultivation is threatened by black sigatoka ( Mycosphaerella fijiensis Morelet), an airborne fungal leaf spot disease. Several black-sigatoka-resistant tetraploid hybrids have been developed by the International Institute of Tropical Agriculture (IITA). Resistance and yield performance of three hybrids were evaluated and compared with the maternal triploid plantain cultivar Obino l'Ewai with and without fungicide treatment. Plantain yield loss from black sigatoka was 33%, as calculated from the difference in yield between the fungicide-treated and non-treated plantain (23.5 and 15.7 t ha −1, respectively). Yield loss ensued from a reduction in the number of fruits per bunch and lower fruit weight. Black sigatoka also caused delayed flowering and harvest, and premature fruit ripening. Sigatoka evaluation at flowering indicated significantly less leaf spot damage in the three hybrids (TMPx 548-4, 548-9 and 597-4) as compared with the susceptible plantain. At harvest, however, hybrid TMPx 597-4 displayed a susceptible response, whereas hybrids TMPx 548-4 and 548-9 still showed field resistance. These two hybrids also had improved agronomic traits, such as high yield, shorter stature, earlier maturity and better suckering. Yield of TMPx 548-9 (33.5 t ha −1) was 43% higher than that of the fungicide-treated and twice that of the non-treated plantain, suggesting that its higher yield was due not only to black sigatoka resistance, but also to heterosis. TMPx 597-4 had poor yield performance (12.7 t ha −1), indicating that tetraploidy per se does not increase yield.

Oligonucleotide and amplification fingerprinting of wild species and cultivars of banana (Musa spp.).

DNA oligonucleotide and amplification fingerprinting have been successfully used to detect genetic polymorphisms in 15 representative species and cultivars of the genus Musa, comprising AA, AAA, AAAA, AAB, ABB, and BB genotypes. In-gel-hybridization of Hinf I-digested genomic banana DNA to the 32P-labeled synthetic oligonucleotides (GATA)4, (GTG)5, and (CA)8 revealed considerable polymorphisms between Musa species and cultivars. The fingerprint patterns proved to be somatically stable and did not show differences between individual plants of 'Grand Nain' (AAA genotype). Dendrograms based on oligonucleotide fingerprint band sharing data proved to be consistent with most of the known features of the history of banana and plantain cultivation and evolution, respectively. DNA samples from the same banana species and cultivars were also amplified by PCR using single or pairwise combinations of short oligonucleotide primers. Amplification products were separated on agarose or polyacrylamide gels and visualized by ethidium bromide or silver staining, respectively. Polymorphic patterns were obtained with some but not all primers. By using the CCCTCTGCGG primer in simplex and/or duplex PCR, the induced mutant 'GN60A' was clearly recognized from its original variety 'Grand Nain'. Both fingerprint techniques allowed the detection of bands characteristic for the A and B genome. This DNA fingerprinting technology has potential application in several areas of Musa improvement.