Banana Plantations Research Articles

First Report of Leaf Spot Caused by Colletotrichum citricola on Cavendish bananas in China.

Cavendish banana (Musa spp. AAA group) is an important tropical and subtropical fruit with significant economic value. It is widely planted in Guangxi, Yunnan, Hainan, Fujian and Guangdong provinces in China. In November 2020, leaf spots were observed on nearly 80% of the plants growing in three Cavendish banana plantations in Chongzuo, Guangxi, China. The symptoms on Cavendish banana leaves initially appeared as small black necrosis spots, which gradually expanded and connected, eventually covered the entire leaf. Three diseased leaves from three plantations were collected, sectioned into small pieces (5 ×5 mm), surface sterilized (10 s in 75% ethanol, followed by 1 min in 1% sodium hypochlorite and rinsed three times in sterile water) and placed on potato dextrose agar (PDA) at 28℃ for 5 days for pathogen isolation. The fungal colonies were white, cottony, while the reverse sides were white, concentric circles with yellowish-brown discoloration in 7-day cultures. The conidia were hyaline, aseptate, cylindrical, oval, measuring 10.3 to 17.71 μm (mean 14.06 ± 1.45 μm; n = 200) in length and 4.48 to 9.57 μm (mean 7.46 ± 0.69 μm; n = 200) in width. Three representative isolates (DX1-5, LZ4-5, and FS1-3) were obtained by monosporic isolation. The partial internal transcribed spacer (ITS) regions, actin (ACT), chitin synthase (CHS-1), glyceraldehydes-3-phosphate dehydrogenase (GAPDH), calmodulin (CAL), and β-tubulin (TUB2) were amplified from genomic DNA for the three isolates (Weir et al. 2012). The sequences of the amplified fragments were deposited in GenBank (accessions OL361844 to OL361858, for GAPDH, CAL, ACT, CHS-1, and TUB2 of isolate DX1-5, LZ4-5 and FS1-3; OL305066 to OL305068 for ITS) and showed over 99% identities with the corresponding sequences of C. citricola. A neighbor-joining phylogenetic tree based on the above six genes of type or ex-type specimens of Colletotrichum (Fu et al. 2019) was constructed with MEGA 5.2 using the concatenation of multiple sequences (Kumar et al. 2016). All three isolates clustered together with the type culture of C. citricola (CBS 134228, CBS 134229, CBS 134230) with 82% bootstrap support in the phylogenetic tree. According to the molecular and morphological characteristics, all three isolates were identified as C. citricola. Pathogenicity tests were conducted on one-month-old primary hardened tissue culture plantlets. Tender, healthy leaves were gently scratched with a sterile needle, and each wound site was inoculated with sterile cotton impregnated with conidial suspension (106 spores/ml) for each isolate. Wounded leaves were treated with sterile cotton impregnated with conidial suspension of C. fructicola as positive controls and sterile water as negative controls. Each isolate was inoculated with three tissue culture plantlets, six inoculated sites on each plantlet, the same as controls. All inoculated tissue culture plantlets were covered with plastic bags to maintain high humidity and placed in a 28℃ growth chamber with constant light. Black necrotic lesions were clearly observed on the inoculated leaves and the positive controls after 7 days, whereas no symptoms appeared on the negative control leaves. The fungus was re-isolated from inoculated leaves, and these isolates matched the morphological and molecular characteristics of the original isolates confirming Koch's postulates. To our knowledge, this is the first report of leaf spot caused by C. citricola on Cavendish banana worldwide.

Bacteria not fungi drive soil chemical quality index in banana plantations with increasing years of organic fertilizer application.

Maintaining or improving soil chemical quality is critical for sustainable agricultural productivity and environmental safeguards. Organic fertilizer application, a common agricultural practice in banana cultivation, is often associated with greater microbial biomass and activity, which are linked to improvements in soil chemical quality. However, the effect of the duration of organic fertilizer application on soil chemical quality and whether it is microbially driven still needs to be investigated. We collected soil samples from banana plantations consistently applying organic fertilizers for 1 (Y1), 4 (Y4), 7 (Y7) and 10 (Y10) years. Soil chemical quality is expressed as total data set (TDS) and minimum data set (MDS) based on chemical indicators, and soil microorganisms are characterized by phospholipid fatty acid (PLFA). Based on TDS and MDS, the soil chemical quality indices in Y7 and Y10 treatments were significantly higher than that in Y1 and Y4 treatments. Soil total PLFA concentrations and the proportional abundance of fungi and arbuscular mycorrhizal fungi increased with prolonged banana cultivation. Total PLFA concentrations were significantly positive correlation with the soil chemical quality index. Soil gram-positive bacteria (G+), bacteria, protozoa and ratio of G+ to gram-negative bacteria (G-) were major drivers of soil chemical quality. The organic fertilizer application can significantly improve soil chemical quality, which is regulated by soil bacteria. Regular application of organic fertilizers is important in promoting soil quality and soil biological properties need to be incorporated into the assessment of soil health in banana plantations. © 2022 Society of Chemical Industry.

Effects of pesticides on reproductive parameters in hoplobatrachus occipitalis (günther, 1858), an edible frog living in the drainage furrows of a banana plantation in the locality of dabou

Sexual maturity size, gonado-somatic index, sex ratio and fecundity were studied during four seasons, from January to December 2020, in Hoplobatrachus occipitalis which lives in the water of drainage furrows of banana plantations treated with phytosanitary products in the locality of Dabou. Our results reveal that the sizes of first sexual maturity in females and […]

What the Chlordecone Pollution Says About Modes of Inhabiting the World: Examining the Intersection of Socio-Racial Inequality and Environmental Degradation in Tropiques Toxiques by Jessica Oublié et al.

In Tropiques Toxiques (2020), Jessica Oublié et al. use the graphic novel as a medium to convey the stories of people in the departments of France, in particular Guadeloupe and Martinique, whose lives have been affected by chlordecone, a toxic pesticide used in banana plantations between the years 1972 and 1993. The intimate dive into people’s lived experiences in the French Caribbean is paired with the elaboration of attentive scientific knowledge around the contamination caused by chlordecone and its continued effects. While the substance was already under scrutiny for its toxic effects on human and wildlife in the 1970s in the US, successive governments in France allowed the use of chlordecone to sustain and intensify the production of bananas against international competitors, until it was officially banned in 1993. As a point of departure, this article argues that such human-made ecological disaster forefronts the intersection of socio-racial inequality and environmental degradation, while questioning the practice of nonknowledge on the issue of chlordecone poisoning. How, then, does the graphic novel break the cycle of ignorance and call attention to socio-racial disparities not just in accessible knowledge, but also in protection of French citizens? And finally, what can chlordecone contamination say about our modes of inhabiting the world and the importance of imagining alternatives?

NESTING OF THE GREATER YELLOW-HEADED VULTURE (CATHARTES MELAMBROTUS) IN EASTERN PERU

The Greater Yellow-headed Vulture (Cathartes melambrotus) is one of the less known cathartids (Cathartiformes, Cathartidae), especially in its reproductive biology, being the only species in the family that does not have nest description. Here I describe the discovery of one nest located in a cavity 55 m above the ground on a 70 m high x 130 m wide cliff at 1.230 masl. in the eastern rainforest of central Peru. The nest was found during late dry season (October 31, 2019), and contained a well-developed chick (50-60 days old) which was being fed by the parents. The habitat surrounding the nesting site presented thinned forests for shade of coffee crops, banana and citrus plantations and remnants of adult secondary forest in the streams.

Pyrimethanil and chlorpyrifos air concentrations and pregnant women's urinary metabolites in the Infants' Environmental Health Study (ISA), Costa Rica.

Only few studies have compared environmental pesticide air concentrations with specific urinary metabolites to evaluate pathways of exposure. Therefore, we compared pyrimethanil and chlorpyrifos concentrations in air with urinary 4-hydroxypyrimethanil (OHP, metabolite of pyrimethanil) and 3,5,6-trichloro-2-pyridinol (TCPy, metabolite of chlorpyrifos) among pregnant women from the Infant's Environmental Health Study (ISA) in Matina County, Costa Rica. During pregnancy, we obtained repeat urinary samples from 448 women enrolled in the ISA study. We extrapolated pyrimethanil and chlorpyrifos concentrations measured with passive air samplers (PAS) (n=48, from 12 schools), across space and time using a Bayesian spatiotemporal model. We subsequently compared these concentrationswith urinary OHP and TCPy in 915 samples from 448 women, usingseparatemixed models andconsidering several covariables. A 10% increase in air pyrimethanil (ng/m3) was associated with a 5.7% (95% confidence interval (CI 4.6, 6.8) increase in OHP (μg/L). Women living further from banana plantations had lower OHP: -0.7% (95% CI -1.2, -0.3) for each 10% increase in distance (meters) as well as women who ate rice and beans ≥15 times a week -23% (95% CI -38, -4). In addition, each 1ng/m3 increase in chlorpyrifos in air was associated with a 1.5% (95% CI 0.2, 2.8) increase in TCPy (μg/L), and women working in agriculture tended to have increased TCPy (21%, 95% CI -2, 49). The Bayesian spatiotemporal models were useful to estimate pyrimethanil and chlorpyrifos air concentrations across space and time. Our results suggest inhalation of pyrimethanil and chlorpyrifos is a pathway of environmental exposure. PAS seems a useful technique to monitor environmental current-use pesticide exposures. For future studies, we recommend increasing the number of locations of environmental air measurements, obtaining all air and urine measurements during the same month, and, ideally, including dermal exposure estimates as well.

Prioritizing farm management interventions to improve climate change adaptation and mitigation outcomes—a case study for banana plantations

Intervening into agricultural systems necessarily includes risks, uncertainties, and ultimately unknown outcomes. Decision analysis embraces uncertainty through an interdisciplinary approach that involves relevant stakeholders in evaluating complex decisions. We applied decision analysis approaches to prioritize 21 farm management interventions, which could be considered in certification schemes for banana production. We estimated their contribution to climate change adaptation and mitigation as well as ecological outcomes. We used a general model that estimated the impacts of each intervention on adaptation (benefits minus costs), mitigation (global warming potential), ecological parameters (e.g., biodiversity and water and soil quality), and farming aspects (e.g., yield, implementation costs and production risks). We used expert and documented knowledge and presented uncertainties in the form of 90% confidence intervals to feed the model and forecast the changes in system outcomes caused by each intervention compared to a baseline scenario without the measure. By iterating the model function 10,000 times, we obtained probability distributions for each of the outcomes and farm management interventions. Our results suggest that interventions associated with nutrient management (e.g., composting and nutrient management plan) positively affect climate change adaptation, mitigation, and ecological aspects. Measures with no direct yield benefits (e.g., plastic reduction) correlate negatively with adaptation but have positive impacts on ecology. Creating buffer zones and converting low-productivity farmland (incl. unused land) also have positive ecological and adaptation outcomes. Decision analysis can help in prioritizing farm management interventions, which may vary considerably in their relationship with the expected outcomes. Additional work may be required to elaborate a comprehensive assessment of the underlying aspects modulating the impacts of a given measure on the evaluated outcome. Our analysis provides insights on the most promising interventions for banana plantations and may help practitioners and researchers in focusing further studies.

Natural occurrence of Beauveria caledonica, pathogenicity to Cosmopolites sordidus and antifungal activity against Fusarium oxysporum f. sp. cubense

Entomopathogenic fungi can provide a set of ecological services, such as suppressing arthropod pests and plant pathogens. In this study, novel indigenous Beauveria caledonica (Bc) strains were isolated from naturally infected banana weevils (Cosmopolites sordidus) occurring in commercial banana plantations in Brazil. The prevalence of infection by Bc strains on field-caught C. sordidus ranged from 1.3% to 12.9%. Similar to the Beauveria bassiana strains tested, none of the Bc strains caused more than 50% weevil mortality at a concentration of 1 × 108 conidia ml-1 . Bc strain CMAA1810 caused the highest mortality in C. sordidus and had enhanced insecticidal activity when formulated with an emulsifiable oil. In paired co-culture assays, this same strain showed a significant growth-inhibitory effect on the causal agent of Fusarium banana wilt (Fusarium oxysporum f. sp. cubense, Foc) of twofold magnitude compared with the control. Cell-free crude filtrates derived from the red-pigmented culture broth of Bc (CMAA1810) strongly reduced Foc conidial viability, and this inhibitory activity was inversely related to the age of the Bc culture. Crude concentrated filtrates from 4-day-old cultures exhibited the strongest antifungal activity (13-fold) compared with untreated Foc conidia. The abundant compound identified in the crude filtrate of Bc was oosporein (1,4-dibenzoquinone) present at a concentration of 0.829 ± 0.018 mg g-1 dry matter, and the antifungal activity of the filtrate was demonstrated. These results indicated that Bc strains might have the potential to manage both C. sordidus and Foc, two of the major phytosanitary problems in banana crops worldwide. Further research under field conditions using suitable formulations of virulent Bc strains in combination with the metabolite oosporein is needed to evaluate their efficacy in the management of C. sordidus and Foc in banana plantations. © 2022 Society of Chemical Industry.

Development of Banana Peduncle Juice Extractor For Ethanol and Fiber Production

Banana (Musa acuminata C.) peduncle is a waste byproduct of commercial banana plantations in the Philippines. Several studies proved the potential of utilizing this agricultural waste as raw material to produce ethanol, and the practical applications of its high-quality fiber. However, mechanical juice extraction was found to limit production as machines used are intended for other commodities, which may not meet functionality requirements for optimum performance. To meet the need, a juice extractor was developed to extract juice from banana peduncle without rupturing its fiber structure for the purpose of ethanol production and fiber recovery. The machine employed a system of crushing rolls as extraction mechanism and was studied under the effects of roll rotational speed (50, 70, and 90 rpm) and crushing load (0.8, 1.2, and 1.6 kN). Optimum performance of the machine was obtained under the optimal setting, 71.4 rpm and 0.8 kN, which resulted to input capacity (307.24 kg/h), juice extraction rate (82.92 kg/h), juice recovery (26.08%), extraction losses (4.21%), extraction efficiency (18.46%), fuel consumption rate (0.391 L/h), fiber extraction rate (54.83 kg/h), and fiber recovery (42.29%). ANOVA reveals that higher roll rotational speed and lower crushing load increases input capacity, juice and fiber extraction rates, and fiber recovery. Lower roll rotational speed and higher crushing load increases juice recovery and extraction efficiency. Higher roll rotational speed increases extraction losses while higher crushing load increases fuel consumption rate. No significant effect was found on the °Brix of extracted juice and on the tensile strength of the fiber. Ethanol analysis showed that the fermented juice contains 10-11% ethanol v/v while fiber tests showed tensile strength values approximate to 300 MPa.

First Report of Fusarium oxysporum f. sp. cubense Tropical Race 4 Causing Fusarium Wilt in Cavendish Bananas in Peru.

Fusarium oxysporum f. sp. cubense Tropical Race 4 (Foc TR4), the causal agent of Fusarium wilt of banana (FWB), is currently the major threat to the banana industry worldwide (Dita et al. 2018). Restricted to South Asia for more than 20 years, Foc TR4 has spread in the last years to the Middle East, Mozambique, and Colombia (García-Bastidas et al. 2019; https://pestdisplace.org/embed/news/map/disease/11). The incursion of Foc TR4 in Colombia increased awareness and prevention efforts across Latin American and the Caribbean (LAC). However, new Foc TR4 outbreaks in LAC countries were considered a matter of time. In April 2021, banana (Musa spp., Cavendish, AAA) plants (30% of incidence) showing typical symptoms of FWB, such as leave yellowing, wilting and vascular discoloration were observed in one farm (about 1 ha) located in Querecotillo, Peru (4°43'54.84"S 80°33'45.00"W). Mycological analyses of samples (pseudostem strands) collected from 10 symptomatic plants were performed as described by Dita et al. (2010). These analyses revealed a continuous presence of fungal colonies identified as Fusarium oxysporum species complex. Molecular diagnostics targeting two different genome regions (Dita et al 2010; Li et al. 2013) identified nine of these isolates as Foc TR4. These results were further confirmed by qPCR analyses using the commercial Clear Detections TR4 kit. The genome of four single-spore isolates (PerS1, PerS2, PerS3 and PerS4) was sequenced using the Illumina platform (MiSeq Kit, 2x151 bp Paired-End). The strain PerS4 was also sequenced using Oxford Nanopore (FLOW-MIN111; R10.3 chemistry) as described by Lopez-Alvarez et al., (2020). The generated draft assembly yielded 533 contigs for a size of 47 Mbp (BioProject: PRJNA755905), which is comparable with sizes of previously reported Foc TR4 strains (Asai et al. 2019; García-Bastidas et al. 2019; Maymon et al. 2020; Warmington et al. 2019; Zheng et al. 2018). The sequence assembly showed high contiguity (94.9%) and high similarity (95.48%) with the high-quality genome sequence of the Foc TR4 isolate 'UK0001' (Warmington et al. 2019). Further analyses to identify the presence/absence of full sequences for the putative effector genes (Secreted In Xylem - SIX) and their allelic copies, also revealed that the SIX genes profile of the strains isolated from Querecotillo matched with previously reported Foc TR4 isolates (Czislowski et al. 2017). Pathogenicity tests with three isolates and water controls were performed as described by Dita et al. (2010), using five Cavendish plantlets per treatment. Four weeks after the inoculation typical external and internal symptoms of FWB were observed only in the inoculated plants. Fungal isolates recovered from inoculated plants tested positive for Foc TR4 when analyzed with PCR diagnostics as mentioned above. No fungal isolates were recovered from water-control plants which did not show any symptoms. Altogether, our results confirm the first incursion of Foc TR4 in Peru. Currently, Foc TR4 has the phytosanitary status of a present pest with restricted distribution in Peru and it is under official control of the National Plant Protection Organization - SENASA. Reinforced prevention and quarantine measures, disease monitoring and capacity building to detect, contain and manage eventual new outbreaks of Foc TR4 are strongly encouraged across LAC banana producing countries, especially for those bordering Peru with larger banana plantations, such as Ecuador and Brazil.

Comprehensive evaluation of throughfall erosion in the banana plantation

AbstractBanana is an important cash crop in tropical and subtropical areas; however, the development of banana farming has caused thorny ecological problems, such as water and soil loss. There are few studies on the runoff response to rainfall in banana land to date. In this study, several evaluation indexes, rainfall redistribution, throughfall erosivity, splash kinetic energy, soil splash loss and runoff, respectively, were used to clarify the mechanism of soil erosion in banana land. Results showed that the atmospheric rainfall was significantly redistributed by the banana canopy, with about 81.2% throughfall, 8.3% stemflow and the rest canopy interception. Although the throughfall erosivity evaluated by the model was slightly lower than that of open rainfall, the throughfall kinetic energy and the soil particle splash loss reached 1.5 times and 5 times higher than that of open rainfall, respectively. Consequently, throughfall has an obvious splash erosion effect on the surface soil. In addition, influenced by throughfall and stemflow, surface runoff during the rainy season (May–September) accounts for the annual 91.7%, July and August in particular having the highest incidence of soil erosion in banana land. The above results suggest that the convergence effect of the banana canopy on rainwater is the main inducement for the increase in throughfall volume and surface runoff volume. Therefore, it is necessary to implement soil and water conservation measures on banana fields during the rainy season, such as planting low vegetation under the banana canopy to mitigate splash effects.

Pengaruh Umur Kematian Tanaman Sumber Inokulum Banana Bunchy Top Virus Terhadap Efisiensi Penularannya

BBTV is one of the important diseases in banana plants, the transmission of BBTV can be carried out by Pentalonia nigronervosa . In some banana plantations infected plants are usually cut down because they are considered unable to produce optimal production. The felled plants will then be placed around healthy plantations, this situation is thought to have the potential as a place for P. nigronervosa to temporarily live and spread the virus to other healthy plants. This study aims to determine the ability of dead plants that host P. nigronervosa to re-transmit the virus to healthy plants. The study was conducted using a Randomized Block Design (RAK) with six treatments on the day of death of infected plants, namely, 0, 5, 10, 15, 20, and 25 days, with five replications. From the results of the study, it was found that plants infected by BBTV still had potential to transmit the virus to healthy plants through the P. nigronervosa . Transmission of BBTV from dead plants on the fifth day resulted in the highest average of BBTV infection. The incubation period of virus in plants ranged from 30-53 days after inoculation. From this research, it is hoped that farmers will pay more attention to thoroughly eradicate banana plants infected by BBTV, removed all plant and suckers thoroughly together with their corms.

First Report of Dickeya fangzhongdai Causing Peduncle Soft Rot of Banana in China.

Banana (Musa spp.) is a popular fruit all over the world, and it's also an important cash crop with a planting area of 358,924 ha in southern China. In July 2020, a peduncle soft rot disease occurred on dwarf banana (Musa sp. cv. Guangfen) in Guigang city (N22°50'29″, E109° 43'34″), Guangxi province, China. More than 20% plants were infected in the banana plantation. The first external sign of the disease appeared on the incisional wound after the flower bud was cut off from the peduncle. The symptom initially appeared as a black lesion on the wound, then extended into the internal tissue of the whole peduncle. In the later stages, the internal tissue became soft and rot, occasionally formed a necrotic cavity, and eventually led to the black rot of the whole peduncle with a foul smell. To isolate the pathogen, the internal lesion tissues of 5 mm × 5 mm were collected between the border of symptomatic and healthy tissue, treated with 75% ethanol for 10 s, and 0.1% HgCl2 for 3 min, then rinsed with sterile water for three times. Sterilized tissue fragments were cut to pieces with sterilized surgical shears and soaked in 5 mL sterile water, then shaken for 10 min in a vortex oscillator. The suspension was diluted 1000 times with sterilized water，then plated on nutrient-agar medium and incubated at 28℃ in darkness for 24 h. Among the 32 isolates, 23 pure bacterial cultures with similar morphology were predominantly obtained from the samples. These bacteria were gram-negative, and their colonies were initially yellowish white with irregular edges and smooth surfaces, then turned to grayish blue after 72 h incubated at 28℃. The representative isolates GZF2-2 and GZF1-8 were selected for further identification. Genomic DNA was isolated from the bacteria and the 16S rDNA was amplified with primers 27F/1492R (Weisburg et al. 1991) and sequenced. The obtained sequences (GenBank Accession No. MZ768922 and OK668082) showed >99% identities to several records of Dickeya fangzhongdai deposited in NCBI GenBank (1400/1404 bps for GZF2-2 to KT992690, 1409/1417 bps for GZF1-8 to MT613398) based on BLAST analysis. In addition, the recA, fusA, gapA, purA, rplB, dnaX genes and the 16S-23S intergenic spacer (IGS) regions of the two isolates were also amplified and sequenced (GenBank Accession Nos. OK634381-OK634382, OK634369- OK634370, OK634373-OK634374, OK634377-OK634378, OK634385-OK634386, OK634365- OK634366 and OK631722-OK631723) as described by Tian et al. (2016). All the DNA sequences matched that of D. fangzhongdai strains JS5T (percent identities>99.06%), PA1 and ECM-1 in GenBank. Neighbor-joining phylogenetic analysis by software MegaX (Kumar et al. 2018) based on the 16S rDNA sequences revealed that the two isolates were in the same clade with reported D. fangzhongdai strains. Multilocus sequence analysis of the other seven regions also showed the two representative isolates were belong to D. fangzhongdai. Therefore, the isolates were identified as D. fangzhongdai. Pathogenicity of isolate GZF2-2 was investigated to demonstrate Koch's postulate. The end of the banana peduncles of 6 healthy plants were cut off, and 10 mL bacterial suspension (108 CFU/mL) was inoculated to the fresh wound on the plants using sterile brushes. Six control plants were inoculated with sterilized water. All the inoculated peduncles were covered with plastic bags to maintain high humidity. After 28 days, all the peduncles inoculated with strain GZF2-2 showed soft rot symptoms similar to those observed in the field, while the controls remained symptomless. The same bacteria were re-isolated from the symptomatic peduncles and confirmed by sequencing the 16S rDNA. D. fangzhongdai has been reported to cause soft rot on onion (Ma et al. 2020) and bleeding cankers on pear trees (Chen et al. 2020). To the best of our knowledge, this is the first report of D. fangzhongdai causing peduncle soft rot on banana in China.

A soil quality physical-chemical approach 30years after land-use change from forest to banana plantation.

Bananas are a worldwide cultivated crop and one of the main agricultural activities in Brazil. The banana orchards cultivated in the region of São Paulo State are under native areas of the Atlantic Forest biome. The Atlantic Forest has suffered agricultural and urban pressure for many years. Banana crops require soil management and superficial vegetation removal in the first cycles. We conducted a study aiming to understand the impact of long-standing banana cultivation in the Atlantic forest region. Soil samples in banana plantations (EBP) and forest remnants (FR) were collected from trenches with 0- to 100-cm layers. The soil bulk density in EBP until 30-cm depth was 12.76% higher than that in FR. Quantifications of macropores and micropores in FR reached values higher than those in EBP. The results showed that carbon stocks decreased from the top to the deeper layers. Thirty years after the conversion, the FR treatment accumulated 28.23% more carbon than EBP. Considering our results, it was evident that changes in physical and chemical properties reflected the negative impacts of the banana plantations, cropped through conventional management, when converted from forest even in regard to a remnant one. These findings, showed for the first time, lead us to understand the soil management of banana plantations, following conventional agriculture systems, as a potential carbon stock reducer and a factor resulting in the loss of soil quality in the region. Additionally, our data can be used by environmentalists and government policymakers to promote environmental sustainability.

Biological Control Options for the Golden Twin-Spot Moth, Chrysodeixis chalcites (Esper) (Lepidoptera: Noctuidae) in Banana Crops of the Canary Islands.

Simple SummaryThe golden twin-spot moth, Chrysodeixis chalcites, is a pest whose larvae cause serious skin injuries to banana fruits in the Canary Islands, reducing their commercial value. The use of Integrated Pest Management (IPM) strategies (cultural, biological, and chemical control) is recommended for the effective and sustainable management of this pest. The identification of its parasitoids and the quantification of their effects on pest populations are essential for the development of biological controls. In this study, we conducted an extensive survey to identify the most important parasitoid species of Ch. chalcites and evaluated the efficacy of the egg parasitoid Trichogramma achaeae as a biological control agent in banana plantations in the Canary Islands. Our findings indicate that populations of native parasitoids can exert a certain degree of natural control over Ch. chalcites. However, their naturally occurring populations are insufficient to minimize the damage caused by this pest. Thus, the development of IPM programs based on the use of selective insecticides, the conservation of natural enemies and inundative releases of mass-reared wasps is also necessary. The parasitoid T. achaeae has been identified as a promising biological control agent of Ch. chalcites in greenhouse banana crops, but it is necessary to carry out further studies to establish the most appropriate release strategies.Chrysodeixis chalcites (Esper) (Lepidoptera: Noctuidae) is a significant pest in banana plantations in the Canary Islands. Field surveys were carried out to identify its naturally occurring parasitoids and estimate their parasitism rates between September 2007 and October 2010. Ch. chalcites was parasitized by six different larval/pupal parasitoid species: Cotesia sp., C. glomerata L. (Hym.: Braconidae), Aplomyia confinis Fallén (Dip.: Tachinidae), Hyposoter rufiventris Perez, Ctenochares bicolorus L. (Hym.: Ichneumonidae) and Aleiodes sp. (Hym.: Braconidae). Among them, Cotesia sp. was the most frequent species, accounting for 8.18% of parasitized larvae. High levels of egg parasitism were detected, with Trichogramma achaeae Nagaraja and Nagarkatti (Hym.: Trichogrammatidae) being the most widely distributed egg parasitoid. A greenhouse assay was also carried out on a commercial banana crop with the aim of evaluating the potential of T. achaeae as a biological control agent and compared with a chemical control. Five periodic inundative releases of 35 adults/m2 every 21 days were necessary to achieve an adequate parasitism level (56.25 ± 1.61%). Moreover, there was 15.75% less foliar damage in the biological control plot compared to the chemical control plot. These results indicate that T. achaeae could be a promising biocontrol agent of Ch. chalcites in greenhouse banana crops.

Banana growing and its climate suitability in the municipality of Recife-Pe, Brazil

The banana tree is a plant characteristic of the tropical region, demanding in temperatures and rainfall with good regional distribution, due to its low cost and high nutritional value, it is an integral part of the diet of populations. The objective is to analyze the climatic oscillations, from the calculation of the water balance and its climatic classification, according to the methods of Thorn Thwaite and Köppen, for the city of Recife, verifying the occurrence of the aptitude of the banana cultivar. The average rainfall and temperature data were acquired from the National Institute of Meteorology, for the period between 1962 and 2016. Banana plantations are moderate because they have a water deficit of 287.4 mm. The evaporative power registered in the municipal area is high, but the demand for irrigation complements the scarcity of water to cultivate it. The local altitude is in the range of planting of the cultivar as well as the variability of the relative humidity of the air. Wind is one of the limiting factors for commercial exploitation of banana cultivation, if the cultivars are tall and planted in sandy soils.

Relationships between land use, habitat quality, physicochemical water quality and fish communities in the Sironko River Catchment, a mountainous tropical stream flowing into the Lake Kyoga in Eastern Uganda

AbstractThis study investigated the relationships between land use, habitat quality, physicochemical water quality and fish assemblage in the Sironko River catchment, a tropical mountain stream flowing into the Lake Kyoga asin in Eastern Uganda. The study was carried out at different land use sampling sites (natural forest, pastureland, plantation forest, mixed agriculture, banana plantation, urban and sugarcane plantation) for 6 months from November 2019 to April 2020. The habitat quality score (HQS) ranged between 49% in the urban area and 75% in the natural forest. There was a general increase in the temperature, conductivity, total dissolved solids, turbidity and nitrate concentration in the Sironko River as it flowed from upstream to downstream from the natural forest to the sugarcane plantation. Conversely, there was a reduced dissolved oxygen concentration and water transparency as the river traversed the different land uses downstream. A total of 765 fish individuals belonging to 9 fish species (Amphilius jacksonii, Amphilius uranoscopus, Barbus altianalis, Labeo victorianus, Clarias leocephalus, Clarias carsonii, Cyprinus carpio, Barbus palludinosus and Barbus jacksonii) were captured using an electrofishing gear. Fish identification was based on external morphological characteristics. Amphilius uranoscopus and Barbus altianalis were only caught in the natural forest and pastureland at a high altitude characterized by low temperature and high dissolved oxygen concentration. The fish species belonged to 3 trophic feeding groups dominated by the insectivorous fish. Pearson correlation coefficients showed a weak negative relationship (r = −0.249) between fish community and habitat quality, while fish assemblage and physicochemical water quality unveiled a weak positive relationship (r = 0.176). The coefficient of determination (R2 = 0.695) indicated 69.5% of the fish community variability was accounted for by the physicochemical water quality variables in Sironko River System. Accordingly, it was concluded that physicochemical water quality attributes are the most important factors determining the distribution of fish species with land use in the Sironko River catchment, a tropical mountain stream. The Sironko River catchment is hydraulically and biologically connected to Lake Kyoga through a series of satellite lakes and swamps. The river is spawning area for Clarias leocephalus, Clarias carsonii and Amphilius lujani fish species of the lake.

CO2, CH4 and N2O emissions after fertilizer application in banana plantations located in the Brazilian Atlantic Forest

AbstractBananas are important tropical fruits conventionally cultivated under intensive nitrogen fertilization. A current challenge is to understand the environmental impacts of this crop across the different cultivation stages considering greenhouse gas emissions. Therefore, the present study evaluated whether inorganic fertilization with ammonium sulphate and urea during different planting stages can change soil CO2, CH4 and N2O emissions. The experiment was conducted in 2018 in an Atlantic Forest region of São Paulo State, Brazil. We used the chamber‐based methodology for gas sampling in young and established banana plantations and in a forest remnant fragment. Seasonal differences in temperature and rainfall during the sampling period resulted in a larger WFPS during the wet season. The CO2 emissions followed the rainfall variations. CH4 fluxes were mainly resulted of methanotrophy reactions. The maximum and minimum N2O fluxes were 7.38 and −0.93 mg m2 day−1, peaking after nitrogen fertilization. We found that the accumulated N2O fluxes from soil were greater for the two banana plantations than those observed in the forest remnant in dry and wet seasons. The highest N2O peaks were observed in the young banana plantation. CH4 uptake was 92 and 61% less in young and established banana plantations than in the forest remnant, while N2O emissions were 95 and 74% greater in young and established banana plantations than in the forest remnant. Considering the negative effect of N2O emissions, reduced rates of nitrogen application and the adoption of conservation practices should be considered in young banana plantations.

Chlordecone in basal trunk wood of native trees growing in abandoned banana plantations in Guadeloupe, France

Chlordecone (CLD), used to control the Cosmopolites sordidus banana weevil and released from polluted banana plantations, continues to contaminate ecosystems in the French Caribbean. Edible plants have been actively studied for risk prevention, but trees have not, even though they could play a significant role in future remediation strategies. CLD contents were analysed in 24 pioneer trees belonging to 13 species found in abandoned banana plantations in Guadeloupe, at three contaminated sites on Nitisols (Site 1) and Andosols (Sites 2 and 3). Wood samples were taken from each tree in the basal part of the trunk and the soil at its foot and their CLD content was measured by the analytical laboratory for the Drôme département (26) in Valence, France. Mean CLD contents in the top 30-centimetre soil layer from sites 1, 2 and 3 were 2,543 ± 702, 5,251 ± 1,102 and 875 ± 865 µg/kg dry soil respectively. Of the trees, 96% were contaminated. The CLD content in trees growing on Nitisols (3,406 ± 1,658 µg/kg dry wood) was at least 5 times higher than in trees growing on Andosols (299 ± 314 and 226 ± 378 µg/kg), but no clear relationships were found with soil CLD contents. Calculations of available CLD dissolved in the soil liquid phase using equations and soil datasets in the literature showed higher available CLD contents in Nitisols than in Andosols and a linear relationship between CLD available in soil and concentrations of CLD in wood, regardless of the type of soil. Trees growing on Nitisols are the plants most highly contaminated by CLD of all the plants in which this compound has been studied so far. With a plant-to-soil bioconcentration ratio around 150 l/kg, the consistent CLD uptake efficiency of the trees needs to be taken into account in further research for CLD remediation.

The Feeding Landscape: Bird and Human Use of Food Resources across a Biocultural Landscape of the Colombian Andes

Agriculture impacts both human welfare and biodiversity at the same time. Still, social and ecological assessments have commonly analyzed the relevance of agroecosystems separately. We evaluated the human and avian feeding use of the biocultural landscape in Jardín, Colombia, using a socioecological approach. Together with farmers, we identified the main socioecological units of the landscape (i.e., fincas, grazing lands, town, forests) and determined the use of each unit in terms of food foraging from forests, crop cultivation, cattle grazing, food commercialization, and food industrialization. We compared the richness of the food resources produced among finca sections (i.e., gardens, coffee–banana plantations, grazing lands). Then, we surveyed avian behavior to contrast the richness of bird species, feeding use and intensity, and food types consumed by birds among the units. Fincas were shown to play a pivotal role in feeding both humans and birds. Gardens provide food for people as well as nectarivore and frugivore birds. Coffee–banana plantations are economically relevant, but their food provision is limited and could be enhanced by increasing the diversity of the food crops within them. The town supports commerce and granivorous birds, whereas grazing lands have limited feeding importance. Forests are used by birds to capture invertebrates but do not supply much food for the people. Our approach fosters the identification of key socioecological units, demonstrating that studying both humans and wildlife enhances the comprehension of biocultural landscapes.