Crown Rot Disease Research Articles

Deoxynivalenol Detoxification in Transgenic Wheat Confers Resistance to Fusarium Head Blight and Crown Rot Diseases.

Fusarium diseases, including Fusarium head blight (FHB) and Fusarium crown rot (FCR), reduce crop yield and grain quality and are major agricultural problems worldwide. These diseases also affect food safety through fungal production of hazardous mycotoxins. Among these, deoxynivalenol (DON) acts as a virulence factor during pathogenesis on wheat. The principal mechanism underlying plant tolerance to DON is glycosylation by specific uridine diphosphate-dependent glucosyltransferases (UGTs), through which DON-3-β-d-glucoside (D3G) is produced. In this work, we tested whether DON detoxification by UGT could confer to wheat a broad-spectrum resistance against Fusarium graminearum and F. culmorum. These widespread Fusarium species affect different plant organs and developmental stages in the course of FHB and FCR. To assess DON-detoxification potential, we produced transgenic durum wheat plants constitutively expressing the barley HvUGT13248 and bread wheat plants expressing the same transgene in flower tissues. When challenged with F. graminearum, FHB symptoms were reduced in both types of transgenic plants, particularly during early to mid-infection stages of the infection progress. The transgenic durum wheat displayed much greater DON-to-D3G conversion ability and a considerable decrease of total DON+D3G content in flour extracts. The transgenic bread wheat exhibited a UGT dose-dependent efficacy of DON detoxification. In addition, we showed, for the first time, that DON detoxification limits FCR caused by F. culmorum. FCR symptoms were reduced throughout the experiment by nearly 50% in seedlings of transgenic plants constitutively expressing HvUGT13248. Our results demonstrate that limiting the effect of the virulence factor DON via in planta glycosylation restrains FHB and FCR development. Therefore, ability for DON detoxification can be a trait of interest for wheat breeding targeting FHB and FCR resistance.

The effect of chemical and biological treatment on root and crown rot disease caused by Phytophthora cryptogea Pethybr. & Lafferty in Gerbera

AbstractPhytophthora root and crown rot (Phytophthora cryptogea) on gerbera is difficult to manage because most gerbera cultivars are susceptible to P. cryptogea. This study was conducted in order to determine the in vivo (pot experiment) efficacy of some fungicides and biofungicides. In pot experiments, fungicides were applied 7 days after inoculation with P. cryptogea, while biofungicide was applied 7 days before inoculation. In this study, soil drenches of five fungicides were tested. “Ametoctradin+dimethomorph (100 ml/day),” “mandipropamid+difenoconazole (60 ml/day),” “propamocarb+fosetyl‐Al (200 ml/day),” “mancozeb+metalaxyl‐M (250 g/day)” and “azoxystrobin+difenoconazole (100 ml/day)” active substances were used. Similarly, one biofungicide Bacillus amyloliquefaciens syn. MBI 600 (50 g/100 L) was applied by soil drenching. Efficacy of treatments was assessed according to the percentage of the root system which was visibly rotten at the end of the experiment. Root and crown rot severity was rated on a scale of 0 = 0% root system necrotic, 1 = 1%‐25% necrotic, 2 = 26%‐50% necrotic, 3 = 51%‐75% necrotic and 4 = 76%‐100% necrotic from 12 to 21 days. In this experiment, “azoxystrobin 200 g/L + difenoconazole 125 g/L” exhibited the highest efficacy against P. cryptogea with a ratio of 43.75%. The other fungicides and biofungicides ametoctradin 300 g/L + dimethomorph 225 g/L, mandipropamid 250 g/L + difenoconazole 250 g/L, propamocarb 530 g/L + fosety‐Al 310 g/L, mancozeb 64%+metalaxyl‐M 4% and Bacillus amyloliquefaciens syn. MBI 600 11% were ineffective. Importance should be given to management strategies of P. cryptogea of and more experiments should be carried out for a better understanding of the use of registered fungicides and biofungicides.

First Report of Crown and Root Rot Disease Caused by Phytophthora cryptogea on Gerbera in Izmir Province in Turkey

First Report of Crown and Root Rot Disease Caused by <i>Phytophthora cryptogea</i> on Gerbera in Izmir Province in Turkey

Trichoderma dan Gliocladium untuk Mengendalikan Penyakit Busuk Akar Fusarium pada Bibit Kelapa Sawit

Trichoderma and Gliocladium for Controling Fusarium Root Rot Disease of Oil Palm SeedlingsFusarium spp. have been reported as the causal agent of common spear rot and crown rot diseases on oil palm. An effective strategy to control these diseases is not available yet. This research was aimed to find biocontrol agents for effective control of crown rot disease on oil palm seedlings caused by Fusarium spp. The experiment consisted of 3 parts i.e. pathogenicity test of 3 isolates of Fusarium, identification and in vitro test of biocontrol agents, and in planta test of biocontrol agents against Fusarium spp. In vitro test was done through dual culture test and test for volatile compound produced by the biocontrol agents. In planta test was conducted through inoculation of Fusarium spp. into oil palm seedlings growing on medium containing selected biocontrol agents i.e. Trichoderma harzianum, T. virens, T. inhamatum, and Gliocladium fimbriatum. In vitro test showed that Gliocladium fimbriatum 1 and 2 were inhibited effectively the growth of Fusarium spp. on the dual culture test, whereas T. harzianum Gadingrejo 2 was inhibited effectively the growth of Fusarium spp. on volatile compound test. The application of biocontrol agents was effective to protect oil palm seedlings from Fusarium spp. infection.

First Report of Fusarium Wilt Caused by Fusarium oxysporum on Strawberry in Bangladesh

Strawberry (Fragaria × ananassa) is a newly introduced small fruit crop in Bangladesh, which has gained considerable interest from both growers and consumers. Increasing incidence of wilt and crown rot diseases is a challenge for strawberry growers. In March 2016, wilted foliage and dead strawberry plants of cv. Strawberry Festival were found in a strawberry nursery in Rajshahi district of Bangladesh affecting 10% of the plants. Symptoms included wilting of foliage, drying and withering of older leaves, stunted growth, and reduced fruit production, leading to eventual plant collapse. A lengthwise cut through the crown of diseased plants showed distinct brown to reddish discoloration similar to that described by Koike et al. (2009). The crowns were surface sterilized in 2% NaOCl for 1 min followed by 70% ethanol for 5 min. Small pieces (2 × 2 mm) of the internal discolored tissue were placed on half-strength potato dextrose agar (PDA) medium and incubated for 7 days at 25°C. Single-spore isolates (BRSP-02 and BRSP-12) were obtained and plated to PDA, cornmeal agar, and V8 juice agar. Isolates had a growth rate 0.8 cm/day on PDA medium and produced sporodochia with septate macroconidia. Colonies also produced single-celled microconidia from unbranched, short, monophialidic conidiophores on PDA consistent with Fusarium oxysporum (Nelson et al. 1983). The internal transcribed spacer (ITS1, 5.8S rRNA, and ITS2), actin (ACT), and translation elongation factor 1-alpha (EF-1α) of the isolates were amplified using primers ITS-1/ITS-4, ACT-512F/ACT-783R, and EF1-728F/EF1-986R, respectively (Carbone and Khon 1999; White et al. 1990). ITS sequences of the isolates BRSP-02 and BRSP-12 (GenBank accession nos. LC383470 and LC383471, respectively) showed 99% similarity with the sequence from F. oxysporum strain SHBV2 (KY090783). Sequence identity for EF-1α (GenBank accession nos. LC383472 and LC383473, respectively) was 98 to 99% with the sequence from F. oxysporum isolate BRIP59170 (KX434915). The ACT sequences (GenBank accession nos. LC383784 and LC383785, respectively) showed 97 to 98% similarity with the sequence from F. oxysporum isolate C-11 (KY798318). Based on the aligned sequences of ITS and EF-1α, molecular phylogenetic analysis by the maximum likelihood method and maximum parsimony method, the isolates (BRSP-02 and BRSP-12) were named as F. oxysporum. The isolates are archived in the Department of Biotechnology at Bangabandhu Sheikh Mujibur Rahman Agricultural University in Bangladesh on dried filter paper at 4°C and are available on request. To confirm the pathogenicity of the fungus, five 3-month-old tissue-cultured ‘Strawberry Festival’ plants were inoculated by dipping the roots into either 400 ml of conidial suspension (with 5 × 10⁶ conidia/ml) of the isolate BRSP-12 or into sterile distilled water (control) for 15 min. The inoculated plants were transplanted into plastic pots with artificial peat-based soil mix and maintained in the greenhouse with a high daytime temperature of 25°C and low nighttime temperature of 20°C. After 3 weeks, all plants inoculated with isolate BRSP-12 were stunted and developed wilt symptoms similar to those observed in the field, whereas the control plants remained healthy. Plants were then dug out, and crowns were cut longitudinally to check for internal discoloration. Light orange discoloration of crown tissues was observed in inoculated plants, but all the control plants remained symptomless. The fungus was successfully reisolated on half-strength PDA medium from 100% of crowns and had morphology as characterized before, fulfilling Koch’s postulates. To the best of our knowledge, this is the first report of Fusarium wilt of strawberry in Bangladesh. This disease has been reported from a number of other countries including Argentina, Australia, China, South Korea, Spain, the United States, and Japan (Koike et al. 2009; Williamson et al. 2012).

Antifungal Activity of Nanochitin Whisker against Crown Rot Diseases of Wheat.

Nanochitin whisker (NC) is a rodlike particle with a cationic nature and high biological activities. Crown rot, caused by soil-borne fungal pathogens including Fusarium pseudograminearum( Fp) and Fusarium graminearum( Fg), is one of the most damaging diseases in wheat. To explore the antifungal activity of NC against wheat diseases, the effects of nanochitin whisker suspension (NCs) on fungal growth and conidial production of Fp and Fg were studied in vitro. NCs and its mixture with chemical fungicide as a seeds coating agent for crown rot disease control were also investigated using Fp as a model microorganism in a pot test. The results showed that NCs had significant inhibitory effects on mycelial growth and conidial production of Fp and Fg at concentrations of 30 and 300 ppm in the growth medium. Particularly, 300 ppm of NCs was capable of reducing conidial formation 89.25% and 82.28% for Fp and Fg, respectively. When seeds were treated with a mixture of NCs and tebuconazole, the disease control efficiencies increased to 79.30% and 90.02% for NCs at concentrations of 10 and 30 ppm, respectively. Greener and shorter seedlings were also observed in the pot experiment. This indicates that NCs have strong antifungal activity against the soil-borne pathogens of wheat and reduce use of chemical fungicide in wheat plantation.

Post-harvest shelf-life of banana and guava: Mechanisms of common degradation problems and emerging counteracting strategies

Banana and guava have short shelf-life at tropical ambient temperature due to climacteric ripening associated changes like rapid softening, senescence spotting, off-odor development, anthracnose, and crown rot disease incidence, and chilling injury occurrence during storage below 13 °C. Commercially post-harvest treatment involved submerging banana and guava in solutions of benomyl or thiabendazole or imazalil. These chemicals are harmful to human health and the environment. Moreover, the fungal pathogens have developed resistance to these fungicides. Hence search of alternative non-chemical, health and environment friendly strategies are major focus of the researchers over the world. Treatment with organic acids, plant extract having antimicrobial properties prevented diseases either by direct action on the fungus or by inducing defense response by increasing the activity of antioxidant enzymes like superoxide dismutase, lipoxygenase, catalase. Degradation of plant parts occurs due to accumulation of reactive oxygen species and enzymatic oxidation of polyphenols during senescence, chilling stress, low oxygen, or high carbon dioxide injury. The deteriorations are evaluated by physical parameters like color change, accumulation of superoxide anion, hydrogen peroxide, malondialdehyde byproducts, accumulation of thiobarbituric reactive compound and ion leakage percentage. The selection of application concentration and treatment duration of 1-methylcyclopropane (1-MCP) treatment which act as an ethylene inhibitor is critical in extending shelf-life of banana and guava. The modified atmosphere, controlled atmosphere storage and edible coating reduced time to occurrence and intensity of climacteric peak respiration, slowed down ripening associated changes, prevented accumulation of reactive oxygen species (ROS) thereby extended shelf-life of guava and banana.

Management of Crown and Root Rot Diseases in Strawberry Commercial Fields in Egypt

Surveyed strawberry fields at three different districts (Abo Swar, EL-Kassasin and El-Manayef) in Ismailia Governorate during 2014 -2016 growing seasons showed that 13 fungal species belonging to 13 genera were isolated from infected roots, runners and crowns segments of strawberry plants. The most frequent isolated fungi were; Macrophomina phaseolina (53.33%) and Colletotrichum acutatum (33.33%). These two pathogenic fungi were used in this study. Biological and chemical control experiments were conducted and significant differences in diseases incidence (DI%) and disease severity (DS%) were found among treatments of bioagents and chemical fungicides compared with control treatments. DI and DS percentages reached 0% when Bacillus subtilis or Rizolex were applied in plots of artificial infested soil with M. phaseolina and C. acutatum. Trichoderma harzianum occupied the second rank after B. subtilis, Rizolex (15 and 7.4% for DI) for M. phaseolina , (10 and 6.5% for DS)for C. acutatum, T. viride (16 and 16% for DI), (26 and 11% for DS) and Streptomyces canescens (20 and 21% for DI), (25 and 26% for DS), respectively. Moreover; Rizolex gave best results in pathogens control more than Topsin-M fungicide. In field experiment; the effect of soil disinfection using three treatments; two fumigants (Methyl bromide and Agrocelhone) and solar heating solarization applied on two strawberry cultivars (Festival and N-70) during 2015 and 2016 seasons were studied. Soil fumigation with Agrocelhone™ compound and Methyl bromide (MB) led to the best results for soil disinfection on both Festival and N70Strawberry cultivars during two seasons. Percentage DI and DS of crown and root rot diseases occurred were (9.4, 9.0%) and (8.4, 7.5%) for both cultivars, respectively in 2015 it was very low (2.9, 3.0%) and (2.5 and 3.0%); respectively when applied again in 2016.

Survey and Characterization of Strawberry Cultivars Susceptibility to Crown and Root Rot Diseases in Ismailia Governorate, Egypt

Survey and Characterization of Strawberry Cultivars Susceptibility to Crown and Root Rot Diseases in Ismailia Governorate, Egypt

EFFICACY OF SACCHAROMYCES CEREVISIAE TO CONTROL CROWN ROT OF BANANA CAUSED BY FUSARIUM SEMITECTUM

Crown rot disease of Banana is adversely affecting the quantity and quality of the fruits for consumption and utilization. The bananas collected from the local markets of Hyderabad, Tando Allahyar and Quetta were found suffered with different types of rots such as crown rot, anthracnose, fruit rot and stem end rot. Among them crown rot of banana was found predominantly followed by anthracnose and other fruit rots. Incidence and severity varied with the markets and locations. Fusarium semitectum found predominately associated with the affected fruits showing crown rot symptoms. So yeast (Saccharomyces cerevisiae) were evaluated against F. semitectum under in-vitro conditions. S. cerevisiae also tested against crown rot disease development of banana fruit inoculated with F. semitectum. The addition of Saccharomyces cerevisiae in the culture medium has brought 93% reduction in the growth of F. semitectum. yeast were also tested against crown rot disease development on banana fruits by direct contact method. Yeast treatment brought more than 40% reduction in crown rot disease development as compared to the untreated fruits. The present study indicates that active yeast have the potential to manage harmful plant pathogens and thus could provide an alternate, reliable and eco-friendly control of crown rot disease.

Thiophanate methyl susceptibility and alterations in tri5, Mgv1 and StuA expression among Fusarium graminearum and F. culmorum isolates

Fusarium graminearum and F. culmorum are phytopathogenic species that cause head blight and crown rot diseases in cereals worldwide. These two phytopathogenic fungi show great variation in terms of phenotypic, biochemical and genetic characteristics. In this study, linear growth rate, thiophanate methyl (TPM) resistance, survival and toxin production- associated gene expressions, and beta-tubulin nucleotide sequence knowledge of F. graminearum from Turkey and Iran and F. culmorum isolates from Turkey were investigated. The mean linear growth rate values of isolates ranged from 7.58 to 15.16 mm/day. In TPM resistance analysis, each isolate was characterized as highly sensitive to TPM, with IC50 values between 2 and 4 μg/ml TPM. TPM-subjected isolates showed decreased tri5 gene expression and increased Mgv and StuA expression. Amino acid conservations at codons 198 and 200 in the beta tubulin gene were also investigated in order to confirm TPM resistance and reveal genetic diversity in Fusarium species. Each isolate showed conserved amino acids at 198 and 200 codons, resulting in sensitive genotypes. The bootstrap support value for genetic similarity was more than 70%. Findings obtained from this study showed that Fusarium isolates that cause head blight and crown rot in Turkey have a low level of variation in terms of phenotype and genetic characteristics. Moreover, this is the first report to show that TPM led to a potential decrease in toxin production-associated genes and increased potential of sexual/asexual reproduction genes. Results could provide improved and comprehensive data for the struggle against Fusarium pathogens.

FcMgv1, FcStuA AND FcVeA BASED GENETIC CHARACTERIZATION IN Fusarium culmorum (W.G. Smith)

Fusarium culmorum (W.G. Smith) leads to economic losses in wheat and barley fields in Turkey as well as in many countries worldwide as a result of head blight and crown rot diseases. In this study, in vitro growth capacity of 33 F. culmorum isolates originating from Turkey and the relationship between phenotypic and genetic characteristics obtained based on similarities of FcMgv1, FcStuA and FcVeA genes were investigated. Linear growth rate values were recorded at 4th and 7th days of incubation. The mean linear growth rate values ranged from 7.58±1.06 to 14.7±1.26mm/day. The isolates F2 and 18F with relatively high linear growth values and the isolates 12F and F19 with relatively low linear growth values, were selected to be used in multiloci based genotyping analysis. FcMgv1, FcStuA and FcVeA genes were amplified in lengths of 1733, 2001 and 1898bp, respectively. The genes were sequenced, aligned and then subjected to BLASTn and to maximum likelihood topology analysis. Nucleotide sequence of each gene showed maximum hit with associated genes deposited in NCBI with 0.0-0.0 E-values and 1188 to 3256 bit scores. Alignment analysis resulted in at least 89% bootstrap support. Moreover, isolates with similar linear growth rates were co-clustered in phylogenetic analysis. The findings obtained in this study showed that the three genes which are essential for fungal survival could be used in genetic characterization analysis and in revealing the associations between their genetic and phenotypic characteristics.

Bazı Antagonist Trichoderma ve Endofitik Acremonium İzolatlarının Fusarium Kök ve Kök-Boğazı Çürüklüğü Hastalıklarına Karşı Etkinliklerinin Belirlenmesi

The use of antagonist microorganisms against pathogenic organisms in organic agricultural systems was promising for biological control approach. The aim of this study was to determination of the potential biological control of some fungal isolates which characterized as endophytic and antagonistic against soil borne Fusarium culmorum (FC) and F. oxysporum f.sp. radicis lycopersici (FORL) pathogens. For this, seven isolates of endophytic Acremonium spp. that isolated from healthy wheat plants and eight isolates of antagonist Trichoderma spp., isolated from soil of organic vegetable areas, were performed as biological control agents (BCA). The agar media with hypha and mycelia of the BCAs and spore suspensions (106 spores/ml) of FC and FORL were treated for inoculation of wheat seeds and tomato seedlings. The harvested plants were statistically analyzed by some parameters (severity of crown rot disease (%DS and scale), plant lengths (cm) etc.). In conclusion, the Acremonium isolates (47.5%) were lower means of disease severity than Trichoderma isolates (74.6%) for FC and FORL assessments in wheat experiment. In tomato, the averages of disease severity between Acremonium and Trichoderma were similar while their means were lower than positive control (The Scale of DS=0.67

The influence of potassium alum, sodium bicarbonate, and chlorine treatments on banana’s crown rot disease progress

Crown rot is a post-harvest fungal disease causing significant negative impact on fruit quality. The infection mainly occurs by different etiological agents at harvest time but the symptoms appear 10-14 days later, usually after overseas transportation. The use of synthetic fungicides to control this disease is frequently restricted and regulated in banana farming, therefore it is necessary to find safe alternatives to fungicides that can reduce the incidence under acceptable threshold levels. The effect of potassium alum, sodium bicarbonate and chlorine on crown rot disease progress was assessed on organic bananas against some pathogen strains. Mycelium and conidia of strains belonging to the main fungal species identified as etiological agents of crown rot in the Dominican Republic were assessed in vitro for germination and growth against different concentrations of the substances to report their activity as fungicidal/fungistatic on artificial media and crown tissues. Results obtained correspond to those reported in disease incidence, whereby the alum mainly acts as fungistatic, the chlorine was fungicidal, and sodium bicarbonate didn't demonstrate any effect on conidia germination at the tested concentration. In packing stations, 240 hands of normally harvested green bananas were used immediately after the second washing bath in three separate treatments: 1) alum as normally adopted in packing stations, 2) 5 g L-1 of sodium bicarbonate in water, and 3) 3 ppm chlorine in water. The results showed significant differences between the different treatments. Sodium bicarbonate improved the infections causing highest disease incidence of 81%, followed by alum with 23% in comparison to the control that showed 19% of symptomatic bananas. In contrast, no symptomatic fruits were present among bananas treated with chlorine.

Distribution and Genetic Variability of Fusarium oxysporum Associated with Tomato Diseases in Algeria and a Biocontrol Strategy with Indigenous Trichoderma spp.

Fifty fungal isolates were sampled from diseased tomato plants as result of a survey conducted in seven tomato crop areas in Algeria from 2012 to 2015. Morphological criteria and PCR-based identification, using the primers PF02 and PF03, assigned 29 out of 50 isolates to Fusarium oxysporum (Fo). The banding patterns amplified for genes SIX1, SIX3 and SIX4 served to identify races 2 and 3 of Fo f. sp. lycopersici (FOL), and Fo f. sp. radicis lycopersici (FORL) among the Algerian isolates. All FOL isolates showed pathogenicity on the susceptible tomato cv. “Super Marmande,” while nine of out 10 Algerian FORL isolates were pathogenic on tomato cv. “Rio Grande.” Inter simple sequence repeat (ISSR) fingerprints showed high genetic diversity among Algerian Fo isolates. Seventeen Algerian Trichoderma isolates were also obtained and assigned to the species T. asperellum (12 isolates), T. harzianum (four isolates) and T. ghanense (one isolate) based on ITS and tef1α gene sequences. Different in vitro tests identified the antagonistic potential of native Trichoderma isolates against FORL and FOL. Greenhouse biocontrol assays performed on “SM” tomato plants with T. ghanense T8 and T. asperellum T9 and T17, and three Fo isolates showed that isolate T8 performed well against FORL and FOL. This finding was based on an incidence reduction of crown and root rot and Fusarium wilt diseases by 53.1 and 48.3%, respectively.

Occurrence and isolation of some Fusarium species associated with crown and root rot disease in some wheat fields of Duhok, IKR, Iraq

Occurrence and isolation of some Fusarium species associated with crown and root rot disease in some wheat fields of Duhok, IKR, Iraq

EFFECT OF PLANTING DISTANCE OF CERTAIN CULTIVARS ON INCIDENCE OF ROOT AND CROWN ROT DISEASES IN STRAWBERRY NURSERIES

The effect of planting distances on the development of root and crown rot diseases of strawberry in the transplanting nursery was studied in two successive seasons of 2015 and 2016. Three Super Elite mother plants of Festival, Florida and Sweet Charlie were tested. Seven Planting distances (0.6, 0.9, 1.2, 1.5, 1.8, 2.1, 2.4 m) were used between mother plants. The first three planting distances (0.6, 0.9, 1.2 m) were the standard distances used by strawberry growers in the commercial nurseries. The rest of planting distances (1.5, 1.8, 2.1, 2.4 m) represented the suggested modified distances. The obtained results showed a considerable amount of reduction (%) on root and crown rot diseases on the produced transplants of the modified planting distances. The modification of planting distances in strawberry nurseries could be used as one of banned methyl bromide alternatives.

The first report of Pestalotiopsis sp. causing crown rot disease on strawberry (Fragaria X ananassa Duch.) in Bangladesh and evaluation of fungicide activity

The first report of Pestalotiopsis sp. causing crown rot disease on strawberry (Fragaria X ananassa Duch.) in Bangladesh and evaluation of fungicide activity

Control of Postharvest Crown Rot Disease in Cavendish Banana with Aluminium Sulfate and Vacuum Packaging

Effect of alum in combination with vacuum packaging was investigated in controlling crown rot disease of Cavendish banana (Musa acuminata, AAA, Grande Naine cultivar) at 12-14 oC. Twelve week mature Cavendish banana fruits were treated with 1% (w/v) alum (Potassium aluminium sulphate), 0.5 g/L carbendazim (Positive control) or distilled water (Negative control). Treated banana samples were packed in Low Density Polyethylene bags (150 gauge) and stored at 12-14 oC. In-package gases were analysed every seven days up to 28 days of storage. Physicochemical properties (pH, firmness, TSS, TA), sensory properties (peel colour, flesh colour, aroma, flavour, taste, overall acceptability) and crown rot disease severity were determined in ripening induced fruits after each storage period. Data obtained for physicochemical properties and in-package gases were subjected to ANOVA whereas pathological and sensory properties were analysed using Kruskal-Wallis non-parametric statistical test using Minitab. At the end of 28 days of storage, O2 in all packages remained between 5.6-5.8% while CO2 remained between 5.0 to 5.1%. Further, treatment of 1% alum alone controlled crown rot disease completely up to 14 days. Most of physicochemical and sensory properties of treated banana were not adversely affected by the treatment.

English

In vitro clove essential oil (1.0%), sodium carbonate (2.0%) and sorbic, salycilic and propinic acids (0.5%) completely (100%) inhibited mycelial linear growth of Colletotrichum musae and Fusarium moniliforme, which is the cause of postharvest diseases in banana fruits. In vivo different application methods, that is, spray, soaking and dusting were tested on crown rot, neck rot, finger rot and flower end rot under artificial infestation with causal pathogens. Soaking method significantly reduced major postharvest diseases incidence in banana fruits than spray and dusting treatments. Soaking banana fruits in clove suspension (2%) and sodium carbonate (4.0%) was the best treatment that completely inhibited (100%) crown rot and flower end rot diseases and significantly reduced finger rot and neck rot diseases. So, clove oil and sodium carbonate were the most promising agents for controlling major postharvest diseases of banana fruits as eco-friendly and alternative synthetic fungicides. &nbsp; Key words: Banana, antioxidants, fungi, diseases, essential oil, salts.