Major Tropical Fruit Research Articles

A Comprehensive Review on Deep Learning for Accurate Papaya Disease Identification

This comprehensive review delves into the application of deep learning techniques for the precise identification of papaya diseases. With the increasing importance of papaya as a major tropical fruit crop, the accurate and timely diagnosis of diseases is crucial for effective disease management. The paper synthesizes recent advancements in deep learning methodologies, including convolutional neural networks (CNNs), recurrent neural networks (RNNs), and their variants, applied to image-based disease identification in papaya plants. The review assesses the strengths and limitations of various deep learning models, explores the integration of multi-modal data sources, and evaluates the performance metrics employed for disease detection accuracy. Additionally, the study discusses challenges and future directions in leveraging deep learning for papaya disease identification, aiming to provide a comprehensive understanding of the current state and potential advancements in this critical agricultural domain.

Advancement of non-destructive spectral measurements for the quality of major tropical fruits and vegetables: a review.

The quality of tropical fruits and vegetables and the expanding global interest in eating healthy foods have resulted in the continual development of reliable, quick, and cost-effective quality assurance methods. The present review discusses the advancement of non-destructive spectral measurements for evaluating the quality of major tropical fruits and vegetables. Fourier transform infrared (FTIR), Near-infrared (NIR), Raman spectroscopy, and hyperspectral imaging (HSI) were used to monitor the external and internal parameters of papaya, pineapple, avocado, mango, and banana. The ability of HSI to detect both spectral and spatial dimensions proved its efficiency in measuring external qualities such as grading 516 bananas, and defects in 10 mangoes and 10 avocados with 98.45%, 97.95%, and 99.9%, respectively. All of the techniques effectively assessed internal characteristics such as total soluble solids (TSS), soluble solid content (SSC), and moisture content (MC), with the exception of NIR, which was found to have limited penetration depth for fruits and vegetables with thick rinds or skins, including avocado, pineapple, and banana. The appropriate selection of NIR optical geometry and wavelength range can help to improve the prediction accuracy of these crops. The advancement of spectral measurements combined with machine learning and deep learning technologies have increased the efficiency of estimating the six maturity stages of papaya fruit, from the unripe to the overripe stages, with F1 scores of up to 0.90 by feature concatenation of data developed by HSI and visible light. The presented findings in the technological advancements of non-destructive spectral measurements offer promising quality assurance for tropical fruits and vegetables.

Fusarium Species Associated with Diseases of Major Tropical Fruit Crops

Mango, banana, papaya, pineapple, and avocado are categorized as major tropical fruits grown for local consumption, export, and sources of income to the growers. These fruit crops are susceptible to infection by Fusarium in the field, and after harvest, it causes root rot, vascular wilt, stem rot, and fruit rot. Among the most common and economically important Fusarium species associated with diseases of major fruit are F. oxysporum and F. solani, which are prevalent in tropical regions. Other species include F. incarnatum, F. proliferatum, and F. verticilliodes. Most of these species have a wide host range and infect different parts of the plant. Due to the economic importance of these fruit crops, this review highlights the diseases and Fusarium species that infect fruit crops in the field as well as after harvest. Updated information on Fusarium species infecting major tropical fruit crops is important as disease management in the field and after harvest often relies on the causal pathogens. Moreover, major fruit crops are traded worldwide, and newly recorded species associated with these fruit crops are important for biosecurity purposes. Information on the diseases and causal pathogens may help to facilitate routine diagnosis and planning of suitable plant disease management methods.

RETRACTED: Valorization of tropical fruits waste for production of commercial biorefinery products – A review

Tropical fruit wastes (TFW) are considered as the major source of food and nutrition in the topical countries. In the recent years, modernization of agriculture has increased the tropical fruit production. Higher fruit production led to an increasing abundance in the tropical fruit waste. In general, the tropical fruit waste has no economic value and ends up in landfill. But in recent years it was observed that the tropical fruit waste can be valorized to produce value-added products ranging from compost, phytochemicals, and food products to biofuels. The tropical fruit waste has great potential to produce useful products in tropical areas. This review literature is an endeavor to understand the major tropical fruit wastes and their composition. The review presents a detailed investigation on tropical fruit waste composition, its conversion potential, role of microbes in waste valorization, production of commercially valuable products and future perspectives in waste valorization.

Comparative Investigation on the Phytochemicals and Biological Activities of Jackfruit (Artocarpus heterophyllus Lam.) pulp from Five Cultivars.

Jackfruit is one of the major tropical fruits, but information on the phytochemicals and biological benefits of its pulp is limited. In this study, the phytochemicals and biological activities including antioxidant, antitumor and anti-inflammatory activities of five jackfruit pulp cultivars (M1, M2, M3, M7 and T5) were comparatively investigated. A total of 11 compounds were identified in all cultivars of jackfruit pulp, among which 4-hydroxybenzoic acid, caffeic acid, ferulic acid and tryptophan N-glucoside were reported for the first time in jackfruit. T5 exhibited the highest total phenolic content (7.69 ± 0.73mg GAE/g DW), antioxidant capacity (109.8, 96.7 and 207mg VCE/g DW for DPPH, ABTS and FRAP, respectively), antitumor activity (80.31%) and anti-inflammatory activity (78.44%) among five cultivars. These results can provide a reference for growers to choose jackfruit cultivar and offer an insight into the industrial application of jackfruit pulp derived-products.

Pharmacological Potentials and Nutritional Values of Tropical and Subtropical Fruits of India: Emphasis on their Anticancer Bioactive Components.

Fruits are an important dietary component, which supply vitamins, minerals, as well as dietary fiber. In addition, they are rich sources of various biological and pharmacologically active compounds. Among these, temperate fruits are well studied for their pharmacological potentials, whereas tropical/subtropical fruits are less explored for their health impacts. In India, most of the consumed fruits are either tropical or subtropical. This mini review aims to provide a health impact of major tropical and sub-tropical fruits of India, emphasizing their anticancer efficacy. In addition, the identified bioactive components from these fruits exhibiting anticancer efficacy are also discussed along with the patent literature published. The literature was collected from various repositories, including NCBI, ScienceDirect, Eurekaselect, and Web of Science; literature from predatory journals was omitted during the process. Patent literature was collected from google patents and similar patent databases. Tropical fruits are rich sources of various nutrients and bioactive components including polyphenols, flavonoids, anthocyanin, etc. By virtue of these biomolecules, tropical fruits have been shown to interfere with various steps in carcinogenesis, metastasis, and drug resistance. Their mode of action is either by activation of apoptosis, regulation of cell cycle, inhibition of cell survival and proliferation pathways, increased lipid trafficking or inhibiting inflammatory pathways. Several molecules and combinations have been patented for their anticancer and chemoprotective properties. Overall, the present concludes that Indian tropical/ subtropical fruits are nutritionally and pharmacologically active and may serve as a source of novel anticancer agents in the future.

An Empirical Analysis of the Import Demand of Agricultural Products in Korea

세계화의 진전으로 글로벌기업은 두 개 이상의 국가가 참여하는 생산 네트워크인 글로벌 가치사슬(GVC; Global Value Chain)을 적극적으로 구축하였다. 그러나 공급망을 마비시키는 대규모 재해가 빈번해지고 있으며 최근 코로나19 발생으로 글로벌 공급망 위기는 고조되고 있다. 공급망 위기는 농업 분야에도 영향을 미치고 있는데 우리나라 농업은 영세성과 낮은 생산성으로 인해 쌀을 제외한 대부분 곡물을 수입에 의존하고 있어 국제곡물의 공급망에 발생하는 다양한 불확실성을 대비하기 위해 우리나라 농산물의 수입구조에 대한 분석이 필요한 상황이다. 본고는 우리나라 전체수입과 농축수산물, 농축산물, 7대 곡물, 6대 열대과일, 5대 축산물에 대한 수입수요함수를 추정하고 수입수요 결정에 영향을 미치는 요인과 정도에 대해서 측정하였다. 분석자료의 시계열 안정성을 확보하기 위하여 단위근 검정을 실시하고 차분변수를 활용하여 OLS 분석을 하였다. 분석을 통해 우리나라 수입수요는 실질실효환율(REEXR), 환율(EXR), 경제성장률(GROWTH), 국민총소득(GNI), 소비자물가지수(CPI) 등에 의해 영향을 받는다는 결과를 얻었다. 수입물가(IMPR) 상승은 수입재의 가격을 인상시켜 수입을 감소시킬 것이라는 예상하에 분석한 결과 1% 유의수준하에서 수입물가상승은 수입을 증가시킨다는 분석결과를 얻었다. 우리나라의 농산물 수입은 국내 농업생산성의 한계를 극복하기 위한 대안으로 부각되고 있지만, 중장기적으로 국내 농산물 여건을 개선하여 경쟁력을 향상시키고 수입시장을 관리할 수 있는 여건을 마련할 필요가 있다고 판단된다.With the progress of globalization, global companies have actively established the Global Value Chain (GVC), a production network involving two or more countries, but large-scale disasters that paralyze the supply chain are frequent and the global supply chain crisis is escalating. Due to the small size and low productivity of the agricultural sector, Korea relies on imports of most grains except rice. In this study, the import demand function for Korea s total imports, agricultural, livestock, agricultural, livestock, seven major grains, six major tropical fruits, and five major livestock products was estimated and the effect of factors affecting import demand determination was empirically analyzed. As for the analysis method, a unit root test was performed to secure the time series stability of the analysis data, and OLS analysis was performed using difference variables. The following results were derived through empirical analysis. The analysis results were derived that Korea s import demand is affected by the real effective exchange rate (REEXR), exchange rate (EXR), economic growth rate (GROWTH), gross national income (GNI), and consumer price index (CPI). In particular, as a result of an analysis under the expectation that an increase in import prices(IMPR) will increase the price of imported goods and reduce imports, an analysis result was derived that an increase in import prices increases imports under a 1% significance level. Based on the analysis results, Korea s agricultural imports are emerging as an alternative to overcome the limitations of domestic agricultural productivity, but it is necessary to improve domestic agricultural conditions in the mid- to long-term to improve competitiveness.

Cosmeceutical Potential of Major Tropical and Subtropical Fruit By-Products for a Sustainable Revalorization.

The increasing production of tropical fruits followed by their processing results in tons of waste, such as skins or seeds. However, these by-products have been reported to be rich in bioactive compounds (BACs) with excellent properties of interest in the cosmeceutical industry: antioxidant, anti-aging, anti-inflammatory, antimicrobial and photoprotective properties. This review summarizes the tropical fruits most produced worldwide, their bioactive composition and the most important and studied therapeutic properties that their by-products can contribute to skin health, as well as the different approaches for obtaining these compounds using techniques by conventional (Soxhlet, liquid-liquid extraction or maceration) and non-conventional extractions (supercritical fluid extraction (SFE), ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), pressurized liquid extraction (PLE) and two-phase aqueous system), followed by their identification by HPLC-MS or GC-MS analysis. Moreover, this work encompasses several studies that may prove the effects of seeds and skins from tropical fruits against oxidative stress, hyperpigmentation, acne, aging or UV radiation. Therefore, the investigation of functional components present in tropical fruit by-products under a circular bioeconomy model could be of great interest for the cosmeceutical industry and a very promising option for obtaining new cosmeceutical formulations.

Species Complex of Coccinellids on Major Tropical Fruits in Different Agro Climatic Zones of Tamil Nadu state of India

Studies were undertaken on the occurrence of coccinellids on various hosts of fruit crops in different zones of Tamil Nadu, bio-ecology of Cryptolaemus montrouzieri and Scymnus coccivora, behavioural response of C. montrouzieri to different species of mealybugs, toxicity of insecticides to the grubs and adults of C. montrouzieri and field efficacy of C. montrouzieri on guava mealybugs. Survey made in various zones of Tamil Nadu revealed that eight species of coccinellids viz., Chielomenes sexmaculatus, S. coccivora, C. montrouzieri, Scymnus nubilus, Scymnus lateomaculatus, Calvia sykesii, Anegleis cardoni and Chilochorus melas were found to feed on different species of mealybugs and aphids. C. montrouzieri followed by S. coccivora and C. sexmaculatus were recorded as predominant predators. Aphids species viz., Aphis gossypii, Aphis punicae, Toxoptera citricidus, T. aurantii and T. odinae and mealybug species viz., Planococcus citri, P. lilacinus, Ferrisia virgata, Rastrococcus iceryoides and Maconellicoccus hirsutus were observed in the surveyed locations. Among the different mealybug and aphid species, P. citri and A. gossypii were found to be the dominant prey for the coccinellids.

Utilization of Mango, Apple and Banana Fruit Peels as Prebiotics and Functional Ingredients

Among the waste by-products generated by the fruit industry (peels, seeds, and skins), fruit peel constitutes the major component. It is estimated that fruit peel accounts for at least 20% of the fresh fruit weight. Fruit peels are considered as major sources of dietary fiber and anticipated to be successfully utilized as prebiotics. This study examined the chemical composition, functional properties and the prebiotic effects of three major tropical fruit peels (apple, banana and mango). The prebiotic effect was tested using three commercial probiotic strains (Lactobacillus rhamnosus, L. casei and Bifidobacterium lactis) individually and in combination. Each probiotic culture was fortified with different concentration (0%, 2% and 4%) of selected fruit peel powder (FPP). Results revealed that all tested FPP significantly (p < 0.05) enhanced the probiotics viable counts, which reached >10 logs after 24 h of incubation. However, the concentration of 2% and 4% FPP showed no significant differences (p > 0.05) on the probiotic viable counts. Additionally, the prebiotic effects of FPP were the same when applied to individual and mixed cultures. This investigation demonstrated that small amount (2%) of apple, banana and mango peel powder could be successfully utilized as prebiotics to enhance the growth of lactic acid bacteria (LAB). Additionally, the studied physical and chemical characteristics of FPP demonstrated their potential applications in the food and pharmaceutical industries as functional ingredients.

Computational Identification of miRNAs and Temperature-Responsive lncRNAs From Mango (Mangifera indica L.).

Mango is a major tropical fruit in the world and is known as the king of fruits because of its flavor, aroma, taste, and nutritional values. Although various regulatory roles of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) have been investigated in many plants, there is yet an absence of such study in mango. This is the first study to provide information on non-coding RNAs (ncRNAs) of mango with the aims of identifying miRNAs and lncRNAs and discovering their potential functions by interaction prediction of the miRNAs, lncRNAs, and their target genes. In this analysis, about a hundred miRNAs and over 7,000 temperature-responsive lncRNAs were identified and the target genes of these ncRNAs were characterized. According to these results, the newly identified mango ncRNAs, like other plant ncRNAs, have a potential role in biological and metabolic pathways including plant growth and developmental process, pathogen defense mechanism, and stress-responsive process. Moreover, mango lncRNAs can target miRNAs to reduce the stability of lncRNAs and can function as molecular decoys or sponges of miRNAs. This paper would provide information about miRNAs and lncRNAs of mango and would help for further investigation of the specific functions of mango ncRNAs through wet lab experiments.

Phytotoxic Metabolites Produce by Fusarium oxysporum f. sp. cubense Race 2.

Banana is a major tropical fruit crop but banana production worldwide is seriously threatened due to Fusarium wilt. Fusarium oxysporum f. sp. cubense (Foc), the causal agent of Fusarium wilt of banana (also referred as Panama disease) is an asexual, soil inhabiting facultative parasite. Foc isolates can be classified into three races that are not defined genetically, but for their pathogenicity to different banana cultivars. Despite mycotoxins being some of the best studied virulence factors of phytopathogenic fungi and these have been useful for the prediction of Foc virulence on banana plants, toxins produced by Foc race 2 strains have not been previously identified. The aim of this contribution was to identify the phytotoxic metabolites closely related to banana wilt caused by a Foc race 2 strain. We used an in vitro bioassay on detached banana leaves to evaluate the specificity of the microbial culture filtrates before a partial purification and further identification of Foc race 2 phytotoxins. A 29-day-old host-specific culture filtrate was obtained but specificity of culture filtrate was unrecovered after partial purification. The non-specific phytotoxins were characterized as fusaric acid, beauvericin, and enniatin A. Whereas some, if not all, of these phytotoxins are important virulence factors, a proteinaceous fraction from the specific 29-day-old culture filtrate protected the leaves of the resistant banana cultivar from damage caused by such phytotoxic metabolites.

Страны Латинской Америки и Россия в международной торговле основными тропическими фруктами

The orientation of a part of the population of economically developed countries to a healthy diet, the spread of ideas of vegetarianism, concern for the environment, and relatively higher incomes contributed to an increase in demand for fruits, berries and nuts of tropical and subtropical origin. Some of them, in particular bananas, oranges, tangerines, lemons, have become common food products and practically everyday consumption for the majority of the population of developed countries in the last quarter of the 20th century. In the future, some other types of fresh fruit and berry products from the tropics and subtropics (for example, pineapple, kiwi, avocado) gradually, due to increased production and international trade, also became more economically available to the ordinary consumer. Based on the analysis of statistics from the Food and Agriculture Organization of the United Nations for 1961-2019, the article shows a number of trends in international trade (for exports) of major tropical fruits are reflected, with a deeper look at the participation of Latin American countries in this process. It was revealed that some states of this region, such as Mexico, Ecuador, Guatemala, Costa Rica, Colombia, Honduras, Peru, Brazil, Chile, occupy significant positions in the supply of bananas, pineapple, avocado, mango, papaya to the world market. Currently, Russia is one of the largest countries in the world in terms of imports of fruit and berry products, therefore, the issue of its participation as a subject of demand in the world tropical fruit market is raised.

Stem-end rot in major tropical and sub-tropical fruit species

Stem-end rot (SER) is one of the most destructive postharvest diseases affecting some tropical and sub-tropical fruits. The disease is caused by several fungal pathogens, including Botryosphaeriaceae species. In mango, Dothiorella dominicana, D. mangiferae, Lasiodiplodia theobromae, Phomopsis mangiferae, Cytosphaera mangiferae, Pestalotiopsis sp. endophytically colonize the inflorescence in the orchard or field. Fungi may occur endophytically in the stem tissue of the trees prior to inflorescence emergence. During the endophytic stage, the fungi colonize the phloem and xylem at stem-end and, after fruit ripening, some fungi become necrotrophic and colonize the fruit pulp causing SER. The SER pathogens in other fruit species, including ripe avocado or papaya, are not known to undergo an endophytic phase. Stem-end rot is a disease that is difficult to control. Preharvest cultural practices and selection of resistant varieties are beneficial to reduce field infections. Studies have shown that numerous control options, involving cultural, chemical (fungicides, essential oils) and biological approaches, are available to manage SER through either direct inhibition of fungi or induction of host defenses. These may be used individually or integrated manner. The most common and effective practice for controlling the SER is pre- and postharvest application of synthetic fungicides. With the new tools that are currently available, and expected to emerge, there is a possibility of a better understanding the host–pathogen or host-microbiota interactions within the stem-end region, leading to newer technologies as alternatives to toxic synthetic fungicides for the management of SER in fruits.

Screening of physicochemical and functional attributes of fermented beverage (wine) produced from local mango (Mangifera indica) varieties of Uttar Pradesh using novel saccharomyces strain

Mango (Mangifera Indica L.) is a major tropical fruit rich in sugar, organic acids and flavonoids, making it suitable fruit for wine making. In the present study, five varieties of mango (Baganpalli, Langra, Dashehari, Alphonso, and Totapuri) were utilized for wine production using two different yeast strains namely, Saccharomyces cerevisiae MTCC 178 and isolated yeast. The physiochemical analysis of wine produced from chosen mango varieties showed that North Indian local mango variety (Dashehari) gave better results in terms of organoleptic and functional attributes. The Saccharomyces cerevisiae MTCC 178 treated Dashehari wine possessed 6.1 ± 0.26% TSS, 2.1 ± 0.08% reducing sugar, 0.657% titratable acidity, 0.11 ± 0.00% volatile acidity, 12% ethanol (v/v) and pH 3.7 ± 0.10 comparable to Baganpalli mango wine. HPLC analysis of Saccharomyces cerevisiae MTCC 178 inoculated Dashehari mango wine revealed the presence of primarily; gallic acid (RT-4.4 min), Galloyl-A-type, procyanidin (RT-5.2 min), 2,2,6-Trimethyl-6-vinyltetrahydropyran (RT-8.91 min), β-Pinene (RT-11.47 min) and Caffeoyl-quinic acid (RT-12.15 min) showing potential antioxidant, anti-cancerous, anti-inflammatory and antimicrobial properties. The local mango varieties wine showed significant (p < 0.05) physicochemical properties, antioxidant potential and ethanol content comparable to Baganpalli wine and was cost effective.

Non-destructive prediction and detection of internal physiological disorders in 'Keitt' mango using a hand-held Vis-NIR spectrometer

Mango (Mangifera indica L.) is a major tropical fruit that can develop internal physiological disorders at late ripening stages. These include jelly seed characterized by a transparent and jelly tissue around the seed that eventually becomes a brown ring enclosing the seed, and black flesh characterized by a diffuse brown discoloration that covers the seed. Both disorders can result in high postharvest losses due to the fact that little information is available about mechanisms involved and efficient control approaches. The objective of this study was to establish the feasibility of using a visible and near-infrared (Vis-NIR) portable spectrometer for predicting at harvest and detecting mangoes with internal disorders, such as jelly seed and black flesh after storage. A total of 141 'Keitt' mangoes from two commercial harvests were measured spectrally between 400–1100 nm on two opposite cheeks, at harvest and after 30 d at 12 °C. Spectra data and the incidence of jelly seed and black flesh after storage were used to develop classification models using logistic, linear discriminative analyses (LDA), supporting vector machine, functional data and random forest modeling approaches. The results show that wavelengths between 550 and 650 nm can be used to predict at harvest and detect after storage, fruit with internal physiological disorders, such as jelly seed and black flesh. However, it was not possible to differentiate internal disorders from each other. The spectral data show that healthy fruit have higher reflectance intensity than jelly seed and black flesh ones, both at harvest and after storage. The best classification models were obtained with Logistic and LDA model development approaches. In the validation process for internal disorder prediction at harvest, the Logistic model showed accuracy of 65 %, sensitivity of 78 % and specificity of 49 %, whereas the LDA model showed accuracy of 63 %, sensitivity of 76 % and specificity of 46 %. In the validation process for detecting internal disorders after storage, the Logistic model showed accuracy of 71 %, sensitivity of 75 % and specificity of 67 %, whereas the LDA model showed accuracy of 76 %, sensitivity of 78 % and specificity of 73 %. In conclusion, Vis-NIR technology associated with Logistic and LDA modeling approaches can be used to predict at harvest and detect after storage the incidence of jelly seed and black flesh in mangoes.

High density orcharding and canopy management of some tropical and subtropical fruits

High density planting (HDP) is a highly efficient and advanced production system of fruit cultivation. In most of the temperate tree and nut crops it is now commercially followed all over the world because of availability of suitable dwarfing rootstock to control tree vigor. Major tropical fruit crops are either propagated by suckers (banana, pineapple), seed (papaya) or by layering (guava) and grafting (mango). The use of dwarfing rootstocks, as in many temperate tree fruits, is not possible/available in most of the commercial tropical fruits for high density planting. High density planting is one of the novel methods to achieve high productivity per unit area both in short duration and perennial horticultural crops. High yield and high fruit quality can be achieved with a high-density orchard when the orchard has good light distribution throughout the tree canopy and there is a balance between vegetative growth and cropping. Many variables must be included in making a decision about spacing. Tree vigor and growth habit as influenced by cultivar and rootstock (where it could be utilized) are important. The ultimate limit on productivity of any crop is the amount of photosynthetically-active radiation (PAR) intercepted. Much of the planning that goes into the design of HDP orchards is actually based on average light interception over the life of the planting. This involves both minimizing the amount of light which strikes the ground and providing canopy structures in which the largest amount of canopy receives optimum light intensity. A tree with a large portion of its volume devoted to bearing has a greater potential for productivity than one with most of its volume devoted to tree support, middles or other functions. In India, HDP has been proved useful in many tropical and subtropical fruit crops e.g., mango, citrus, pineapple, banana, guava litchi, and papaya. The productivity of fruit crops depends on several factors, poor management of canopy architecture being the most important one. The fruiting potential of the trees is largely governed by their architecture, canopy density and photosynthetic efficiency. Canopy in a fruit tree refers to its physical composition comprising of the stem, branches, shoots and leaves. While, the canopy density is determined by the number, length and orientation of stem, branches and shoots. Tree canopy management, especially size control has become a priority for reducing production cost and increasing fruit yield and quality. The objective of canopy management is to optimize the plant model in such a way so that it may intercept maximum light by tree training, pruning, branch and tree orientation. Some of the basic principles in canopy management are: maximum utilization of the light, avoidance of the buildup of micro-climate congenial for the diseases and pests, convenience in carrying out the cultural operations, maximizing the productivity and quality and economy in obtaining the required canopy architecture.

Trichoderma harzianum en pre-transplante aumenta el potencial agronómico del cultivo de piña

Pineapple is one of the major tropical fruits in Ecuador. Because of the demand for products and foods free of pesticide, using Trichoderma constitutes an important alternative to this crop. For these reasons, the aim was to evaluate the effect of the commercial product TRICHO WP-D® based on T. harzianum applied in pre-planting on several agronomic traits of pineapple variety MD-2. The research was conducted in crop conditions at Santo Domingo de los Colorados City, Ecuador. Different doses of the commercial product based on T. harzianum (1x108 cfu g-1): 0, 400, 600 and 800 g ha-1, were applied in pre-planting directly into the soil. At 6 months after sowing, plant height, number of leaves per plant, length of radicle, fresh weight of plants and incidence of diseased plants were evaluated. A randomized complete block design was used with four treatments (doses) and four replications. Tukey test (p ? 0.05) was employed to compare the treatment means. They were also correlated (Pearson correlation) the doses and all agronomic variables. Application of T. harzianum on pre-planting positively affect the plant height, number of leaves per plant, length of radicle and, fresh weight of plants, and negatively the incidence of diseased plants of pineapple crop. Doses used of T. harzianum were correlated only with the plant height and the incidence of diseased plants.

Identification of an acidic endo-polygalacturonase from Penicillium oxalicum CZ1028 and its broad use in major tropical and subtropical fruit juices production

Endo-polygalacturonases play an important role on depectinization in fruit juices industry. A putative endo-polygalacturonase gene PoxaEnPG28A was cloned from Penicillium oxalicum CZ1028. PoxaEnPG28A consisted of a putative signal peptide and a catalytic domain belonging to glycoside hydrolase family 28, and it shared 72% identity with that of a functionally characterized endo-polygalacturonase from Trichoderma harzianum. Gene PoxaEnPG28A was successfully expressed in Pichia pastoris with a high yield of 1828.7U/mL. The purified recombinant enzyme PoxaEnPG28A hydrolyzed polygalacturonic acid in endo-manner releasing oligo-galacturonates. PoxaEnPG28A showed maximal activity at pH 5.5 and 55°C, and was stable between pH 3.0 to 10.0 and below 45°C. The kinetic constants Km and Vmax of PoxaEnPG28A were calculated as 1.57g/L and 14,641.29U/mg, respectively. PoxaEnPG28A significantly improved the yields of fruit juices from banana, plantain, papaya, pitaya and mango. The high production level of the recombinant enzyme PoxaEnPG28A by P. pastoris and remarkable catalytic activity of PoxaEnPG28A toward five kinds of fruit juices made the enzyme a potential application in agriculture and food industries.

Genome-Wide Identification and Characterization of Nucleotide-Binding Site (NBS) Resistance Genes in Pineapple

Pineapple is a major tropical fruit and the most important crop processing CAM photosynthesis. It originated in southwest Brazil and northeast Paraguay and survived the harsh, semi-arid environment. Disease resistance genes have contributed to the survival and thriving of this species. The largest class of disease resistance (R) genes in plants consists of genes encoding nucleotide-binding site (NBS) domains. The sequenced genome of pineapple (Ananas comosus (L.) Merr.) provides a resource for analyzing the NBS-encoding genes in this species. A total of 177 NBS-encoding genes were identified using automated and manual analysis criteria, and these represent about 0.6 % of the total number of predicted pineapple genes. Five genes identified here contained the N-terminal Toll/Interleukin-l receptor (TIR) domain, and 46 genes carried the N-terminal Coiled-Coil (CC) motif. A majority of these NBS-encoding genes (84 %) contained a leucine-rich repeat (LRR) domain. A total of 130 of 177 (73 %) of these NBS-encoding genes were distributed across 20 pineapple linkage groups. The identification and characterization of NBS genes in pineapple yielded a valuable genomic resource and improved understanding of R genes in pineapple, which will facilitate the development of disease resistant pineapple cultivars.