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Purpose: Stem-end rot (SER) is a major disease of mango that causes serious postharvest losses. Application of fungicides is environmentally unsound and is being practiced currently in its control. This study was conducted to develop essential oil treatment systems as eco-friendly strategies to control SER of Karthakolomban mango and to determine the pathogenicity of several SER associated fungi.Research Method: Pathogenicity of four fungal isolates in SER was assessed by inoculating them on Karthakolomban mango fruits. Karthakolomban mango fruits were subjected to spray and fumigation treatments using four essential oils and their pathological, physicochemical and sensory properties were evaluated after a 8-day storage at 12 -14 ºC.Findings: Lasiodiplodia theobromae, Pestalotiopsis sp., Phomopsis sp. and Xylaria feejeensis were the major SER pathogens of mango. X. feejeensis was identifi ed as a SER pathogen for the fi rst time in Sri Lanka. Spray and fumigation treatments conducted using basil, clove, cinnamon leaf and cinnamon bark oils eff ectively controlled SER of Karthakolomban mango stored at 12 -14 ºC for 8 days. Mango sprayed with 1.6 µL/mL cinnamon bark oil has displayed no SER after induced ripening. None of the treatments caused drastic alterations in physicochemical and sensory properties of mango.Research Limitations: Storage period of mango was restricted to 8 days due to the initiation of natural ripening which was the major limitation to achieving a further enhanced shelf life.Originality/value: The treatment strategies developed by this research could be commercialized as biosafe SER control strategies in reducing postharvest losses of mango in the local and international trade. *Percentage Stem-End Rot; Each data point represents the mean of eight replicates ± standard error. 1 Means sharing a common letter(s) are not signifi cantly diff erent by Tukey's pair-wise comparison test at p < 0.05. 2 Means sharing a common letter(s) are not signifi cantly diff erent by Kruskal Wallis non-parametric test at p < 0.05.

Unripe mangoes contain a network of minute latex canals in its exocarp, outer mesocarp and the pedicel. Latex, when retrieved, separates into an upper oily layer containing antifungal resorcinols and a lower aqueous layer with chitinase activity. Latex disappears in coincidence with ripening and decline of fruit resistance to fungal pathogens. The present study investigated if retention of latex at harvest enhances fruit resistance and reduces anthracnose and the stem-end rot (SER) development during ripening. Latex was retained by harvesting fruit with a portion (approximately 1 cm) of pedicel while in the controls, latex was drained off by removing the pedicel. Anthracnose and SER development from natural infections or following artificial inoculation was assessed at ripe stage. The results showed a significant reduction in the incidence and severity of anthracnose in the cultivar 'Willard' susceptible to anthracnose when latex was retained at harvest. There was delayed SER development when latex was retained in the susceptible cultivar 'Karutha Colomban'. A negative trend was observed between the pedicel length and anthracnose or SER level in cultivars susceptible to the two respective diseases. The fruit peel in which latex was retained had greater chitinase activity. The reduction of anthracnose and SER could be due to the greater resorcinols and chitinase activity respectively in latex-retained fruit. The results indicate a direct involvement of latex in fruit resistance and the possibility of its manipulation to protect ripe fruit from fungal rotting.

Increasing drug resistance of pathogens and negative consequences of antibiotic usage has led to the search for alternative medicines from nature. Many plants have been exploited to cure infectious diseases from time immemorial. The present investigation evaluated the antimicrobial and phytochemical properties of Artocarpus heterophyllus i.e. Jack fruit (Kos in Sinhala) and Artocarpus altilis i.e. Bread fruit (Dhel in Sinhala) leaf and stem bark extracts. Hexane, dichloromethane and ethanol were used as extraction solvents and test organisms were Escherichia coli, Micrococcus luteus, Aspergillus niger and Trichoderma sp. A disc diffusion test was adopted to test the susceptibility of the selected microbes to the extracts while Minimum inhibitory concentration (MIC) was determined using serial dilution of extracts. Phytochemical screening was carried out by specific chemical identification tests. Bioassay data were statistically analyzed using two-way ANOVA (SPSS 20 at 95% confidence level). Ethanolic stem bark extracts (30mg/ml) of A.heterophyllus and A.altilis possessed significant antibacterial activity against Escherichia coli with 9.50 ± 0.44 mm and 7.49 ± 0.28 mm inhibition zone radii respectively. Dichloromethane extracts of leaf and stem bark showed lesser antibacterial activity against both of the bacteria with inhibition zones of 3.00 ± 0.34 mm to 5.66 ± 0.16 mm while hexane extracts did not show any antibacterial activity. Antifungal activity on the other hand was not detected in any of the extracts. Bacterial antibiotic tetracycline and fungal antibiotic ketoconazole which were used as positive controls were more effective even at 1/10 concentration compared to all the plant extracts tested. Phytochemical screening confirmed the presence of phytosterols, anthraquinone, terpenoids, phenols, glycosides, flavonoids and diterpenes in both of the trees. These results confirm the potential antibacterial activity of A.heterophyllus and A.altilis

Purpose The purpose of this paper is to identify socio-economic/demographic characteristics and to evaluate the knowledge on different open distance learning (ODL) concepts of BSc undergraduates of The Open University of Sri Lanka (OUSL) at first registration. Design/methodology/approach The surveying technique was adapted with a piloted structured questionnaire consisting of two components. The structured component was used to evaluate personal, socio-economic and demographic data. The open ended component evaluated the student’s perception on ODL concepts. The questionnaire was randomly adapted to 456 (35 percent Colombo Regional Centre (CRC) registrants) prospective BSc undergraduates at first registration time at the CRC in 2014. Data collected from the structured component were frequency tabulated and cross-tabulated with the SPSS computer software. Responses of the open ended part were examined, categorized and the frequency percentages of each response category were calculated. Findings The structured component recognized that the majority of BSc undergraduates of the OUSL represent employed (53 percent), late adolescents (92 percent below age 27) who reside in rural or semi-urban areas (75 percent). They belong mostly to the lower middle class and 69 percent are from families which have a monthly family income below SLR30,000/(USD208). Answers of the open ended component on ODL concepts recognized that, prior knowledge on ODL concepts were developed by most BSc undergraduates. Approximately 50 percent of respondents perceived OUSL as an institute which facilitates working people by conducting part time-based or distance mode education with self-learning features. In total, 56.9 percent students perceived the role of an ODL teacher correctly as a facilitator or a guide. The educational process was perceived correctly as an ODL system by 52 percent, while the remainder also identified the system to be a more self-study and student centered flexible learning system. However, the role of a BSc student at OUSL was recognized as self-independent learners by only 36.7 percent and the majority had no clear perception of the role they have to play as an ODL student. Hence, more attention should be paid to make students recognize the role they have to play in an ODL system in order to succeed at OUSL. Originality/value Although research has been carried out periodically on the process of ODL education system at OUSL, on the graduate (output) and dropouts, etc., not many have focused on the nature of input such as characteristic features of first registrant and their prior knowledge on ODL. As the output invariably depends on the input and the process, this type of survey is timely and novel.