International Letters of Natural Sciences Vol. 7

Abstract: The present investigation is aimed at studying the effect of ethrel on the ripening of off-season fruits of Mangifera indica L. var. Neelum. The control fruits were kept in the laboratory naturally while the experimental fruits were treated with different concentrations of ethrel (100, 200 and 300 ppm). In control fruits, partial ripening led to incomplete metabolic changes, which did not alter the presence of sourness in the fruits. Hence, they were not fit to be eaten. On the other hand, the fruits treated with different concentrations (100, 200 and 300 ppm) of ethrel ripened on 13^th day, 11^th day and 9^th day respectively after treatment. The colour changed from green greenish to yellow and the fruits were palatable in nature. The starch decreased during ripening, both in the treated and control fruits. On the other hand, the sugar, α-amylase, β-amylase, activities increased. Among the different 100, 200 and 300 ppm ethrel treatments, the 200 ppm alone had the optimum effect on the ripening of off-season fruits of Mangifera indica L. var. Neelum.

Abstract: Timer decay is caused by primarily enzymatic activities of microorganisms. For the first time fungal diversity of timber degrading fungi was studied in Gujarat, India. Timber Degrading Fungi belonging to Aphyllophorales are economically important as many of these cause serious damage in sawmills of Gujarat. To find out the association of the timber degrading fungi and timber decay problems in sawmills a survey was conducted during 2007 to 2011 in different sawmills of 5 districts of Gujarat i.e. Vadodara, Ahmedabad, Bharuch, Rajkot and Jamnagar. In the present study teak wood present in sawmills was infected with 14 types of fungi in which Lenzites sterioides and Trametes versicolor damaged the wood severely was reported for the first time. In all 94 sawmills were surveyed, the 28 sawmills were from Vadodara, 29 from Ahmedabad, 12 from Bharuch, 21 from Rajkot and 4 from Jamnagar. Out of 94 sawmills survyed, 84 sawmills were having timber rotting fungi associated with wood. Maximum fifteen and thirteen fungal species were observed in saw mills of Chhani road, followed by 11 in Station road, 7 in Dhabhoi road and 6 in Harni, Vadodara. Fours woods uninfected are Beyo, Marinty, Ash, and Arjun. Fourteen different types of fungi were found associated with teak, followed by seven in pinus, madhuca, Acacia nilotica, six in babul, neem, four in tamarind, Pithacoelobium and three in mango, Eucalyptus, African Mahagoni, Kapoor, Peltophoram rouxburghii, Derris pinnata wood respectively. The commonly observed timber decaying fungi were Schizophyllum commune, Flavodon flavus and Ganoderma lucidum belonging to Basidiomycota. Ascomycota members included was Daldinia concentrica and Xylaria polymorpha.

Abstract: HIV-1 or Human Immuno Deficiency Virus-1 is the main causative agent of Acquired Immuno Deficiency Syndrome (AIDS). Human host infected with HIV - 1 extensively harbours many viral variants but very little is known about the difference in pattern^[17] of evolution of phylogenetic lineages of HIV-1 non recombinant, normal inter subtype recombinant and main two specific recombinant forms of HIV-1 i.e., Circulating Recombinant Forms (CRFs) and Unique Recombinant Forms (URFs). This study is mainly concerned with study of the difference in evolutionary lineages of non-recombinant and recombinant sequences of HIV-1 genome sequences and identification of geographically rich areas which has reported high degree of HIV-1 occurrence and variety. Total 1550 HIV-1 genome sequences were obtained from HIV Los Alamos Database. The sequences were aligned using MAFFT (Multiple Alignment using Fast Fourier Transform) web server tool. Alignment was carried out using 10 different set of alignment parameter values. After alignment the aligned file was used for constructing N-J phylogenetic tree using Clustal X2 tool. Phylogenetic analysis was performed keeping in mind the category to which the sequence belongs. Upon analysis it was observed that the clade containing the probable ancestor belongs remained constant in all cases of different alignment values. Non recombinant isolates, inter subtype recombinants, CRFs, URFs all followed different patterns of evolution. Non recombinant sequences were found geographically specific and subtype specific to some extent whereas, normal recombinants were subtype specific and less geographically specific. CRFs showed variation among the pattern of their evolution. At some instances the sequences occurred as sister taxa of non-recombinant or normal inter subtype recombinant sequences, while at some instances as sister taxa of other CRFs where they were geographically specific. Three CRFs existed as completely diverged sequences. URFs were four in number; two of them were Indian isolates of while other two were Japanese isolates. URFs were found to be totally geographically specific. Geography wise high rate of variation was observed in India and Japan as these two countries had sequences belonging to all of the above categories. Cameroon and South Africa have very large number isolates and a considerable amount of genetic variation among isolates but they lack URFs.

Abstract: Arsenic (As) is a metalloid that causes severe water pollution due to its extravagant toxicity. Ceriodaphnia dubia, a freshwater crustacean, was selected as a model system to evaluate the degree of time and dosage dependent acute toxicity caused by pentavalent As [As(V)]. C. dubia were collected from a natural pond and treated with different concentrations of As(V) for 24 hours and 48 hours. For both 24 hours and 48 hours treatment periods, the mortality rates were increased significantly ( P< 0.05) with increase in As(V) concentrations. Simultaneously, it was also observed that As(V) - induced mortality in C. dubia also depended on the time of exposure to the metalloid. We propose this model as a low-cost technique towards rapid screening of water quality in relation to As contamination.

Abstract: Increasing concentrations of chromium caused reduction in growth, chlorophyll contents and mineral mutrients of bhendhi. At increasing concentrations of chromium, all the attributes were found to be reduced. Chromium is one of the toxic elements discharging from tannery industry. The long disposal of tannery effluent to the agricultural land causes serious damages in the soil texture; reduce the growth of microorganisms and agricultural crops. Large areas of Vellore district of Tamilnadu was seriously affected by the tannery effluent irrigation to the agricultural land. The present study was conducted to identify the phytotoxic effect and physiological changes of Abelmoschus esculentus (L.) Moench under the treatment of different concentrations of chromium solutions (2.5, 5, 10, 25, 50, 75 and 100 mg/l). The result shows that there was a gradual reduction in the morphological parameters (root length, shoot length, fresh weight and dry weight). Similarly the photosynthetic pigments (Chlorophyll and carotenoid) and biochemical parameters such as protein, amino acid, and sugars were also gradually decreased with increasing concentrations of chromium.

Abstract: Plant glutathione peroxidases are an important class of enzymes which play key roles in the stress adaptability of plants both in context of biotic and abiotic stress pathways. They have been over the years much studied in animals since the catalytic residues are comprised of selenocysteine a variant amino acid which is ribosomally encoded with the help of an RNA structural element known as SECIS. Various workers over the years have shown that plant glutathione peroxidases play active roles in ROS sequestration, lipid hydroperoxidation as well as regulate glutathione levels. However, each plant has various patterns of glutathione peroxidase expression and action and in some plants certain isoforms have not been detected at all. This work focuses on the prediction and identification of single nucleotide polymorphisms (SNPs) and INDELs in the coding regions of plant glutathione peroxidases, with the help of a Bayesian based algorithm subsequently validated. A large number of informative sites were detected 279 of which had variant frequency of ≥ 50%. This data should be beneficial for future studies involving genetic manipulation and population based breeding experiments