The Efficacy of Three Species of Trichodew for the control of Basal Stem Rot in Oil Palm Seedlings

This study evaluated the potential of three Trichoderma species, namely T. harzianum t (isolate BIO T32), T. longibrachiatum (BIO T28) and T. virens (BIO T128) for the control of Ganoderma boninense (EGB Ol), the causal pathogen of basal stem rot (BSR) of oil palms in nursery trials. Besides their spore production and antagonistic properties, h s study also investigated the growth response of each of the species towards a wide range of temperature and pH conditions. All three species exhibited particular strengths in the growth parameters studied but BIO T32 exhibited consistent and relatively good antagonistic properties and was used as the main inoculant in 'nursery trials against G. boninense. The type and size of wood block were found to influence the success and consistency of the inocula in establishing disease during artificial infection of seedlings. Very low infectivity rates were acheved when inoculum blocks were half to a quarter of the standard 6 x 6 x 12 cm; this size was found to give consistent infection rates leading to approximately 85% mortality. In nursery trials, seedlings treated with a single inoculum of T. lzarzianum (TI) gave the lowest and most significant disease severity index (DSI) of 28.34. The conidial drench was stopped at week 14 and the first sign of disease was only observed on week 20. The uninfected and untreated control seedlings gave a DSI of 0 where as, the infected, untreated controls gave a DSI of 86.87. Soils under treatment using a single (TI), two mixed (T2) and three mixed (T3) inocula showed an increase in spore count based on colony forming units (cfu) starting from two weeks after application. When the soil drench was tenninated at week 14, the spore count was peak on the 18&, 1 4 a~nd 1 0 ~ week for TI, T2 and T3 treatments respectively. Spore counts of BIO T32 were not significantly different on the upper (5 cm) and deeper (15 cm) layer of the treated soils. This study found that when T. lzarzianum (BTO T32) was used as a single inoculum, it f gave the most significant and effective performance as a biological control agent. This was only followed by a mixture of T. hurzianum and T. longibrachiatum. Lastly, the use of a combination of three Trichoderma species were found to give the poorest disease control, giving a DSI that was not statistically different from the infected, untreated control experiment

Analysis of composite moving beams using higher order shear deformation theory

A Composite beam moving longitudinally over its supports is analyzed based on a higher-order shear deformation theory. The dynamic behavior of the beam is carried out using the finite element method. The formulation is based on a variational principle. The essential constraints are applied via Lagrange multipliers. This method is effective for the moving beam problem where the relative support locations change with time and therefore the supports do not fall exactly at the nodes. An initially deformed overhang beam moving over two simple supports is used for the analysis. The first flexural mode shape of the beam is used as the initial shape of the beam. The finite element equations of motion are then solved using time integration methods such as Newmark\u27s method and Wilson Theta method. The results are presented in terms of time history of tip deflections. The performance of the higher-order shear deformation model is compared with that of the first-order shear deformation theory and Classical laminate plate theory. The response in all the cases exhibits a beat-like phenomenon due to the interplay of the axial frequency and the transverse natural frequencies. In all the cases considered, the axial motion causes a magnification in the transverse deflection by about 40%

Present status of molluscan fisheries and culture in India

India has extensive molluscan resources along both the coasts, in the numerous islands, bays, back waters and estuaries and also in the seas around the Sub-continent

On the Gammaridean amphipoda of the Gulf of Mannar, with special reference to those of the pearl and chank beds

During the underwater survey of the pearl and chank beds off Tuticorin carried out by 'Scuba' diving, a number of amphipods were also seen amongst various material collected from the sea bottom. These amphipods were studied in detail. incorporating the amphipods of the pearl banks of Ceylon described by Walker (1904) a complete list with synonymies of all the reported species of amphipods from the Gulf of Mannar, together with the description and sketches of species wherever found necessary, has been given in this account

Processing, preservation and marketing

Shellfishes are highly perishable and this irrespectiye of their market potential is a major hurdle to the development of the industry. Soon after spawning the meat will be thin and not very tast

Present status of mussel culture in India

The technique of raft culture of mussels developed and practised in Spain and followed by other European nations is a stimulating example of the higher efficiency of resource use, technically feasible to achieve several-fold increase over the level of natural bed production

Technology of edible oyster culture

In oyster culture there are two important major aspects (1) production of seed and (2) growing the seeds to marketable size.This paper deals with the latter aspect of oyster culture

Studies on the growth of the wedge clam, Donax (Latona) cuneatus Linnaeus

Of the several species of wedge clams of the family Donacidce that occur on the east and west coasts of India in the surf-beaten sands, Donax scortum to some and Donax cuneatus to a very large extent are valued as food by many people. In the Palk Bay, ail along the beach from Pillaimadam shore <Long. 79° 5' and Lat. 9° 17') to Attankarai (Long. 79° 0' and Lat. 9° 21'), a distance of about seven miles, the receding tides reveal Donax cuneatus in abundance. It forms the food of a large number of fishermen along the coast when the sea is rough and the general fishery conditions poor. It is usually fished only during such off-seasons and is not sold in the open, market. The clam meat is cooked whole or made into a paste and treated with condiments in the preparation of curries. Dead shells of these clams, washed ashore, are collected by the womenfolk for preparing lime. However, at present there is no regular fishery of these clams for food or any organised lime burning industry, with the result that this valuable resource is wasted without being much utilized. The present investigation was taken up with a view to exploring the possibilities of exploitation of this resource of food without any undue damage to the beds