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The germination percentage of teak seed is generally very poor due to its higher percentage of empty seed and poor seed viability. The viable seeds exhibit protracted germination behaviour due to their inherent seed dormancy and other physiochemical characteristics. Hence establishing a teak nursery for largescale plantation activities is a challenging task. This study was undertaken to study the effect of ageing on in vitro true seed and in vivo drupe germination and its dormancy mechanism in teak. Fresh, one-year and two-year stored drupes were used to represent different levels of ageing. Under in vivo conditions, poor drupe germination was observed in fresh drupes (3%) and germination percentage was increased when the drupes were subjected to ageing for one year (17%) or two years (32%). When true seeds separated from fresh drupes and germinated under in vitro conditions, enhanced germination (58.3%) was observed. Biochemical analysis showed that indole-3- acetic acid, indole butyric acid, abscisic acid and coumarin are not present in fresh, one year and two-year-old true seeds. The gibberellic acid was increased with an increase in ageing, but the GA3 did not influence the germination percent under in vitro conditions. Scanning electron microscope (SEM) image of fresh teak true seed showed that embryo tip was shrivelled, whereas one and two-year-old true seed embryo tip bulged; this was confirmed that one and two-year-old true seed embryos were matured and satisfied the after-ripening requirement. Nursery studies revealed that one and two-year-old drupes recorded the highest germination compared to fresh drupes.

Major parts of agricultural lands in arid and semi-arid regions of India are affected by soil salinity and waterlogging in canal command area and outside. Waterlogging is caused by a rising water table and poor drainage conditions.  Stress due to waterlogging and salinity are serious to plants in all stages from seed germination to active growth and maturity. Unmanaged affected agricultural lands turn into low productive marshlands in the long run. Physical provision of surface or sub-surface drainage structures can rescue in such a situation. Yet, high skill and investment are required in the installation and maintenance of such structures. Alternatively, biodrainage method has been evolved as an effective method recently world over. In biodrainage, plants are raised over a larger area, which can transpire and remove an enormous amount of water from the soil. Plants having adequate adaptive traits and tolerance mechanisms are desirable to mitigate waterlogging and salinity. Biodrainage is suitable in rainfed and irrigated conditions. Planting of right plant species in optimum population and geometry decides the efficiency of biodrainage. Further, combining biodrainage with the conventional drainage can improve land and water productivity. Eucalyptus is the most suitable tree species for biodrainage as it has well performed in versatile environments. It possesses appreciable tolerance to salinity, sodicity and waterlogged conditions of the soil.  Fast-growing with a straight trunk, deep rooting ability, low shading effect and high transpiration capacity are promising characteristics of this tree.  Prominent woody species like Acacia nilotica, Dalbergia sissoo, Hardwickia binata can also be grown for high profit.

In-vivo and in-vitro germination trials were done on the teak (Tectona grandis) seeds collected from a farmland and forest plantation in Tamil Nadu. Under in-vivo pot culture condition very low germination percent of drupes was observed in seed collected from plantation(Top slip) and famrland (Kumulur). When true seeds isolated from the drupes were grown under in vitro condition in half strength MS medium, the germination percent was significantly increased up to 63.3 per cent. True seed germination among two teak sources showed the presence of mechanical dormancy which was a major limiting factor for poor drupe germination for deployment of superior genetic materials.

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The prominent issue faced by the farmers of Cauvery Delta regionin Tamil Nadu particularly Tiruchirapalli District is the lack of timely release of water for rice nursery preparation and transplanting. Hence wet seeding of rice is recommended for timely cultivation. On the other hand, sodic nature of the soil warrants rice cultivation only. Therefore, the present investigation was carried out to study the different soil and crop management practices on alleviating sodicity stress and improving rice (variety ADT 3) productivity under water-scarce conditions. The experiment was laid in a split plot design with six mainplots,including rice wet seeding, daincha (Sesbania aculeata) application as green manure, anti-oxidant microbial consortia (AOMC) spray and four sub-plots with graded levels of NPK based on soil test values with three replication. Results showed that the daincha incorporation @ 6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 125 % soil test based NPK had significantly increased thechlorophyll content, SPAD values, proline content and grain and straw yields which remained on par with daincha incorporation @ 6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 100 % soil test based NPK.Significantly lower ESP at 5% level and higher phosphatase activity in soil was also recorded by daincha incorporation @ 6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 125 % and 100 % soil test based NPK. Gross return, net return and B:C ratio were also higher in the plot, which received daincha incorporation @6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 100 % soil test based NPK. The present study reveals that the inclusion of ectophytic microbial population spray in rice plants and the management practices helps the crop to tolerate the sodicity stress under water-scarce condition by maintaining required physiological functions like proline synthesis and enzyme activities etc which need to be further explored at the genotypic level.

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