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Subsoil manuring is a practice that involves placing high rates of organic amendments in bands at the base of rip-lines that extend down into the subsoil to a depth of 30–40cm, in order to ameliorate poorly structured clay subsoils. The objective of this study was to determine whether the increases in crop yield from this practice, which occurred at one site in the high-rainfall zone in Victoria from 2005 to 2007, would occur at other sites and in other seasons in south-western Victoria. On-farm field experiments were therefore carried out at three sites in south-western Victoria between 2009 and 2012 to measure the yield responses to subsoil manuring. The study found that subsoil manuring with poultry litter resulted in consistent and recurring increases in estimated grain yield at these sites, with responses occurring with consecutive crops. Increases in estimated grain yield continued for 4 years, with average increases in hand-harvested yield of 3.5 t ha–1 for wheat, 1.6 t ha–1 for canola and 2.3 t ha–1 for faba beans. The estimated increases in grain yield were frequently associated with the increased extraction of deep subsoil water after anthesis. A treatment involving deep-banded nitrogen (N) and phosphorus (P) fertilisers and additional in-crop N, which matched the N and P in the poultry litter, yielded less than the full rate of subsoil manuring in seven of the eight site-years. This suggests that yield responses from subsoil manuring were not solely due to the release of N and P from the deep-banded poultry litter.

A pre-nursery system fur raising coconut seedlings was compared with the conventional nursery. The two major refinements introduced in the pre-nursery system are the slicing of seed nuts and transplanting of sprouted seed nuts from pre-nursery beds to nurserv beds, soon after sprouting. The rate of sprouting in the Pre-nursery system was significantly superior. At the end of 20 weeks 76% of the seednuts in the pre-nursery had sprouted as compared to 67% in the conventional nursery. However, the number of plantable seedlings produced was not signifivantly different. The cost of production of seedlings in the pre-nursery system was over 50% more than that of the conventional nursery. It appears that slicing the seednut facilitates sprouting but transplanting sprouted seednuts from the pre-nursery caused a setback to the development of the seedlinjr*.

Coconut is so important, not only economically but also socially, that it was described as ‘one of Nature's greatest gifts to man’ by Burkill (1966). Despite the inherent constraints to the breeding of palm species, important progress in coconut improvement has been obtained using standard breeding techniques. A continuous effort to search for new genetic material within Sri Lanka and to conserve valuable material threatened with erosion is in progress. Somatic embryogenesis, which is the only method of vegetative propagation, has been achieved on a limited scale but consistent plant regeneration is yet to be accomplished. Zygotic embryo rescue has been exploited to propagate an indigenous ‘Makapuno ’ type coconut. Development of DNA markers in order to exploit the existing variability in coconut germplasm to its maximum potential is being explored.