Optimization of the Proliferation of an Ancient Pear Tree Cultivar ('Decana d'inverno') through the Use of Neem Oil.

culture, ensuring rapid multiplication and production of plant material under aseptic conditions, represents an excellent tool for conservation of tree species biodiversity and can be used for the conservation, among others, of endangered and rare crops. Among the L. cultivars that have been abandoned over the years due to changed cultivation requirements, but which are still used today in breeding programs, there is the 'Decana d'inverno'. Pear is generally considered a recalcitrant species for propagation due to weak multiplication rate, hyperhydricity, and susceptibility to phenolic oxidation. Therefore, the use of natural substances like neem oil (although little explored) represents one of the options to improve the plant's tissue culture. In this context, the aim of the present work was to evaluate the effect of adding neem oil (0.1 and 0.5 m L L) to the growth substrate in order to optimise the culture of the ancient pear tree cultivar 'Decana d'inverno'. The neem oil addition resulted in an increase in the number of shoots produced especially at both concentrations used. On the contrary, an increase in length of proliferated shoots was observed only with the addition of 0.1 mL L. The neem oil addition did not affect the explants viability, fresh and dry weights. Therefore, the present study demonstrated for the first time the possibility of using neem oil to optimise the culture of an ancient pear tree cultivar.