N. Petrovska*, V. Valkova
Maize Research Institute, 5835 Knezha, Bulgaria
(Manuscript received 10 June 2016; accepted for publication 28 September 2016)
Abstract. During the period 2012 – 2014, a second cycle of recurrent selection of early flowering in a synthetic maize population “Exotic-07” was conducted and finished on the experimental field of Maize Research institute – Knezha. The experiments are carried out by a block method, on a test plot of 10 m2, with three replications, and the respective for the region agricultural equipment. Twenty-three progeny from the first and second cycle, the source and improved exotic maize populations, as well as their testcrosses with the lines ХМ 4416 and PAU 1617 are tested. A phenotypic cycle assumes a leading position in terms of dates of plant silking as the forms of the earliest flowering are used as pollen in the population. The selected early flowering forms are sown for inbreeding and forming an improved maize population. As a direct result of the work of improvement, progeny with a period of days until silking averagely shorter with 5 days and grainmoistureloweredby1.1%areobtained.Theaimofthisstudyistopointoutinbredlineswithashortervegetativeperiodandusethemasparental forms for obtaining high-yielding mid-late maize hybrids.