Maize nuclear male sterility (ms) was discovered by Eyster in 1921, maize cytoplasmic male sterility (cms) was discovered independently in 1931-1933 by Hadjinov and Rhoades. Apart from ms and cms (based on ms genes and interactions of recessive rf alleles) there are other 2 distinct genetic methods of obtaining male sterile phenotypes: ts1 and ts2 mutants and reduced tassel phenotype (tl). The reduced tassels phenotypes, described abroad involves several defects, including damage of meristem (reduced height, reduced internode size, under-developed feminine inflorescence, reduced or missing tassel, modified leaves). The reduced tassel phenotype, studied and described in Moldova, represented only a reduction of tassels, with no other affection of the plant. The study involved sources originated from induced mutations and did not determined whether the phenotype can be propagated and perpetuated genetically. A study of this phenotype was conducted in 2010-2017 within the collection of inbred maize lines, originated from 81 distinct sources (mainly of hybrid origin). The reduced tassel phenotype was observed and described in 19 distinct sources, all of whom were at stage 8 and more of inbreeding and represent a large diversity of main morphological characters (maturation stages – FAO 170-490, kernel consistency and color, other characters). In order to determine the genetic origin, a thorough research was performed within one of identified sources. Reduced tassel phenotype was marked several times at stages VT-R1. Plants with reduced tassels were grouped in 6 phenotypic classes, were the first class (”grade 0”) was represented by plants with severely reduced tassels, sterile and the 6th class (”grade 5”) was represented by plants with normal tassels, completely fertile. The rest of classes contain plants with intermediary stages of reduced tassels, with different grades of male fertility. Phenotypically the plants with reduced tassels from all sources represent same morphological modifications: from normal and fertile tassel to severe reduction of tassel and its branches with complete absence of pollen. No other morphological modifications to other plant parts were observed. The result of this study is the identification of 19 distinct sources of reduced tassel phenotype can serve a solid base for further study and identification of precise genetic origin. The sources were selected from inbred lines with valuable ameliorative characters, with no defects.