The influence of plant cutting on grain yield traits in maize

Abstract

In this research an influence of the strong source restriction meaning cutting off the whole plants at the first internodes 5 (5DAPt), 10 (10DAPt) and 15 (15DAPt) days after pollination on grain yield and its corresponding traits in maize were tested. Control represented plants harvested at full maturity. Four inbred lines were used, two historical ones (Mo17 and B73) and two commercial ZP inbreds (ZPL and ZPB). The experiment was conducted at Zemun Polje, Serbia, in 2014 and 2015. The trait of particular importance was the number of kernels per ear and its average values were 37.73 at 5DAPt, 115.14 at 10DAPt and 175.20 at 15DAPt, being sufficient for planting next generation of breeding. According to the results obtained, ZPL represented an improved Lancaster line over Mo17 regarding drought tolerance, that could not be stated for ZPB over B73. Hybrid among these two lines is drought tolerant due to heterosis (epistatic effects) or dominant origin of ZPLs good response to drought stress. Values for seed set and eventually for grain yield per plant were 0.00 for line B73 at 5DAPt in 2015. An improved breeding scheme for increased drought tolerance could be proposed, namely self-pollination of border plants on high density sown selfing progenies or dihaploid (DH) lines, cutting off selfed plants at 15 DAP and evaluating their kernel properties. Openpollinated progeny would serve to estimate other important traits for selection. From the chosen progenies kernels of selfed and cut-off plants should be used for the next generation of breeding.