Response of corn silage (Zea mays L.) to zinc fertilization on a sandy soil under field and outdoor container conditions

The purpose of the experiments was to evaluate zinc (zn) fertilization effect on growth,yield and yield components of corn silage grown on a sandy soil under field and outdoor container conditions. six rates of zn supply (0 or control; 1.5; 3; 5; 10 and 50 mg kg−1) were tested. they were split at three different times during the growing season: (i) 50% immediately after sowing,(ii) 25% at 4–5 leaf stage and (iii) 25% at 8–9 leaf stage. these zn rates were applied to the soil surface as a solution of zn sulfate (znso4·7h2o). zn deficiency symptoms appeared at an earlier stage (4–5 leaf stage) as white stripes between the midrib and the margin of leaves for a zn rate below or equal to 5 mg kg−1. severity of these symptoms manifested more in container than in field. for both experiments,zn supply induced a significant increase in stem height and leaf area. furthermore,in both experiments,control plants showed a notable delay in achieving anthesis,silking,pollination and kernels maturity. the maximum shoot dry weight at harvest was recorded with zn supply of 5 mg kg−1 in field experiment and 10 mg kg−1 in containers experiment. the shoot dry weight was especially linked to kernels dry weight. this latter was mainly enhanced through two compounds: 1000 kernels dry weight and pollination rate. on the other hand,outdoor container results can be used to help predict field plant responses to zn except for control treatment. © 2015 the authors