Corn Silage (Zea mays L.) Response to Zinc Foliar Spray Concentration When Grown on Sandy Soil

Abstract

The objective of this study is to identify an adequate zinc (Zn) foliar spray concentration which corrects Zn deficiency without disrupting other plant mineral contents, enhances plant growth, and thereby corn silage yield when grown on sandy soil. A field experiment was conducted using five Zn foliar spray concentrations (w/v): 0.03%, 0.07%, 0.10%, 0.14% and 0.18%. Zn sulfate (ZnSO 4 . 7H 2 O) was used as a source of Zn. Zn foliar application was realized at two growth stages (6-7 and 9-10 leaf stages). A treatment without Zn foliar spray was maintained as control. The results showed a quadratic response of corn silage towards Zn foliar spray concentrations, in which 0.09% was the optimum value for overcoming Zn deficiency. Such level increased shoot Zn concentration at harvest from 15 mg kg -1 to 21.8 mg kg -1 , didn't decrease plant mineral content below critical levels, enhanced plant growth and raised silage yield by 49.4% compared to control. On the other hand, Zn foliar spray concentration up to 0.10% induced visible leaf damage, growth inhibition and a decrease of 26% in silage yield compared to Zn foliar applications at 0.09%.

Effect of Zinc-Phosphorus Interaction on Corn Silage Grown on Sandy Soil

“…Furthermore, the biomass production response was particularly related to the kernel dry matter, which represents around 34% of the total shoot dry weight. This result agreed with our previous findings on corn responses to Zn soil supply [14,20] and to Zn foliar spray [19]. Concerning stem and leaves dry matter, they did not exhibit significant responses towards P and Zn supply.…”

“…Such results showed the depressing effect of high levels of P application without Zn supply on the pollination rate. The crucial role played by Zn in pollination was reported in previous studies conducted in the same sandy soil [14,19,20]. This role is particularly linked to the enhancement of male fertility [24].…”

“…However, all treatments had required shoot contents in Mn and Cu [26]. The depressed effect of Zn supply on Mn and Cu shoot content was reported with Zn foliar spray in corn silage grown in the same sandy soil [19]. Also, a significant diminishing effect from P application on K shoot content was recorded.…”

“…This significant response can be explained by the depressing effect of high P soil content in the reduction of Zn availability [1,10]. The beneficial effect of Zn in biomass production was reported in corn [14,19,20], in wheat [21], and in tomato [22]. Such an effect can be explained by the role of Zn in the metabolism of the β-carbonic anhydrase as a crucial enzyme involved in photosynthesis [23].…”

Effect of zinc application timing on yield formation by two types of maize cultivars

“…As a result, harvest indices of cobs and grain were higher in treatments with zinc. It is in agreement with the data reported by Drissi et al (2015).…”