Effects of defoliation on whole‐plant maize characteristics as forage and energy crop

Abstract

Hail affects yield and quality of maize crops, and consequences also depend on the growth stage at which the injury occurred. Whole‐plant maize (WPM) silage is often used within the same farm for cattle feeding and biogas production. The present study aimed to verify the effects of hail damage, simulated by artificial defoliation, on yield and chemical and nutritional features, as well as on biochemical methane potential (BMP) of maize forage. In a randomized block design with three replicates, four defoliation levels (0%, 33%, 66% and 100% of leaf area removal respectively) have been applied at either the V12 (12th leaf), R1 (silking) or R3 (milk) stages for two consecutive years. WPM yield, chemical and nutritional features, and BMP were measured. Dry‐matter (DM) yield per hectare was progressively reduced (p < 0.001) with increasing levels of defoliation and with application at V12 in comparison with R1 or R3 (1.26 vs. 1.39 and 1.46 kg ha−1 for V12 vs. R1 and R3; p < 0.003). Nutritive value and BMP per unit of product were less altered than dry‐matter yield per hectare by defoliation. Anticipating defoliation reduced net energy for lactation (5.26 vs. 5.46 MJ kg−1 DM for V12 and R3 respectively; p = 0.02). Total defoliation resulted in an accumulation of nitrates (NO3) compared to the other treatments (3.98 vs. 1.53 g NO3 kg−1 DM; p < 0.001). BMP was mainly reduced by early and complete defoliation. Equations were developed to estimate the effects of defoliation on yield, composition, and nutritive and energetic values of WPM.

Effect of removal of the upper stem of the ear (topping) and nitrogen application on maize for dual-purpose production of fodder and seed

“…Dry matter yield gradually decreased with increasing defoliation intensity and application at the twelve-leaf stage compared to silk or milking stages (Bani et al, 2019). Shesh et al (2019) reported that topping reduced maize seed yield, which is consistent with the results of the present study.…”

Monitoring of plant water uptake by measuring root dielectric properties on a fine timescale: diurnal changes and response to leaf excision

“…The weakening seasonality (s24) in the C R and G R time series along with increasing rELA was thought to be due to the removal of the most photosynthetically active young leaves. Similarly to the effect of dark-induced leaf senescence, severe defoliation levels also cause a limited supply and reallocation of photo-assimilates, resulting in restricted root growth [ 45 , 46 ]. This is why the increasing trend in the C R and G R measurement series became non-monotonic or even decreasing.…”

Is maize suitable for substitution planting in arsenic-contaminated farmlands?

“…Comparatively, maize cultivation is less economically beneficial than planting of other crops such as rice and vegetables, especially in the south of China. However, maize straw can be used as an energy source (Bani et al 2019) or feed for livestock, which could compensate the losses resulting from substitution planting to some extent. Nevertheless, a new way to implement the coordination of agricul-tural production and ensure soil remediation by As removal could be achieved by planting special maize cultivars such as cv.…”