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A greenhouse study was conducted to test the effects of low herbicide dose exposure on different crops measuring visible damages, plant height, leaf area, and dry matter. Seven crops were tested: lettuce (Lactuca sativa L.) cv. Novosadska majska maslena, oil pumpkin (Cucurbita maxima Duch) cv. Olivija, oilseed rape (Brassica napus L.) cv. NS Ras, pepper (Capsicum annuum L.) cv. Kurtovska kapija, soybean (Glycine max (L.) Merr) cv. ZP Laura, sunflower (Helianthus annuus L.) cv. NS Kruna, and tomato (Solanum lycopersicum L.) cv. Dunavski Rubin. Herbicide dicamba in the range of 0.14 to 1 155.6 g a.i. (active ingredient)/ha inhibited biomass, height, leaf area, and visual injury of all crops, while glyphosate doses from 0.48 to 3 840 g a.i./ha also reduced the growth of all tested species. A rate of 116 g a.i./ha mesotrione was needed to reach 80% visual injury in oilseed rape, while the same effects on lettuce only required 1.8 g a.i./ha of mesotrione. Tomato and oil pumpkin were also sensitive to low mesotrione doses, where only 1.3 g and 0.5 g a.i./ha of mesotrione was needed for 80% of biomass reduction, respectively. Lettuce was the most sensitive crop of all tested species; biomass was reduced by 80% by dicamba, glyphosate, mesotrione, and nicosulfuron at the low rates of 33 g a.i./ha, 19 g a.i./ha, 1.25 g a.i./ha, and 2.7 g a.i./ha, respectively. Among all herbicides, visible injuries were detected in dicamba at the lowest rates. Soybean was the most tolerant of glyphosate, mesotrione, and nicosulfuron. Based on the available literature and obtained results, herbicide off-target movement must be mitigated to maximise herbicide efficacy and decrease the negative influence on susceptible plants and the environment.

Crop density is a means that controls grain yield establishment. This study was focused on evaluating the effect of four crop densities (CD1—50,125 plants ha−1, CD2—59,523 plants ha−1, CD3—69,686 plants ha−1, and CD4—79,365 plants ha−1) on yield components, grain yield, sustainable yield index (SYI), and rain use efficiency (RUE) of the maize hybrids ZP 500, NS 5010, and AS 534 during 2016–2018. In 2017, due to unfavorable meteorological conditions, ear length, number of grains per ear, grain weight per ear, 1000-grain weight, grain yield, SYI, and RUE were low compared to 2016 and 2018. The hybrid NS 5010 had the lowest ear length, number of grains per ear, grain weight per ear, 1000-grain weight, grain yield, and SYI. Increasing crop density significantly decreased yield components and increased grain yield, SYI, and RUE. The lowest ear length was recorded in treatments CD3 and CD4, the lowest number of grains per ear, grain weight per ear, and 1000-grain weight in treatment CD4. However, the highest grain yield, SYI, and RUE were recorded in the CD4 treatment because the number of plants per unit area is an essential determinant of the final grain yield.

The main aim of this research was to study the effect of two sowing times (early and late) on Fusarium and fumonisin contamination and some yield component traits of two maize hybrids from the FAO maturity groups 500 (ZP 560) and 600 (ZP 666) within a two-year growing season (2016–2017). F. verticillioides and F. subglutinans have been identified as Fusarium ear rot (FER) pathogens and potential producers of B-type fumonisins (FBs), with F. verticillioides as the predominant Fusarium species in both years. The incidence of F. verticillioides and FB levels were affected by sowing time and maize hybridity. With early sowing and the mid-maturity hybrid ZP 560, F. verticillioides and FB contamination were lower than with late sowing and the late-maturity hybrid ZP 666. Yield parameters also differed significantly between sowing time and maize hybrid treatments. Early sowing increased ear length (EL), number of grains per ear (NGE), grain weight per ear (GWE), and grain yield per hectare (GY). The late-maturity hybrid ZP 666 had higher yield component traits and GY than the mid-maturity hybrid ZP 560. EL, GWE, thousand-grain weight (TGW), and GY were affected by year. Interactions between sowing times and maize hybrids were highly significant (p ≤ 0.01) for FB level, GWE, and GY. The obtained results indicate the importance of applying early sowing to achieve high maize grain yields with lower contamination by F. verticillioides and FBs. Although mid-maturity hybrid ZP 560 and late-maturity hybrid ZP 666 showed significant differences in terms of levels of F. verticillioides and FB contamination, both were susceptible to F. verticillioides, with high FB levels. These results should be useful to breeders of maize hybrids to create genotypes more resistant to these fungal contaminants.