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In today&rsquo, s agriculture, maize is considered to be one of the major feed, food and industrial crops. Cultivation of maize by inappropriate agricultural practices and on unsuitable sites is connected with specific risks of soil degradation, mainly due to water erosion of the soil. The aim of this study was to evaluate the yielding parameters, fodder quality and anti-erosion efficiency of different methods of conservation tillage for maize in two areas (Jev&iacute, čko&mdash, JEV and Skoup&yacute, &mdash, SKO) with different climate and soil conditions in the Czech Republic in the period 2016&ndash, 2018, using multivariate exploratory techniques such as principal component analysis (PCA) and factor analysis (FA). Four variants of soil tillage methods were analysed: Conventional Tillage (CT), two slightly different Strip-Till techniques (ST) and Direct Sowing (DS). The analysed parameters were: dry mass of the plants, height of the plants, starch content (SC), organic matter digestibility (OMD) and content of neutral detergent fibre (NDF), soil loss by erosion and surface runoff. The multivariate exploratory techniques PCA and FA significantly differed in two categories of techniques in both locations. The first category consists of soil conservation techniques (SCT): ST (JEV/SKO) and DS (JEV). These techniques are characterised by lower yields of dry mass, lower height of plants, forage quality equal to CT, but a high level of protection of the soil against erosion. The second category consists of CT (JEV and SKO) and partially of DS (SKO). These treatments are characterised by high dry mass production, higher plants, high forage quality, but a feeble capacity of protection of the soil against erosion. The results of the study confirm the presumption of the positive influence of introduction and application of new agronomical practices in the areas of interest and other areas with similar natural conditions in the sense of sustainable management for agricultural management of agricultural land for the conditions of the Czech Republic and therefore of Central and Eastern Europe. PCA and FA were used as an effective method for comprehensive evaluation of the use of STC in agricultural practice.

Sorghum is a forage species important in animal nutrition with an increased potential in the upcoming difficulties in agricultural practices in regard to climate change. Therefore, this paper describes its yield and nutritional parameters depending on growing conditions simulated on two locations (humid and fertile Obora, less fertile and dry Písky), two sowing dates (29. 5. and 25. 6.), and variety (11 varieties). Fresh matter yield was determined by weighing the sample on the field immediately after harvest, Dry matter yield and nutritional content were determined in laboratory by Weende analysis from dried and homogenized samples. Nutritional parameters measured were crude fibre, fat, nitrogen and ash content. Additionally, digestibility of organic as well as dry matter was determined. No significant differences in average fresh matter yield or dry matter yield were found between the two locations and sowing dates in general. There were significant differences among varieties, the highest yields were measured in KWS Zerberus (51.57 +- 3.76 t/ha of fresh matter yield, 15.98 +- 1.34 t/ha of dry matter yield, with higher values observed on Písky). Our data suggest, that sowing date does significantly affect fat content (higher in June sowing). Other nutritional parameters were also higher in sorghum sown in June, with the exception of ash. Nutritional composition of samples did not significantly differ variety to variety, however, there were differences in digestibility of the biomass. Organic matter digestibility was 70.58-85.67%, dry matter digestibility was 73.21-86.70%, with highest digestibility in DMS 45-480. Varieties with the highest importance to farmers in the area are KWS Zerberus, KWS Tarzan and KWS Kallisto (based on dry matter yield), and Triumfo BMR, Sweet Susana and DSM 45-480 (based on digestibility). Sorghum was able to perform well even on dry sandy soil with lower fertilization, which shows the high variability and suitability of sorghum in agricultural practice. info:eu-repo/semantics/openAccess

Catch crops mainly reduce soil erosion and leaching of nutrients as well as enrich the soil organic matter. The aim of this research is to evaluate the yields of catch crops of Sinapis alba, Phacelia tanacetifolia, Fagopyrum esculentum, Carthamus tinctorius and Secale cereale v. multicaule, and thus determine the possible applicability of catch crops in areas with high average annual temperature and low precipitation totals. The small-plot field experiment was performed on clay-loam gleyic fluvisol at the Field Experimental Station in Žabcice, Southern Moravia, Czech Republic, within the period of 2006-2014. The catch crops were set up after winter wheat in mid-August. The results have shown a statistically significant difference among different catch crops in yield of dry matter and even among years. The yield of catch crops is mainly dependent on a sufficient supply of water in the soil and the appropriate amount and distribution of rainfall over the growing season. Sinapis alba and Phacelia tanacetifolia regularly reached the highest yields. High yields were also achieved with Fagopyrum esculentum. Due to the method of crop rotation in the Czech Republic, with a predominance of Brassica napus var. napus, it is inappropriate to include Sinapis alba. It is the best to grow Phacelia tanacetifolia and even Fagopyrum esculentum, or a mixture thereof, depending on the use of catch crops.

The evaluation of the weed seedbank in the soil was carried out in 2013 and 2014 in the Žabčice vineyard. Within the frame of maintenance management, three methods of under-vine management were proposed: untreated control, chemical and mechanical method of weed management. 23 plant species were identified in the soil samples from the place below the grapevine. The obtained data were evaluated by the analysis of variance (ANOVA). Seeds of the species Amaranthus sp., Chenopodium album, Stellaria media, and Portulaca oleracea were the most common in all variants. Soil samples from the variant of mechanical weed management were the richest from the perspective of species. This variant also contained the smallest number of seeds per m2 of soil. info:eu-repo/semantics/openAccess

The aim of this study was to evaluate the heterogeneity of the incidence of individual weed species on a selected experimental field. This field was situated in the cadastre of the village Žabcice (South Moravian Region, Czech Republic). To evaluate the intensity of weed infestation, a field experiment was established. In 2011, altogether 33 weed species were identified in a stand of spring barley. In the next year, the total number of weeds in a stand of winter wheat was 22. Basing on results of the evaluation of infestation heterogeneity it was possible to detect the following trends: The first one concerned the incidence of significantly dominant species Chenopodium album and Veronica hederifolia in stands of spring barley and winter wheat, respectively. The second one expressed the incidence of the so-called sub-dominant species. Regarding the character of the incidence of these weed species it would be suitable to kill them by means of a targeted application of herbicides. Finally, the third trend concerned the incidence of that group of weeds that occurred in the major part of the experimental plot but in low numbers only. The abundance of these species was minimal and the total number of weed plants did not exceed the limit of 100 specimens. This group of weeds involved also those species that were markedly more frequent on plots situated closer to the margin of the experimental field. The targeted application of herbicides can be performed on plots with a lower level of weed infestation; another possibility, however, seems to be a targeted intervention that helps to control the incidence of a certain weed species and/or that is performed along the margin of the field where the different weed species are more frequent.

Stale castěji jsou v zemědělstvi využivany nove metody, jejichž hlavnim ukolem je racionalizace vstupů do zemědělske výroby. V oblasti regulace plevelů se nabizi možnost využiti metod založených na měřeni fluorescence chlorofylu ci odrazivosti zařeni. Využiti těchto metod může vest ke sniženi spotřeby pesticidů, cimž se sniži naklady na jejich pořizeni a sniži se riziko poskozeni životniho prostředi.V letech 2005-2007 byl na polni pokusne stanici Mendelovy zemědělske a lesnicke univerzity v Žabcicich založen maloparcelni polni pokus o ctyřech opakovanich a sedmi variantach v kukuřici zrnove, kde byla stanovovana ucinnost odstupňovaných davek herbicidů CALLISTO 480 SC + ATPLUS 463 a BASAGRAN SUPER na laskavec ohnutý (Amaranthus retroflexus). V pokusu bylo u herbicidu CALLISTO 480 SC + ATPLUS 463 využito davek (0,25-0,1875-0,125 l . ha-1) a u herbicidu BASAGRAN SUPER pak (2,0-1,5-1,0 l . ha-1). Aplikace herbicidů byla provedena zadovým motorovým postřikovacem SOLO 425 při aplikacnim tlaku 0,3 MPa a davce vody 300 l . ha-1 ve fazi ctvrteho listu kukuřice (laskavec - BBCH 13, tři prave listy). K měřeni ucinnosti herbicidů na laskavec ohnutý byl použit přistroj PS1meter, který je schopen měřit poskozeni fotosyntetickeho aparatu. Mira poskozeni byla měřena druhý, třeti, ctvrtý a patý den po aplikaci herbicidů. Na zavěr byl pokus sklizen maloparcelni sklizeci mlatickou SAMPO 2010 a sklizene zvažene vzorky byly přepocitany na výnos při 15% susině.Analýzou variance provedenou pro vsechny tři roky dohromady bylo zjistěno, že na naměřene hodnoty PS1 měl vysoce významný vliv herbicid (davka) a termin měřeni. Vliv rocniku na naměřene hodnoty PS1 nebyl statisticky průkazný. Nasledným testovanim pomoci Tukeyova testu (P = 0,95) byly zjistěny statisticky průkazne rozdily mezi kontrolou a ostatnimi variantami osetřenými odstupňovanými davkami herbicidů CALLISTO 480 SC + ATPLUS 463 a BASAGRAN SUPER. U herbicidu BASAGRAN SUPER nebyl zjistěn statisticky průkazný rozdil v naměřených hodnotach PS1 mezi jednotlivými sledovanými davkami. Z tohoto vyplýva, že vsechny sledovane davky měly dostatecnou ucinnost na laskavec ohnutý. Jako nevhodnějsi termin pro stanovovani ucinnosti tohoto herbicidu pomoci přistroje PS1 se jevi druhý den po aplikaci.U herbicidu CALLISTO 480 SC + ATPLUS 463 byl zjistěn statisticky průkazný rozdil v naměřených hodnotach PS1 mezi davkou 0,25 l . ha-1 (56,00) a davkou 0,1875 l . ha-1 (46,01). Při těchto hodnotach dochazi již k redukci fotosyntezy zhruba o 40 %. Ve třetim terminu měřeni (ctvrtý den po aplikaci herbicidu) bylo u vsech sledovaných davek herbicidů CALLISTO 480 SC + ATPLUS 463 ve vsech třech letech dosaženo hodnot převysujicich hodnotu 50, jež signalizuje velmi vysokou ucinnost na plevele. Při porovnani průměrných hodnot PS1 naměřených ctvrtý den po aplikaci nebyly zjistěny mezi jednotlivými lety ani davkami statisticky průkazne rozdily v hodnotach PS1. Proto lze tento termin doporucit u vsech sledovaných davek jako nejhodnějsi pro stanovovani ucinnosti na laskavec ohnutý ve fazi tři pravých listů.Při hodnoceni sklizně byl zjistěn statisticky významný vliv rocniku na výnos zrna přepocteneho na 15% vlhkost. Herbicidy ani jejich davky neměly statisticky významný vliv na výnos zrna. Neosetřena varianta (mechanicky odplevelovana) se ve výnosu statisticky průkazně nelisila od ostatnich variant. Nejvyssiho výnosu zrna přepocteneho na 15% vlhkost bylo dosaženo v sklizňovem roce 2006 (14,96 t . ha-1), v roce 2005 pak (13,52 t . ha-1) a nejnižsi výnos byl zaznamenan v roce 2007 pouze 9,97 t . ha-1. Nižsi výnos v roce 2007 byl zapřiciněn zejmena nedostatkem sražek během vegetace.

Chlorophyll fluorescence is a type of radiation emitted by plants as unused part of energy absorbed from sunlight. Its intensity depends on many stress factors, nutrition, weather conditions etc. Methods based on chlorophyll fluorescence measurement have potential to be perspective for the assessment of herbicide efficacy, phytotoxicity or stress influence. Two fluorometers (FluorCam and handy FluorPen) were used for measurements in laboratory experiments in 2007–2009. Herbicide Basagran super with active ingredient bentazone (480 g.l−1) was tested using a parameter called ‚Quantum yield of fluorescence‘ (QY) in three different doses: the registered dose 2.0 l.ha−1 (100%) and lower doses 1.5 l.ha−1 (75%) and 1.0 l.ha−1 (50%). Treated experimental plants of redroot pigweed (Amaranthus retroflexus L.) were measured in 0, 1, 2, 3, 6, 9 and 15 days after treatment and the results were compared with subjective assessment (estimation) and growth parameters. The obtained results showed that the effect of bentazone measured by both devices was statistically significantly different from untreated control. We can also detect herbicide effect earlier by QY measurement than by other methods. Different doses showed significant differences 15 days after treatment for dose 2.0 l.ha−1 in comparison with both reduced doses. The subjective assessment showed significant differences in all terms of measurement (1–15 days after application) except of the day of application. Regeneration of plants for which the youngest leaves were not treated by herbicide was observed for all doses. Difference of QY values between used devices was on average 0.119 (higher for FluorCam) but statistically insignificant.

The aim of the research work was to evaluate phytotoxicity of mesotrione in poppy (Papaver somniferum). The amount of spraying water (150, 300 and 450 l per hectare) was compared as well. In the end, the different growth stimulators (Atonik – 0.6 l . ha−1, Route – 0.8 l . ha−1) and the adjuvants (Atplus 463 – 0.5% solution, Silwet 77 – 0.1 l . ha−1) wre tested. Degree of phytotoxicity of individual va­riants was assessed by measuring chlorophyll fluorescence (parameter: maximum quantum yield of electron transport in photosystem II - QY) in 1st to 21st day after treatment. The results showed that the application of mesotrione caused phytotoxicity on poppy plants. The most significant phy­to­to­xi­ci­ty is evident at doses of 450 l spraying water per hectare. Addition of growth stimulators and adjuvants increases the phytotoxicity (decreases the value of QY) compared to the herbicide application itself. The mesotrione reduced the weight of dry plants by 15 % (150 l of spraying water), 1 % (300 l of spraying water) and 64 % (450 l of spraying water) compared to control variant.

The application of methods based on measurements of photosynthesis efficiency is now more and more popular and used not only for the evaluation of the efficiency of herbicides but also for the estimation of their phytotoxicity to the cultivated crop. These methods enable to determine also dif­fe­ren­ces in the sensitivity of cultivars and/or hybrids to individual herbicides. The advantage of these methods consists above all in the speed and accuracy of measuring.In a field experiment, the sensitivity of several selected grain maize hybrids (EDENSTAR, NK AROBASE, NK LUGAN, LG 33.30 and NK THERMO) to the herbicide CALLISTO 480 SC + ATPLUS 463 was tested for a period of three years. The sensitivity to a registered dose of 0.25 l . ha−1 + 0.5 % was measured by means of the apparatus PS1 meter, which could measure the reflected radiation. Measurements of sensitivity of hybrids were performed on the 2nd, 3rd, 4th, 5th and 8th day after the application of the tested herbicide, i.e. in the growing stage of the 3rd–5th leaf. Plant material was harvested using a small-plot combine harvester SAMPO 2010. Samples were weighed and converted to the yield with 15 % of moisture in grain DM.The obtained three-year results did not demonstrate differences in sensitivity of tested hybrids to the registered dose of the herbicide CALLISTO 480 SC + ATPLUS 463 (i.e. 0.25 l . ha−1 + 0,5 %). Recorded results indicated that for the majority of tested hybrids the most critical were the 4th and the 5th day after the application; on these days the average PS1 values were the highest at all. In years 2005 and 2007, none of the tested hybrids exceeded the limit value 15 (which indicated a certain decrease in the efficiency of photosynthesis). Although in 2006 three of tested hybrids showed a certain decrease in photosynthetic activity (i.e. EDENSTAR and NK AROBASE on the 3rd day and NK LUGAN on the 2nd–4th day after the application), no visual symptoms of damage of plants were found out. It could be concluded that the herbicide CALLISTO 480 SC + ATPLUS 463 (when applied in the registered dose of 0.25 l . ha−1 + 0.5 %) did not damage hybrids under study and did not show any statistically significant effect on the grain yield. This means that the manufacturer’s statement that this herbicide, if applied in the registered dose of 0.25 l . ha−1 + 0.5 %, is very tolerant to grain maize seedlings in the growth stage of 3–5 leafs, was correct. The most suitable date of measurements of differences in sensitivity to and/or potential phytotoxicity of the preparation CALLISTO 480 SC + ATPLUS 463 seemed to be the fourth day after the application because the measured average PS1 values were the highest in all hybrids under study. When evaluating the pooled three-year yields of grain (converted to 15% of moisture content) by means of variance analysis, a statistically significant effect of the year and the hybrid on the grain yield was found out. On the other hand, however, there was no statistically significant difference in the grain yield between control and the variant treated with the registered dose of the herbicide CALLISTO 480 SC + ATPLUS 463, i.e. 12.08 t . ha‑1 and 11.50 t . ha−1, respectively (grain moisture content 15%). When comparing pooled three-year yields of all hybrids under study, there were statistically significant differences between yields of the hybrid NK THERMO on the one hand and hybrids EDENSTAR and NK AROBASE on the other.