Radek Filipčík

Nitrogen fertilization does not affect micronutrient uptake in grain maize (Zea mays L.)

Abstract Due to continuous single nitrogen fertilization, we hypothesized a built-up deficiency of micronutrients in crops that would limit plant growth and crop quality. In 2-year field experiments using urea-N fertilized grain maize (Zea mays L.), hybrid KWS 2376 at 0, 120 and 240 kg N ha−1 crop uptake of Zn, Mn, Cu and Fe was studied at DC 32, DC 61 and in the grain harvested. Micronutrient contents at DC 32 stage – 1st node (aboveground phytomass) and DC 61 – flowering (ear leaf) were all at levels indicative of adequate micronutrient supply to the crop. At both sampling occasions the Fe:Zn and Fe:Mn ratios were adequate implying that Fe did not inhibit the uptake of Zn and Mn. The application of nitrogen increased the Fe content at the 1st sampling in both years; in the second year the same was also the case for the Zn content. Nitrogen nutrition increased the contents of Mn and Fe at the 2nd sampling only in year 2; in the other treatments no changes were observed in the micronutrient contents. Micronutrient correlations in the grain were discovered between Zn and Mn contents and between Fe and Mn contents. In the second year the highest N-rate significantly increased the Fe and Zn content of the grain compared with the lower rates of nitrogen fertilization. Grain yields were not affected by the rate of nitrogen and ranged between 13.65 and 14.34 t ha−1 (1st year) and between 13.68 and 14.18 t ha−1 (2nd year). Nitrogen fertilization did not reduce the content of micronutrients in the plant or grain of maize. It is evident that the continuous single use of N fertilization so far has not resulted in a micronutrient deficiency of the plants limiting the nutrient density of the grain or reducing its quality.

Effect of combined nitrogen and sulphur fertilization on yield and qualitative parameters of Camelina sativa [L.] Crtz. (false flax)

Abstract Camelina (Camelina sativa (L.) Crtz., false flax) is described as a species requiring fewer inputs than other oilseed crops thus making it an interesting alternative in sustainable cropping systems. As information on the combined effects of nitrogen and sulphur on camelina yield and quality parameters is meagre, a pot fertilization experiment was carried out with nitrogen applied as NH4NO3 at three increasing rates equivalent to a range from 63 up to 127 kg ha−1. These treatments were combined with sulphur additions applied as (NH4)2SO4 to achieve a soil sulphate content of 25 or 45 mg kg−1, respectively (equivalent to 75 and 135 kg S ha−1). The medium and high nitrogen rates combined with the low sulphur fertilization level increased the number of branches per plant compared with the lowest nitrogen fertilization at the same sulphur rate. Camelina seed yield increased with increasing nitrogen doses at the same low sulphur level, whereas straw yield increased only at the highest rate of nitrogen. Thousand-seed mass increased at the highest nitrogen dose and with the low sulphur application rate. In addition, the increase in nitrogen fertilization reduced seed oil content from 39.8% to 37.1%. A highly negative correlation was observed between oil and protein content of seeds. Nitrogen fertilization increased total oil yield and total protein yield. Differences in crop parameters between the sulphur treatments were not significant statistically, although the higher sulphur treatment tended to increase seed yield as well as oil and protein content compared with the low sulphur treatment. Thus, the combined application of N and S as mineral fertilizers is only recommended when growing camelina on sulphur-deficient soils if the aim is to achieve both high oil and protein production.

The Effect of Low and High Cowshed Temperatures on the Behaviour and Milk Performance of Czech Fleckvieh Cows

Abstract A group of 98 Czech Fleckvieh cows (one section) was observed over the period of one year with the aim to determine the variation in their milk performance and behaviour at different cowshed temperatures. Behaviour and milk yield were recorded once a week (on the same day) at 10:00. Periods of 8 weeks with the highest temperature (hot period - H) and of 8 weeks with the lowest temperature (cold period - L) were then compared. The cows were housed in one section (1/4 of the total capacity) of the free-stall cubicle shed and where the cubicles were distributed into three rows. Row A (32 cubicles) was close to the feeding plateau, row B (33 cubicles) was in the centre and row C (38 cubicles) was peripheral, close to the side wall. The cowshed temperature was monitored on a daily basis and the mean temperature was 23.2°C in the hot period and -1.7°C in the cold period, relative humidity 60.2% (H) and 74.6% (L), and THI 69.4 (H) and 33.4 (L). The behaviour of the cows was recorded 1568 times, showing them mostly lying down (1037) or standing (531). The cows tended to prefer lying down on their left sides (594 observations) as opposed to their right sides (443). Row A was favoured by the cows (418) and row B was the least popular (377). The cows produced significantly more milk in H period than in L period (0.3 kg per day). The cows lying down were older (3.18 lactations) than the standing cows (2.99 lactations) and they tended to produce more milk per day (by 0.6 kg) but the difference was found to be insignificant. The cows lying resting on their left side produced more milk per day (0.9 kg) and were older (0.02 lactations). The cows in row C were the youngest (2.94 lactations) and the cows in row B were in the last days in milk (144.1 days).