The study examined photosynthetic efficiency of two barley landraces (cvs. Arabi Abiad and Arabi Aswad) through a prompt fluorescence technique under influence of 14 different abiotic stress factors. The difference in the behavior of photosynthetic parameters under the same stress factor in-between cv. Arabi Abiad and cv. Arabi Aswad indicated different mechanisms of tolerance and strategies for the conversion of light energy into chemical energy for both the landraces. This study confirmed the suitability of some chlorophyll fluorescence parameters as reliable biomarkers for screening the plants at the level of photosynthetic apparatus.

Animal performance can be improved by overseeding legumes into grass swards, but little is known concerning consumption of various legumes over time. This study compared selection of various legumes to grass and weeds, and gathered information helpful in configuring grazing systems. Over two grazing seasons, esophageally fistulated steers (Bos taurus) sampled replicated pasture systems of; (i) orchardgrass (Dactylis glomerata L.) and red clover (Trifolium pratense L.) (OG‐RC), (ii) orchardgrass and birdsfoot trefoil (Lotus corniculatus L.) (OG‐BFT), and (iii) orchardgrass alone (OG) as spring and fall pasture near Columbia, MO. Steers also sampled the same treatments as summer hay regrowth, except that alfalfa [Medicago sativa L.] replaced birdsfoot trefoil in Treatment ii (OGALF). Grass dominated swards and steer diets, but selectivity ratios (SR) indicated no preferential selection for grass by steers. Dietary amounts of birdsfoot trefoil and red clover on pasture, and red clover and alfalfa on hay regrowth were similar, although availability of red clover was generally less than the other legumes. Thus, steers selected red clover to a greater extent over birdsfoot trefoil or alfalfa early in pasture and hay regrowth, and avoided both species during the fall. Average SR values indicate selectivity for weed species was least on OG‐RC followed by OG‐BFT, OG, and OG‐ALF. Diets from grass‐legume systems contained similar amounts of weeds and legumes, but weed proportion increased with time.

Extensive management is one of the methods used in the conservation of fen meadows. The aim of the study was to characterize grassland communities grazed by Konik horses in the Biebrza National Park and to assess the influence of short-term grazing on the sward. During a 3-year period, phytosociological studies, measurements of the sward cover and height, as well as an assessment of the botanical composition of meadows were conducted in places grazed and excluded from grazing. The grasslands were mowed once a year at the turn of July and August, with the exception of mid-forest meadows. The area studied was dominated by communities of the Molinion alliance. Horses kept at a very low stocking rate reduced the height and cover of the sward. In the short-term, weather conditions, especially the duration of floods, had an even greater impact on the species composition of communities than grazing. Therefore, in order to protect the Molinia meadows, apart from extensive mowing, it is necessary to maintain appropriate habitat conditions, especially in terms of controlling the moisture, and conduct its regular monitoring.

Knowledge of botanical and chemical composition of herbage consumed by grazing livestock is essential in understanding animal performance and improving pasture and animal management. Esophageal fistula samples are considered to best represent cattle (Bos spp.) diets, but current microscopic methods used to determine botanical composition are time consuming, expensive, and may be subject to large operator error. Pinitol (1‐D‐3‐O‐methyl‐chiro‐inositol) has been found unique to the leguminosae family and accurate in determining alfalfa (Medicago sativa L.) percentage in greenhousegrown alfalfa‐tall fescue (Festuca arundinacea Schreb.) mixtures (R2 = 0.99). Its utility in estimating the legume composition of esophageally collected grass‐legume samples was compared to that of two widely used microscopic techniques. No significant differences were found between microscopic methods in pasture or hay aftermath of any treatments or dates. Sensitivity analysis showed no differences in the two methods related to their ability to detect dietary legume concentration changes in esophageal samples. Pinitol estimates of legume content were less (P<0.05) than those from microscopic estimates taken from orchardgrass (Dactylis glomerata L.) + legume [red clover (Trifolium pratense L..), birdsfoot trefoil (Lotus sp.), or alfalfa] pasture and hay aftermath, but not from nearly pure orchardgrass. The three methods provided similar estimates late in the grazing season when all values were low. With few exceptions the pinitol method underestimated legume composition of esophageal samples. In a separate experiment, the pinitol content of alfalfa, red clover, and birdsfoot trefoil extrusa after mastication and salivation was lower than that of unfed samples, suggesting that leaching may have been partially responsible for low estimates of legume composition by the pinitol method

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