Histological components of Trifolium L. species related to digestive quality of forage

Abstract

The microscopic analysis of leaXet, petiole, stem and peduncle of 26 populations of 17 Trifolium species was carried out in order to examine their structural characteristics related to digestibility, to compare them between the populations of forage species and their wild relatives and to evaluate, from histological aspect, the potential of wild-growing species to be used as forages. Forage species had low proportion of the tissues composed of thick-walled cells and high proportion of the tissues composed of thin-walled cells in all examined plant parts. The reduction of the proportion of ligniWed xylem, sclerenchyma and sclerenchymatous interfascicular parenchyma, were suggested as basic selection criteria in breeding Trifolium species for improved digestibility. T. angulatum, T. medium and T. pannonicum proved to be very similar to the forage species in their histological composition, proportion of thick-walled and thin-walled cells and type of variation of the examined parameters. We believe that these species have some potential for use as forages in their own right, but aditional biochemical, physiological and morphological investigations should be conducted.

Digestibility-related histological attributes of vegetative organs of barrel medic (Medicago truncatula Gaertn.) cultivars

“…In earlier studies, genotypes with high digestibility showed lower surface density of lignified cell walls along the full stem length, compared to genotypes with low digestibility. Variations in tissue types and the site and type of lignification were also related to digestibility in other legume genera (e.g., Trifolium, Lathyrus), as well as in grasses Krstić et al, 2008;Zorić et al, 2011 a;. As lignified tissues also have an important role in providing mechanical support and plant resistance to various biotic and abiotic factors, manipulation of proportions of these tissues is limited (Buxton, Redfearn, 1997).…”

“…We consider structural investigations and understanding of biological basis of forage crops particularly important, as these factors directly affect digestibility and nutritive value of forages (Krstić et al, 2008). Rinne et al (2006) stated that a biological, rather than a chemical approach was needed in prediction of legume digestibility.…”

Modified Stereological Method for Analysis of Compound Leaves and an Example of Its Application

“…[11][12][13] Forage species have low proportion of the tissues comprised of thick-walled cells and high proportion of tissues with thin-walled cells, yielding higher digestibility. Reduction of the fiber content in vegetative organs of legume forages is one of the most important objectives in forage breeding programs for improving their digestibility, and was also suggested as a basic selection criterion in breeding of Trifolium L. species.…”

“…Reduction of the fiber content in vegetative organs of legume forages is one of the most important objectives in forage breeding programs for improving their digestibility, and was also suggested as a basic selection criterion in breeding of Trifolium L. species. 13,14 Bruinenberg et al 15 pointed out the importance of gaining knowledge about one of the significant factors that limits degradation -percentage of vascular tissue in the total leaf volume of forage crops. At the same time, structural characteristics of leaves, such as proportions of photosynthetic parenchyma and intercellular spaces, are extremely important for the transfer of carbon dioxide and process of photosynthesis.…”

“…13,[16][17][18] However, the demand for the more objective measurement of leaf anatomical parameters can be fully met by stereology. 10 It enables more precise measurement of the proportion of individual leaf tissues and their volume densities, which is necessary in understanding the relationships between the leaf anatomy, the rate of photosynthesis and forage digestibility.…”