The proteome responses to heat stress have not been well understood. In this study, alfalfa (Medicago sativa L. cv. Huaiyin) seedlings were exposed to 25 °C (control) and 40 °C (heat stress) in growth chambers, and leaves were collected at 24, 48 and 72 h after treatment, respectively. The morphological, physiological and proteomic processes were negatively affected under heat stress. Proteins ...

Seeds of alfalfa (Medicago sativa) and white clover (Trifolium repens) were primed in 3 priming solutions [2% NaCl, 2% KNO3 and 300 g/L polyethylene glycol (PEG)] for 2 days at 20°C and their subsequent germination compared with that of untreated seed. Four replications of 50 seeds for germination and 25 seeds for emergence were arranged in a 2-factor factorial completely randomised design. All...

Alfalfa (Medicago sativa L.), a perennial and outcrossing species, is a widely planted forage legume for hay, pasture and silage throughout the world. Currently, alfalfa breeding relies on recurrent phenotypic selection, but alternatives incorporating molecular marker assisted breeding could enhance genetic gain per unit time and per unit cost, and accelerate alfalfa improvement. Many major qua...

What happens when one nation cultivates a transgenic crop variety but neighboring nations do not? Using alfalfa as a case study, we argue that the potential for international transgene flow is substantial, and therefore, the need for international cooperation in regulatory decisions concerning transgenic crops is imperative. Alfalfa (Medicago sativa, L.) is the major forage crop in North Americ...

Down-regulation of the enzyme hydroxycinnamoyl CoA: shikimate hydroxycinnamoyl transferase (HCT) in thale cress (Arabidopsis thaliana) and alfalfa (Medicago sativa) leads to strongly reduced lignin levels, reduced recalcitrance of cell walls to sugar release, but severe stunting of the plants. Levels of the stress hormone salicylic acid (SA) are inversely proportional to lignin levels and growt...

The production of somatic embryos in alfalfa (Medicago sativa L., cv Regen S) is increased 5- to 10-fold by alanine and proline. However, utilization of nitrogen for synthesis of protein from alanine, proline, glutamate, and glycine is not qualitatively different, even though the latter two amino acids do not increase somatic embryo formation. These determinations were made by (15)N labeling wi...

Disease outbreaks due to the consumption of legume seedlings contaminated with human enteric bacterial pathogens like Escherichia coli O157:H7 and Salmonella enterica are reported every year. Besides contaminations occurring during food processing, pathogens present on the surface or interior of plant tissues are also responsible for such outbreaks. In the present study, surface and internal co...

Megachile rotundata (F.), an adventive, gregarious, cavity-nesting, leaf cutting bee, is used throughout North America for the pollination of alfalfa, Medicago sativa L., seed crops. We examined the inßuence of various postcocooning (prewintering) temperature regimes on development, survival, emergence time, and longevity in both nondiapausing and diapausing forms of this species. Diapausing ma...

Ractopamine is a beta adrenergic agonist used as a growth promoter in swine, cattle and turkeys. To test whether ractopamine has the potential to accumulate in plants grown in contaminated soil, a greenhouse study was conducted with alfalfa (Medicago sativa) and wheat (Triticum aestivum) grown in two soils having different concentrations of organic matter (1.3% and 2.1%), amended with 0, 0.5, a...

Traces of luteolin, an important rhizobial nod gene inducer in Rhizobium meliloti, are released by alfalfa (Medicago sativa L.) seeds, but most luteolin in the seed exudate is conjugated as luteolin-7-O-glucoside (L7G). Processes affecting the production of luteolin from L7G in seed exudate are poorly understood. Results from this study establish that (a) seed coats are the primary source of fl...