Influence of salinity on germination and early seedling root growth traits of alfalfa (Medicago sativa L.) landraces collected in Southern Algerian oases

When normally harvested for hay, the basal portion of alfalfa (Medicago sativa L.) stems is low in forage quality. This study was conducted to determine whether genetic variation for in vitro digestible dry matter (IVDDM) and crude protein (CP) concentration of stems of perennial Medicago spp. could be identified and whether morphological and chemical traits were associated with variation in these characteristics of stems. The lower six nodes and internodes of stems and total herbage from 64 Plant Introduction (PI) accessions and five cultivars of field-grown plants were harvested twice when most plants were at the early seed-pod stage of maturity. Several morphological and growth traits were measured, and both stems and total herbage were evaluated for IVDDM and CP concentration. Covariant analysis was used to adjust in IVDDM and CP concentration of stems for differences in plant maturity. Significant variation for IVDDM and CP concentration in stems existed among the cultivars and among the accessions. Some accessions had significantly higher stem IVDDM or CP concentration than control cultivars. The M. sativa accession, PI 440496, had the fourth highest stem IVDDM and third highest stem CP, with concentrations of 374 and 79 g kg−1, respectively. The number of ridges on stems (stem shape) was significantly correlated with stem IVDDM and CP concentration with average correlation coefficients of 0.30 and 0.35, respectively. Cell-wall concentration and lignin concentration per unit cell wall of stems were both negatively correlated with stem IVDDM and CP concentration. Selection for improved nutritive value of stems may have potential for improving the nutritive value of alfalfa herbage.Key words: Alfalfa, forage quality, crude protein, in vitro digestibility, Medicago sativa L.

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Using small tubes to measure root elongation of newly germinated alfalfa seedlings in relation to moisture

Canadian Journal of Plant Science ◽

10.4141/cjps94-045 ◽

1994 ◽

Vol 74 (2) ◽

pp. 215-219 ◽

Cited By ~ 1

Author(s):

John Waddington ◽

Marvin C. Snoop

Keyword(s):

Medicago Sativa ◽

Root Elongation ◽

Moisture Stress ◽

Moisture Loss ◽

Seedling Root ◽

Root Elongation Rate ◽

Glass Tubes ◽

Polyvinyl Chloride Plastic ◽

Medicago Sativa L ◽

Better Than

A method of growing newly germinated seedlings in small tubes was developed to enable the study of early root elongation. Three newly germinated alfalfa (Medicago sativa L.) seeds were placed in tubes of various diameters and volumes filled with sand at several moisture tensions, and the tubes were sealed to prevent moisture loss. For the first 4 d, roots elongated at approximately 8 mm d−1 in polyvinyl chloride plastic tubes holding 60 mL of sand with a moisture tension of 100 kPa or less. After the initial 4 d, root elongation continued at a slower rate, and branch roots developed before termination of the experiments at 12 d after germination. At a moisture tension of 300 kPa, root elongation was markedly less than at 100 kPa, and was zero at moisture tensions of 500 kPa or greater. In round-bottom glass tubes, root elongation rate was significantly slower in a sand volume of 23 mL than in 65 mL, and there was evidence of slower seedling development as the diameter of the tubes was reduced from 20 to 15 mm. Wax plus masking tape or nylon tape were equally effective in sealing the sides of tubes formed from the two halves of a plastic pipe previously cut lengthwise. A plastic cap plus wax was significantly better than plastic film for sealing the bottom ends of plastic tubes. Neither aeration nor replacement of water with a dilute nutrient solution had an effect on root elongation of young seedlings. Key words: Alfalfa, seedling, root elongation, moisture stress, Medicago sativa

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Maize seedling performance as a potential index for drought tolerance

Archives of Biological Sciences ◽

10.2298/abs170504036k ◽

2018 ◽

Vol 70 (1) ◽

pp. 167-177

Author(s):

Natalija Kravic ◽

Sukalovic Hadzi-Taskovic ◽

Vojka Babic ◽

Jelena Srdic ◽

Jelena Mesarovic ◽

...

Keyword(s):

Drought Tolerance ◽

Osmotic Stress ◽

Root Growth ◽

Grain Yield ◽

Maize Seedling ◽

Proline Content ◽

Seedling Root ◽

Early Seedling ◽

Positive Correlations ◽

Adult Plants

Twenty-six maize landraces were tested in order to evaluate maize seedling performance as an index for drought tolerance in adult plants. Samples were subjected to polyethylene glycol-induced osmotic stress at the early seedling stage. Grain yield was obtained in field experiments under well-watered (OC) and a combination of drought and high plant density (HD) conditions. Osmotic stress caused a reduction in seedling growth (length, fresh and dry weight), and increase in the shoot and in particular the root proline contents in the majority of landraces, and variations in root peroxidase (POD) activity. Genotypes displaying more pronounced root growth reduction and higher proline contents exhibited decreased POD activity under osmotic stress. Direct positive correlations between the proline content and growth inhibition, and between the proline and soluble protein content were established. Correlations between the changes in POD activity and growth parameters were significant and positive, and significant but negative with the changes in the proline content. In the field, water stress led to a reduction in grain yield in all of the tested landraces. Correlations between grain yield from both experimental sets (OC and HD) and osmotic-induced changes in seedling root growth were negative, which was opposite to the highly significant and positive correlations between the changes in the seedling root proline content and yield. Also, genotypes with the highest seedling root proline content increase under osmotic stress, exhibited the highest stress tolerance index (STI) based on grain yield achieved under both field conditions. Our results indicate that lower changes in POD activity and especially an increased proline content after exposure to osmotic stress during the early seedling stage could be considered as useful indices to facilitate selection efficiency for drought tolerance in adult plants.

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Allelopathic Effects of Sorghum Halepense (L.) Pers. and Avena Sterilis L. Water Extracts on Early Seedling Growth of Portulacca Oleracea L. and Medicago Sativa L

International Journal of Medical Science ◽

10.14445/23939117/ijms-v5i10p103 ◽

2018 ◽

Vol 5 (10) ◽

pp. 7-12

Author(s):

Braah Othman ◽

◽

Dina Haddad ◽

Samir Tabbache

Keyword(s):

Medicago Sativa ◽

Seedling Growth ◽

Sorghum Halepense ◽

Avena Sterilis ◽

Water Extracts ◽

Early Seedling Growth ◽

Early Seedling ◽

Medicago Sativa L ◽

Allelopathic Effects

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Phosphorus seed coatings for pasture species. I. Effect of source and rate of phosphorus on emergence and early growth of phalaris (Phalaris aquatica L.) and lucerne (Medicago sativa L.)

Australian Journal of Agricultural Research ◽

10.1071/ar9880437 ◽

1988 ◽

Vol 39 (3) ◽

pp. 437 ◽

Cited By ~ 8

Author(s):

JM Scott ◽

GJ Blair

Keyword(s):

Medicago Sativa ◽

P Uptake ◽

Early Growth ◽

Phalaris Aquatica ◽

Early Seedling Growth ◽

P Content ◽

Early Seedling ◽

Medicago Sativa L ◽

Germinating Seeds ◽

P Sources

Seed coatings containing phosphorus (P) can be an effective way of promoting early seedling growth in P-deficient soil, but there is insufficient information available on the P sources and rates which are both safe to germinating seeds and effective in supplying P. A growth chamber experiment was undertaken to study the effect on the emergence and early growth of phalaris (Phalaris aquatica L.) and lucerne (Medicago sativa L.) of seed coatings containing one of three P sources (mono-[MCP], di-[DCP], or tricalcium phosphate [TCP]) at three rates (0.625, 1.25 or 2.5 mg P seed-1). The emergence of lucerne was markedly delayed (as measured by fitted Mitscherlich functions) by increasing rates of MCP, whilst that of phalaris was only slightly delayed. DCP and TCP had only slight effects on the emergence of both species. Leaf number (at 27 days after sowing [d.a.s.]), dry matter yield and P content of shoots of both species (at 35 d.a.s.) were increased by all P sources. With phalaris, MCP was approximately four times as effective per unit of P as DCP, which in turn was approximately four times as effective as TCP, whereas, with lucerne, MCP was twice as effective as DCP, which in turn was twice as effective as TCP. The results show that whilst emergence was most affected by soluble P sources at high rates, these same sources were most effective in promoting early P uptake per unit of P applied.

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Alkalinity and salinity tolerance during seed germination and early seedling stages of three alfalfa (Medicago sativa L.) cultivars

Legume Research - An International Journal ◽

10.18805/lr.v0i0.8401 ◽

2017 ◽

Author(s):

Huihui Zhang ◽

Xin Li ◽

Xu Nan ◽

Guangyu Sun ◽

Minglong Sun ◽

...

Keyword(s):

Seed Germination ◽

Medicago Sativa ◽

Salinity Tolerance ◽

Germination Percentage ◽

Fresh Weight ◽

Experimental Conditions ◽

Low Salinity ◽

Early Seedling ◽

Medicago Sativa L ◽

Radical Length

The germination of halophytes in saline-alkali substrates is a useful criterion for selection tolerant alfalfa (Medicago sativa L.) cultivars. The experimental conditions consisted of five levels of salinity (24, 48, 72, 96 and 120 mM) and four pH levels (7, 8, 9 and 10). The results showed that under saline conditions, the germination percentage (Gp), plumule length (Pl) and radical length (Rl) also decreased with increasing concentration. However, under low or moderate saline conditions, Pl and fresh weight decreased sharply but Rl was the longest at 48 and 72 mM and pH 7.1, which indicated that low salinity may promote radical growth appreciably. Salinity and alkalinity stresses had synergetic effects on Gp, Ge and Gi but not on Pl, Rl and fresh weight. The results confirmed Gp, Gi and Ge are important indices for assessing germinated energy of alfalfa in salinity-alkalinity soils. Moreover, three alfalfa cultivars tested were relatively tolerant of salinity and alkalinity and Stockpile was the most tolerant cultivar in the present experiment.

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