Showing papers on "Sativum published in 1996"

Effects of green manures on verticillium wilt of potato

Abstract: Two field studies were conducted to investigate the effects of green manure treatments on Verticillium wilt of potato (cv. Russet Burbank) caused by Verticillium dahliae. Each study involved the use of a sudangrass (Sorghum vulgare var. sudanense 'Monarch') green manure treatment and a fallow treatment for either 2 or 3 years prior to growing potato. In addition to sudangrass, comparisons also were made with several green manure treatments, including Austrian winter pea (Pisum sativum 'Austrian winter'), two cultivars of rape (Brassica napus var. napus 'Dwarf Essex' and 'Bridger'), rye (Secale cereale), oat (Avena sativa 'Monida'), and corn (Zea mays 'Jubilee'). Verticillium wilt of potato was best controlled after green manure treatments of either sudangrass or corn ; after these treatments, yields were increased above all other treatments. Wilt was most severe when potato followed the fallow treatment and intermediate following rape, Austrian winter pea, oat, and rye. Wilt incidence was positively correlated with V. dahliae colonization in apical stems but was not significantly related to other pathogens (Pratylenchus neglectus, Colletotrichum coccodes, Rhizoctonia solani Ag-3) or to effects of green manure treatments on preplant nutritional effects of N, P, or K.

Flow cytometric and Feulgen densitometric analysis of genome size variation in Pisum.

Abstract: A DAPI and ethidium bromide flow cytometric and Feulgen densitometric analysis of genome size variation in Pisum was conducted. The material included 38 accessions of P. sativum of widely different geographic origin and altogether 14 samples of P. elatius, P. abyssinicum, P. humile and P. fulvum. The relative genome size values obtained with the three staining methods were strongly correlated. No evidence for genome size variation was found among P. sativum cultivars. In particular, certain Italian cultivars, for which strongly deviating C-values have been reported, proved to be invariant. The only occasion when ambiguous evidence for marginal genome size variation was found was when all 38 accessions taxonomically affiliated with P. sativum were considered. Pisum abyssinicum and P. fulvum differed from P. sativum by about 1.066-and 1.070-fold, respectively; 1 accession of P. humile differed by 1.089-fold, and 2 of P. elatius by 1.122- and 1.195-fold, respectively (ethidiumbromide comparison), while the other accessions of these taxa were not different from P. sativum. This variation may indicate taxonomic inhomogeneity and demands further investigation. Cultivated P. sativum has long been suspected of not being constant with respect to genome size. As shown here, these findings were not based on genuine differences, but rather were technical in origin.

Linkage mapping of quantitative trait loci controlling seed weight in pea (Pisum sativum L.)

Abstract: Quantitative trait loci (QTLs) affecting seed weight in pea (Pisum sativum L.) were mapped using two populations, a field-grown F2 progeny of a cross between two cultivated types (‘Primo’ and ‘OSU442-15’) and glasshouse-grown single-seed-descent recombinant inbred lines (RILs) from a wide cross between a P. sativum ssp. sativum line (‘Slow’) and a P. sativum ssp. humile accession (‘JI1794’). Linkage maps for these crosses consisted of 199 and 235 markers, respectively. QTLs for seed weight in the ‘Primo’ x ‘OSU442-15’ cross were identified by interval mapping, bulked segregant analysis, and selective genotyping. Four QTLs were identified in this cross, demonstrating linkage to four intervals on three linkage groups. QTLs for seed weight in the ‘JI1794’ x ‘Slow’ cross were identified by single-marker analyses. Linkage were demonstrated to four intervals on three linkage groups plus three unlinked loci. In the two crosses, only one common genomic region was identified as containing seed-weight QTLs. Seed-weight QTLs mapped to the same region of linkage group III in both crosses. Conserved linkage relationships were demonstrated for pea, mungbean (Vigna radiata L.), and cowpea (V. unguiculata L.) genomic regions containing seed-weight QTLs by mapping RFLP loci from the Vigna maps in the ‘Primo’ x ‘OSU442-15’ and ‘JI1794’ x ‘Slow’ crosses.

Growth, yield and neurotoxin (ODAP) concentration of three Lathyrus species in Mediterranean-type environments of western Australia

Abstract: The growth, phenology, grain yield and neurotoxin (ODAP) content of Lathyrus sativus, L. cicera and L. ochrus were compared with a locally adapted field pea (Pisum sativum L.) to examine their potential as grain legumes in Western Australian farming systems. About 17 lines of each species were obtained from ICARDA, Syria, and grown at 3 agro-climatically different sites. In general, the 3 species were later flowering than field pea, especially L. cicera and L. ochrus; however, L. sativus was the last species to mature. The best Lathyrus lines produced biomass near flowering similar to field pea. At the most favourable site, grain yields were up to 1.6, 2.6 and 1.7 t/ha for L. sativus, L. cicera and L. ochrus respectively, compared with a field pea grain yield of 3.1 t/ha. There was considerable genotype and environmental variation in ODAP concentration in the seed. On average, the ODAP concentration of L. ochrus (6.58 mg/g) was about twice that of L. sativus, and L. cicera had the lowest ODAP concentration (1.31 mg/g). Given that Lathyrus spp. have not had the same breeding effort as field pea and other grain legumes in Australia, these results encourage further selection or breeding. In the shor-tseasoned, mediterranean-type environment of Western Australia, harvest indices and grain yields could be improved with early flowering. Low ODAP concentration should also be sought.

Fungicidal control of powdery mildew in field pea

Abstract: The efficacy of sulfur (Kumulus S) and myclobutanil (Nova 40W) fungicides for control of powdery mildew (Erysiphe pisi Syd) in field pea (Pisum sativum L.) was investigated in field trials at two locations in Manitoba in 1994 and 1995. Both fungicides were effective in reducing disease seventy and increasing seed yield and seed weight of the susceptible cultivar Radley. Fungicide treatments were economically beneficial when disease pressure was high. Key words: Field pea, Pisum sativum L., powdery mildew, Erysiphe pisi Syd., sulfur, myclobutanil

Multiple viral determinants affect seed transmission of pea seedborne mosaic virus in Pisum sativum

Abstract: Two pea seedborne mosaic potyvirus (PSbMV) isolates, P-1 DPD1 (P-1), which is highly seed-transmitted, and P-4 NY (P-4), which is rarely seed-transmitted, and chimeras between P-1 and P-4 were analysed to map the viral genetic determinants of seed transmission. Infectivity of chimeric viruses was evaluated by inoculating Pisum sativum with RNA transcribed in vitro from recombinant full-length cDNA clones. The chimeric viruses that were used demonstrated that a genomic segment encoding the 49 kDa protease and putative RNA polymerase was responsible for symptom induction. Attempts to determine transmission of the chimeric viruses in P. sativum cultivars known to transmit P-1 at high frequencies showed that seed transmission is a quantitative character influenced by multiple viral determinants. Seed transmission frequency did not correlate with accumulation of virus in vegetative tissue. The 5′ 2·5 kb of the 10 kb PSbMV genome had a major influence on the seed transmission frequency and was analysed further. This showed that, while the helper-component protease was a major determinant of seed transmission, the potyviral P1-protease exerted no measurable influence.

The use of RAPD technique for the identification and classification of Pisum sativum L. genotypes

Abstract: The genomic DNAs of 42 Pisum sativum genotypes, representing four wild and cultivated subspecies were used as templates in RAPD reactions. Amplification with eight decamer primers generated 149 polymorphic products. Genetic similarities of RAPD profiles were estimated via a coefficient of Jaccard and then the data were processed by cluster analysis (UPGMA). Each genotype was clearly identified and separated from the others. Our results show that RAPD technology is a rapid, precise and sensitive technique for identification of pea genotypes. However, the phylogenetic relationships within the Pisum sativum, which we tested by bootstrap analysis (Wagner parsimony), must be interpreted with caution.

Root-hair infection and nodulation of four grain legumes as affected by the form and the application time of nitrogen fertilizer

Abstract: The effects of application of combined nitrogen fertilizer (ammonium nitrate or urea) on root-hair infection and nodulation of four grain legumes were studied. Young roots of each legume were inoculated with their compatible rhizobia. The application of the two forms of combined N either at the early stages of plant growth and/or at the time of nodule formation depressed root-hair curling, infection and nodulation. Infection of hairs on the primary roots was more sensitive to the N fertilizer than hair infection of secondary roots in bothVicia faba andPisum sativum. The nodule number and total fresh mass of the four legumes were drastically affected by fertilizer application. The combined N added both at early and at later stages significantly reduced the nodulation ofV. faba, Phaseolus vulgaris andVigna sinensis. The inhibitory effect of urea on nodulation ofP. sativum was only observed when the fertilizer was applied at the late stages of plant growth. It is concluded that, although the nodulation of the four legumes was suppressed by combined N, the initial events ofRhizobium-legume symbiosis (infection of roots and nodule initiation) are more sensitive to combined N than the stages after nodule formation.

Biological and molecular properties of a pathotype P-1 and a pathotype P-4 isolate of pea seed-borne mosaic virus.

Abstract: Two isolates of pea seed-borne mosaic potyvirus, DPD1 and NY, were identified as pathotypes P-1 and P-4, respectively, by their infectivity on Pisum sativum L. lines homozygous for the recessive resistance genes sbm-1 and sbm-4. The two isolates differed in several biological characteristics. DPD1 induced transient vein clearing, downward rolling of leaflets and internode shortening on P. sativum, whereas NY only caused a slight growth reduction. DPD1 moved systemically in Chenopodium quinoa whereas NY was restricted to inoculated leaves. DPD1 was frequently transmitted by seeds whereas NY was rarely seed-transmitted: 24% and 0.3%, respectively, in P. sativum ‘549’. Both DPD1 and NY were transmitted by aphids (Myzus persicae), though a DAG triplet was not present in the N terminus of the coat protein. The nucleotide sequence and deduced amino acid sequence of NY were determined and compared to the corresponding sequences of DPD1.

Chemical composition of the seed oil of Coriandrum sativum L. from Cuba.

Abstract: The essential oil obtained by hydrodistillation from the dried seeds of Coriandrum sativum L growing in Cuba was investigated by GC and GC/MS Thirty-five compounds (969%) were identified, of which linalool alone accounted for 5457% of the oil

Distribution of Ten Enzymes of Carbon Metabolism in Pea (Pisum sativum) Chloroplasts

Abstract: Immunolocalization indicates that the largest part of the P-glycerate kinase and sedoheptulose bisphosphatase in the pea (Pisum sativum L.) chloroplast, about half of the glyceraldehyde-3-P dehydrogenase and P-ribulokinase, and a smaller fraction of the triose-P isomerase, aldolase, and carbonic anhydrase are thylakoid-bound. There are probably metabolic advantages to be gained from this distribution. Rubisco and Rubisco activase appear to be restricted to the stroma.

Effect of timing and intensity of drought on the growth and yield of field peas (Pisum sativum L.)

Abstract: The response of field peas (Pisum sativum L.) to timing and intensity of drought was determined in an experiment in a mobile rainshelter, which excluded rainfall during growth of the crop. Twelve irrigation treatments subjected the crops to drought of varying duration at different stages during plant growth. Before and after the drought, the crops were fully irrigated. Pea seed yield decreased linearly as the maximum potential soil moisture deficit (Dpmax) experienced during the growth of the crop increased from 49 to 323 mm. The timing of Dpmax did not affect the decline in pea seed yield, but did affect the total dry matter (DM) produced by the crop. If Dpmax occurred before flowering, radiation interception and total DM yield were reduced more than if Dpmax occurred after flowering. However, this total yield reduction was completely offset by an increase in individual pea weight and consequently an increased harvest index. Pea seed yield was closely related to pod number per unit area, which w...

Potamogeton pectinatus Is Constitutively Incapable of Synthesizing Ethylene and Lacks 1-Aminocyclopropane-1-Carboxylic Acid Oxidase.

Abstract: A highly sensitive laser-driven photoacoustic detector responsive to [less than or equal to]2.1 nmol m-3 ethylene (50 parts per trillion [v/v]) was used for ethylene analysis. Dark-grown plants of Potamogeton pectinatus L. growing from small tubers made no ethylene. Exposure of shoots to white light, wounding, submergence in water followed by desubmergence, partial oxygen shortage, indole acetic acid, or carbon dioxide failed to induce ethylene production, although clear effects were observed in Pisum sativum L. Some ethylene was released after applying high concentrations of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC; 10 mol m-3) to P. pectinatus, but the amount was trivial compared with that released by P. sativum. More endogenous ACC was found in P. pectinatus than in P. sativum. Considerable ACC oxidase activity was present in tissue extracts of P. sativum. However, no ACC oxidase activity was found in P. pectinatus, indicating that this is where ethylene production is arrested.

Genome size in wild Pisum species.

Abstract: Genome size was measured in 75 samples of the wild pea species Pisum abyssinicum, P. elatius, P. fulvum and P. humile by ethidium-bromide (EB) flow cytometry (internal standard: Triticum monococcum) and Feulgen densitometry (internal standard: Pisum sativum ‘Kleine Rheinlanderin’). Total variation of EB-DNA between samples covered 97.7% to 114.9% of the P. sativum value, and Feulgen DNA values were strongly correlated with EB-DNA values (r=0.9317, P < 0.001). Only P. fulvum was homogeneous in genome size (108.9% of P. sativum). Wide variation was observed between samples in P. abyssinicum (100.9–109.7%), P. elatius (97.7–114.9%) and P. humile (98.3–111.1% of P. sativum). In view of the world-wide genome size constancy in P. sativum, the present data are interpreted to show that the pea taxa with variable genome size are genetically inhomogeneous and that the current classification is not sufficient to describe the biological species groups adequately.

Nitrate alters the flavonoid profile and nodulation in pea (Pisum sativum L.)

Abstract: A rhizosphere application of NO inf3 sup- and/or naringenin affected the Pisum sativum — Rhizobium leguminosarum biovar viciae symbiosis. NO inf3 sup- (5 mM) lowered while naringenin raised the nodulation status (nodule numbers and weight) and nodule efficiency (C2H2 reduction activity). However, the inhibitory effect of NO inf3 sup- was to some extent alleviated when applied in combination with naringenin. The plant biomass was increased by the application of NO inf3 sup- and naringenin, either alone or in combination, while a higher root: shoot ratio was observed only in the naringenin-treated plants. Root flavonoids are known to regulate the expression of nod genes; their high-performance liquid chromatography profile was influenced in different ways by NO inf3 sup- and naringenin.

Genetics of tolerance to high concentrations of soil boron in peas (Pisum sativum L.)

Abstract: The inheritance of tolerance to high concentrations of soil boron in pea (Pisum sativum L.) was studied in five cross combinations and their reciprocals. Segregation patterns for boron response in F2 populations and F3 derived families were established by visual assessment of leaf damage. The segregation ratios were explained in terms of two major gene loci interacting in an additive manner with incomplete dominance at each locus. Evaluation of selected tolerant and susceptible families indicated that tolerant families contained a significantly lower concentration of boron in shoots than susceptible families.

Nodulation of field-grown Pisum sativum and Vicia faba: Competitiveness of inoculant strains of Rhizobium leguminosarum bv. viciae determined by an indirect, competitive ELISA method

Abstract: An indirect, competitive, enzyme-linked immunosorbent assay (ELISA) was developed to indentify strains (SU391, SU303, WSM937, NZP5472) of Rhizobium leguminosarum bv. viciae in the nodules of Pisum sativum and Vicia faba and to study the effect of legume species and indigenous R. l. viciae on the nodulating-competitiveness of these strains, applied as seed inoculants. The study involved field-grown crops at Avondale and Merredin in Western Australia and Wagga Wagga in New South Wales. A multivariate statistical procedure was used to determine an optimal classification rule by which nodule isolates were allocated as an inoculant strain or indigenous strain. The legume significantly affected the proportion of nodules formed by inoculant strains at Merredin. Strains (SU303, WSM937 and NZP5472) with V. faba cv. Fiord were very competitive with indigenous rhizobia, forming 53–92% of the nodules. In comparison, inoculant strains on P. sativum at Merredin were found in 500 g−1 soil, the nodulating-competitiveness of inoculant strains applied to faba bean. No inoculant strain was remarkably better than another at competing with indigenous R. l. viciae. We conclude that seed inoculation often may be more successful with V. faba than P. sativum, which is fortuitous because indigenous R. l. viciae are more likely to be less efficient for N2 fixation with faba bean (cv. Fiord) than with pea. The relatively poor success with inoculation of P. sativum suggests the need to determine its efficiency for N2 fixation with indigenous R. l. viciae, and to ensure novel cultivars are effectively nodulated by these rhizobia. The poor representation of inoculant strains in nodules on faba bean grown in soils with very large numbers of soil-borne R. l. viciae may severely reduce its productivity. Moreover, we propose that seed inoculation may not achieve a solution to this problem.

Peronospora viciae on Pisum sativum: morphology of asexual and sexual reproductive structures.

Abstract: Asexual and sexual reproductive structures of Peronospora viciae, which causes downy mildew of pea (Pisum sativum), were studied using low temperature scanning electron microscopy. Sporangiophores ...

Effect of sublethal dosages of 2,4-D on annual broadleaf crops

Abstract: Field experiments were conducted from 1992 to 1994 in southern Manitoba to investigate the tolerance of buckwheat (Fagopyrum esculentum Moench.), canola (Brassica napus L.), field pea (Pisum sativum L.), lentil (Lens culinaris Medik.) and sunflower (Helianthus annuus L.) to sublethal dosages of 2,4-D; 2,4-D amine was applied at 0,9.5, 18.9, 37.8, 75.2 and 151.2 g a.i. ha−1 2 wk after crop emergence when buckwheat and canola were in the two- to three-leaf stage, lentil and field pea had a vine length of 10 cm, and sunflower was in the four- to six-leaf stage. Application rates corresponded to 0, 1.5, 3, 6, 12 and 24% of the low recommended field rate of 2 4-D (630 g a.i. ha−1). Field pea yields were unaffected by 2,4-D dosages tested in any year. Increasing dosage of 2,4-D reduced lentil and canola yields in two of three years, while buckwheat yields were reduced in one year only. Sunflower yields were severely reduced in all three years by 2,4-D. At 151.2 g a.i. ha−1, predicted yield losses were 43% for b...

Effect of cadmium on the distribution of micronutrients in Lactuca spp., maize and pea plants

Abstract: The effect of different doses of Cd on the uptake and distribution of micronutrients in several species of Lactuca, (Lactuca sativa cv. Winter yellow; Lactuca serriola cv. Hortelano; Lactuca serriola cv. Pancalieri), two cultivars of Zea mays (cvs. Dakalb XL 72 AA and Dekalb Paolo) and two cultivars of Pisum sativum (cvs. Argona and Waverplus) is studied. Plants exposed to Cd concentrations ranging from 0.1 to 15 mg Cd 1-1 showed more accumulation of Cd in root than in shoot (from 7 to 15 times higher in root). Growth and visual symptoms showed that Pisum cultivars were those affected the most. The content of Mn in plant tissues was reduced consistently under Cd treatments. Moreover, the relative concentration of Mn was higher in shoot than in root, which indicates a sort of redistribution among tissues. Fe uptake was also reduced or not by the exposure to Cd in the nutrient solution depending on the species. Moreover, the analysis of other micronutrients (Cu and Zn) revealed that no consistent alteration in their content was achieved.

Study of the variation in the somatic embryogenesis ability of some pea lines (Pisum sativum L. and Pisum arvense L.)

Abstract: Thirty lines of pea were tested in vitro to evaluate their ability to produce somatic embryos. Three distinct genotypic classes were detected (strong, medium and weak). The best responses were obtained in Pisum sativum. Abnormal somatic embryos and secondary embryogenesis seem to constitute the principal obstacle to the development of these structures.