15 research outputs found
Management practices for control of ragwort species
The ragwort species common or tansy ragwort (Jacobaea vulgaris, formerly Senecio jacobaea), marsh ragwort (S. aquaticus), Oxford ragwort (S. squalidus) and hoary ragwort (S. erucifolius) are native in Europe, but invaded North America, Australia and New Zealand as weeds. The abundance of ragwort species is increasing in west-and central Europe. Ragwort species contain different groups of secondary plant compounds defending them against generalist herbivores, contributing to their success as weeds. They are mainly known for containing pyrrolizidine alkaloids, which are toxic to grazing cattle and other livestock causing considerable losses to agricultural revenue. Consequently, control of ragwort is obligatory by law in the UK, Ireland and Australia. Commonly used management practices to control ragwort include mechanical removal, grazing, pasture management, biological control and chemical control. In this review the biology of ragwort species is shortly described and the different management practices are discussed
An overview of NMR-based metabolomics to identify secondary plant compounds involved in host plant resistance
Secondary metabolites provide a potential source for the generation of host plant resistance and development of biopesticides. This is especially important in view of the rapid and vast spread of agricultural and horticultural pests worldwide. Multiple pests control tactics in the framework of an integrated pest management (IPM) programme are necessary. One important strategy of IPM is the use of chemical host plant resistance. Up to now the study of chemical host plant resistance has, for technical reasons, been restricted to the identification of single compounds applying specific chemical analyses adapted to the compound in question. In biological processes however, usually more than one compound is involved. Metabolomics allows the simultaneous detection of a wide range of compounds, providing an immediate image of the metabolome of a plant. One of the most universally used metabolomic approaches comprises nuclear magnetic resonance spectroscopy (NMR). It has been NMR which has been applied as a proof of principle to show that metabolomics can constitute a major advancement in the study of host plant resistance. Here we give an overview on the application of NMR to identify candidate compounds for host plant resistance. We focus on host plant resistance to western flower thrips (Frankliniella occidentalis) which has been used as a model for different plant species
Biochemical components of wild relatives of chickpea confer resistance to pod borer, Helicoverpa armigera
Efforts are being made to develop chickpea varieties with resistance to the pod borer, Helicoverpa armigera for reducing
pesticide use and minimizing the extent of losses due to this pest. However, only low to moderate levels of resistance have
been observed in the cultivated chickpea to this polyphagous pest. Hence, it is important to explore wild relatives as resistance
sources to develop insect-resistant cultivars. Therefore, we studied different biochemical components that confer resistance to
H. armigera in a diverse array of wild relatives of chickpea. Accessions belonging to wild relatives of chickpea exhibited high
levels of resistance to H. armigera as compared to cultivated chickpea genotypes in terms of lower larval survival, pupation
and adult emergence, decreased larval and pupal weights, prolonged larval and pupal developmental periods and reduced
fecundity of the H. armigera when reared on artificial diet impregnated with lyophilized leaf powders. Amounts of proteins
and phenols in different accessions of chickpea wild relatives were significantly and negatively correlated with larval weight,
pupation and adult emergence. Phenols showed a negative correlation with pupal weight and fecundity, but positive correlation
with pupal period. Total soluble sugars showed a negative correlation with larval period, but positive correlation with
pupation and pupal weight, while tannins showed a positive correlation with larval weight, pupation and adult emergence.
The flavonoid compounds such as chlorogenic acid, ferulic acid, naringin, 3,4-dihydroxy flavones, quercetin, naringenin,
genistein, biochanin-A and formononetin that were identified through HPLC fingerprints, exhibited negative effects on survival
and development of H. armigera reared on artificial diet impregnated with lyophilized leaf powders. The wild relatives
with diverse mechanisms of resistance conferred by different biochemical components can be used as sources of resistance
in chickpea breeding programs to develop cultivars with durable resistance to H. armigera for sustainable crop production
Mixture-Amount Design and Response Surface Modeling to Assess the Effects of Flavonoids and Phenolic Acids on Developmental Performance of Anastrepha ludens
Towards eco-friendly crop protection: natural deep eutectic solvents and defensive secondary metabolites
Plant science