Oils, plant agricultural applications

ISMAN, M.B., Plant essential oils as green pesticides for pest and disease management, in Agricultural Applications in Green Chemistry (W.M. Nelson, ed.), American Chemical Society, Washington. 2004, in press. 

Minshall and Helson (7) of the Dominion Department of Agriculture at Ottawa, Canada, have studied the physiological action of petroleum naphtha on carrots, parsnips, and several weeds including mustard. They used infrared absorption apparatus, and by means of readings taken at 10-second intervals following oil application, determined that photosynthesis ceased abruptly for all plants studied. With parsnips, photosynthesis was resumed within 30 minutes after application it was one third of norm at the end of 3 hours, and at the end of 48 hours reached approximately the original rate before treatment. Parsnips did not wilt following treatment. The common mustard plant had a... 

Kalra, A., Parameswaran, T.N., Ravindra, N.S., Rao, M.C. and Kumar, S. (2000) Effects of planting date and dinocap applications on the control of powdery mildew and yields of seed and seed oil in coriander. Journal of Agricultural Science 1 35(2), 1 93-1 97. 

Numerous herbicides are currently recommended and used for weed control in agricultural, industrial, and recreational areas. However, the method of formulation and application of such chemicals to plants or soils may markedly affect their biological efficacy and persistence. Chemical additives (primarily surfactants) in both oil and aqueous sprays are already used widely, and when properly understood, promise a virtual revolution in the use of agricultural chemicals. Conceivably, not only weed control performance and herbicidal selectivity can be altered but also distribution, metabolism, and accumulation of chemical residues. With the widespread introduction and increasing use of chemical additives in weed science and technology, we must therefore learn to reflect on what before we knew about the use of herbicides. 

The noninvasive nature of NMR spectroscopy combined with the chemical specificity of the NMR method provides direct access to the distribution of various chemical constituents for the histochemistry of plant materials in situ NMR spectroscopy can be used to identify the major constituents, and chemical-.shift imaging can be used to spatially localize them. The latter can be applied to localize aromatics, carbohydrates, as well as water and fat or oil in plant samples. The suitability of many fresh fruits and living plants to be studied by NMR imaging results in a variety of applications in agriculture and food science [Mcc I, Mcc2]. 

---