Development of plastids in pollen and tapetum of rye-grass, Lolium perenne L

Proplastids of both tapetal cells and microsporocytes were present early in anther development. Tapetal proplastids differentiated—probably into elaioplasts—at late microspore stage. The tapetal cytoplasm was completely resorbed by early tricellular pollen stage. Microspore proplastids differentiated into amyloplasts at early bicellular stage, and were present in both vegetative and generative cells. In the generative cell, the amyloplasts were ephemeral and apparently degenerated within autophagic vacuoles. Plastids were absent from sperm cells. Vegetative cell amyloplasts increased in number apparently by fission such that one amyloplast produced one amyloplast and one proplastid per division. Mature pollen grains were estimated to contain between 550 and 820 amyloplasts with only one starch granule per plastid.

Nanostructured liquid crystalline particle assisted delivery of 2,4-dichlorophenoxyacetic acid to weeds, crops and model plants

Routine agricultural practices are heavily dependent on the use of surfactants, many of which are toxic to humans and detrimental to the environment. In proof of concept work we have previously shown the potential of nanostructured liquid crystalline particles (NLCP) to safely interact with plant leaf cuticular surfaces with minimal impact on epicuticular waxes. Here we demonstrate the use of NLCP to effectively deliver the auxin herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) to plant leaves in laboratory and field studies. In the laboratory, the physiological stress responses of lupin, Lupinus angustifolius (L.) (Fabaceae) towards NLCP spray applications were shown to be much reduced in comparison with application of two common surfactants. Phytotoxicity assays of 2,4-D loaded NLCP were used to validate the herbicidal effects on Arabidopsis thaliana (L.) Heynth. (Brassicaceae) and established a similarity with that of surfactant assisted 2,4-D delivery when tested at a concentration of 0.1%. Field trials were conducted to test the efficacy of NLCP-assisted delivery of 2,4-D in comparison with commercial surfactants for the control of the invasive weed wild radish, Raphanus raphanistrum (L.) (Brassicaceae), in wheat, Triticum aestivum (L.) (Poaceae) crop fields. Compared against Estercide 800, a commercially available 2,4-D formulation, NLCP assisted delivery of 2,4-D was effective at low concentrations of 0.03% and 0.06%. The crop yield remained similar for all the tested concentrations and formulations of 2,4-D loaded NLCP and Estercide 800. This is the first report to directly show that, as an alternative to conventional methods, NLCP can be used under both laboratory and field conditions to successfully delivery an agrochemical.