Kaolin Particle Film Product Applications Before Harvest Begins May Not Improve Marketable Yields of Fresh Tomatoes

Abstract

<jats:p>Drip-irrigated, stake-and-weave supported tomato (<jats:italic>Lycopersicon esculentum</jats:italic>) plots were established in 2005 and 2006. All plots (except controls) were treated with a kaolin particle film product (Surround WP) mixed at 0.5 lb/gal of water and applied with a pressurized hand sprayer. Sprays began after transplanting and were repeated as needed to maintain a particle film on the foliage. Sprays were discontinued either at anthesis, at first green fruit 5 cm in diameter, or at first colored fruit harvest. Multiple hand harvests were made as fruit matured. In 2005, all kaolin treatments reduced marketable fruit number and weight, whereas in 2006 there were no significant effects. Cull fruit weight and average weight per marketable fruit were unaffected by treatments during either year. Results indicate that when applied before harvest begins, Surround may not improve marketable yields of fresh tomatoes.</jats:p>

Potential and actual uses of zeolites in crop protection

“…Tests indicate a higher leaf carbon assimilation rate and a reduced canopy temperature in grapefruit and apples . That explains why this product is labelled for reduction of heat stress and sunburn on several crops . Kaolin cools tissues and protects plants from extreme heat and ultraviolet radiation by increasing leaf reflectance and reducing transpiration rate .…”

“…24,65,67 That explains why this product is labelled for reduction of heat stress and sunburn on several crops. 4 Kaolin cools tissues and protects plants from extreme heat and ultraviolet radiation by increasing leaf reflectance and reducing transpiration rate. 68 Experiments with kaolin demonstrated that leaf temperature increases linearly with increasing light intensity.…”

“…89 Zeolites in soils exchange sodium (Na + ) and potassium (K + ) cations for ammonium (NH 4 + ). 90 Ammonium and potassium charged zeolites have shown their ability to increase the solubilisation of phosphate (PO 4 3− ) and the capture of nitrate (NO 3 − ). In addition, the inclusion of negatively charged nitrate ions promotes the uptake of positively charged nutrient ions, such as magnesium, calcium and potassium.…”

“…Current research is based on the use of nanoparticles and their potential role in agriculture to reduce the negative impacts of environmental stresses on crop plants, to suppress diseases and to protect crops from insect pests. 4 This approach has been applied by making use of dust applications. However, such material has some drawbacks -see the discussion of kaolin-based particle films used on plant surfaces in Section 2.…”

INFLUENCE OF IRRIGATION LEVELS, ANTITRANSPIRANTS AND POTASSIUM SILICATE ON GROWTH, FRUIT YIELD AND QUALITY OF SWEET PEPPER PLANTS (Capsicum annuum L.) GROWN UNDER DRIP IRRIGATION

“…In this respect, Abd El-Aal et al (2008) mentioned that foliar application of MgCO3 at rate 2% gained more growth vigor and more fruits yield as well as better physical and chemical properties of eggplant compared with no-treated plants. Kaolin also is an important material used in this concern, it is considered as an effective natural antitranspirant and was reported to mitigate the negative effects of water deficiency and environmental stresses, such as heat stress and sunburn damage as well as suppress diseases and protect crops from insect pests (Kahn and Damicone, 2008). Spraying tomato plants with 5% of kaolin suspension improved water status and yield under water stress conditions (Srinivasa Rao, 1985).…”