International Journal of Agriculture . 127 (2016) 431-435 https://sites.google.com/site/photonfoundationorganization/home/international-journal-of-agriculture Original Research Article. ISJN: 7758-2463: Impact Index: 4.12 International Journal of Agriculture Ph ton Potassium Phosphite As A Potent Fungicide: Review Bhise Kailas, Bhise Abhijeet, Vitekari Hrishikesh* Skylite Agrochem, Sangli, Maharashtra, India Article history: induce defence responses in plants against certain Received: 04 November, 2016 diseases. Phosphite works by boosting the plant's own Accepted: 05 November, 2016 natural defences and thereby allowing susceptible plants Available online: 05 December, 2016 to survive. It moves through the plant fast, both by Keywords: basipetal and acropetal transport. Potassium phosphite is Potassium phosphite, fungicide, plant a fungistatic molecule with low risk of pathogens developing resistance, and it is an environmentally Corresponding Author: acceptable active material. Its results can be enhanced by Hrishikesh V.* combination with other fungicides. Thus use of R & D Head, Skylite Agrochem Potassium phosphite is an effective way of prevention as Email: hrishi.kit ( at ) gmail ( dot ) com well as curative mode and indirectly for yield of crops. In this study, the review covers the chemistry, mode of Kailas B. Managing Director, Skylite Agrochem action and research data of Potassium phosphite use in modern agriculture. Abhijeet B. Managing Director, Skylite Agrochem Citation: Hrishikesh V.*, Kailas B., Abhijeet B., 2016. Potassium Abstract Phosphite As A Potent Fungicide: Review. International Journal Potassium phosphite is emerging as a vital fungicide in of Agriculture. Photon 127, 431-435 agriculture practices. It is a reduced form of traditional All Rights Reserved with Photon. fertilizer phosphate. Being a systemic fungicide, it works Photon Ignitor: ISJN77582463D848405122016 effectively against oomycetes and fungi. It is known to 1. Introduction Phosphorus and Potassium areprimary nutrients In addition to its solubility in both water and required by plants. Phosphorous is necessary for ethanol, the compound is also used to form foliar plant growth and it exists in nature as a fertilizer and as a fungicide. Phosphorous acid fullyoxidised form as phosphate anion (PO4) and (H3PO3) is neutralized with KOH, it forms the salt with one less oxygen as phosphite anion (PO3). On ofPhosphorous acid, potassium phosphite the other hand Potassium plays vital role in plant (KH2PO3) to form Potassium Phosphonate.Also photosynthesis. Potassium phosphite is widely used Phosphorous acid reacts with Potassium carbonate in the management of fungal diseases in to give Potassium phosphonate. agriculture, horticulture and natural environments (Daniel R.et al, 2005) . Potassium phosphite has H3PO 3+KOH →KH 2PO 3+H 2O also beenwidely used in agriculture for the many Or advantagesthat it offers, especially to increase 2H 3PO 3+K 2CO 3→2KH2PO3+CO 2+H 2O phosphorus uptakeby the plant compared to products based ontraditional phosphate(Cohen and Phosphite works by boosting the plant's own Coffey, 1986; Jackson, 2000). Potassium phosphite natural defences (Burra et al., 2014; Eshraghi et al., is also known as Potassium Phosphonate,Potassium 2011; Lim et al., 2013; Massoud et al., 2012). salt of Phosphorous acid and Potassium Phosphite is not toxic to people or animals and its dihydrogenphosphite. Monopotassiumphosphite is toxicity has been compared to table salt. There is a the potent form of Potassium phosphite. very low pollution risk associated with phosphite. When phosphite is sprayed on to the foliage of 1.1 Chemistry plants, it is applied at a very low rate, so any Potassium phosphite has a white-powdery phosphite that reaches the soil is bound to the soil appearance and a molecular formula of H 2KO 3P. and does not reach the water table (Tomlin, 2006). Ph ton 431 Potassium phosphonate is an agent that has a stems and leaves, allow various methods of systemic effect against fungal diseases, in application in accordance with the type of plant and particular against downy mildew (Pereira et al., characteristics of the pathogen to be controlled 2010). (Claudio O.et al, 2013)The Phosphite is highly mobile in trees and moves bi-directional in the 1.2 Mode of Action in Plant pholem and upward to the leaves in the vascular Potassium Phosphonates are systematically systems. Because Phosphite has one less oxygen absorbed by the plant and are mobile, within the molecule than phosphate, a higher degree of plant, trans-locating to the new growth, via both the solubility and mobility, within the plant is phloem element and the xylem. They are a highly achieved. This unique characteristic permits soluble form of Phosphorus and Potassium, which phosphites to be rapidly absorbed or taken up is beneficial to plant growth, rooting and root across the membranes of plant foliage and/or roots, development, accelerating foliar uptake of other in both their nutritive and plant protective roles, cations such as potassium, calcium, magnesium, with immediate activity on contact. and most micro elements, when applied in The efficiency of phosphite application in certain combination and by supplying more phosphorus pathosystems is due to the fact that the plant per molecule than phosphate. Not only does presents better assimilation in the presence of phosphite help roots, but is actually beneficial to phosphorus, making it capable of activating the regeneration of mycorrhizae on the roots of defense (Claudio O. et al, 2013; Nojosa et al., trees. Phosphorus and Potassium, are rapidly 2009). absorbed by the leaf tissue and roots for maximum and efficient plant use by moving systemically Potassium phosphite moves through the plant fast, upward and downward in the plants vascular both by basipetal and acropetal transport. It stops system, phloem and including the root system, myceliumgrowth and indirectly stimulates the bypassing typical soil phosphorus tie-ups with resistance of plants because phosphite encourages other soil, inorganic compounds. the production ofelicitin, which increases immunity Once applied and rapidly absorbed, by the plant, (Guest & Bompeix, 1990; Guest & Grant, 1991; phosphites undergo an oxidation or conversion Johnson et al., 2004, Lobato et al. 2008). process resulting in the continual release of soluble phosphorus. The phosphonates have been observed 1.3 Phosphatesvs. Phosphite to activate defense mechanisms that kick into gear Phosphite (Phi), a reduced form of phosphate when attached by disease or insects. This product (Pi). Many of us are familiar with MAP and DAP has fungistatic activity against major fungal (mono and di- ammonium phosphate) and possibly pathogens and has shown to promote the trees even MKP (monopotassium phosphate) all of natural defense systems capable of stimulating host which provide phosphorous derived from defenses through induced systemic resistance.The phosphoric acid (H3PO4). Plants use phosphate in mode of action of phosphorous acid is two fold, by the form of HPO4 and H2PO4 which once applied acting first within the fungus, inhibiting fungus to the soil is rapidly converted from fertilizers. growth, and also by changing the nature of the Phosphite is completely different in nature from fungal cell walls by activating the plants own phosphate. Chemically phosphate and phosphate immune defense response through rapid cytological are similar, however phosphate has one more action, and triggering other cellular phytoalexin oxygen than phosphite and this markedly changes accumulations and metabolic changes and other the nature and reactivity of the resultant molecule. resistance inducers. Phosphonates are highly These three oxygen molecules give phosphite selective, non-toxic fungicides against numerous formulations increased mobility in plant tissue and fungal pathogens, and provide both protective and soils so that they can be successfully applied to all curative responses against such plant diseases. It is areas of the plant. The recognized, traditional a highly systemic sterol inhibitor that penetrates source of phosphorus, as H3PO4, has long been and Trans-locates, preventing fungal cell phosphoric acid, and forms a salt when neutralized development, by interfering with cell wall with a base. The salt is referred to as phosphite, formation and growth throughout the plant by H3PO3,as opposed to the phosphate H3PO4. inhibiting sterol biosynthesis.Once the phosphite moves up the tree and enters the leaves, it 1.4 Remarkable results of Potassium Phosphite stimulates the production of infection-fighting Use chemicals within a layer known as the cambium. The use of potassium phosphite in the control of (www.chemjet.co.uk). the severity of plant diseases has shown Phosphites are quickly absorbed by plants; satisfactory results in diverse pathosystems, mainly therefore, they present a high degree of solubility those phytopathogens of the oomycota class, such and mobility. The systemic character (ascending as grape downy mildew, whose etiologic agent is and descending) and quick absorption by the roots, Plasmopara viticola (Pereira et al., 2010) and root Ph ton 432 rot caused by Pythium and Phythophtora (Daniel plantvia the xylem and phloem (Quimette and and Guest, 2006; Lobato et al., 2008).In many Coffey, 1990). research works It has been reported that Phosphorus as phoshponate group has some In a research, potassium phosphite was not fungicidal effect (Coffey and Joseph, effective in reducing P. brachyurus populations