Formulations of different concentrations of Auxin and broad spectrum fungicide on yield, physical and biochemical parameters of kinnow Mandarin (Citrus reticulata Blanco)

Abstract

Kinnow (Citrus reticulata blanco) is high yield mandarin hybrid of two citrus cultivars ‘king’ (Citrus nobilis) and ‘willow leaf’ (Citrus deliciosa). Commercially, kinnow is one of the most successful fruit as it contributes good percentage to citrus fruit income. According to Nationnal Horticulture Database (2016-17) Punjab is the leading kinnow producing state of India. In Punjab progressive farmers prefer to grow kinnow because of its high yielding characteristics and its attractive quality that possesses the potential to give lucrative return in form of profit. Although kinnow cultivation is a profitable endeavor, it is liable to certain limitations resulting in less profit or even loss under worst circumstances. Pre-harvest fruit drop is major problem experienced by almost all farmers of kinnow plantation area. According to an estimate nearly 30-76% yield loss occurs due to pre-harvest fruit drop. There are large numbers of physiological and pathological reason responsible for pre-harvest fruit drop. The present study reports formulation of growth regulator and fungicide for reducing pre-harvest fruit drop in kinnow. Synthetic auxin naphthalene-1-acetic acid (NAA) and 2,4-Dichlorophenoxyacetic acid were used as a growth regulator. Carbendazim, broad spectrum benzimidazole fungicide was used to control fungi. Foliar application of formulation consisting of 20 ppm NAA and 0.2% carbendazim reduced the pre-harvest fruit drop by 18.92% as compared to untreated plants. Aforementioned formulation also increased the juice yield significantly. Thus, suggesting that combination naphthalene-1-acetic acid and carbendazim can be applied to reduce fruit drop in kinnow.