In a field experiment, three-year-old Kinnow trees budded on Jatti Katti (C. jambhiri) rootstock were inoculated by three different arbuscular mycorrhiza (AM), Glomus manihotis (T1), Glomus mosseae (T2), and Gigaspora gigantia (T3), separately or in combination (T4). Microscopic assessment of AM colonization on Kinnow roots showed a relatively lower level of infection by different species when inoculated separately than when inoculaed together. Application of AM improved growth parameters like plant height, canopy volume, mean leaf area, and number of new shoots per plant but had no effect on trunk diameter, number of leaf per new shoot and new shoot diameter. Flowering phenology was also altered by AM infection. The infected plants produced more flowers which despite abscission caused an increase in the initial number of fruits. AM inoculation increased plant phosphorous in T3, potassium in T1, T2, T3, calcium in T2, T3, T4, and the AM-nutrient relationship did not reveal any generalized pattern. Inoculated plants, however, had higher concentration of different elements by the second year of the experiment indicating towards the continuous and cumulative effect of AM infection on plant nutrient accumulation. Further, the beneficial effects of AM on Kinnow were not related to the difference in the species of mycorrhiza. 1. Introduction There have been many scientific reports suggesting that inoculation with arbuscular mycorrhiza may cause an additive or synergistic growth enhancement of the inoculated host plant [1]. Enhanced plant growth by arbuscular mycorrhizal fungi (AMF) is determined by the dependency of the plant on the fungi, the ability of the fungi to forage away from the root for nutrients, especially P, the nutrition level of the growth medium itself, and other factors. The primary effect of AM symbiosis is to increase the supply of mineral nutrients to the plant, particularly those whose ionic forms have a poor mobility rate or those which are present in low concentration in the soil solution leading to the better growth and development of host plant [2]. It is postulated that species variation in AM fungi may cause difference in the crop growth due to their effect on certain key plant physiological processes. AM influence on optimizing the availability and uptake of mineral nutrients in the rhizosphere is one such important regulator of plant growth and development. Tang and Wan [3] observed an increase in shoot length and leaf area of mycorrhizal citrus seedlings than noninoculated control. Inoculation with different AM species, Glomus
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