CORRELATION OF BIOCHEMICAL LEAF TRAITS AND GALL FORMATION IN SIX CULTIVARS OF MANGO, Mangifera indica L.

Abstract

Mango (Mangifera indica L.) leaves are susceptible to severe attack by insect gall formers. The study's objective was to assess how different vertical strata of the tree canopy and variation in leaf traits affect gall formation. For this, individual and temporal variation in leaf traits of different mango cultivars (Anwar ratole, Chaunsa, Dusehri, Fajri, Sindri and Siroli) and their ultimate effect on gall formation were studied in 2009-10. In addition, the approximate quantity of carbon, nitrogen, phosphorus, potassium and water content in the leaves was also analysed. Significant variation was found among all mango cultivars for leaf traits and gall formation (p<0.05). Within host individuals, a maximum level of gall formation (200-240 galls, in case of Fajri cultivar) was found on the foliage of the upper tree canopy followed by the lower and inner canopy with the consistent pattern over 2 years. Moreover, gall formation showed significant correlation to carbon to nitrogen (C/N) ratio, phosphorus and potassium level in the leaves of all the studied cultivars except Siroli.

A study on the effect of host plants on Chinese gallnut morphogenesis

“…In other studies, gall formation was found to be affected by different vertical strata of the tree canopy and variations in leaf traits [ 18 , 19 ]. Gall abundance on Mangifera indica leaves was found to be higher in the upper than the lower zone of the plant canopy, which on its turn was higher than in the inner zone [ 20 ]. In a type of aphidic gall, the number/size of the gall is different when a kind of aphid feeding on the different site of the same host [ 21 ].…”

“…Fusiform and horned galls have certain common traits, such as specific reticulate schizogenous ducts associated with the vascular bundles, that fill the inner wall, and expanded xylem in the stalk that serves as a strong support and facilitates the exchange of nutrients [42]. As mentioned above, some studies have shown that the host plant can affect the anatomy and metabolism of galls [20][21][22][23]. In this study, we tested two galls produced by two galling aphids, and hypothesized that the morphology and developmental pattern differ because of their different stimulation sites.…”