Macro- and Microscopic Analyses of Anatomical Structures of Chinese Gallnuts and Their Functional Adaptation

Qin Lu,Hang Chen,Zi-Xiang Yang,Xiao-Ming Chen,Chao Wang,Ming-Shun Chen,Pin Lü

doi:10.1038/s41598-019-41656-6

Abstract

The galls induced by Schlechtendaia chinensis, Schlechtendaia peitan and Nurudea shiraii on Rhus chinensis and gall induced by Kaburagia rhusicola rhusicola on Rhus potaninii Maxim. are the largest plant galls and have great economic and medical values. We examined the structures of galls and their functional adaptation using various macro- and microscopic techniques. The highly adapted structures include a stalk at the base that is specialized for mechanical support and transport of nutrients for aphids, and a network of vascular bundles which accompanying schizogenous ducts arranged in a way to best support aphid feeding and population growth. There are many circular and semicircular xylems traces in an ensiform gall in cross sectional views, which would provide more nutrition and occupy less space. We infer the evolution trail was flower-like gall, horned gall, circular gall and ensiform gall. And the possible evolutionary trend of the gall was bigger chamber, more stable mechanical supporting, easier for exchanging substance and transporting nutrients.

Highlights

Among the gall-inducing organisms, aphididae-induced galls are estimated to represent 10–20%1
(1) How can individual galls provide sufficient nutrition for a rapid and dramatic population expansion of aphids? (2) Are there specialized gall structures that provide favorable environments for aphid population expansion? (3) What are the differences among the different galls? We choose four shapes of gall: horned-gall, ensiform gall, circular gall and the flower-like gall which were widely used in forestry production in china
The Rhus chinensis and Rhus potaninii were small deciduous tree, the height of trees were more than 10 m in the late stage, and the trees could induce the gall from three years old to death

Summary

Introduction

Among the gall-inducing organisms, aphididae-induced galls are estimated to represent 10–20%1. No dense tissues or www.nature.com/scientificreports rachis wing (Rhus chinensis) leaf (Rhus chinensis) leaf (Rhus potaninii) axillary bud (Rhus chinensis) nutritive cellular layers were found inside aphid galls. This type of gall structures is thought to be an adaptation to insects with sucking mouthparts such as aphids[12,18,19]. One of the most interesting phenomena of these gall-inducing aphids is the rapid and dramatic expansion of aphid populations within a short time period in individual galls. (1) How can individual galls provide sufficient nutrition for a rapid and dramatic population expansion of aphids? The objective of this study is illustrate the differences of four type galls in their anatomical structure by examine the localization, inner and outer surface of the gall, connecting networks of galls, and analyze potential connections between structures and gall functioning

Objectives

Methods

Results

Conclusion