Accessing the nursing behaviour and the harvest timing for multiple utilisation purposes of moso bamboo ( Phyllostachys edulis ) via carbohydrates and chlorophyll fluorescence.

Shitephen Wang

doi:10.31220/osf.io/652hy

Abstract

Abstract Context: Nursing behaviour, also known as breastfeeding behaviour, is the feeding of juvenile individuals with nutrients or proteins from matures especially in mammals. As a hypothetical phenomenon in bamboo forests, mature bamboos have transferred photoassimilates to young bamboos for recovering and rebuilding their photosystems especially 16 in winter. This process is accompanied by changes in the ability of photosystems and the mass fraction of non-structural carbohydrates (NSCs), structural carbohydrates (SCs), and lignin. Aims: Clarify the nursing behaviour and reveal timings to harvest moso bamboos for multiple purposes of utilisation. Methods: We analysed carbohydrates and chlorophyll fluorescence to compare the physiological traits in mature (age 2, 3, 4) and immature (age 1) moso bamboos ( Phyllostachys edilus ) during a year using the Portable Chlorophyll Fluorometer (PCF) and the Liquid Chromatographic (LC) method. Results: The results showed that the mass fraction of total soluble carbohydrates (TSCs) and starch in the bottom of bamboo at age 1 was higher than other parts and ages in spring, whereas the mass fraction of TSCs, starch, and sucrose at age 3 was higher than other parts and ages in winter. The Fv/Fm, an indicator to reveal photosystems were 31 functional or not, at age 1 dramatically dropped when the cold current attacked first time in October, and then quickly recovered in November. Conclusion: Our findings indicate that mature bamboos very possibly provide carbohydrates to immature bamboos and help them rebuild their photosystems when a bamboo forest resists cold stress. Furthermore, old bamboos (≥ age 5) are less likely to be infected by insects because of its low starch content suited for traditional utilisation. (such as making chopsticks and furniture). And they also can be used to torrefact bamboo for producing biocoal during summer, autumn, and winter. Harvested young bamboo (age 1) in summer is suit for making bioethanol.

Highlights

Moso bamboo (Phyllostachys edilus) is a kind of broadly distributed bamboo species with its leptomorph rhizome systems in east Asia (Chen et al 2016; Isagi et al 1997; Song et al 2017; Wang et al 2009)
The results showed that the mass fraction of total soluble carbohydrates (TSCs) and starch in the bottom of bamboo at age 1 was higher than other parts and ages in spring, whereas the mass fraction of TSCs, starch, and sucrose at age 3 was higher than other parts and ages in winter
Our findings indicate that mature bamboos very possibly provide carbohydrates to immature bamboos and help them rebuild their photosystems when a bamboo forest resists cold stress

Summary

Introduction

Moso bamboo (Phyllostachys edilus) is a kind of broadly distributed bamboo species with its leptomorph rhizome systems in east Asia (Chen et al 2016; Isagi et al 1997; Song et al 2017; Wang et al 2009). Because it has leptomorph rhizome systems, some studies assume that mature bamboos perhaps provide nutrients and carbohydrates to bamboo shoot (Song et al 2016) and juvenile bamboos (Chen et al 2016; Yen et al 2010; Yen, 2016) This phenomenon may be called a kind of "nursing behaviour" which helps juvenile individuals (e.g. bamboo shoots and young bamboos) to quick grow or recover photosynthetic function after extreme weather events in bamboo forest. NSCs probably can provide a temporary source of carbon when current photosynthesis cannot meet the immediate carbon demands of bamboo (Cui et al 2012)

Methods

Discussion

Conclusion