Long-term and
short-term responses of morphology, anatomy, stomatal and photosynthesis of Arachis
pintoi to light stress
Nguyen Tien Anh Huy and Do Thuong Kiet
Res. J. Biotech.; Vol. 20(5); 152-158;
doi: https://doi.org/10.25303/205rjbt1520158; (2025)
Abstract
Pinto Peanut (Arachis pintoi Krapov. and W.C. Greg) is beneficial for reducing greenhouse
gas emissions, enhancing nitrogen fixation and serving as an important biomass for
livestock and medicinal purposes. As a leguminous plant, Pinto Peanut prefers humid
and shaded conditions, forming overlapping canopies but also shows long-term adaptation
to excessive light conditions. In this study, the changes in morphology, anatomical
structure and physiology of Arachis pintoi leaves were analyzed after long-term
excess light stress. Additionally, leaf damage and recovery after short-term light
stress were also examined.
The results showed that new growth shoots formed under direct sunlight had smaller
sizes, narrower leaf areas and doubled stomatal density compared to the control.
Although strong light reduced chlorophyll fluorescence density in the leaves, starch
presence remained high. For leaves subjected to short-term treatment, morphological
damage was mainly concentrated in the spongy mesophyll. This indicates that increased
transpiration and the sacrifice of spongy mesophyll are adaptive strategies of the
leaves. While morphological damage and reduced stomatal aperture could not be recovered,
overnight recovery of pigments and gas exchange activity of photosynthesis were
observed.
