Ultrastructural response of wheat (Triticumaestivum L.) lines to potential allelopathy of Alstoniascholaris (L.) R. Br. leaf extract

Abstract

An investigation was carried out to evaluate the impact of the allelopathic effect of Alstonia scholaris leaf extract on morphoanatomical and physiological characteristics of 5 wheat lines. Three extract dilutions were prepared, viz. 0 (control), 15 and 30% of the aqueous extract and sprayed on wheat lines (3094, 5066, M5082, 7076 and A2011) at 15-day intervals until maturity from November 2017 to May 2018. All wheat lines responded differently to an allelochemical extract of A. scholaris. Disintegration of root parenchyma and transformation of stem chlorenchyma to sclerenchyma in stems were noted in Line 3094. Increased sclerification in the root cortex (141.7-212.5 µm) and stem hypodermal region (212.5-354.2 µm) was recorded in Line 5066. Line M5082 showed intensive sclerification in the root cortex and vascular region, and around stem vascular bundles along with a significant decrease in leaf thickness. Line 7076 was the most sensitive genotype showing significant reduction in the stem (1402.8-821.8 µm) and root area (963.5-791.9 µm) and leaf thickness (1346.2-396.8 μm). Line A2011 responded very differently by increasing proportion of parenchyma and sclerenchyma. A low concentration (15%) of allelochemical extract promoted growth and development and a high concentration (30%) was toxic, causing growth retardation and tissue damage.

Allelochemicals extract of star fruit (Averrhoa carambola L.) modulates wheat growth through alterations in anatomical architecture

“…The decrease in growth traits were mainly due to a decrease in storage tissue (cortical parenchyma), mechanical tissue (sclerenchyma), vascular tissue (xylem and phloem) and dermal tissue (epidermis), as reported by Golzardi et al (2015), Feitoza et al (2018) and Hameed et al (2020). Estimated response curves showed high plasticity of morphological, anatomical and physiological traits in response to different concentrations of allelochemicals.…”

“…In a pilot experiment, as already published in our earlier paper by Hameed et al . (2020), the allelochemical effects of Alstonia scholaris leaf extract were tested on five wheat lines (3094, 7076, A2011 3094 and M5082). Based on the findings of this experiment, three wheat lines, 3094, 7076 and A2011 were selected for testing their response to A. carambola L. (star fruit) leaf extract applied as foliar spray.…”

Ultra-Responses of Asphodelus tenuifolius L. (Wild Onion) and Convolvulus arvensis L. (Field Bindweed) against Shoot Extract of Trianthema portulacastrum L. (Horse Purslane)

“…Metaxylem cell area decreased at concentrated treatments of shoot extract in C. arvensis and A. tenuifolius . As reported by many researchers, such as Hameed et al [ 40 ], a decrease in metaxylem area in wheat varieties is observed at a higher level of leaf extract of A. scholaris. However, an increase in the metaxylem cell area of A. tenuifolius at diluted shoot extract was consistent with the finding of Chen et al [ 41 ], who reported an increase in the metaxylem cell area and vascular bundle area at high salinity levels in wild barley.…”

“…An increase in metaxylem cell area in C. arvensis at concentrated shoots extract levels favors the stronger tolerance against the biotic stresses, as water and mineral translocation may be easier, and this was a crucial adaptation against harsh environments (Ruiz et al [ 44 ]). While the decrease in this parameter in A. tenuifolius was fully reinforced by Hameed et al [ 40 ], who described that leaf extract of A. scholaris caused a decline in the metaxylem cell area in wheat lines. Vascular bundle area reduction in A. tenuifolius was supported by Nassar et al [ 45 ], who affirmed the reduction in a vascular bundle area with the application of abiotic stress.…”

Antigerminative Effects of Ethanolic Crude Extracts from Devil Tree (Alstonia scholaris) on Seed Germination and Seedling Growth against Selected Plants

“…The crude extracts from the leaves of devil tree (A. scholaris) showed the allelopathic effects on seed germination and radicle growth against of two tested plants (Bidens pilosa and Lactuca sativa) (Wang et al, 2014). Hameed et al (2020) noted that the allelopathic effects of the crude extracts from the leaves of devil tree (A. scholaris) on the stem growth character and root area character in wheat for two choices, the first choice that focused, the crude extracts from the leaves of devil tree (A. scholaris) showed reduction in stem growth and exhibited reduction in root area of wheat as well as the second choice focused, the crude extracts from the leaves of devil tree (A. scholaris) caused the growth retardation of wheat and showed the tissue damage of wheat. Sawatdikarn et al (2011) impressed that the allelopathic activity from the leaves of devil tree (A. scholaris) showed the reduction of percentages of seed germination against mungbean and black gram) as well as the allelopathic activity from the leaves of devil tree (A. scholaris) exhibited the reduction of seedling growth interm of tem height, number of leaf, leaf width and leaf length against mungbean and black gram.…”