Feng, Y. L. | Search bioRxiv

bioRxiv2020

Competitive approach of invasive cocklebur (Xanthium strumarium) with native weed species diversity in Northeast China

Xanthium strumarium is yearly weed local to North America and is presently an obtrusive species. The intrusive weed can contend with local decent variety may turn into a hazardous weed for the agrarian profitability and rangeland biological systems. The present examination researched the challenge of intrusive and local weed populaces inside two straight out variables in matched quadratic rings (treatment/invasive with control/non-invasive). The present investigation was led at four unique areas of northeast China to discover competition of Xanthium strumarium on 40 paired matched vegetations in same condition and living space conditions. The number of species (NOS) occurred in quadratic ring; abundance (A); Simpsons Diversity Index (SDI); Margalefs Richness Index (MRI) compared between invasive and non-invasive quadrates by t-test was recorded significant (P<0.05) suggestion of competitions between plant communities. The abundance in communities decreased significantly in invasive compared to non-invasive quadrate gave an indication about low productivity of plant species due to Xanthium strumarium. Rarefaction bend with respect to coefficient of determination (R2) explored in the overviewed network (0.86) proposed that there is a solid positive polynomial connection between various weed families. Greatest difference list (87.06%) recorded in Huailai province followed by Yangyuan (44.43%), Zhangjiakou (40.13%) and at Fushun (29.02%). Significant (P<0.05) maximum global R demonstrated high species decent variety was found in Huailai area (0.943) trailed by Zhangjiakou. Significant (P<0.05) density of native weed was recorded in non-invasive quadrate which was comparable to the invasive quadrate. Finally invasive Xanthium strumarium compete with native weeds diversity created significant threat to the natural diversity. Most extreme thickness of weed species gave cautioning that the predominant edaphic and natural states of the uneven regions are profoundly favorable for the dispersion and development of the weed in future.

ecology↗

bioRxiv2020

Phytochemical screening, GC-MS profiling of invasive cocklebur (Xanthium strumarium)-insect-pathogen interaction and simulated volatile chemical signaling at Northeast China

Invasive cocklebur (Xanthium strumarium) is characterized by its excellent genetic and ecological plasticity, ability to spread in agriculture crops. There is a dire need to locate useful management strategies to control this invasive weed at diversified latitudinal gradients. In ecology, there is weak evidence that the damage caused by the natural enemy varies with latitudes. Therefore, we investigated this evidence with the help of transect quadratic ecological sampling method which was conducted randomly at ten different sites of Northeast China. Overall, significantly high infestation of gall-forming insect (Epiblema strenuana) was observed on Xanthium leaves (21.16%) at 41.51279{degrees}N, followed by 40.2241{degrees}N latitude. Similarly, there was a significantly high abundance of Epiblema infestation (7.3) with high damage (3.88%) at 41.51279{degrees}N and 40.12749{degrees}N latitude. Likewise, the fungal abundance (5.6) of rust i.e. Puccinia xanthii (presenting 16.23% attack) was dominated significantly at 41.51279{degrees}N. Hence, high pathogen infection rate (8.97%) was detected at 40.2241{degrees}N. On the other hand growth parameters, i.e. plant height (cm), stem diameter (mm) vary with latitude and longitudinal trends. In our experiment, of plant natural enemy interaction provides the evidence-based indication the Epiblema abundance, was diversified at 41.51279{degrees}N, and P. xanthii infection was most frequent at 40.22411{degrees}N latitudes. This study provides an evidence-based indication that natural enemy pressure varies with latitude, however this investigations gave valuable information that insect and phytopathological fungus having biological control potential against Xanthium strumarium invasive weed. Secondly, phytochemical qualitative and chemical signaling through Gas Chromatography-mass spectrometry (GC-MS) executed the presence of flavonoids, phenols, saponins, alkaloids, terpenoids, nitrogen (N), sulpher (S), silicon (Si) containing compounds in both treated and controlled leaves that defend against Puccinia xanthii. Fascinatingly, all X. strumarium populations collected from different latitudes possess similar compositions. In interaction mechanism, plant known to omit volatile organic compounds in response to attack of natural herbivores. The leave chemical profiling suggested that the influence of fungus attack on invasive weed brought different changes in chemical infrastructure of leave and these chemicals also play a vital role in the food web. After attack of these biological control agents, plants exhibits passionate compound reprogramming within the leaf naturally that act upon in defense systems. Author summaryO_LIThe study was conducted to observe the environmental impact on the trend of insect, invasive weed and pathogens. C_LIO_LIThere was a significant dominance of gall-forming insect on invasive Xanthium weed at all locations. C_LIO_LIPuccinia xanthii infected more than 16% plantation C_LIO_LIPlant growth had significant variation at various longitudes and latitudes. C_LIO_LIThe abundance of insect was positively linked with different environmental factors and Xanthium plant. C_LIO_LIThe results of GC-MS suggested that Puccinia xanthii infected (treatment) leaves covered maximum area (%) compared to control treatments due to breakdown of the chemical compounds that proved our hypotheses that volatile organic compounds altered infrastructures of the leave chemistry that led to activeness of plant defensive chemicals resulted invasion success. C_LI

biochemistry↗