The Granulate Cutworm (Lepidoptera: Noctuidae): Biological Parameters Under Controlled Conditions, Host Plants, and Distribution in the Americas

Feltia subterranea (Fabricius), commonly known as the granulate cutworm, is a common species of owlet moths (Noctuidae) of major agricultural importance, widely distributed in Nearctic and Neotropical regions. This study was conducted to determine the species biological parameters, gather information about its larval host plants, and assess the agricultural significance of this species in the Americas. The viability of the egg, larval, pupal stages, and prepupal period was 98, 98, and 100%, respectively, under laboratory conditions. The average duration of the egg, larval, pupal stages, and prepupal period was 3, 17, 4, and 13 d, respectively. All laboratory-reared larvae developed through five instars. The growth ratio was 1.93 for females and 1.85 for males. The duration of the larval stage was significantly longer in females than in males from the fourth instar. The duration of the pupal stage was significantly shorter in females than in males. When larval and pupal stage durations were combined, there were no significant differences in total development time as a function of sex. In total, 159 botanical taxa belonging to 41 families were recorded as host species for F. subterranea. The families with the greatest number of host species were Fabaceae (22), Poaceae (19), Asteraceae (16), Brassicaceae (13), Solanaceae (12), Amaranthaceae (7), Cucurbitaceae (7), and Malvaceae (5). It is noteworthy that the large number of native weeds used by F. subterranea as host plants could represent a significant source of infestation of crops in the agricultural landscape.

Population density, multiple harvesting, and ability of Ipomoea reptans to compete with native weeds at tropical wetlands

Lakitan B, Kartika K. 2020. Population density, multiple harvesting, and ability of Ipomoea reptans to compete with native weeds at tropical wetlands. Biodiversitas 21: 4376-4383. Despite as a nutritious, fast-growing, and well-adapted leafy vegetable at tropical wetlands; Ipomoea reptans has not been intensively cultivated yet. This study was designed for increasing productivity of this vegetable by optimizing population density, extending harvesting period, and its ability to compete with native weeds at tropical wetlands. Bottom wet culture system (BWCS) was implemented by placing all pots within 2 m x 4 m experimental pool filled with water to 2-cm depth to make sure bottom part of the substrate within each pot was continuously water-saturated. Results of this study indicated that despite fluctuated yield at each harvest, accumulative yields after five consecutive harvests were not significantly different among population densities from 14 to 71 plants per m2. Yet, quality of yield in most cases was better in lower population density treatment (14 plants per m2), as indicated by SPAD value and marketable size of individual plants. Frequent NPK fertilizer application was effective for increasing yield. The first harvest was done at 4 weeks after seed sowing; thereafter, the plants were routinely re-harvested at about every week. This fast-growing vegetable also exhibited ability to compete with native weeds commonly found at tropical wetlands at density up to 11.3 mg cm-2.

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); Margalef’s 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.

Non-legume plant species effects on soil nematodes abundance in a Regosol

The effects of a non-legume cover crop on total soil nematode abundance and soil groups of nematodes were investigated in a long-term field study. We compared total abundance of soil nematode and the abundance of both free-living soil nematode and root-feeding soil nematode under three different treatments (Pennisetum glaucum (L.) R. Br., native weeds and Caatinga moist-forest enclaves treatments) in a long-term field study cultivated on a Regosol. We found the highest abundance of free-living soil nematode in the Caatinga moist-forest enclaves treatment, whereas the highest abundance of root-feeding nematode was found in the native weeds treatment. We did not find any difference among P. glaucum and native weeds treatments for total abundance of soil nematode. Our findings suggest that the introduction of P. glaucum in sandy soil of Brazilian semiarid can increase the abundance of free-living nematode, but in other hand this cover crop did not reduce the abundance of root-feeding nematode. Our results also highlight the importance of considering the identification of soil nematode groups as indicator of soil quality and impacts of soil management.

Where Carbohydrates Were Key

The terrestrial ecosystems of California's islands have long been described as depauperate, with island peoples relying more heavily on marine resources and trading for plant resources with mainland neighbors. Island plant communities were decimated by more than a century of overgrazing, however, with heavy soil erosion and the introduction of non-native weeds. Since the removal of livestock, island plant communities are recovering dramatically, showing an unparalleled richness in plant taxa. Macrobotanical remains from island archaeological sites provide valuable data about plant use for the past 10,000 years, showing that island geophytes and grassland/forb fields were much more abundant and productive than previously thought. Island plants provided ample food, medicine, fuel, and raw materials for island peoples. This research has implications for understanding the archaeology and historical ecology of other islands or archipelagos where humans have heavily altered island ecosystems.

Alien Plant Species in the Agricultural Habitats of Ukraine: Diversity and Risk Assessment

This paper is the first critical review of the diversity of the Ukrainian adventive flora, which has spread in agricultural habitats in the 21st century. The author’s annotated checklist contains the data on 740 species, subspecies and hybrids from 362 genera and 79 families of non-native weeds. The floristic comparative method was used, and the information was generalised into some categories of five characteristic features: climamorphotype (life form), time and method of introduction, level of naturalisation, and distribution into 22 classes of three habitat types according to European Nature Information System (EUNIS). Two assessments of the ecological risk of alien plants were first conducted in Ukraine according to the European methods: the risk of overcoming natural migration barriers and the risk of their impact on the environment. The exposed impact of invasive alien plants on ecosystems has a convertible character; the obtained information confirms a high level of phytobiotic contamination of agricultural habitats in Ukraine. It is necessary to implement European and national documents regarding the legislative and regulative policy on invasive alien species as one of the threats to biotic diversity.