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Despite the existence of three competing reactions for propargyloxyoxindoles, we report a chemoselectivity switch between enantioselective propargyl [2,3]‐Wittig rearrangement and Conia‐ene‐type reactions, with suppression of the [1,2]‐Wittig‐type rearrangement. Using C1‐symmetric imidazolidine‐pyrroloimidazolone pyridine as the ligand and Ni(acac)2 as the Lewis acid, diverse 3‐hydroxy 3‐substituted oxindoles containing allenyl groups were obtained in up to 98 % yield and 99 % ee via asymmetric propargyl [2,3]‐Wittig rearrangement. In the presence of AgOTf‐Duanphos, chiral spiro dihydrofuran oxindoles were given in up to 98 % yield and 91 % ee through a Conia‐ene‐type reaction. [ABSTRACT FROM AUTHOR]

Yunnan province is most important area of potato planting in China. Meanwhile, there are many factors constraint to its developments, especially pest damage. So, eleven potato cultivars (such as Hezuo 88, Lishu 6, Qingshu 9 and Yunshu 304) of vital commercial variety in Yunnan were selected for pests investigation. The field survey of eleven potato cultivars in two cropping seasons (spring and autumn) was conducted from 2020 to 2021 in Yunnan province, China. During autumn planting season of 2020 and 2021, populations of eight insect pests including aphid, thrips, whitefly, leafhopper, potato tuber moth, tomato leaf miner, beet armyworm and cabbage moth were surveyed. All pest's population peaked in October. Meanwhile, Qingshu 9 and Yunshu 304 has the largest population of aphid. The largest population of whitefly were reported on Hezuo 88 and Yunshu 304, respectively. The largest population of thrips were found on Hezuo 88, whereas Qingshu 9 has the lowest population of whitefly. The lowest population of aphid were observed on Lishu 6. The lowest population of thrips were found on Yunshu 304. During spring planting season of 2021, population of thrips, leafhopper and adult potato tuber moth were surveyed. The highest population was appeared in June. But there was no significant difference for the pests populations among different cultivars. These results of pests population dynamics during the cropping period would be helpful for making appropriate and sustainable pest management strategies. [ABSTRACT FROM AUTHOR]

The potato tuber moth, Phthorimaea operculella, is the most damaging potato pest in the world and is difficult to control as the larvae are internal feeders in the foliage and tubers. Entomopathogenic fungi that colonize plants as endophytes have lethal and sublethal pathological effects on insect pests. We show that Beauveria bassiana colonizes the aerial parts of potato plants endophytically after inoculation through soil drenching. Endophytic B. bassiana persisted in potato foliage for more than 50 days postinoculation. Bioassays indicated that foliage of B. bassiana‐inoculated potato plants were pathogenic against larvae of P. operculella. Sublethal experiments indicated that B. bassiana negatively affected the growth, development, and reproduction of P. operculella. Development experiments showed that the weight of P. operculella pupae reared on B. bassiana‐colonized potato plants (4.25 mg) was significantly less than that of those reared on uninoculated control plants (8.89 mg). Compared with newly eclosed larvae fed on control plants, those fed on B. bassiana‐inoculated plants had significantly lower survivorship, with only 17.8% developing to the adult stage. Oviposition of P. operculella females reared on B. bassiana endophytically colonized plants was significantly lower (35 eggs/female) than of those reared on uninoculated plants (115 eggs/female). This study demonstrates that endophytic B. bassiana can be a potential biological control agent for the control and management of P. operculella. Comparing pupal weights of P. operculella reared on potato plants inoculated with the B. bassiana strain GZGY‐1‐3 and on untreated control plants, pupae from the control plants were significantly heavier than those from treated plants. [ABSTRACT FROM AUTHOR]

Simple Summary: In this article, we studied the interactions between the invasive thrips pest Frankliniella occidentalis (WFT) and a native thrips Frankliniella intonsa (IFT) in China, where they co-exist on crop plants and WFT seems to outcompete IFT. In laboratory bioassays we focused on the reproductive mode of the thrips (sexual or parthenogenic), and the presence of a sugar source (honey or flowers), both variables that change over time during pest colonisation of a crop. Our results suggest that in the early stages of F. occidentalis invasion, the provision of honey (flowering) promotes this pest's population development. This research will inform effective strategies for the management of F. occidentalis invasion and help reduce subsequent crop damages. Background: Flower thrips (Frankliniella intonsa, IFT) and west flower thrips (Frankliniella occidentalis, WFT) are often found together on the host plant in China. WFT is an important invasive species that seems to outcompete the native IFT. In order to clarify the interspecific competitions between the two thrips, this study measured the population development of IFT and WFT under sexual and parthenogenetic reproductive modes on two hosts (fresh lentil bean pods with/without honey and pepper plants at seedling/flowering stages) in the laboratory. Results: When reared on fresh lentil bean pods (with/without honey), WFT population size was lower in mixed species populations compared to single species populations but the presence of WFT had nor negative effect on IFT population size. These results were dependent of the reproductive mode. When honey was supplied, the ratio of female-to-male in the progeny of WFT produced under sexual reproductive mode increased significantly in the presence of IFT. On pepper seedlings, mixed populations were more favorable to the population development of IFT at the seedling stage, but more favorable to WFT at the flowering stage. Conclusions: In the early stage of WFT invasion and colonization, the emergence of flowering and honey (nectar) sources may have a positive effect on the population development of WFT. [ABSTRACT FROM AUTHOR]