Anthecological features of Lonicera japonica Thunb. in the environments of Southern Uzbekistan

Background. Identification of spectacular ornamental perennial lianas for urban landscaping in southern cities is important for modern urban greening programs. The aim of this work was to study flowering peculiarities of Japanese honeysuckle (Lonicera japonica Thunb.).Materials and methods. The target material was honeysuckle plants growing in the environments of Southern Uzbekistan. Observations were conducted in 2019–2020 using conventional approaches.Results and conclusion. The inflorescence of L. japonica is an open dibotryoid, with flowers arranged along the lateral axes of the first order. Flowers are bisexual, zygomorphic. Blossoming of flowers in inflorescences occurs acropetally. The flowering period is almost 150–170 days (starts in April and lasts until the end of August). Dichogamy in the form of proterandry is observed in honeysuckle flowers. The male flowering phase comes the first. It starts 1.5–2.0 hours after the opening of the corolla and ends with the drying of the stamens. The corolla turns yellow 36 hours after the blooming of the flower and the stamens begin to dry out. This is the female phase. Over the next 84 hours, the pistil begins to dry out slowly, but the corolla of the flower lasts up to 96 hours. The duration of the female flowering phase is 60 hours. L. japonica is of considerable interest for vertical landscaping of urban communities. Plants remain ornamental for a long time. Studying this species as an essential oil plant is promising, since it contains a significant amount of germacrene D.

Impact of generalist predation on two weed biocontrol agents in New Zealand

The broom leaf beetle (Gonioctena olivacea) and the Honshu white admiral butterfly (Limenitis glorifica) have been introduced into New Zealand as biocontrol agents of the weeds Scotch broom (Cytisus scoparius) and Japanese honeysuckle (Lonicera japonica) respectively. However, neither agent has been successful yet. Larval predation of these species could be a factor affecting their success, and this hypothesis was tested using various predator-exclusion treatments. Survival of broom leaf beetle larvae increased c. five-fold by sleeving Scotch broom seedlings in fine mesh. In contrast, survival was unaffected by excluding either crawling predators using sticky barriers or larger predators using chicken wire. Survival of Honshu white admiral butterfly larvae increased c. ten-fold by excluding either crawling predators using sticky barriers or flying predators using a fine-mesh sleeve. Simultaneously excluding both crawling and flying predators resulted in a c. 23-fold increase in survival. These results suggest that larval predation could be limiting the populations of both broom leaf beetle and Honshu white admiral. Future biocontrol programmes could prioritise candidate agents accordingly.

Analysis of Flower Color Variations at Different Developmental Stages in Two Honeysuckle (Lonicera Japonica Thunb.) Cultivars

Lonicera japonica Thunb., known as Japanese honeysuckle or golden-and-silver honeysuckle, belongs to the honeysuckle family and is native to eastern Asia, including China, Japan, and Korea. Microscopy, spectrophotometry, colorimetry, and the Royal Horticulture Society of Colorimetric Card (RHSCC) were used to compare and analyze the pigment distribution, content, and color variations in the Yujin 2 and Damaohua cultivars at different developmental stages. There were notable differences in the corolla color and the cross-section color between different developmental stages and different varieties. The lightness (L*), redness (a*), and yellowness (b*) values were calculated for each period for the two cultivars to observe variation trends. The chlorophyll content in the corollas of both cultivars showed declining trends with different rates. The chlorophyll content decreased rapidly from the young period to the two white period, and changed gradually from the two white period to the golden period. Moreover, the carotenoid content declined slightly from the young period to the silver period and rose sharply during the golden period. The ratio of these two pigment contents increased dramatically during the golden period: by 11.51 and 6.53 times in ‘Yujin 2’ and ‘Damaohua’, respectively. There were significant differences in corolla color, cross-section color, and the content of three pigments between the two varieties of honeysuckle. distribution and variation of pigments were the key factors affecting the flower color of honeysuckle. This study provides a basis for the identification and breeding of honeysuckle varieties and lays a foundation for further studies on the function and molecular mechanisms of pigments.

Insights from Southeastern US Nursery Growers Guide Research for Sterile Ornamental Cultivars 1

Some ornamental plants important to the nursery and landscape industries escape cultivation, spread to natural areas, and become invasive, outcompeting native plants in those ecosystems. Development of sterile cultivars of these problematic species can be one way to continue their sales yet limit their invasive potential and protect natural areas. To maximize the economic (and ecological) impact of this approach, sterile cultivar research and development should directly address grower needs. We conducted a survey of southeastern US growers to quantify sales of five popular yet invasive ornamentals (Coral ardisia, Chinese privet, Japanese honeysuckle, Heavenly bamboo, and Mexican petunia). Firms ranged from small businesses to large operations with up to $30M in gross annual sales. Respondents expressed a largely positive opinion of sterile cultivar research (74%) and a willingness to sell the sterile cultivars once created. Most (40%) recommended that sterile cultivar research on Heavenly bamboo was most critical, while 30% suggested that Chinese privet was the most important research target of the five species. The industry's willingness to adopt sterile cultivars documented in this survey positions the southeastern US to lead development of sterile cultivars and reduce invasiveness of economically important plants; research and development will be most effective if guided by industry input revealed here. Index words: Invasive species, invasive ornamental, sterile cultivar, ornamental plants, non-invasive, non-native, survey, nursery production, economic impacts. Species used in this study: Coral ardisia (Ardisia crenata Sims); Chinese privet (Ligustrum sinense Lour.); Japanese honeysuckle (Lonicera japonica Thunb.); Heavenly bamboo (Nandina domestica Thunb.); Mexican petunia (Ruellia simplex C.Wright).

Effects of Plant Species, Insecticide, and Exposure Time On the Efficacy Of Barrier Treatments Against Aedes albopictus

ABSTRACT The effect of 5 plant species (arborvitae [Thuja occidentalis], boxwood [Buxus sp., Japanese honeysuckle [Lonicera japonica], rhododendron [Rhododendron sp.], and zebra grass [Miscanthus sinensis]) and 2 rates of lambda-cyhalothrin (3.13 ml and 6.25 ml active ingredient [AI]/liter) on knockdown (1 h) and mortality (24 h) of adult female Aedes albopictus was evaluated over an 8-wk period. A significant difference in knockdown was observed between the 2 rates of lambda-cyhalothrin on the 5 plant species, with the highest proportion of knockdown observed on zebra grass and rhododendron treated at the higher rate. Although mortality was ≥60% and 85% on the 5 plant species at the low and high rates of lambda-cyhalothrin, respectively, a significant difference between the 2 rates was only observed on boxwood and Japanese honeysuckle (P < 0.0001). We also tested the residual toxicity of 3 barrier sprays (lambda-cyhalothrin, bifenthrin, and deltamethrin) and evaluated the efficacy of a short (5-min) exposure to the insecticides on knockdown and mortality of adults over time. Significantly higher knockdown was observed with lambda-cyhalothrin compared with bifenthrin and deltamethrin (P < 0.0001). Mean knockdown was ∼98%, 92%, and 20% for lambda-cyhalothrin, bifenthrin, and deltamethrin, respectively, at week 2, and ∼98%, 0%, and 44%, respectively, 8 wk after treatments were applied. Adult mortality from the 3 chemical treatments, however, remained above 90% throughout the study. Lastly, the trends in mean proportion of knockdown were similar for mosquitoes exposed for either 5 min or 24 h to the 3 chemicals. An overall decline in mean mortality over time, however, was observed for mosquitoes exposed for 5 min to the chemicals compared with mortality from the 24-h exposure. The results suggest that lambda-cyhalothrin can be an effective barrier spray treatment against Ae. albopictus adults because its efficacy is limited little by plant species, it has long residual toxicity, and it is effective following only 5 min of exposure.