• Journal of Plant Biology
• /
• v.35 no.2
• /
• pp.143-153
• /
• 1992

Nectar secretion from extrafloral nectary cells of Prunus yedoensis was examined by light and electron microscopy. Nectaries were composed of two or three layers of secretory cells and one layer of subsectretory cells. Vascular bundles in the petioles were connected to those of the subsectretory cell layer. Secretory cells had a number of mitochondria with poorly developed cristae. Plastids had little thylakoids and small vesicles, about 0.2 to 0.3 mm in diameter; however, no plastids had starch grains. Calcium oxalate crystals and plasmodesmata were frequently observed in the subsectretory and secretory cells, respectively. And nectar substances were observed in phloem of petiole, subsectretory, and secretory cells of the secretory gland. These results suggested that the nectar moved by symplastic transport through the plasmodesmata. On the other hand, the nectar droplets were observed in the secretory cell walls. in the cuticular layer just beyond of the former, and on the outer surface of the cuticular layer: such observations indicated that a apoplastic movement was involved in the final step of the nectar secretion. Cellular components related to the nectar transport, such as plasma membrane, cell wall and cuticle were not destroyed but intact: it was interpreted as a eccrine secretion.retion.

• Animal cells and systems
• /
• v.7 no.2
• /
• pp.123-125
• /
• 2003

We studied the nectar secretion of the Japanese Camellia (Camellia japonica L.), an evergreen tree and observed its floral visitors during the day. The mean volume of nectar secreted, during daylight (08:31 to 16:30 h) was 30.26$\pm8,29ml$ (SD) (n = 27). During the late afternoon and overnight (16:31 to 08:30 following day), 100.54$\pm54.85$(n = 27) of nectar was secreted. Total volume measured when flowers were sampled once every two hours for an eight-hour period was approximately one-half the volume which was measured when the flowers were sampled only once after eight hours. The mean nectar volume secreted was 8.55$\pm8.3ml$(n = 30) between 08:31 to 10:30, 4.38$\pm$6.1 ml (n = 30) between 10:31 to 12:30, 4.6$\pm5.4ml$(n = 30) between 12;31 to 14:30, and 4.02$\pm3.5ml$(n = 30) between 14:31 to 16:30 hours. During the day, Japanese Camellia flowers were principally visited by the Japanese white-eye (Zosterops erythropleura erythropleura 5.), a native bird, although insects and squirrels also visited to a lesser degree.

• Journal of Korean Society of Forest Science
• /
• v.109 no.4
• /
• pp.512-520
• /
• 2020

We assessed the nectar source potential of a prospective honey plant, Idesia polycarpa, by analyzing nectar volume, free sugar content, and free amino acid content. Idesia polycarpa is a dioecious tree; the males bloom approximately four days earlier than females, and the blooming period is approximately 17 days-from March 14th to March 30th. Upon investigating the patterns of nectar secretion, it was found that male flowers peak on the third day of blooming at 5.0 ± 2.5 μL, and female flowers peak on the second day of blooming, at 1.1 ± 0.4 μL. There was a significant difference between males and females in the total nectar volume (9.7 ± 2.9 μL for males and 1.7 ± 0.5 μL for females) and the dried nectar volume (2.2 ± 0.6 μL for males, 0.8 ± 0.3 μL for females) during the blooming period. The free sugar content of floral nectar was 54.6 ± 15.4 ㎍/μL for males and 20.5 ± 4.9 ㎍/μL for females, and the sugar content per flower was higher in males (170.7 ± 15.4 ㎍) than in females (24.9 ± 5.5 ㎍). Our analysis of the amino acid content showed that 20.4 ± 3.9 mg/L (comprised of 19 amino acids) is produced in male flowers and 3.2 ± 0.1 mg/L (11 amino acids) in female flowers. In the male flower, the main amino acid was glutamine, followed by asparagine and proline, whereas in the female nectar, asparagine was the main amino acid, followed by glutamic acid and glutamine. Idesia polycarpa blooms after the blooming period of a major honey plant, Robinia pseudoacacia, and its nectar volume and nectar characteristics, such as free sugar content and amino acid content, make it a viable honey plant.

• Journal of Environmental Science International
• /
• v.23 no.8
• /
• pp.1385-1394
• /
• 2014

Metcalfa pruinosa was considered to be a very harmful invasive species, due to its high species density in nature and wide range of its host plants. M. pruinosa was distributed in 28 sites among 143 sites. M. pruinosa has wide range and diverse host plants of 52 families 110 species including crop, fruits and forest trees. At present, the identified host plant of M. pruinosa are composed of 62 families and 145 species in total since their first appearance was reported. M. pruinosa was found in roadside 46.7%, followed by forests 33.3% and orchard 20%. Nymphs and adults cause damage to crop and orchard by sucking juice, outbreak of fungi through secretion of wax, and reduction of plant assimilation due to the nectar of nymphs. Also, it reduces the merchantable quality of fruits and thus causes economic damage. It is judged that M. pruinosa has been moved along major road via the traffic vehicles.