Evaluation of four insecticides to protect Nauclea diderrichii (Rubiaceae) seedlings against Orygmophora mediofoveata (Lepidoptera: Noctuidae) shoot borer damage

2017 ◽  
Vol 38 (01) ◽  
pp. 39-45 ◽  
Author(s):  
P.P. Bosu ◽  
E. Acquah ◽  
R.O. Boamah
Keyword(s):  
Seedling Survival ◽  
Iucn Red List ◽  
Tropical Rainforests ◽  
Light Conditions ◽  
Insecticide Treatment ◽  
Shoot Borer ◽  
Trade Name ◽  
Nauclea Diderrichii ◽  
Normal Light ◽  
Lepidoptera Noctuidae

AbstractNauclea diderrichii(De Wild and Th. Dür.) (common name Kusia and trade name, Opepe) is an evergreen tree found throughout the tropical rainforests of West Africa. It is heavily exploited for its timber and listed as vulnerable on the IUCN Red List of Threatened Species. The shoot borerOrygmophora mediofoveataHamps, which attacks the nursery stage, has hampered attempts to establishN. diderrichiiplantations in Ghana. This study examined the potential of four insecticides to protectN. diderrichiiseedlings fromO. mediofoveataattack and damage. Four insecticides–Pyrinex (chlorpyrifos), Dursban (chlorpyrifos), Cerox (dimethoate) and Golan (acetamiprid)–were applied to four-month-oldN. diderrichiiseedlings growing in full sunlight and under shade (80% of normal light), to evaluate their effects on incidence of attack, survival, severity of damage and growth. Insecticide treatment and light conditions had variable effects on the damage and growth of the seedlings after six months of evaluation. Seedling survival was not significantly influenced by the insecticide treatment. Percent survival of insecticide-treated seedlings did not differ significantly from that of control seedlings in full sun; however, under shade survival of treated seedlings was significantly higher than control seedlings. Nonetheless, control seedlings in full sun had higher survival (92.5%) than those under shade (62.5%). Insecticide-treated seedlings in full sun had lower incidence of shoot borer attack than those under shade. In full sun, dieback incidence following shoot borer attack was significantly lower for insecticide-treated than control seedlings. Growth in height and girth of seedlings was influenced positively by both insecticide and light, with girth especially being significantly lower under shade conditions. Currently,N. diderrichiiseedlings are typically raised under shade; however, this study shows that raising seedlings in full sun with insecticide application could result in faster and better growth.

scholarly journals A PHYSIOLOGICAL APPROACH TO CONSERVATION OF FOUR PALM SPECIES: ARENGA AUSTRALASICA, CALAMUS AUSTRALIS, HYDRI- ASTELE WENDLANDIANA AND LICUALA RAMSAYI

REINWARDTIA ◽  
2014 ◽  
Vol 14 (1) ◽  
pp. 237
Author(s):  
Dian Latifah ◽  
Robert A. Congdon ◽  
Joseph A. Holtum
Keyword(s):  
Economic Value ◽  
Red Light ◽  
Tropical Rainforests ◽  
Light Conditions ◽  
Marginal Lands ◽  
Hard Seed ◽  
Palm Species ◽  
Physiological Approach ◽  
Physical Treatments ◽  
Seed Coats

Palms (Arecaceae) are an important component of many tropical rainforests. Many have also been cultivated widely for agricultural commodities with high economic value. They are also important components in rehabilitation of disturbed or marginal lands. Knowledge and application of germination strategies are essential in the cultivation of palms. Many species have seeds that do not germinate readily, even when light conditions are favourable. This research determined the effects of seed coats, light and temperature on germination of Arenga australasica (H. Wendl. & Drude) S. T. Blake ex H. E. Moore, Calamus australis Mart., Hydriastele wendlandiana (F. Muell.) H. Wendl. & Drude and Licuala ramsayi var. tuckeri Barford & Dowe. We examined physical treatments to promote germination or break dormancy, as well as different light and temperature conditions. The results showed that the hard seed coats of the four species slowed imbibition. Scarified seeds germinated best for A. australasica, C. australis and L. ramsayi. The germination of all seeds was inhibited by far red light. The red light requirement suggests that these species prefer to colonise open areas. This implies that dispersal agents, canopy gaps and forest margins may play important roles in promoting regeneration as well as conservation of these palm species.

scholarly journals In situ measurements of isoprene and monoterpenes within a south-east Asian tropical rainforest

2011 ◽  
Vol 11 (14) ◽  
pp. 6971-6984 ◽  
Author(s):  
C. E. Jones ◽  
J. R. Hopkins ◽  
A. C. Lewis
Keyword(s):  
Tropical Rainforest ◽  
East Asian ◽  
Ground Level ◽  
Ambient Air ◽  
Tropical Rainforests ◽  
Light Conditions ◽  
Mixing Ratios ◽  
Volatile Carbon ◽  
Malaysian Borneo

Abstract. Biogenic volatile organic compounds (BVOCs) emitted from tropical rainforests comprise a substantial fraction of global atmospheric VOC emissions, however there are only relatively limited measurements of these species in tropical rainforest regions. We present observations of isoprene, α-pinene, camphene, Δ-3-carene, γ-terpinene and limonene, as well as oxygenated VOCs (OVOCs) of biogenic origin such as methacrolein, in ambient air above a tropical rainforest in Malaysian Borneo during the Oxidant and Particle Photochemical Processes above a south-east Asian tropical rainforest (OP3) project in 2008. Daytime composition was dominated by isoprene, with an average mixing ratio of the order of ~1 ppb. γ-terpinene, limonene and camphene were the most abundant monoterpenes, with average daytime mixing ratios of 102, 71 and 66 ppt respectively, and with an average monoterpene toisoprene ratio of 0.3 during sunlit hours, compared to 2.0 at night. Limonene and camphene abundances were seen to be related to both temperature and light conditions. In contrast, γ-terpinene emission continued into the late afternoon/evening, under relatively low temperature and light conditions. The contributions of isoprene, monoterpenes and other classes of VOC to the volatile carbon budget and OH reactivity have been summarised for this rainforest location. We observe good agreement between surface and aircraft measurements of boundary layer isoprene and methacrolein above the natural rainforest, suggesting that the ground-level observations are broadly representative of isoprene emissions from this region.

scholarly journals The Biology and Ecology of Heliothis-Armigera (Hubner) and Heliothis-Punctigera Wallengren (Lepidoptera, Noctuidae) in Australia - What Do We Know

1986 ◽  
Vol 34 (6) ◽  
pp. 779 ◽  
Author(s):  
MP Zalucki ◽  
G Daglish ◽  
S Firempong ◽  
P Twine
Keyword(s):  
Host Plant ◽  
Population Biology ◽  
Host Plants ◽  
Control Strategies ◽  
Heliothis Armigera ◽  
Host Plant Selection ◽  
Mortality Factors ◽  
Insecticide Treatment ◽  
And Control ◽  
Lepidoptera Noctuidae

The taxonomy and identification of Heliothis armigera and H. punctigera, their distribution and host plants in Australia, the effect of host plant on reproduction and on the development and survival of immature stages, their movements, population biology and dynamics, and their control, are reviewed. Areas where further study is desirable include: the nature of host plant selection and host species preference; adaptability to new cultivars; effects of host plant on development; detailed life-table studies on different host plants; the contribution of predation, parasitism and disease to mortality; factors responsible for fluctuations in populations between years, including the origins of outbreak populations; and control strategies other than insecticide treatment.

scholarly journals Limits of cross-modal plasticity? Short-term visual deprivation does not enhance cardiac interoception, thermosensation, or tactile spatial acuity

2021 ◽  
Author(s):  
Dominika Radziun ◽  
Laura Crucianelli ◽  
H. Henrik Ehrsson
Keyword(s):  
Healthy Volunteers ◽  
Washout Period ◽  
Visual Deprivation ◽  
Control Group ◽  
Light Conditions ◽  
Complete Darkness ◽  
Short Term ◽  
Experimental Conditions ◽  
Normal Light ◽  
Experimental Group

In the present study, we investigated the effect of short-term visual deprivation on discriminative touch, cardiac interoception, and thermosensation by asking 64 healthy volunteers to perform four behavioral tasks. The experimental group contained 32 subjects who were blindfolded and kept in complete darkness for 110 minutes, while the control group consisted of 32 volunteers who were not blindfolded but were otherwise kept under identical experimental conditions. Both groups performed the required tasks three times: before and directly after deprivation (or control) and after an additional washout period of 40 minutes, in which all participants were exposed to normal light conditions. Our results showed that short-term visual deprivation had no effect on any of the senses tested. This finding suggests that short-term visual deprivation does not modulate basic bodily senses and extends this principle beyond tactile processing to the interoceptive modalities of cardiac and thermal sensations.

scholarly journals Shoot Borer Earias Vittella—A Threat to the Indigenous Vegetable Pele Abelmoschus Manihot in the Pacific

Proceedings ◽  
2020 ◽  
Vol 36 (1) ◽  
pp. 95
Author(s):  
Samuel Hone ◽  
Rashmi Kant
Keyword(s):  
Solomon Islands ◽  
Shoot Tips ◽  
Earias Vittella ◽  
Nutritional Security ◽  
Shoot Borer ◽  
Food And Agriculture ◽  
The Pacific ◽  
Field Assessment ◽  
Breeding Programmes ◽  
Lepidoptera Noctuidae

The indigenous vegetable Abelmoschus manihot (Malvaceae) is one of the staple crops in the Pacific island countries. It is known by various local names, including Pele (Samoa, Tonga), Bele (Fiji), Aibika (Papua New Guinea), and slippery cabbage (Solomon Islands). The Food and Agriculture Organisation (FAO) has recommended this as one of the top crops for nutritional security. The leaves of A. manihot are consumed raw, in soups and in various local cuisine. Herbivory is a major problem in growing A. manihot; however, farmers are reluctant to use pesticides. We examined the damage caused by the shoot borer Earias vittella (Lepidoptera: Noctuidae) to three common A. manihot varieties, Green (GN), Red Broad (RB) and Red lobed (RL) in Samoa. In both field and laboratory assessments, E. vittella attacked all the selected varieties. Female lay eggs on shoot tips, and the hatched larvae bore into young shoots. The succulent green variety was found to be more susceptible to the borer attack than red varieties. In field assessment, RL was the least attacked by the borers. In the laboratory bioassay, the larvae that developed on RL were much smaller and weaker than those on the other varieties. In sensory testing, the shoot tips of RN were found to have a tougher/fibrous texture that probably made RN undesirable to the borer. Furthermore, the taller plants were found more vulnerable to borer attack. The study suggests that pruning A. manihot could minimise borer attack; and that RN is a potential variety for future breeding programmes.

The effect of light and darkness on the production of cercariae of Schistosoma haematobium from Bulinus globosus

1987 ◽  
Vol 61 (4) ◽  
pp. 291-296 ◽  
Author(s):  
K. M. Raymond ◽  
A. J. Probert
Keyword(s):  
Schistosoma Haematobium ◽  
Continuous Illumination ◽  
Light Conditions ◽  
Dark Treatment ◽  
Bulinus Globosus ◽  
Normal Light ◽  
Peak Emission ◽  
Evening Peak ◽  
Second Peak ◽  
Effect Of Light

ABSTRACTThe cercariae of Schistosoma haematobium showed a diurnal periodicity of emergence from Bulinus globosus in a twelve hour light/dark cycle. Peak emission occurred at 11.00 hrs with a smaller peak at 20.00 hrs, following the start of the period of darkness. In continuous illumination this second peak was not seen, indicating that only the morning peak is circadian in origin. The evening peak occurs in response to dark treatment and can be produced by periods of darkness ranging from eight seconds to one hour. The longer the period of dark treatment the longer the rise in output is maintained on return to light conditions. Subjection of snails to periods of dark treatment during the normal light period caused a reduction in the evening peak with the largest effect seen following the longest period of darkness. An increased output of cercariae was seen following fifteen minutes exposure to a range of light intensities, the largest increase occurring at 10 000 and 7000 lux and complete darkness. The rapidity of this reaction to variations in light intensity suggests that the cercariae of S. haematobium are showing emergence in response to shadows.

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