ISSN 2756-3839
Research Article
International Journal of Nematology and Entomology Vol. 1 (6), pp. 111-116, November, 2013. © International Scholars Journals
Full Length Research Paper
Estimation of virulence type and level of soybean cyst nematode field populations in response to resistant cultivars
J. W. Zheng1,2 and S. Y. Chen1*
1Southern Research and Outreach Center, University of Minnesota, Waseca, MN 56093; USA.
2Institute of Biotechnology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029, P. R. China.
*Corresponding author. E-mail: [email protected]. Tel: +1 507 837 5621. Fax: +1 507 835 3622.
Accepted 16 March, 2013
Abstract
The use of resistant cultivars is the most common practice in managing the soybean cyst nematode (SCN), Heterodera glycines. Currently, most commercial SCN-resistant soybean cultivars were developed from a single source of resistance, plant introduction (PI) 88788. The effect of crop sequences including rotations of SCN-susceptible soybean ‘sturdy’ with SCN-resistant soybean ‘freeborn’ carrying resistance derived from PI 88788, soybean ‘Pioneer 9234’ carrying resistance derived from PI 548402 (peking), and nonhost corn was studied at two field sites in southern Minnesota, the United States. Parasitic ability of SCN measured as a female index (FI) on PI 88788 and freeborn increased with the number of years freeborn was planted. After more than 5 years of freeborn, either in monoculture or rotation with other soybean cultivars and corn, the SCN population changed from the original race 3 (HG type 0 or 7) to race 1 (HG type 2.7 or 2.5.7). After 10 years of freeborn, the changed nematode population reproduced freely on the once resistant cultivar (FI > 60). There was no selection pressure from the use of PI 88788-resistance on SCN populations that can overcome peking resistance. Planting 3 or fewer years of Pioneer 9234 had no noticeable effect on the virulence phenotype of the SCN population. This study suggests that more cultivars from resistance sources other than PI 88788 are urgently needed for effective management of the nematode in Minnesota and other regions in the world.
Key words: Heterodera glycines, HG type, host-parasite relationship, race, soybean cyst nematode, virulence phenotype.
Zheng JW, Chen SY
Page: 111 - 116
Research Article
Full Length Research Paper
Laboratory assessment of insecticidal properties of Tagetes minuta crude extracts against Brevicoryne brassicae on cabbage
Phoofolo, M. W.*, Mabaleha, S. and Mekbib, S. B.
Department of Biology, National University of Lesotho, P.O. Roma 180, Lesotho, Southern Africa.
*Corresponding author. E-mail: [email protected] or [email protected]. Tel: +266 52213447 or +266 59500795. Fax: +266 22 340000.
Accepted 20 August, 2013
Abstract
The cabbage aphid, Brevicoryne brassicae is one of the most serious insect pests of cabbage in Lesotho. Chemical insecticides for efficient control of this pest are often unaffordable for resource-poor farmers. As a first step in a search for effective pest management techniques that can be affordable and easily available to these farmers, the aphicidal activities of Tagetes minuta crude extracts were evaluated against the cabbage aphid. A comparison was made on lethal and sub-lethal effects of T. minuta crude extracts from acetone, methanol, water and a mixture of acetone/methanol/water (7:7:1, v:v). The solvent system that produced the most toxic extract was the mixture, followed by methanol and water, whereas acetone produced the least toxic extract. The sub-lethal effect on cabbage aphid fecundity was well described by linear regression equations that showed significant reduction in fecundity as the concentration of crude extracts increased. The extract from the mixture solvent system had the strongest effect on fecundity.
Key words: Brevicoryne brassicae, cabbage aphid, Tagetes minuta, crude extracts, lethal concentration, sub-lethal, fecundity.
S. and Mekbib, S. B., M. W., Mabaleha , Phoofolo
Page: 134 - 139
Research Article
International Journal of Nematology and Entomology Vol. 1 (5), pp. 093-101, October, 2013. © International Scholars Journals
Full Length Research Paper
Phytosanitary irradiation in South Asia
M. Aftab Hossain1, J. Guy Hallman2*, A. Shakil Khan1 and M. Saidul Islam1
1Insect Biotechnology Division, Institute of Food and Radiation Biology, Atomic Energy Research Establishment, Savar,
Dhaka 1349, Bangladesh.
2USDA-ARS, 2413 E. Highway 83, Weslaco, TX 78596, USA.
*Corresponding author. E-mail : g[email protected]. Tel: 956 447-6313. Fax: 956 447-6323.
Accepted 23 October, 2013
Abstract
Irradiation has the potential to solve phytosanitary problems related to trade in South Asia. In general, it is the phytosanitary treatment most tolerated by fresh agricultural commodities. Irradiation technology is available in some countries of the region but is only used for phytosanitary purposes for mangoes in India exported to the United States of America since 2007. In this review, we analyze the literature on phytosanitary irradiation, present the protocol for exporting irradiated Indian mangoes, suggest possibilities for the technology in South Asia and discuss further research needs.
Key words: Radiation disinfestation, quarantine treatment, commodity quality, mango export.
M. Aftab Hossain, J. Guy Hallman, A. Shakil Khan and M. Saidul Islam
Page: 93 - 101
Research Article
International Journal of Nematology and Entomology Vol. 1 (1), pp. 010-014, June, 2013. © International Scholars Journals
Full Length Research Paper
Studies on some economic traits and biological characters of regular and reciprocal cross between a multivoltine and bivoltine race of the silkworm Bombyx mori
M. S. Doddaswamy1, G. Subramanya1* and E. Talebi 1, 2
1Department of Sericulture Science, University of Mysore, Manasagangotri, Mysore, Karnataka, India.
2Department of Animal Science, Islamic Azad University, Darab, Fars, Iran.
*Corresponding author. E-mail: subramanyag2000@yahoo. co.in. Tel: 0091-821-2419712, 00919448600178.
Accepted 3 May, 2013
Abstract
In order to understand the genetics of cross breeding system between multivoltine and bivoltine race, a hybridization experiment was conducted by crossing females of multivoltine Pure Mysore race (PM) with males of a bivoltine race C108 and its reciprocals. The F1 and F2 progenies of the above crosses were derived in order to study the economic traits and biological characters. The results of the analysis of the thirteen economic traits in the F1 progeny between the regular and reciprocal crosses clearly indicated that wherever PM is participated as female partner the values of the economic traits are on the higher side than the reciprocals. In regard to the studies on the biological characters, the F1 progeny of a cross of females of PM with males of C108 produced non-diapause eggs exhibiting 23 - 24 days of larval duration and spinning light green cocoons. On the other hand a cross between females of C108 with males of PM produced only diapause type of eggs having larval duration of 22 days which is shorter by 1 - 1.5 days compared to regular cross. The F2 progenies involving both the crosses produced 3:1 ratio diapause: non-diapause eggs and green: white cocoons indicating Mendelian pattern of inheritance for voltinism and cocoon colour. The authors in the present investigation discussed the importance of hemizygous and heterozygous individuals of F1 progeny and its utility in genetics and breeding of silkworm Bombyx mori.
Key words: Regular and reciprocal crosses, Bombyx mori, Economic traits, biological characters.
M. S. Doddaswamy, G. Subramanya and E. Talebi
Page: 10 - 14
Research Article
International Journal of Nematology and Entomology Vol. 1 (1), pp. 001-007, June, 2013. © International Scholars Journals
Full Length Research Paper
The theoretical approach of ecoplexivity focusing on mass outbreaks of phytophagous insects and altering forest functions
Anne le Mellec1*, Jerzy Karg2, Jolanta Slowik3, Ignaczy Korczynski4, Andrzej Mazur4, Timo Krummel1, Zdzislaw Bernacki3, Holger Vogt-Altena1, Gerhard Gerold1 and Annett Reinhardt1
1Landscape Ecology Section, University of Göttingen, Goldschmidtstr 5, D-37077 Göttingen, Germany.
2Research Centre for Agricultural and Forest Environment, Polish Academy of Sciences, Field Station Turew, Szkolna 4, Pl-4-000 Ko cian, Poland.
3Centre for Nature Conservation (CNC), University of Göttingen, von Sieboldstrasse 2, D-7075 Göttingen, Germany.
4Department of Forest Entomology, Poznan University of Life Sciences, Ul Wojska Polskiego 71c, PL-60-637 Poznan, Poland.
*Corresponding author. E-mail: [email protected]. Tel: (+49) 0551-3912134.
Accepted 30 April, 2013
Abstract
Epidemics of forest insects can have deep impacts on ecosystem functioning and dynamics, with consequences for forest economics and forest carbon feedback to climate change. Despite the many roles that insects fulfil in terrestrial ecosystems, their importance in nutrient cycling is not well known (Kosola et al., 2001) . The only instances where herbivores are recognized to have a large effect on ecosystem function are mass outbreaks of particular species like herbivores. However, the climate change induced alterations in precipitation and temperature patterns will undoubtedly affect occurrence, intensity, frequency, magnitude and timing of these phenomena and thus, provoke an increasing susceptibility of hosts and a significantly larger habitat presence of pests. Records show that, in an increasing number of cases severe outbreaks can even cause the complete devastation of vast areas and thus, imply considerable economic losses at a large scale. Down to the present day, it remains uncertain how forest ecosystems will respond to the changing environmental conditions in the long run. This work reports on the possible alterations of forest functions due to mass outbreaks of phytophagous insects with respect to the changing ecosystem service of carbon sequestration ability of forests on the northern hemisphere.
Key words: Forest disturbances, insect mass outbreaks, forest functioning, carbon sequestration.
Jolanta Slowik, Gerhard Gerold and Annett Reinhardt, Andrzej Mazur, Timo Krummel, Holger Vogt-Altena, Zdzislaw Bernacki, Anne le Mellec, Jerzy Karg, Ignaczy Korczynski
Page: 1 - 7