Home About us Contact
|
Home About us Contact | ||
|
|
||
Field Efficacy (field + efficacy)
Selected AbstractsField efficacy of transgenic cotton containing single and double toxin genes against the Asian corn borer (Lep., Pyralidae)JOURNAL OF APPLIED ENTOMOLOGY, Issue 9-10 2004K. He Abstract:, Insect resistant transgenic cotton (Gossypium hirsutum L.) is expected to provide satisfactory control of lepidopteran species in the cotton field. The Asian corn borer, Ostrinia furnacalis (Guenée) (Lep., Pyralidae), is an important component of the lepidopteran pest complex of cotton in China. Insect resistant transgenic cotton cultivars GK2, carrying cry1A gene, and SGK321, carrying both cry1A and CpTI genes, were evaluated for resistance to Asian corn borer. Field trials were conducted with artificial infestation of Asian corn borer at squaring, flowering and flowering-boll cotton plants, which coincided with the generations of natural Asian corn borer occurrence. Damage ratings were significantly reduced in transgenic cotton cultivars both GK2 and SGK321 compared with their parental non-transgenic cotton cultivars Simian3 and Shiyuan321, respectively. In addition, percentage of plants stem bored and number of tunnels per plant were significantly higher on GK2 than on SGK321 in the second generation. Laboratory bioassays were carried out by exposing neonates to plant tissues collected from the field. Tissues assayed included the new leaves, match-head squares and white flowers, which are the tissues initially attacked by the neonates in the field. Low larval survival rates were observed on SGK321 and GK2, contrasting greatly to the high number of survivors found on their non-transgenic cotton tissue isolated throughout the season. However, larval survival was higher on new leaves isolated from late-season transgenic cotton plants and fruit tissues than on early-season. In addition, higher larval survival was observed on GK2 than SGK321 in assays with the late season tissues. This may be associated with reduced levels of available toxin in plant tissues as they age. Both laboratory and field data indicated that SGK321 and GK2 were highly resistant to Asian corn borer. The high level of efficacy for insect resistant transgenic cotton against Asian corn borer offers the potential for season-long control. [source] Field efficacy of a 10 per cent pyriproxyfen spot-on for the prevention of flea infestations on catsJOURNAL OF SMALL ANIMAL PRACTICE, Issue 10 2001L. Maynard The clinical application of a new method for using the insect growth regulator, pyriproxyfen, for controlling flea populations in cat-owning homes is evaluated for the first time. In a multicentric, controlled and randomised trial, 107 flea-infested cats were treated with a minimum dose of 10 mg/kg bodyweight pyriproxyfen as a 10 per cent spot-on application on two occasions, with a three-month interval between doses. For comparison, 99 cats received lufenuron suspension orally, once a month, for six months. Flea counts decreased significantly over time in each group and were significantly lower in the pyriproxyfen group than in cats treated with the reference product. The percentage of ,zero-flea' cats increased from 49 per cent on day 30 to 88 per cent on day 180 in the pyriproxyfen group and from 30 to 71 per cent in the lufenuron group at the same time points (P<0,05). Appropriately timed topical applications of pyriproxyfen, therefore, offer a method of flea control in the domestic environment. [source] Biological control of terrestrial molluscs using Phasmarhabditis hermaphrodita,progress and prospectsPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 12 2007Robbie Rae Abstract Phasmarhabditis hermaphrodita Schneider (Nematoda: Rhabditidae) is a nematode that parasitises a wide range of slug and snail species. It has been formulated into a biological control agent (Nemaslug®) and was commercialised in 1994. It is now available in fourteen European countries. A review is given of all research on P. hermaphrodita, including basic biology, mass cultivation, formulation, host range, application strategies, field efficacy and effects on non-target organisms. The many critical gaps in present knowledge are highlighted, and future research is proposed that will lead to greater understanding of this unusual parasite and may enable its more widespread use in the management of mollusc pests. Copyright © 2007 Society of Chemical Industry [source] Biosuppression of Botrytis cinerea in grapesPLANT PATHOLOGY, Issue 2 2006P. A. G. Elmer There is increasing interest in the use of biological control agents (BCAs) and plant resistance stimulants to suppress botrytis bunch rot in grapes, caused by Botrytis cinerea. Numerous different filamentous fungi, bacteria and yeasts have been selected as potential BCAs for control of grey mould based upon demonstrated antagonism towards B. cinerea. Biological suppression of the pathogen arises via competition for nutrients and space, the production of inhibitory metabolites and/or parasitism. Preformed and inducible grapevine defence mechanisms also contribute to disease suppression by preventing or delaying pathogenic infection. Furthermore, various biotic and abiotic agents can stimulate grapevine defence mechanisms and so elevate resistance to B. cinerea infection. Biosuppression of B. cinerea in vineyards, using BCAs and resistance stimulants, has been inconsistent when compared with that observed in controlled glasshouse or laboratory conditions. This may be attributable, in part, to the innate variability of the field environment. Research to improve field efficacy has focused on formulation improvement, the use of BCA mixtures and combinational approaches involving BCAs and plant resistance stimulants with complementary modes of action. [source] | ||||||||||