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Juraimi A.S.,Technical University of Madrid | Begum M.,Institute of Tropical Agriculture | Mohd Yusof M.N.,Technical University of Madrid | Man A.,MARDI
Plant Protection Quarterly | Year: 2010

Field experiments have been conducted at the MARDI Seberang Perai Research Station for two seasons: main season 2005/2006 (October - February) and off-season 2006 (March - September) to determine the efficacy of herbicides in controlling weeds and their subsequent effect on rice productivity. Ten herbicides widely used and available in the market have been evaluated singly, as mixtures and as sequential applications in direct seeded rice fields during critical period of weed competition under minimal water conditions of less than 2 cm water depth. In main season the hierarchical position of the four dominant weed species out of 10 species were Fimbristylis milliaceae > Lndwigia hyssopifolia > Leptochloa chinensis > Echinochloa crus-galli, this was completely reverse to that of off-season where Echinochloa crus-galli > Leptochloa chinensis > Fimbristylis milliaceae > Limnocharis flava. Seven of the eighteen treatments over the two cropping seasons showed better broad spectrum weed control, increased grain yields and better yield component indicators. Due to variation of the dominant weed infestation between seasons the potential treatments were pretilachlor followed by bentazon/MCPA (T2), cyhalofop-butyl + bensulfuron followed by bentazon/ MCPA (T4), bispyribac-sodium followed by bentazon/MCPA (T6), benthiocarb/ propanil followed by bentazon/MCPA (T8), penoxsulam + benthiocarb followed by bentazon/MCPA (T10), fenoxaprop-p-ethyl/safener + benthiocarb/ propanil followed by bentazon/MCPA (T12) and quinclorac + benthiocarb/propanil followed by bentazon/MCPA (T14) in main season and Pretilachlor followed by bentazon/MCPA (T2), bispyribac-sodium followed by bentazon/MCPA (T6) and penoxsulam + benthiocarb followed by bentazon/MCPA (T10) in off-season. Rice yield losses due to weed competition in unweeded treatments were 60% in main season and 54% in off-season. This experiment showed that sequential herbicide applications at the critical period of weed competition would give a better result compared to a single herbicide application. Source

Soleimani A.F.,3400 UPM Serdang | Zulkifli I.,Institute of Tropical Agriculture | Omar A.R.,3400 UPM Serdang | Raha A.R.,University Putra Malaysia
Poultry Science | Year: 2011

Domestic animals have been modified by selecting individuals exhibiting desirable traits and culling the others. To investigate the alterations introduced by domestication and selective breeding in heat stress response, 2 experiments were conducted using Red Jungle Fowl (RJF), village fowl (VF), and commercial broilers (CB). In experiment 1, RJF, VF, and CB of a common chronological age (30 d old) were exposed to 36 ± 1°C for 3 h. In experiment 2, RJF, VF, and CB of common BW (930 ± 15 g) were subjected to similar procedures as in experiment 1. Heat treatment significantly increased body temperature, heterophil:lymphocyte ratio, and plasma corticosterone concentration in CB but not in VF and RJF. In both experiments and irrespective of stage of heat treatment, RJF showed lower heterophil:lymphocyte ratio, higher plasma corticosterone concentration, and higher heat shock protein 70 expression than VF and CB. It can be concluded that selective breeding for phenotypic traits in the domestication process has resulted in alterations in the physiology of CB and concomitantly the ability to withstand high ambient temperature compared with RJF and VF. In other words, domestication and selective breeding are leading to individuals that are more susceptible to stress rather than resistant. It is also apparent that genetic differences in body size and age per se may not determine breed or strain variations in response to heat stress. © 2011 Poultry Science Association Inc. Source

Soleimani A.F.,3400 UPM Serdang | Zulkifli I.,Institute of Tropical Agriculture | Omar A.R.,3400 UPM Serdang | Raha A.R.,University Putra Malaysia
Poultry Science | Year: 2011

This study aimed to determine the effect of neonatal feed restriction on plasma corticosterone concentration (CORT), hippocampal glucocorticoid receptor (GR) expression, and heat shock protein (Hsp) 70 expression in aged male Japanese quail subjected to acute heat stress. Equal numbers of chicks were subjected to either ad libitum feeding (AL) or 60% feed restriction on d 4, 5, and 6 (FR). At 21 (young) and 270 (aged) d of age, birds were exposed to 43 ± 1°C for 1 h. Blood and hippocampus samples were collected to determine CORT and Hsp 70 and GR expressions before heat stress and following 1 h of heat stress, 1 h of post-heat stress recovery, and 2 h of post-heat stress recovery. With the use of real-time PCR and enzyme immunoassay, we examined the hippocampal expression of GR and Hsp 70 and CORT. The GR expression of the young birds increased following heat stress and remained consistent throughout the period of recovery. Conversely, no significant changes were noted on GR expression of aged birds. Although both young and aged birds had similar CORT before and during heat stress, the latter exhibited greater values following 1 and 2 h of recovery. Within the young group, feeding regimens had no significant effect on Hsp 70 expression. However, neonatal feed restriction improved Hsp 70 expression in aged birds. Neonatal feed restriction, compared with the AL group, resulted in higher CORT on d 21 but the converse was noted on d 270. Neonatal feed restriction appears to set a robust reactive hypothalamo- pituitary-adrenal response allowing the development of adaptive, healthy, and resilient phenotypes in aged quail as measured by a higher hippocampal Hsp 70 expression along with lower CORT. © 2011 Poultry Science Association Inc. Source

Saenphoom P.,Institute of Bioscience | Liang J.B.,Institute of Tropical Agriculture | Ho Y.W.,Institute of Bioscience | Rosfarizan M.,University Putra Malaysia
Asian-Australasian Journal of Animal Sciences | Year: 2013

This study examined whether pre-treating palm kernel expeller (PKE) with exogenous enzyme would degrade its fiber content; thus improving its metabolizable energy (ME), growth performance, villus height and digesta viscosity in broiler chickens fed diets containing PKE. Our results showed that enzyme treatment decreased (p<0.05) hemicellulose and cellulose contents of PKE by 26.26 and 32.62%, respectively; and improved true ME (TME) and its nitrogen corrected value (TMEn) by 38% and 33%, respectively, compared to the raw sample. Average daily gain (ADG), feed intake and feed conversion ratio (FCR) of chickens fed on different dietary treatments in the grower period were not significantly different. Although there was no difference in feed intake (p>0.05) among treatment groups in the finisher period, ADG of chickens in the control (PKE-free diet) was higher (p<0.05) than in all treatment groups fed either 20 or 30% PKE, irrespective of with or without enzyme treatment. However, ADG of birds fed with 20% PKE was higher than those fed with 30% PKE. The FCR of chickens in the control was the lowest (2.20) but not significantly different from those fed 20% PKE diets while birds in the 30% PKE diets recorded higher (p>0.05) FCR. The intestinal villus height and crypt depth (duodenum, jejunum and ileum) were not different (p>0.05) among treatments except for duodenal crypt depth. The villus height and crypt depth of birds in enzyme treated PKE diets were higher (p<0.05) than those in the raw PKE groups. Viscosity of the intestinal digesta was not different (p>0.05) among treatments. Results of this study suggest that exogenous enzyme is effective in hydrolyzing the fiber (hemicellulose and cellulose) component and improved the ME values of PKE, however, the above positive effects were not reflected in the growth performance in broiler chickens fed the enzyme treated PKE compared to those received raw PKE. The results suggest that PKE can be included up to 5% in the grower diet and 20% in the finisher diet without any significant negative effect on FCR in broiler chickens. Copyright © 2013 by Asian-Australasian Journal of Animal Sciences. Source

News Article | March 7, 2016
Site: http://phys.org/biology-news/

The polyphagous parthenogenetic root-knot nematodes of the genus Meloidogyne are considered to be the most significant nematode pest in sub-tropical and tropical agriculture. Despite the crucial need for correct diagnosis, identification of these pathogens remains problematic. Scientists of Ghent University (Belgium), the National Plant Protection Organization (the Netherlands) en het International Institute of Tropical Agriculture (Nigeria) refined the identification of the nematodes.

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