JTAS Vol. 27 No. 1March 2004
JTAS-0276-2004
Mechanism of Paraquat Resistance in Crassocephalumcrepidioides(Benth.) S. Moore During Immature Stage
Ismail B.S., Chuah T.S. & Khatijah H.H.
Keywords
Resistance, herbicide, cuticle, epicuticular wax, Crassocephalumcrepidioides
Abstract
The mechanism of paraquat resistance in Crassocephalumcrepidioidesat the six-leaf stage was investigated. The extractableparaquat was not metabolized by the leaf tissue in the resistant (R) and susceptible (S) biotypes.Therefore, differential metabolism does not appear to play a role in the mechanism of resistance. The S biotypeabsorbed 44% more 14C-paraquat than the R biotype. However, more than 98% of the absorbed 14C-paraquatremained on the treated leaf of both biotypes. The difference in absorption had a negative correlation with theamount of epicuticular wax as well as the cuticle of leaf surfaces in both biotypes. The results of this study suggestthat differential absorption may be a factor that accounts for resistance to paraquat at the six-leaf stage.
JTAS-0277-2004
Intraspecific Polymorphism in Mystusnemurus (C&V) Detected by RAPD-PCR Fingerprinting
SangaLeesanga, Siti ShaporSiraj, Siti KhalijahBaud, Soon Guan Tan & SharrAzniHarmin
Keywords
Mystusnemurus, catfish, RAPD, PCR, Thailand
Abstract
Yellow catfish, Mystusnemurus(C&V), is becoming one of the major freshwater species farmed by aquaculturistsin Southeast Asia. It was of interest to examine levels of genetic sub-population differentiation among samples ofthis species obtained from parts of its range, as well as to compare the genetics of mild and hatchery-bred fish. Thegenetic aspects of variation in the fish, which were collected from eight wild populations throughout Thailand anda hatchery stock, were determined at molecular (DNA) level using the technique of RAPD-PCR fingerprinting. Fivearbitrary primers namely OPA-11, OPA-14, OPA-18, OPA-19 and OPA-20 were chosen to amplify products,which showed 28 polymorphic loci in 9 populations. The highest genetic distance (D) was found between Chainatand Suratthani populations with the value of 0.289, while the lowest was found in Songkhla population andhatchery stock with the value of 0.087. The dendrogram depicts the genetic relationship among populations ofM. nemurus, which are grouped into four clusters according to their regional areas.
JTAS-0278-2004
Comparative Evaluation of Different Plant Residues on the Soil and Leaf Chemical Composition, Growth, and Seed Yield of Castor Bean (Ricinuscommunis)
E.I.MoyinJesu
Keywords
Plant residue, castor bean, soil and leaf chemical composition
Abstract
This work investigated the effect of plant residues such as cocoahusk, ricebran and saw dust on the growth, seedyield, leaf and soil chemical composition of castor bean in 1999 and 2000 at Akure in the rainforest zone ofNigeria, The treatments were applied at 6t/ha, replicated four times and arranged in a randomized complete block(RCB) with NPK 15 -15 -15 fertilizer applied at 300 kg/ha and a control (no fertilizer; no residue). The soiland organic amendments were chemically analyzed. The parameters recorded for castor oil bean were plant height,leaf area, stem girth, soil and leafN, P, K, Ca, Mg, SoilpH, O.M and seed yield. Results showed that there weresignificant increases (p<0,05) in plant height, leaf area index, stem girth, soil and leaf N, P, K, Ca, Mg, soilpH, O.M and seed yield of castor oilplant under different organic amendment treatments compared to the control.The cocoahusk treatments increased seed weight by 55% and 80% in the two crops of castor oil bean to thericebran treatment. Compared to the plant residues, the NPK treatment resulted in the greatest increases in theplant height, leaf area and stem girth but reduced seed yield.
JTAS-0279-2004
Distribution of Food Items of Six Commercially Important Demersal Fishes in the South China Sea
Sakri Ibrahim, Muhaimi Muhammad, Mohd AzmiAmbak, Mohamad ZaidiZakaria, Mansor Mat Isa & SukreeHajisamae
Keywords
Demersal fishes, food items, occurrence method, fish distribution, South China Sea
Abstract
Distribution of food items of six commercially important fish species in waters off the east coast of PeninsularMalaysia were studied. Trawl surveys were conducted in 124 stations in areas between 12 to 200 nautical milesfrom shore covering an estimated area of 27, 785.54 square nautical miles. Stomachs offish species collected wereremoved onboard, preserved and taken to the laboratory for analysis of the contents. The occurrence method wasused to quantify the diet. Penaeus sp. was found to be the main food item of Carangoidesmalabaricus,Nemipterusmarginatus, Priacanthustayenus, and Upeneusbensasiwhile Loligo sp. for Sauridaundosquamisand Sphyraenaforsteri. Sub-areas 0, I, II and III appeared to be the most productive areas forthe studied species and the food items. The results also show that there exist significant relationships between thefood items and fish distribution. Information on the availability and distribution of food items is important forthe management of fishery resources as well as for the efficient exploitation of the species.
JTAS-0280-2004
KajianTerhadapStrukturKomunitiTumbuhanPeriukKeradiHutanPendidikanAlam, UniversitiKebangsaan Malaysia, Bangi, Selangor DarulEhsan
Jumaat H. Adam, DayaniH.Daiman, Geri KibeGopir, A.K. JalaludinPengiranBesar, Ramlan Omar & Hafiza A. Hamid
Keywords
Nepenthes, struktur, komposisispesies, kepadatan, taburan
Abstract
DuaspesiesperiukkeraiaituNepenthersgracilisKorthalsdanN. mirabilis (Loureiro) Drucedirekoddidalamplot berkeluasan 0.1 hektar. Nepenthes gracilisberbezadaripadaN. mirabilis dengankeratanrentasbatangnya yang bersudut, daun yang tidakbertangkai, peristom yang nipis (≥1 mm tebal), permukaanbawahtudungperiukditutupiolehkelenjarmadu yang jarang, dindingdalamperiukditutupisebahagiannyaolehkelenjarpenghadamanjenisterdedahsebaliknyapadaN. mirabilis batangnyaberbentukbulat, daun yangbertangkai, peristome yang tebal (≥1 mm tebal), permukaanbawahtudungperiukditutupiolehkelenjarmaduyang padat, permukaandalamdindingperiukditutupisebahagiannyaolehkelenjarpenghadamanjenispopulasiberbumbung. KepadatanpopulasiN. gracilismengatasipopulasiN. mirabilis masing-masingmempunyai 147 dan 15 individu.KepadatanrendahN. mirabilis adalahkeranaspesiesinisangatcenderunghidupdikawasantanah yang sangatlembapterutamanyadikawasanberpaya.CoraktaburanfasaanakcambahdandewasaN. gracilisdanN. mirabilis adalahsignifikanberkelompok.
JTAS-0281-2004
Differential Responses in Growth, Physiological Processes and Peroxidase Activity of Young Mango (Mangiferaindica) and Citrus (Citrus sinensis L) Plants to Water Deficit
Mohd Razi Ismail, Abd Ghani Muhammad & Ismail Iberahim
Keywords
Water deficits, mango (Mangiferaindica), citrus (Citrus sinensis), water relations, stomatalconductance, peroxidase activity
Abstract
The effects of water deficit on growth, plant physiological processes and peroxidase activity were studied for youngmango (Mangiferaindica) and citrus (Citrus sinensisL) plants in the greenhouse. Under gradually decreasingsoil moisture content, mango and citrus differed in their leaf water potential, stomatal conductance, leaf growthand peroxidase activity. Stomata of both plants responded independently to the changes in leaf water potential assoil drying progressed. The reduction in stomatal conductance in mango was greater than citrus suggesting thatcitrus was able to control water loss better than mango to the changing condition of water availability in the rootzone. Peroxidase activity increased significantly in water stressed citrus plants. There was a 6-10 fold increase inproline content when both species were exposed to water stress. Citrus plants accumulated higher proline levelssuggesting that they can tolerate water stress compared to mango. This was also evident by a faster recovery afterrewatering in citrus compared to mango plants that involved regeneration of new shoots.
JTAS-0282-2004
Predominant Weeds of Some Cereal Crops in the Scrub Savannah Region of Nigeria
Jafun, F.B. & S.D. Abdul
Keywords
Weed, cereal, Bauchi, rice, maize, sorghum
Abstract
A survey was conducted to determine the weed species populations inhabiting cereal farms (maize, rice andsorghum) in some parts of the scrub savannah region of Nigeria during the growing seasons of 1996-1998 withthe aim of providing information for effective weed management. Sixty sites in Gubi, Miri, Inkil, Lukshi andBirshin Fulani were selected for the study. Weed samples were collected within 50cm x 50cm quadrants and wereidentified using standards texts and collections of the herbarium of the AbubakarTafawaBelawa University,Bauchi, Nigeria. In the survey sites, 66 weed species belonging to 58 genera within 18 families were identified.Of these, 41 (62.12%) species were broad-leaves, 17 (25.76%) were grass weeds and 8 (12.12%) were sedges.The dominant weeds were Cyperus, Commelina, Kyllinga, Digitaria, Echinochloa, Imperata, Cynodon,Leucasand Chlorisspecies. The distribution of weed species varied with crop type and site of collection.
JTAS-0283-2004
Effect of Varying Levels and Sources of Dietary Fat on Growth Performance and Nutrient Digestibility in Rabbits
M.L. Egbo, T.A. Adegbola, E.O. Oyawoye & M.M. Abubakar
Keywords
Rabbits, fat, growth performance, digestibility
Abstract
The effects of dietary fat sources and levels on growth performance and nutrient digestibility were investigated incross-breed Lopx New Zealand rabbits. Fifty weaned rabbits were randomly allotted to five dietary treatmentsconsisting of a control (no fat) and four others with fat, either from plant (groundnut oil) or animal (butter)sources, each at two levels (3% and 6%) of inclusion. There were ten rabbits per diet. Rabbits on 6% animalfat-based diet recorded the highest (P<0.01) better in rabbits on 6% animal diet. Organic matter intake (OMI)was observed to be similar between rabbits fed control and 3% animal fat diets. However, the 6% butter fat diet
recorded the lowest. Crude protein digestibility (CPD) was similar in rabbit fed 3% and 6% level of animal fatwhich were the highest while 6% level of plant fat diet had the lowest CPD. These findings show that the inclusionof animal fat at 6% level improved the weight gain and efficiency of feed utilization in rabbits.
JTAS-0284-2004[MSOffice1]
The Impact of Anthropogenic Activities on Heavy Metal (Cd, Cu, Pb and Zn) Pollution: Comparison of the Metal Levels in the Green-Lipped Mussel Pernaviridis (Linnaeus) and in theSediment from a High Activity Site at Kg, PasirPutehand a Relatively Low Activity Site at PasirPanjang
Yap, C.K, Ismail, A., Tan, S.G. & Rahim Ismail, A.
Keywords
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Abstract
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[MSOffice1]JTAS-0284-2004 Short Communication.