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): Superovulatory response of dairy cattle (Bos taurus) in a tropical environment. Theriogenology 47 , 1583-1593. Superovulatory response of dairy cattle (Bos taurus) in a tropical environment. Theriogenology

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Cereal Research Communications
Authors: M. Oyekunle, A. Menkir, H. Mani, G. Olaoye, I.S. Usman, S.G. Ado, U.S. Abdullahi, H.O. Ahmed, L.B. Hassan, R.O. Abdulmalik, and H. Abubakar

Genotype × environment interactions complicate selection of superior genotypes for narrow and wide adaptation. Eighteen tropically-adapted maize cultivars were evaluated at six locations in Nigeria for 2 yrs to (i) identify superior and stable cultivars across environments and (ii) assess relationships among test environments. Environment and genotype × environment interactions (GEI) were significant (P < 0·05) for grain yield. Environments accounted for 63.5% of the total variation in the sum of squares for grain yield, whereas the genotype accounted for 3.5% and GEI for 32.8%. Grain yield of the cultivars ranged from 2292 kg ha–1 for DTSTR-W SYN2 to 2892 kg ha−1 for TZL COMP4 C3 DT C2 with an average of 2555 kg ha−1. Cultivar DT SYN2-Y had the least additive main effect and multiplicative interaction (AMMI) stability value of 7.4 and hence the most stable but low-yielding across environments. AMMI biplot explained 90.5% and classified cultivars and environments into four groups each. IWD C3 SYN F3 was identified as the high-yielding and stable cultivar across environments. ZA15, ZA14, BK14, BK15 and IL15 had environment mean above the grand mean, while BG14, BG15, LE14, LE15, IL14, LA14 and LA15 had mean below the grand mean. ZA, BK, BG, LE and LA were found to be consistent in ranking the maize cultivars. However, Zaria, Birnin Kudu, and Ilorin were identified as the best test locations and could be used for selecting the superior maize cultivars. The identified high-yielding and stable cultivar could be further tested and promoted for adoption to contribute to food insecurity in Nigeria.

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Abstract  

In the present paper the thermal behaviour of Mg-carbonates and -silicates is reviewed and discussed, based on own DTA investigations and data from the literature. Mg-bearing minerals in soils and sediments offer informations about the palaeoenvironment and palaeoclimatology of sediments and soils and - thus - the study of their crystal chemical compositions by means of (differential) thermal analysis informs about environmental conditions of (sedimentary Mg-) mineral (trans-) formations. The paper stresses (1) the interrelations between decomposition temperatures of (Mg-) carbonates and substitution processes and is (2) concerned with the interdependence between the dehydroxylation behaviour of Mg-bearing sheet silicates and their crystal chemical composition.

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The paper deals with the transfer factors (TF) generated for a few varieties of leafy vegetables (spinach, fenugreek, and amaranths) consumed by the locals around Tarapur atomic power station environment in India. The soil and leafy vegetable samples collected from the ambient environment of nuclear site were used for the determination of the TFs and they were compared with TFs generated from pot experiments under controlled conditions for 137Cs. The activity of 137Cs in soil and each vegetable was determined by gamma spectrometry using HPGe detector (35 and 160% relative efficiency) and was reported on dry weight basis for both ambient environment and pot samples. The radioactive effluent containing 137Cs (pH ~7) from nuclear power station was used to spike the soil for pot (size 90 cm × 45 cm × 42 cm) experiment. The TFs obtained for ambient environment and pot experiment were found to be in the range of 0.035–0.592 and 0.0054–0.29, respectively. It is observed that TFs of ambient environment are in good agreement with those obtained in the pot experiment conducted under controlled conditions. Further, the observed TF values at Tarapur nuclear site are comparable with the range of typical IAEA transfer factor values for general leafy vegetation (0.11–2.9) for tropical environment.

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There are millions of acres of chemically contaminated lands on which biofuel crops can be planted for dual purposes of biomass production and land reclamation. Phytoremediation is a proven technology for environmental cleanup, particularly in tropical and sub-tropical environments. There are advantages in that multiple growing seasons and increased soil temperature accelerate the clean-up processes. Seeds of 13 tropical and temperate plant species were germinated and grown for 10 days in petroleum contaminated soil containing 3148 μg/g of polycyclic aromatic hydrocarbons (PAHs). The results indicate that the presence of PAHs enhanced both emergence and early seedling growth with some of the species tested. Kiawe tree germination rate was 7-fold higher in PAH soils than that in the control media. The potential biofuel grasses sugarcane, banagrass, switch grass, vetiver and miscanthus showed degradation of PAHs in at least one of the amended PAH-contaminated soils in 35 days of growth. Banagrass biomass production in all the treatments was far greater than the other four species. No plant control pots were most effective to reduce PAHs in the un-amended PAH soil. Vetiver degraded all PAHs when planted in the PAH soil amended with 1/3 of the Promix soil (a 2/3 PAH soil volume). Among five biofuel crops tested, banagrass produced a tripled amount or more of biomass than all the other species in the LF-14 un-amended PAH soil or its amended soils. The dry weight (dw) biomass of banagrass averaged ∼3 g/day/3-L pot in all PAH soils and 6 g/day/3-L pot in Promix as harvested at the ground level. Banagrass in 90-cm spacing could produce approximately 30 tons/ha/yr of dry matter in a 70-day crop season. The results warrant further investigation of biofuel crops for phytoremediation and biomass production purposes. Future plantings may be considered using these and other crops in combination with applicable contaminants to help clean up the contaminated environment and reduce petroleum dependency.

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Muchow, R. C. (1988): Effect of nitrogen supply on the comparative productivity of maize and sorghum in a semi-arid tropical environment. I. Leaf growth and leaf nitrogen. Field Crops Research , 18 , 1

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Pollack Periodica
Authors: Vlasta Harbul’áková, Alena Luptáková, Nadežda Števulová, and Pavlína Rutarová

environments, an overview, Los Angeles, Getty Conservation Institute, 1999. Kumar A. Biodeterioration of stone in tropical environments, an overview

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. J. (2005): Water requirement of drip irrigated tomatoes, grown in greenhouse in tropical environment. Agricultural Water Management , 71 , 225--242. Water requirement of drip irrigated tomatoes, grown in greenhouse in

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tropical environment. Field Crops Res. , 11 , 99-109. Canopy development in grain legumes grown under different soil water regimes in a semi arid tropical environment. Field Crops Res

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assessment of crop yields losses due to pests, and environment impact of agro-ecosystems in tropical environments. I. Model description. Agril Systems. 89 :1–25. Pathak H. InfoCrop: A

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