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AbstractIncreasing resources use efficiency in intensive cultivation systems of maize (Zea mays L.) can play an important role in increasing the production and sustainability of agricultural systems. The objectives of the present study were to evaluate DM yield and the efficiency of inputs uses under different levels of water, nitrogen (N) and phosphorus (P) in maize. Therefore, three levels of irrigation including 80 (ETc80), 100 (ETc100) and 120% (ETc120) of crop evapotranspiration were considered as the main plots, and the factorial combination of three levels of zero (N0), 200 (N200) and 400 (N400) kg N ha?1 with three levels of zero (P0), 100(P100) and 200 (P200) kg P ha?1 was considered as the sub plots. The results showed that increasing the consumption of water and P was led to the reduction of N and P utilization efficiency, while RUE increased. WUE was also increased in response to application of N and P, but decreased when ETC increased. DM yield under ETc80 treatment reduced by 11 and 12%, respectively, compared to ETc100 and ETc120 which was due to reduction of cumulative absorbed radiation (Rabs(cum)) and RUE. Under these conditions, changes of stomatal conductance (gs) had little effect on DM yield. It was also found that N limitation caused 11 and 20% reduction in DM yield compared to N200 and N400, respectively. This yield reduction was mainly the result of decrease in RUE. By decreasing Rabs(cum), P deficiency also reduced DM yield by 5 and 9%, respectively, relative to P100 and P200 treatments. 相似文献
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Nine phytoseiid species were tested to evaluate their potential as predators ofEutetranychus orientalis (Klein).Typhlodromus atbiasae Porath and Swirski,Amblyseius barkeri (Hughes) andAmblyseius olivi Nasr and Abou-Awad had a shorter developmental period thanTyphlodromus transvalensis (Nesbitt).Typhlodromus athiasae andAmblyseius barkeri showed the highest oviposition rates.Amblyseius olivi showed a low rate of oviposition althoughTyphlodromus transvalensis has not able to lay any eggs. Immatures survival ofTyphlodromus talbii Athias Henriot,Typhlodromus balanites El-Badry,Amblyseius badryi. Yousef and El-Borolossy,Amblyseius cabonus (Schicha) andAmblyseius lindquisti Schuster and Pritchard were very low onEutetranychus orientalis and all failed to develop to adulthood. 相似文献
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Samaneh Solaymani Ahmad Ayatollahi Mehrgardi Ali Esmailizadeh Llibertat Tusell Mehdi Momen 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(5):423-437
In recent years, with development and validation of different genotyping panels, several methods have been proposed to build efficient similarity matrices among individuals to be used for genomic selection. Consequently, the estimated genetic parameters from such information may deviate from their counterpart using traditional family information. In this study, we used a pedigree-based numerator relationship matrix ( A ) and three types of marker-based relationship matrices () including two identical by descent, that is and and one identical by state, as well as four Gaussian kernel () similarity kernels with different smoothing parameters to predict yet to be observed phenotypes. Also, we used different kinship matrices that are a linear combination of marker-derived IBD or IBS matrices with A, constructed as , where the weight () assigned to each source of information varied over a grid of values. A Bayesian multiple-trait Gaussian model was fitted to estimate the genetic parameters and compare the prediction accuracy in terms of predictive correlation, mean square error and unbiasedness. Results show that the estimated genetic parameters (heritability and correlations) are affected by the source of the information used to create kinship or the weight placed on the sources of genomic and pedigree information. The superiority of GK -based model depends on the smoothing parameters (θ) so that with an optimum θ value, the GK -based model statistically yielded better performance (higher predictive correlation, lowest MSE and unbiased estimates) and more stable correlations and heritability than the model with IBD, IBS or kinship matrices or any of the linear combinations. 相似文献
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R. U. Momen S. M. S. Huda M. K. Hossain B. M. Khan 《林业研究》2006,17(4):285-288
Introduction Bangladesh is a land hunger country having about 14.4 million hectares of land with a population of 133 million (BBS 2003). Of the total land area, about 1.48 ×106 hm2 are designated as government forest land, 0.72 million hectares are of Un… 相似文献
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A common objective in commercial reforestation is to plant seedlings that will produce superior adult trees. Long forest management planning horizons and life spans of most forest trees complicate the prediction of growth and performance of adult trees originating from planted seedlings of unknown genetic origin. We used multivariate statistics to identify and rank a set of seedlings characteristics that could predict the performance of mature trees in Pinus ponderosa. Results indicated that metabolic heat rate (q), a measure of total metabolism, of one-year-old foliage during the peak growth in May, was the most important seedling characteristic that predicted mature-tree performance. Increased metabolic heat rate in seedlings corresponded with greater vigor of mature trees. Additionally, seedling basal stem diameter (D), height (H), and needle length (NL), measured in November, were, in order of importance, other variables that defined the vigor class of the mature clones. However, these seedling morphological characteristics correlated negatively with vigor classification of the mature clones, contradicting the notion that greater D and/or H during the seedling stage may indicate a greater vigor at maturity. 相似文献
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Three factors were examined to determine their effect on the reproduction and sex-ratio in the predacious miteAmblyseius zaheri Yousef & El-Borolossy in the laboratory. The factors studied included multiple matings, disturbed mating and age of mating females. Fecundity of females mated more than once was 3 times higher than in females mated only once. Artificial curtailment of copulation to 120, 60 and SO min resulted in reduction of fecundity and oviposition period. The Age of mated females has an influence also on fecundity, old females produce fewer eggs compared with young females under constant condition of abundant prey. All 3 factors studied have no influence on the sex-ratio of the progeny. 相似文献
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Saleem M Rahim IU Rueff H Khan M Khan M Wiesmann U Muhammad S 《Tropical animal health and production》2012,44(6):1297-1302
This study evaluates the effect of management on the undocumented Achai cattle reproductive performance in transhumant farming systems (TFS) and in sedentary farming systems (SFS) in northwestern Pakistan. Data were collected from 172 households in TFS and 270 households in SFS to analyze the effect of farming systems, parity, and calving season on key reproductive traits. The results show that farming systems significantly affect pubertal age, while parity has no significant effect on any of the key traits. The calving season significantly affects the postpartum anoestrus interval in TFS only. More than 50% of the cows in both systems have postpartum anoestrus intervals and calving intervals within the recommended values for cows in tropical countries. Achai cows have high first-service conception rates (70% and 71% for TFS and SFS, respectively) and require a relatively small number of services per conception (1.53 ± 0.06 and 1.48 ± 0.05 SE for TFS and SFS, respectively). This local breed thus warrants conservation under both farming systems. 相似文献
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Dr. F. M. Momen 《Journal of pest science》1993,66(8):148-150
InA. barkeri a relation was found between the duration of copulation and the resulting egg production. After 15 min of copulation no eggs were produced but after respectively 30, 60, 120, 180 min an increasing number of eggs were deposited. A male showed a high reproductive ability for more than 16 days and was able to mate more than once in excess of females, with maximum of six times. The effect of single and multiple mating on longevity, fecundity and sex ratio of the predacious miteAmblyseius barkeri (Hughes) was studied. Fecundity of females mated more than once was twice as females mated only once. 相似文献