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With the burgeoning population of the world, achieving the food security has become a challenge to mankind; as a result only yield maximization is becoming the last word of modern agriculture. Although this approach is satisfying the food demand to almost a desirable extent, but is directly and indirectly causing negative impact on quality of the product, environment and overall human health. This system is mostly based on the use of heavy doses of herbicides to control weeds. Therefore, these experiments were conducted in order to investigate a quick seedling test for allelopathic potential of rice cultivars [Egyptian Jasmine (E. Jasmine) and sakha 104] and allelopathic potential of methanol extract of rice cultivars seedlings and as sown rice cultivars on seed germination %, growth and anatomical parameters of the two tested rice weeds (Echinochloa crus-galli and Echinochloa colonum). The obtained results indicated that, reduction in seed germination %, growth parameters of the two tested rice weeds were recorded by methanol extract of allelopathic rice cultivar (E. Jasmine) and as sown with rice cultivars application. Anatomical changes were obtained in the both rice weeds treated with methanol extract of rice cultivar(E. Jasmine). This may led to avoid or at least reduce the frequent use of herbicides in rice crop production sector. These results suggest that rice plant methanol extract may be a source of natural herbicide (bioherbicide).

The purpose of this research to know the quality of the question quantitatively (reliability, validity, distinguishing features, level of difficulty, and quality detractors). This research was a descriptive research. The population was all the answer sheets of students Mid Semester Exam II IPA class VIII SMP Pembangunan Laboratorium UNP and SMP Pertiwi Padang Siteba in academic year 2015/2016. Sample technique using total sampling with sample was 225 students answer sheets. Data were analyzed using the program ANATES ver.4.0.2. Based on the results of the research, then obtained: 1) the reliability of 0.55 with sufficient criteria; 2) the validity of 15% valid and 85% invalid; 3) distinguishing features about 15% good, 53% moderate and 13% bad; 4) the level of difficulty about 8% is very difficult, 25% difficult, 62% medium and 5% easy; 5) quality detractors about 88% of working and 12% do not function properly. Thus, it can be concluded that the matter has not met the criteria of a good question, so the need for revision.

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The objectives of this investigation were to study the effect of herbicide bispyribac-sodium at rate of 16 g a.i/fed on Oryza sativ (L.) cv. Sakha 104, Echinochloa crus-galli (L.) and Echinochloa colonum (L.) grown under Egyptian ecosystem (Nile delta ecosystem). Morpho-physiological changes were take into account were growth reduction, chlorophyll pigment content reduction and reduction of some anatomical leaf parameters in O. sativa, E. crus-galli and E. colonum treated with tested herbicide. Moreover, increasing in membrane integrity (permeability) and leaf water deficit and reducing in leaf water contents were obtained in all tested plants treated with bispyribac-sodium. Ultrastructural changes in tested plants after bispyribac-sodium foliar application were noticed as cytotoxic features (programmed cell death). Cytotoxic features were take into account were mesophyll cell plasmolysis, irregular, granular nucleus, reduction in thylakoid membranes in treated plants compared with untreated plants. The obtained results will improve our understanding to tested herbicide mode of action, which may be overcome or reduce the side effects on non-target plant (O. sativa).