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101.
Methanolic extracts of 79 Malaysian plants representing 42 families were assessed for antinematodal activity against Bursaphelenchus xylophilus using a fungal-feeding assay. Extracts of 27 plants from 19 families showed antinematodal activity, while 52 species were inactive. Five extracts (Sauropus androgynus, Eugenia polyantha, Areca catechu, Piper betle and Piper nigrum) exhibited very strong activity against Bursaphelenchus xylophilus at a minimum effective dose (MED) of 0·625 mg per ball. Strong antinematodal activity (MED: 1·25–2·5 mg per ball) was shown by the extracts of Spondias cyntherea, Codiageum variegatum, Euodia glabra and Cicca acida. Eleven extracts (Carica papaya, Ipomoea aquatica, Ocimum basilicum, Leea gigantea, Pithecellobium jiringa, Crypteronia paniculata, Myristica fragrans, Murraya koenigii, Leucaena leucocephala, Melastoma malabathricum and Morinda citrifolia) demonstrated moderate activity between MED of 5 and 10 mg per ball, and weak activity was observed in seven extracts (Ipomoea batatas, Cymbopogon citratus, Garcinia atroviridis, Psophocarpus tetragonolobus, Tamarindus indica, Allium odorum and Stenochalaena palustris). © 1997 SCI  相似文献   
102.
Journal of Crop Science and Biotechnology - Flash flood causes a serious damage to rice crops in northern and eastern parts of Bangladesh almost every year. This study was designed to identify...  相似文献   
103.
Postmortem radiographic examinations of animals are commonly performed in judicial investigations to rule out gunshot and fractures. However, there was no available data on radiographic postmortem changes of animals. Forty-one sets of abdominal radiographs of feline cadavers made within 12 h of death were evaluated for postmortem changes. Intravascular gas was detected in 11 of 41 (27%) cadavers. The most common site of intravascular gas was the liver. Intravascular gas was also present in the aorta, femoral artery, celiac and cranial mesenteric arteries, and caudal superficial epigastric artery. Intrasplenic gas was detected in two cadavers. Only two cadavers had distended small intestine. One cadaver had pneumatosis coli. The changes detected were most likely due to putrefaction.  相似文献   
104.
Progesterone (P4) plays a key role in the establishment and maintenance of pregnancy in most mammals. Unravelling the expression of progesterone‐regulated genes can expand the understanding of the embryonic mortality. Accordingly, we studied the relative mRNA expression of the P4‐regulated genes in the buffalo. Uteri were collected from the abattoir and categorized into nonpregnant late luteal phase, stage I (28–38th days of gestation) and stage II (48–56th days of gestation) of pregnancy (n = 6/group). After extraction of total RNA from the endometrial tissues, we carried out qRT‐PCR for determining the relative mRNA expression of the P4‐regulated genes using nonpregnant late luteal phase as calibrator group. The expression of LGALS3BP (essential for maternal recognition of pregnancy) gene was found to be significantly upregulated (p < 0.05), while MUC1 (important for embryo attachment) gene was downregulated in stage I and II of pregnancy. We observed no significant change in the expression of LGALS1, LGALS9 and CTSL genes. The SLC5A11 and SLC2A1 genes (involved in the transport of glucose to endometrium) in early pregnancy were upregulated in the pregnancy stage I (p < 0.05) relative to nonpregnant late luteal phase. The CST3 gene was significantly upregulated in pregnancy stage II (p < 0.01). These results provide molecular insights into the specific pathways involved in foeto‐maternal communication during early pregnancy in buffaloes.  相似文献   
105.
Variation in root architecture is essential for the adaptation of plants to target environments. A non‐destructive gel‐based mini‐rhizotron system was used for root architecture trait phenotyping. This system has facilitated the visualization of root architectural traits in large genotype collection of rapeseed including 94 double haploid (DH) lines from “Express617” x “V8” and 439 inbred lines (ASSYST diversity set). A high‐density Express617‐V8 linkage map was used for quantitative trait loci (QTLs) identification in DH population based on standard composite interval mapping. 6K SNPs were analysed for association mapping of root traits in ASSYST diversity set. A large variation, broad segregation and medium–low heritability of root architectural traits, primary root length and growth rate, lateral root number, lateral root length and lateral root density, were observed. In the double haploid population, 11 QTL regions, and in the diversity set, 38 significant marker–trait associations were detected. Significant marker–trait associations proved that these are quantitatively inherited traits controlled by multiple genes which revealed to proceed for genetic improvement and selection of rapeseed lines with improved root system.  相似文献   
106.
High temperature has deleterious impacts on tomato growth and development and limits its production. Acetyl salicylic acid (ASA) and 24-epibrassinolide (EBL) have been widely reported as stress-ameliorating agents. The effect of exogenous application of varying levels of EBL (0.75, 1.5, and 3 µM) and ASA (0.25, 0.75, and 1.25 mM) on root activity (RA) in terms of 2,3,5 triphenyl tetrazolium chloride (TTC) reduction and root morphological features was evaluated in four-week-old tomato seedlings (cultivar: Mei Jie Lo) grown under high-temperature stress (46°C/4 h per day) for 21 days. The daily heat stress treatment almost ceased the root growth of chemically untreated seedlings. However, both EBL and ASA significantly attenuated the deleterious impacts of heat stress to different extents regarding root activity, total root length, surface area, volume, and number of nodes and connections. Different concentrations demonstrated signature effects. EBL (3 µM) was over all the best treatment to improve root activity whereas ASA (0.25 mM) best enhanced root architecture (net length, volume, and area) as compared to the untreated heat-stressed controls. However, EBL (3 µM) and ASA (1.25 mM) slightly inhibited mean root diameter. It is concluded that under high-temperature conditions, the exogenous EBL and ASA in studied doses improve root morphological features and root activity, hence enhance heat stress tolerance. Both chemical agents can be potential candidates in practical agriculture for extension of tomato growth period in summer by virtue of their heat stress amelioration ability.  相似文献   
107.
Precision Agriculture - Poor land leveling of paddy fields leads to irrigation problems which affect crop establishment and ultimately yield. One way to manage this is to vary the seeding rate...  相似文献   
108.
Ganoderma philippii is a root pathogen of many woody plants in tropical regions and is particularly aggressive to Acacia mangium, which is grown on a 6-year rotation for pulpwood in Indonesia. The disease becomes progressively worse over each rotation and control measures have met with limited success. We studied the population genetics of G. philippii to evaluate the role of sexual and asexual reproduction in its mode of spread. Populations were genetically distinct with high levels of inbreeding, and clonal spread to adjacent trees increased after the first rotation. Despite the high levels of genetic diversity seen at all sampling scales, migration rates appear low. Measures to reduce the underground spread of the pathogen as well as methods to prevent the initiation of new infections from basidiospores will be needed to reduce the incidence of root rot in A. mangium plantations.  相似文献   
109.
Status of organic carbon (C), total nitrogen (N), available potassium (K), calcium (Ca) and phosphorus (P) in three different depths (0-5 cm, 5-15 cm and 15-30 cm) on two hill slopes of 35% and 55% in orange orchard cultivated by the Mro tribe of Chittagong Hill. Tracts (CHTs) were evaluated and compared with those in degraded bush forests, through digging three profiles in each land use. The content of all the five nutrients was found to be higher in the soil of orange orchard than in the soil of forest. But the variation was not consistent for both the slopes. The content varied depth wise also, having the highest value in surface soil in case of both the land uses on both the slopes. A mean available K content was significantly higher in orange orchard than in forest on 55% slope, while it was lower on 35% slope. Surface soil contained the nutrients of K and Ca with the amount of 0.2905-mg·g^-1 soil and 3.025-mg·g^-1 soil respectively in the orchard, while 0.1934-mg·g^-1 soil and 1.6083-mg·g^-1 soil were respectively in the forest. Organic carbon and total nitrogen were found more or less similar in surface soil on both the land uses showing a slight difference. Available P was found only in orange orchard, and in forest it was too little in amount to detect by the spectrophotometer. The degraded forests were poor in nutrient content due to high rate of soil erosion, which would be possible to be improved by bringing it under tree cover as proved by the adaptation of orange orchard there.  相似文献   
110.
This study was conducted to examine the compatibility between the Sarawak Forest Ordinance and Bidayuh Native Customary Laws in Sarawak and to gather the community members’ opinions on the compatibility of these laws. This study was carried out using two research methods, viz. a literature review and a survey among the Bidayuh community in Bau, Sarawak. The documents reviewed were the Forest Ordinance Chapter 126 (1958) and the Adat Bidayuh Order, 1994. There are several notable differences between the two laws in terms of, forest ownership, losing of rights to forest or inheritance, and the management of forest. A list of statements with six interval scales was presented and a majority of Bidayuh community members neither disagreed nor agreed with the statement, (1) Forest Ordinance respects the Bumiputera people’s rights (37.5 %; SD = 1.259) and (2) Forest Ordinance protects the Bumiputera people’s rights (37.5 %; SD = 1.281). The community members are also not sure about the consistency between these two laws (28.1 %; SD = 1.182). These results indicated the need for the State to respect the natives’ rights toward the forest land and its resources, recognize the Bidayuh Native Customary Laws and for the native people to learn about the constitutional provisions. Further studies are needed because the knowledge of Native Customary Law itself cannot guarantee the natives’ future in terms of economic, social and environmental aspects and there is also a need to review the current laws to achieve the objective to protect and preserve the natives’ rights.  相似文献   
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