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101.
We investigated the role of gibberellins-producing endophyte Penicillium janthinellum LK5 associated with Solanum lycopersicum (host), abscisic acid (ABA)-deficient tomato mutant Sitiens and its wild-type Rheinlands Ruhm (Rhe) plants under cadmium (Cd) stress. A 100-μM Cd application to host, Sitiens and Rhe reduced the shoot growth, chlorophyll content and stomatal conductance. However, these parameters were significantly (P?<?0.0011) higher (1.0- to 2.6-folds) in host, Sitiens and Rhe under endophytic association than in non-endophyte infected plants (control) under Cd stress. Furthermore, endophytic association minimized the Cd-induced membrane injury and oxidative stress to host, Sitiens and Rhe plants by reducing electrolytes and lipid peroxidation while increasing the content of reduced glutathione and catalase activities as compared to non-endophyte-infected plants. Stress-responsive ABA content significantly increased (~2-folds) in Sitiens and Rhe under endophyte association, while in host plants it was decreased under Cd stress. Salicylic acid content was ~?1.7-fold higher in host, Sitiens and Rhe plants under Cd stress and endophyte association than in the control. Besides gibberellins production, the endophyte has the potential to solubilize phosphates (12.73?±?0.24 mg/l) since higher P was observed in the roots of Sitiens, Rhe and host plants. Similarly, nutrients like sulfur and calcium were more efficiently assimilated in roots of endophyte-associated plants than control under Cd stress. Conversely, Cd accumulation was significantly decreased (P?<?0.001) in the roots of endophyte-inoculated host, Sitiens and Rhe than control. In conclusion, endophyte symbiosis can counteract heavy metal stress which can exert negative effects on plant growth.  相似文献   
102.
Cucumis setosus Cogn. is a rare, endemic, wild gathered or semi-domesticated vegetable restricted to Maharashtra state and border districts of adjoining states in India. Herbarium and literature survey shows that it is poorly collected and inadequately studied. Morphological characters, basic chromosome number and crossability barriers indicate that Cucumis setosus is a valid species, distinct from C. sativus and endemic to western India. Its morphology, basic cytology, crossability relationship with other Cucumis species, taxonomy, distribution, ecology, conservation, economic importance and viability under cultivation are discussed. Besides, a key to distinguish it from C. sativus var. hardwickii (wild and feral form of C. sativus) and other species having sympatric distribution in the area is also presented. Absence of bitter principle in the fruits makes it a potential germplasm for melon and cucumber improvement as well as direct domestication as a future crop.  相似文献   
103.
The state of urban seedling nurseries in the north-eastern region of Bangladesh is examined with a focus on production and profitability of the enterprises. Twenty-eight sample nurseries out of the 97 nursery enterprises in Sylhet town were selected at random, and operators personally interviewed. It was found that the entrepreneurs are not highly educated though they believed that a basic level of education is required to understand the management of young nursery stock. Labourers of various employment categories work in the enterprises and their wage is determined by their skill, gender and efficiency. Capital and operating costs vary among the enterprises according to land value, production capacity, infrastructure type and workforce size. Production capacity ranges from 10,000 to 5 M seedlings/year with an average 836,000, though actual average production is only 341,000 seedlings/year. The production cost per seedling ranges from Tk. 4 to 50 while sale value ranges from Tk. 10 to 60. The most frequently sold species are Acacia mangium, Swietenia macrophylla, Tectona grandis, Mangifera indica, Litchi chinensis and Cocos nucifera. Nursery techniques and cultural practices adopted by nursery operators depend on the type of species and its silvicultural requirement. Despite some problems, including lack of suitable land for nursery establishment and inadequate level of technical knowledge for high quality seedling management, it seems that production of tree seedlings is a promising profitable small-scale business in the study area.  相似文献   
104.
采用多级采样的方法研究了孟加拉国农村耕作区内棕榈树的传统利用模式和当地的管理经验。农民管理棕榈主要为获取树液产品,生产以糖为主的次生品。树液可直接用作饮料,也可加工成糖蜜或酒精饮料。7块不同地块为棕榈提供生长环境,20.40%的棕榈种植在果园内。尽管中等级的农民拥有多数棕榈(33%),但是主要管理棕榈的是没有土地的农民,他们靠棕榈维持生计。这些农民将自己的智慧应用到棕榈管理当中,从种植到开孔取树液再到产品加工。如果能更科学地管理棕榈,加上农民的智慧,棕榈业将会对当地经济发展起到重要作用,也会丰富当地生物多样性。  相似文献   
105.
In 10 cats, under acute experimental conditions, the effects of distension of the oesophagus on diaphragmatic activity were studied. Bipolar recording electrodes were implanted in the diaphragmatic dome muscular fibres and crura muscular fibres. Electrodes similar to those in the diaphragm were inserted in the oesophageal muscular wall above the hiatus and in the rectus abdominis muscle. Changes in the intrathoracic pressure and blood pressure were recorded by catheters placed in the pleural cavity and carotid artery respectively. Distension of the lower part of the thoracic oesophagus (at the level between the heart and the hiatus, 5 to 7 cm from the hiatus) by inflating a balloon with 10 to 15 ml of air produced a partial or total inhibition of the inspiratory electrical activity of the inner hiatal muscular fibres, while the inspiratory electrical activity of the dome muscular fibres was generally unchanged. This inhibition was increasingly pronounced as the distension volume increased and as the balloon was positioned nearer to the hiatus. During the distension period, only electrocardiographic potentials were recorded on the oesophageal muscular wall and rectus abdominis muscle traces and no significant changes were observed from intrathoracic pressure or blood pressure channels. Distension by means of a balloon either inflated with up to 5 ml of air when placed 5 to 7 cm cranial to the hiatus or inflated with 15 ml of air when localised in the cervical oesophagus and intrahiatally produced no effect. All areas of the diaphragm were silent during expiration.  相似文献   
106.
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   
107.
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   
108.
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   
109.
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   
110.
The possible relationships between the main emulsion components (namely, Arabic gum, xanthan gum, and orange oil) and the physicochemical properties of orange beverage emulsion were evaluated by using response surface methodology. The physicochemical emulsion property variables considered as response variables were emulsion stability, viscosity, fluid behavior, zeta-potential, and electrophoretic mobility. The independent variables had the most and least significant ( p < 0.05) effect on viscosity and zeta-potential, respectively. The quadratic effect of orange oil and Arabic gum, the interaction effect of Arabic gum and xanthan gum, and the main effect of Arabic gum were the most significant ( p < 0.05) effects on turbidity loss rate, viscosity, viscosity ratio, and mobility, respectively. The main effect of Arabic gum was found to be significant ( p < 0.05) in all response variables except for turbidity loss rate. The nonlinear regression equations were significantly ( p < 0.05) fitted for all response variables with high R (2) values (>0.86), which had no indication of lack of fit. The results indicated that a combined level of 10.78% (w/w) Arabic gum, 0.56% (w/w) xanthan gum, and 15.27% (w/w) orange oil was predicted to provide the overall optimum region in terms of physicochemical properties studied. No significant ( p > 0.05) difference between the experimental and the predicted values confirmed the adequacy of response surface equations.  相似文献   
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