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541.
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543.
Animesh Sarkar Qingyue Wang Md. H. Rashid 《Communications in Soil Science and Plant Analysis》2016,47(1):87-100
Effects of arbuscular mycorrhizal fungi (AMF) on the growth, nutrient absorption, and inoculation effectiveness of AMF on pioneer plants Pharagmites japonica (C4) and Polygonum cuspidatum (C3) were evaluated by performing a pot experiment in a greenhouse at Saitama University, Japan. AMF spores were collected from the commercial product, Serakinkon. The average colonization levels of P. japonica and P. cuspidatum were 24–33% and 0.2–0.5% respectively and no colonization was found in sterilized soil treatment. AMF colonization increased the plant dry mass, phosphorus (P), and nitrogen (N) concentrations of P. japonica’s roots, stems, and leaves when AMF applied with natural and sterilized soil compared with only sterilized and natural soil. This was a significant effect for N-loss minimization from soil. Maximum value showed when P. japonica was grown with natural soil in combination with AMF whereas P. cuspidatum showed very less or a negative response to AMF colonization in all cases. 相似文献
544.
Md. Siddiqur Rahman Abdul Mannan Akanda Ismail Hossain Mian Md. Khurshed Alam Bhuiyan Md. Motaher Hossain 《Journal of Crop Science and Biotechnology》2016,19(3):249-258
Background
Cucumber mosaic virus (CMV) is the most serious virus disease affecting chilli (Capsicum annuum L.) worldwide and the absence of natural resistance makes management of CMV outbreaks difficult. The characterization of improved sources of resistance to CMV in chilli would facilitate the development of commercially acceptable chilli varieties with adequate levels of CMV resistance. A total of 30 chilli genotypes were evaluated for their reaction to CMV in field and artificial inoculated conditions during 2010-2011 and 2011-2012. Large differences were observed among genotypes for disease incidence, severity indexes, and yield losses. Based on observed data, genotype CA23 (Noakhali) was identified as resistant, while CA12 (Comilla-2) was categorized as moderately resistant to CMV both in natural and inoculated conditions. Enzyme-linked immunosorbent assay absorbance values of samples taken from CMV-infected leaves corresponded well with visible viral symptoms for these genotypes. The identified C. annuum CA23 and CA12 genotypes represent previously undescribed and potentially useful sources of CMV resistance.545.
Homegardens around the world often exhibit remarkable variation in composition and structure depending on the physiographic
and climatic conditions of the area and a wide variety of household characteristics. This research investigated whether households’
contextual attributes have a quantitative and predictable relationship with homegarden vegetation structure from a total of
402 randomly selected households in southwestern Bangladesh. The central analytical tool to test the relationship between
household characteristics and the homegarden vegetation structure was multiple regression. The moderate to low regression
R
2 values revealed that most household characteristics were not strong predictors of homegarden vegetation structure. Despite
the weak explanatory power of the majority household characteristics, time spent and homestead size had the strongest relationship
with species richness and income in a homegarden. Households being the main source of labor for a majority of households suggest
that outside labor shortage would not influence homegarden vegetation structure. We suggest that women’s active participation
in homegardening activities to reduce gender inequality in the family which will perhaps result in more diverse and economically
viable homegarden. However, increasing population density and the concomitant fragmentation of landholdings to homesteads
may create opportunity for homegarden promotion in Bangladesh. Our results of decreased species richness in the homegarden
with improved roads and proximity to market support the general hypothesis of subsistence homegardens and did not reinforce
the general fears of gradual decline in species richness due to a market economy. Household characteristics had no influence
on the presence of IUCN Red Listed species in the homegarden, except for gender and education of the household head. However,
most homegardeners were unaware about the status of red listed species, suggesting that occurrence of red listed species in
homegardens was by chance. Thus, efforts to improve awareness and to save and conserve rare species from extirpation are needed. 相似文献
546.
Aphidicidal activity of hot and cold water extracts of some indigenous plants, Azadirachta indica A. Juss (neem), Calotropis procera (Aiton) W.T. Aiton (akanda), Polygonum hydropiper L. (biskatali) and Ipomoea sepiaria J. Koenig ex Roxb. (bankalmi), were tested against the bean aphid, Aphis craccivora Koch. Hot water extract of P. hydropiper and A. indica was found to be the most effective (87.6–94.5 and 80.47–89.6% mortality respectively, P < 0.01) among all the extracts. Other hot and cold water extracts also appeared to be useful (59.5–87.5% mortality) as pesticides
for A. craccivora. The highest yield (3.25 kg per plant) was obtained using hot water extract of P. hydropiper followed by hot water extract of A. indica (3.15 kg per plant). The lowest yield (0.32 kg per plant) was recorded from the control block. All the phytoproduct treatments
had significantly (P < 0.01) better yield than the control block. 相似文献
547.
Mohammad Shaheed Hossain Chowdhury ;Md. Abdul Halim ;Nur Muhammed ;Farhana Haque ;Masao Koike 《林业研究》2008,19(3):245-251
A study was conducted to explore the traditional utilization pattern and indigenous management practices of wild date palm (Phoenix sylvestris Roxb) in the rural agrarian regions of Bangladesh. A multistage sampling method with 10% intensity and a semi-structured questionnaire were used for the study. The farmers manage the palm mainly for sap production with which sugar based secondary goods are manufactured. The sap is either used fresh as drink or after some sort of processing as molasses and/or alcoholic beverage. Seven diversified sites support the palm as its habitat and most palms (20.40%) occur in orchards. Besides growing naturally, the palm is also established in orchards using the wildings as the staple planting material. Although the medium category farmers own most of the palms (33%), a considerable portion (28.68%) of it is managed by the landless farmers, who earn a substantial livelihood from the palms. The farmers practice their own indigenous wisdom in every stage of the palm's maintenance from planting through tapping for sap collec- tion to the processing of products. If managed more scientifically on a sustainable basis with the collaboration of farmers' indigenou~ knowledge, this familiar palm could be able to support the rural economy of the country to a great extent. Side by side, it would also be able to contribute to the richness of biodiversity in the region. 相似文献
548.
Md. Abul Kashem Bal Ram Singh S M Imamul Huq Shigenao Kawai 《Water, air, and soil pollution》2008,192(1-4):273-279
Selection of a phytoextraction plant with high Cd accumulation potential based on compatibility with mechanized cultivation practice and local environmental conditions may provide more benefits than selection based mainly on high Cd tolerance plants. In this hydroponics study, the potential of Cd accumulation by three plant species; arum (Colocasia antiquorum), radish (Raphanus sativus L.) and water spinach (Ipomoea aquatica) were investigated. Arum (Colocasia antiquorum L.) plants were grown for 60 days in a nutrient solution with 0, 10 or 50 μM Cd, while radish and water spinach plants grew only 12 days in 0, 1.5, 2.5, 5 or 10 μM Cd. Growth of radish and water spinach plants decreased under all Cd treatments (1.5 to 10 μM), while arum growth decreased only at 50 μM Cd. At 10 μM Cd treatment, the growth of arum was similar to the control treatment indicating higher tolerance of arum for Cd than radish and water spinach. Cadmium concentrations in different plant parts of all plant species increased significantly with Cd application in the nutrient solution. Arum and water spinach retained greater proportions of Cd in their roots, while in radish, Cd concentration in leaves was higher than in other plant parts. Cadmium concentrations in arum increased from 158 to 1,060 in the dead leaves, 37 to 280 in the normal leaves, 108 to 715 in the stems, 42 to 290 in the bulbs and 1,195 to 3,840 mg kg?1 in the roots, when the Cd level in the solution was raised from 10 μM Cd to 50 μM Cd. Arum accumulated (dry weight?×?concentration) 25 mg plant?1 at 10 μM, while the corresponding values for radish and water spinach were 0.23 and 0.44 mg plant?1, respectively. With no growth retardation at Cd concentrations as high as 166 mg kg?1 measured in entire plant (including root) of arum at 10 μM Cd in the nutrient solution, arum could be a potential Cd accumulator plant species and could be used for phytoremediation. 相似文献
549.
Sensing and Uptake of Nitrogen in Rice Plant: A Molecular View 总被引:1,自引:0,他引:1
Md Saiful ISLAM 《水稻科学》2019,26(6):343-355
As a main feature of plant autotrophy, assimilation of inorganic nitrogen(N) is not only of fundamental interest to the crop, but also a crucial factor in crop productivity. N is the main plant mineral nutrient needed for chlorophyll production and other plant cell components(proteins, nucleic acids and amino acids). I highlighted the novel aspects of N responsive sensors, transporters and signaling molecules recently identified in the monocot rice plant, and discussed their potential roles in N sensing and transporting. Furthermore, over the last couple of years, N sensing has been shown to be affected by different external factors, which act as local signals to trigger systemic signaling coordinated by long-distance transport or mobile signals in plant body. Understanding of this complex regulatory network provides a foundation mechanism for the development of novel strategies to increase the acquisition and transportation efficiency of nitrogen under varying N conditions for rice production. 相似文献
550.
Poor grain filling induced by waterlogging is similar to that in abnormal early ripening in wheat in Western Japan 总被引:3,自引:0,他引:3
Abnormal early ripening (AER), a major constraint on wheat production in Western Japan, manifests as sudden leaf senescence shortly after anthesis and results in poor grain filling; this leads to smaller grains and reduced grain yield. It is suggested that overwetting of the soil may be related to AER. We conducted field experiments over 2 seasons (2008-2009 and 2009-2010) in Yamaguchi, Western Japan, with waterlogging treatment using 2 Japanese wheat cultivars, Daichinominori (Western Japanese cultivar) and Haruyutaka (Hokkaido cultivar), which differ in terms of grain growth in the environment of Western Japan. We imposed pre-anthesis waterlogging for 2 weeks in 2008-2009 and post-anthesis waterlogging throughout the grain-filling period in 2009-2010. Pre-anthesis waterlogging had no significant effect on grain yield or grain filling irrespective of cultivar. Post-anthesis waterlogging severely reduced the grain yield by 44% and 36% in Haruyutaka and Daichinominori, respectively. The yield loss was attributable to the smaller grain weight that was a result of slower grain growth rate later in the shortened grain-filling period. Post-anthesis waterlogging induced sudden leaf senescence 1 and 2 weeks after anthesis in Haruyutaka and Daichinominori, respectively, and drastically reduced the photosynthesis and ultimately dry mass accumulation. It also depressed the remobilization of water-soluble carbohydrates (WSCs) from culms to grains leaving more residual WSCs in the culms at harvest (149 and 65 mg g−1 DW in waterlogging and controls, respectively). The results indicate that the reduced grain growth due to waterlogging was attributable to decreased current assimilation and poor remobilization of culm WSCs to grain similar to that in AER plants. These results suggest that injured root function after anthesis might induce early leaf senescence and poor grain filling similar to AER wheat. 相似文献